Implementation of Lean Construction in IIT Guwahati

BTP REPORT

Implementation of Lean Construction in IIT Guwahati

By

Ankit Bhatla Under the supervision of

Dr. Bulu Pradhan

DEPARTMENT OF CIVIL ENGINEERING

INDIAN INSTITUTE OF TECHNOLOGY GUWAHATI May 2010

CERTIFICATE It is certified that the work contained in the project report entitled “Implementation of Lean Construction in IIT Guwahati”, by Ankit Bhatla (06010407) has been carried out under my supervision and that this work has not been submitted elsewhere for the award of a degree.

Date: 6/5/2010 Dr. Bulu Pradhan Assistant Professer Department of Civil Engineering Indian Institute of Technology Guwahati

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ACKNOWLEDGEMENT I would like to take this opportunity to thank my supervisor Dr. Bulu Pradhan who has been supporting me throughout this research. Also, I would like to thank the following individuals who have helped me in carrying my research: 1. MSc. Moataz Farag & Prof. Gehbauer, University of Karlsruhe: for introducing me to the topic of Lean Construction. 2. Prof. Anjan Dutta – for taking keen interest in the research. 3. Dr. Hemant Kaushik, Dr. L.B.Singh & Mr. Kumar Pallav – for giving valuable suggestions for the Questionnaire. 4. Mr. Arun BorSaikia – for coordinating with Gammon India Pvt. Ltd. and Punjj Lloyd Ltd. 5. Mr. T.J. Singh, Mr. Pallav Barua and Mr. Amal Sarma – for coordinating with the Engineering Cell. 6. Mr. Himon Barua and Mr. J.P. Sarma of Buildrite Constructions 7. Prof. Glenn Ballard – for his Last Planner System. 8. Anurag Upadhyay, Anuran Gayali and Ashish Kumar Singh – for giving some valuable suggestions for my presentation on Lean Construction. 9. Deep Gandhi – for attending my presentation on Lean Construction. 10. My family – for supporting me in my endeavors.

Date: 6/5/2010 Ankit Bhatla

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ABSTRACT Lean construction is a relatively new construction management philosophy which has evolved from Lean Manufacturing principles. Lean construction along with its various tools like the Pull Approach, Just in Time (JIT), Total Quality Management (TQM), Continuous Improvement, Last Planner System, etc. has gathered a lot of momentum in the developed nations. The challenge now lies in implementing it in the developing countries. The essence of Lean Construction is increase in efficiency by elimination of non value adding activities (waste). The aim of the project was to implement the concept of Lean thinking in an ongoing construction project in the IIT Guwahati campus. The project was divided into two phases:

1. The Ist phase involved a questionnaire based survey to identify the wastes affecting the construction process in IIT Guwahati. Delays, Interruptions and Rework were the most critical wastes affecting the construction process as observed from the questionnaire survey. Poor management control, Poor Planning and Shortage of Resources were the major sources of the above mentioned wastes as identified from the survey.

2. In the IInd phase the Last Planner System was applied to a construction site in IIT Guwahati to reduce the wastes affecting the construction process. A 3 ½ months case study was done to achieve the above mentioned aim. The PPC (Percent of Planned Complete) was measured weekly and ranged between 16.67 % and 100%; with an average of 55.84 % for the entire duration of the study. Thus, a feedback mechanism was put in place at the site for the easy identification and removal of the wastes observed at the site. Also, a simplified questionnaire was formulated taking into account the feedback received from the survey already done.

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TABLE OF CONTENTS Page no. Certificate

i

Acknowledgement

ii

Abstract

iii

List of Figures

vii

List of Tables

viii

List of Symbols and Abbreviations

ix

CHAPTER 1: INTRODUCTION

1

1.1 Construction Overview: India

1

1.2 Objective of the Present Work

2

1.3 Structure of the Dissertation

3

CHAPTER 2: ORIGIN OF LEAN PRINCIPLES

4

2.1 Lean

4

2.2 Origin of Lean Principles

4

2.3 Rise of Lean Production

5

2.4 The 4 Sections and the 14 Principles of the Toyota Way 2.4.1 Having a long-term philosophy that drives a long-term

11 11

approach to build a learning organization 2.4.2 The right process will produce the right results

11

2.4.3 Add value to the organization by developing its people and

13

partners 2.4.4 Continuously solving root problems to drive organizational

13

learning 2.5 Tools for Lean Production

14

2.5.1 Cellular Manufacturing

14

2.5.2 Continuous Improvement

14

2.5.3 Just in Time

15

2.5.4 Production Smoothing

16 iv

2.5.5 Standardization of Work

16

2.5.6 Total Productive Maintenance

17

CHAPTER 3: LEAN CONSTRUCTION

18

3.1 Lean Construction

18

3.2 Tools for Lean Construction

21 21

3.2.1 Pull Approach 3.2.2 Multifunctional Task Groups

222

3.2.3 Kaizen

22

3.2.4 Benchmarking

22

3.2.5 A3 Reports

22

3.2.6 Last Planner System

22

3.3 Last Planner System

23

3.4 Application of Lean Construction Principles to the Construction

25

Process 3.4.1 Application of lean construction principles to design

25

management 3.4.2 Application of lean construction principles to construction

26

planning 3.4.3 Application of lean construction principles to construction

26

execution 3.4.3.1 Phase scheduling

26

3.4.3.2 Look ahead process and Last Planner System

27

CHAPTER 4: IDENTIFICATION OF WASTES IN CONSTRUCTION

29

PROCESS 4.1 Identification of Key Wastes and their Sources in Indian Construction Practices

29

4.1.1 Wastes in construction process

30

4.1.2 Sources of wastes in construction process

32

4.1.3 Filling up of the questionnaires

32

4.2 Administering of the questionnaires

33

33

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CHAPTER 5: FINDINGS OF THE QUESTIONNAIRE SURVEY AND DISCUSSION

33 33

5.1 General

36

5.2 Results for IIT Guwahati

39

5.3 Results for Gammon India Pvt. Ltd. and Punjj Llyod Ltd. 5.4 Results of IIT Guwahati combined with Gammon India Pvt. Ltd. and Punjj Llyod Ltd. CHAPTER 6: A SIMPLIFIED QUESTIONNAIRE FOR THE

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IDENTIFICATION OF WASTES IN CONSTRUCTION PROCESS 6.1 Need for a Simplified Questionnaire

41

6.2 Administering of the questionnaires

43

CHAPTER 7: IMPLEMENTATION OF THE LAST PLANNER SYSTEM IN IIT GUWAHATI

45

7.1 Why the Last Planner System?

45

7.2 Selection of a Suitable Construction Site

45

7.3 Information about the Construction Site

45

7.4 Implementation of the Last Planner System

46

7.5 Last Planner System Implementation Results – PPC Analysis

48

7.6 Problems Experienced during the Implementation of the Last Planner

53

System CHAPTER 8: CONCLUSIONS, RECOMMENDATIONS AND FUTURE WORK

55

6.1 Conclusions

55

6.2 Recommendations

55

6.3 Future Work

56

REFERENCES

57

APPENDIX

60

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LIST OF FIGURES Figure No.

Title

Page No.

2.1

Waste in a Truck Chassis Assembly Line

7

2.2

The Toyota Production System

10

3.1

Classification of Causes of Waste

21

3.2

Critical Chain Path Method

22

3.3

Lean Construction

22

3.4

Last Planner System

24

4.1

Cause Effect Matrix to Determine the Main Sources of Wastes

33

Incidence of Waste Categories in form of a Pie Chart (IIT Guwahati) 5.1

Incidence of Waste Categories in form of a Pie Chart (Gammon

34

5.2

India Pvt. Ltd. and Punjj Llyod Ltd.)

37

Incidence of Waste Categories in form of a Pie Chart (IIT Guwahati 5.3

combined with Gammon India Pvt. Ltd. and Punjj Llyod Ltd.)

39

Reasons Analysis Hierarchy – Directives 7.1

Reasons Analysis Hierarchy – Prerequisites

47

7.2

Reasons Analysis Hierarchy – Resources

47

7.3

PPC Variation

48

7.4

Reason Categorization

50 53

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LIST OF TABLES Table No.

Title

Page No.

1.1

Barriers to Entry in Indian Construction Sector

2

2.1

Tradition Production vs. Lean Production

11

3.1

PPC Measurement

28

4.1

Wastes in Construction Processes

31

4.2

Sources of Wastes in Construction Processes

31

5.1

Waste Processes and their Frequencies of Occurrence in the

34

Responses (IIT Guwahati) 5.2

Cause Effect Matrix for IIT Guwahati

36

5.3


37

Responses (Gammon India Pvt. Ltd. and Punjj Llyod Ltd.) 5.4

Cause Effect Matrix for Gammon India Pvt. Ltd. and Punjj Lloyd

38

Ltd. 5.5


39

Responses (IIT Guwahati combined with Gammon India Pvt. Ltd. and Punjj Llyod Ltd.) 5.6

Cause Effect Matrix for IIT Guwahati combined with Gammon

40

India Pvt. Ltd. and Punjj Llyod Ltd. 6.1

Wastes in Construction Processes

42

6.2

Sources of Wastes in Construction Processes

42

6.3

Questionnaire to Identify Wastes and their Sources

44

7.1

Reasons for Plan failure

50

7.2

PPC Analysis

51

viii

LIST OF SYMBOLS AND ABBREVIATIONS Symbol

Description

CCPM

Critical Chain Path Method

LPS

Last Planner System

WIP

Work in Progress

PPC

Percent of Planned Complete

TPS

Toyota Production System

JIT

Just in Time

TQM

Total Quality Management

TPM

Total Productive Maintenance

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CHAPTER 1

Introduction 1.1 Construction Overview: India The construction industry in India is the second largest industry in India after agriculture (Laskar and Murty 2004). It is highly diversified and involved in all spheres of construction like: 1. Infrastructure: Highways, airports, seaports 2. Commercial: Offices, Malls 3. Residential: Apartments, houses 4. Industrial: Refineries, mills The construction industry in India is highly fragmented in which only 0.4% of the total 250,000 can be classified as medium to large firms (based upon the number of people employed per firm). Most of the Indian contractors are not well equipped to handle the growing demand and hence the projects quite frequently run in to time and cost overruns, disputes and lower quality. Another major factor causing delays is the lack of proper “Trust” between the contractor and the owner due to which the disputes often end up as litigations and the work stalled (World Bank Report, 2008). The Indian construction industry is also facing a severe resource crunch in terms of skilled and semi skilled man power. To cater to the growing demand, it has been estimated that the number of civil engineers and diploma holders needs to increase by at least 2 -3 times (World Bank Report 2008). The Indian firms are mostly involved in the “Design-Bid-Build” and “Design-Build” projects, though there is a shift to the “Fast Track” construction processes. To monitor the projects the firms still employ the traditional method of project monitoring which includes the earned value estimate of finding the schedule and cost variances. There is reluctance in the Indian firms to change their mindset and their construction practices, in-spite of the increasing focus on the quality of projects; this is partly due to the lack of global participation in Indian construction industry. The foreign players consider India a non-profitable venture primarily due to corruption, lack of adherence to contracts, absence of proper dispute resolution mechanism (World Bank Report 2008) and hence the big Indian players being few in number tend to enjoy a monopoly over the works. 1

Table 1.1 lists the barriers for the new entrants in the Indian Construction Sector (World Bank Report 2008). Table: 1.1 Barriers to Entry in Indian Construction Sector Parameters Availability of skilled staff

Ranking 1

Operation issues: lands, licenses and governance, clearance 1 Taxation issues

1

Materials cost and availability

2

Contract enforcement and dispute resolution

2

Barriers to entry

3

Subsidies and fiscal concessions

3

Finance cost and availability

4

Sector policy and institutional structure

5

Import procedures

6

Infrastructure issues

6

Industry issues

7

Though the above mentioned problems need significant thought and time, it is imperative that increased emphasis is given to new project management strategies so that the Indian growth story doesn’t meet an abrupt end. The medium and big firms need to look to the developed nations and also China for new strategies and implement them here after some research. This research aimed to introduce the topic of “Lean Construction” to Indian construction professionals. 1.2 Objective of the Present Work The aim of this research was to implement lean construction in IIT Guwahati. For achieving this goal the wastes in the construction process at IIT Guwahati were found from a questionnaire based survey to make them explicit to the various parties involved in the ongoing construction works here. The Last Planner System was then applied to a construction site at IIT Guwahati to reduce / remove these wastes.

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1.3 Structure of the Project Report The project report flows from explaining the origin of lean principles in Chapter 2 to the evolution of lean construction in Chapter 3. Chapter 4 is dedicated to elucidating the research methodology of the research. Chapter 5 explains the main wastes identified from the questionnaire survey. A simplified questionnaire suitable for the Indian Construction companies is presented in Chapter 6 followed by the results from the implementation of the Last Planner System in IIT Guwahati in Chapter 7. Conclusions and recommendations are presented in Chapter 8 followed by the references used in the research. The questionnaire used for the survey along with the performas for the look ahead plan and the weekly work plan of the Last Planner System is presented in the appendix after the references.

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CHAPTER 2

Origin of Lean Principles 2.1 Lean The origin of the term “Lean principles” can be traced to the Japanese manufacturing industry. The term “lean” was first coined by an IMVP (International Motor Vehicle Program) researcher John Krafcik in a Fall 1988 article. He said that to be “lean means to derive more value by using less of everything”. Though different researchers have their own interpretation of lean; the most common among them is a “production practice that considers the expenditure of resources for any goal other than the creation of value for the end customer to be wasteful, and thus a target for elimination”. However, the definition most suitable in the context of this project was given by Bhasin and Burcher (2006), “a philosophy that when implemented reduces the time from customer order to delivery by eliminating sources of waste in production flow”. To understand the meaning of the above few lines, we need to understand the developments which led to the development of the lean principles. 2.2 Origin of Lean Principles The credit for the development of lean principles goes to the Toyota Car Company of Japan which has revolutionized the way of manufacturing of automobiles. From the mass production theory which was being followed by Henry Ford in US, the manufacturing industry today has certainly come a long way. But before elaborating on the contributions of Toyota in the development of lean principles, it is important to understand the reasons behind the need of a new manufacturing technique when Ford was going great guns in delivering the consumer a cheap and yet an efficient product. The automobile manufacturing industry all over the world has always been highly specialized. It is one of the biggest manufacturing industries in the world today employing millions of people worldwide. Automobile industry emerged into the forefront in the late 19th century. Automobiles during those times were considered as a novelty meant only for the riches. This was justified from 4

the fact that at that time there were no large machines and each part had to be worked on by human hands. This required highly specialized labor in order to achieve the same finishing as that obtained by the machines. Also, the demands of the consumers were ever changing and to keep pace with these demands required great research which was obviously lacking from this industry at that time. Henry Ford (1863 – 1947) was quick to realize this problem and eventually established the so called mass production system in his Ford Motor Company. He developed the assembly lines which reduced the cost of production and at the same time increased the product quality. His assembly chain enabled a worker to work from a stationary place as all the tools and materials were delivered to him. This enabled to reduce the working time on the car to a matter of few minutes as compared to hours or even days in other companies. This also resulted in lowering the labor costs per car because of the increase in mechanization. Ford took the division of labor in the company to the extreme. New positions were created to look after almost all aspects of manufacturing. His car had two qualities – it was designed for manufacture and also it could be repaired easily. Also, something totally unheard of during those days, a huge pay increase was awarded to the workers. Ford’s main intention was to abolish the trade unions and instill confidence among his workers. Though Ford succeeded in bringing down costs and delivery time, there was a big flaw in his thinking. He thought that there was an unlimited demand for his product. He didn’t give any importance to variety and hence he thought that the consumer would buy anything that he produces. This belief led to the ultimate demise of the mass production system. The share of market of imported cars was on the rise. The Europeans had also perfected the art of mass production and were flooding the market with their variety. There products were strikingly distinct from their American counterparts and with more features (Womack et. al. 1990). 2.3 Rise of Lean Production When Ford was at its pinnacle of success, a Japanese by the name of Eiji Toyoda set out on a three month long pilgrimage of the Ford factory at Detroit. During the course of his visit he declared that the American method of mass production was not suitable for the Japanese market and also there were a number of flaws in their production system. Thus he along with his production genius Taiichi Ohno developed the Toyota Production system also commonly known as the Lean Production System. But this was not easy, especially because of the aftermath of the World War II and the growing financial slump in Japan. A solution was found to keep Toyota running in which the workers were made a part of the Toyota family

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and guaranteed lifetime employment. Thus Ohno began with his goal of implementing lean production. (Womack et. al. 1990b). Taiichi Ohno in 1988 said: “All we are doing is looking at the time line from the moment the customer gives us an order to the point when we collect the cash. And we are reducing that time line by removing the non-value-added waste.” Ohno observed that the entire process at Ford was rife with Muda (Japanese for waste) and observed the following seven types of wastes at Ford (Womack & Jones 2003): •

Overproduction (production ahead of demand).

•

Waiting (waiting for the next production step).

•

Transportation (moving products that is not actually required to perform the processing).

•

Over Processing (due to poor tool or product design creating activity).

•

Inventory (all components, work-in-progress and finished product not being processed).

•

Motion (people or equipment moving or walking more than is required to perform the processing).

•

Defects (the effort involved in inspecting for and fixing defects).

With an aim to find solutions to remove these wastes, Ohno set out to develop the Toyota Production System. The wastes listed above are described as under (Liker 2004c): •

Overproduction. Producing items for which there are no orders, which generates such wastes as overstaffing and storage and transportation costs because of excess inventory.

•

Waiting (time on hand). Workers merely serving to watch an automated machine or having to stand around waiting for the next processing step, tool, supply, part, etc., or having no work because of stock outs, lot processing delays, equipment downtime, and capacity bottlenecks.

6

•

Unnecessary transport or conveyance. Carrying work in process (WIP) long distances, creating inefficient transport, or moving materials, parts, or finished goods into or out of storage or between processes.

•

Over-processing or incorrect processing. Taking unneeded steps to process the parts. Inefficient processing due to poor tool and product design, causing unnecessary motion and producing defects. Waste is also generated when providing higher-quality products than is necessary.

•

Excess inventory. Excess raw material, WIP, or finished goods causing longer lead times, obsolescence, damaged goods, transportation and storage costs, and delay. Also, extra inventory hides problems such as production imbalances, late deliveries from suppliers, defects, equipment downtime, and long setup times.

•

Unnecessary movement. Any wasted motion that the employees need to perform during the course of their work, such as looking for, reaching for, or stacking parts, tools, etc. Also, walking is waste.

•

Defects. Production of defective parts or correction. Repair or rework, scrap, replacement production, and inspection mean wasteful handling, time, and effort.

The wastes in a truck assembly line are shown in Fig. 2.1.

Fig. 2.1: Waste in a truck chassis assembly line (Liker 2004d) 7

Ohno considered overproduction to be the most dangerous of all wastes as it was the source of most of the other wastes. Over producing a commodity leads to a buildup of inventory somewhere downstream. The main problem with this waste is that it promotes suboptimal behavior in the organization; since plenty of parts are available for use it hampers with the motivation to continually improve operations (Liker 2004c). With the main motive of removing the wastes in production, Ohno and his team developed the Toyota Production System (TPS) or the Lean Production System (Liker 2004e). The main and the most fundamental objective of Lean production is to continually evolve and improve the current system. It means to design a production system that will deliver a custom product instantly on order but maintain no intermediate inventories. The main aims of lean production are as follows (Liker 2004b): •

Eliminating wasted time and resources.

•

Building quality into workplace systems.

•

Finding low-cost but reliable alternatives to expensive new technology.

•

Perfecting business processes.

•

Building a learning culture for continuous improvement.

Ohno realized that in order to move towards the ultimate goals of no waste and perfection he needed to shift the improvement focus from one activity to the entire the delivery system. He along with his colleagues at Toyota started devising plans to reach their goals. He understood that the pressure to keep each machine running at maximum production led to extensive intermediate inventories which he called as “the waste of over production.” And he saw defects built into cars because of the pressure to keep the assembly line moving. Production at all costs meant defects were left in cars as they passed down the line. These defects disrupted downstream work and left completed cars riddled with embedded defects. Rework due to errors could not be tolerated as it reduced throughput, the time to make a car from beginning to end, and caused unreliable workflow. In order to prevent these defects he gave each employee the power to stop the production. In the initial few days there were very frequent stoppages but these resulted into brainstorming sessions where the entire team worked to get the defect sorted out. Soon, there were no halts and the production line was always running. This system design criteria promoted continuous improvement. Zero time delivery of a car meeting customer requirements, with nothing in inventory required tight coordination between the progress of each car down the line and the arrival of parts from supply chains. An 8

inventory control strategy was developed which replaced central push with distributed pull. Pull was essential to reduce WIP. Lower WIP tied up less working capital and decreased the cost of design changes during manufacture as only a few pieces needed to be scrapped or altered. Large inventories are required to keep production in push systems because they are unable to cope with uncertainties in the production system. And large inventories raise the cost of change (Womack et. al. 1990). In an effort to reduce the time to design and deliver a new model, the design of the production process was also carefully considered along with the design of the car. Suppliers were given the responsibility of engineering components to meet design and production criteria. New commercial contracts were developed which gave the suppliers the incentive to continually reduce both the cost of their components and to participate in the overall improvement of the product and delivery process. Toyota thus became a demanding customer but at the same time it also offered suppliers continuing support for improvement.

Fig. 2.2: The Toyota Production System (Liker 2004a) The Toyota Production System can also be understood by the “House analogy” (Liker 2004a), developed by Fujio Cho, the current President of Toyota as shown in Fig. 2.2. In this analogy, the roof of the house represents the goals of best quality, lowest cost, and shortest lead time. There are then the two outer pillars of “just-in-time” and “jidoka”, which in essence means never letting a defect pass into the next station and freeing people from 9

machines automation with a human touch. The center of the system is made up of people. Finally come the foundational elements, which include the need for standardized, stable, reliable processes, and also heijunka, which means leveling out the production schedule in both volume and variety (Liker 2004a). Though, each element of the house by itself is critical, but more important is the way the elements reinforce each other. JIT means removing, as much as possible, the inventory used to buffer operations against problems that may arise in production. The idea of one-piece flow is to make one unit at a time at the rate of customer demand. Using smaller buffers (removing the safety net) means that problems like quality defects become immediately visible. This reinforces jidoka, which halts the production process. This means workers must resolve the problems immediately and urgently to resume production. At the foundation of the house is stability. In mass production, when a machine goes down, there is no sense of urgency: the maintenance department is scheduled to fix it while inventory keeps the operations running. By contrast, in lean production, when an operator shuts down equipment to fix a problem, other operations will soon stop producing, creating a crisis. So there is always a sense of urgency for everyone in production to fix problems together to get the equipment up and running. If the same problem happens repeatedly, management will quickly conclude that this is a critical situation and it may be time to invest in Total Productive Maintenance (TPM), where everyone learns how to clean, inspect, and maintain equipment. A high degree of stability is needed so that the system is not constantly stopped. People are at the center of the house because only through continuous improvement can the operation ever attain this needed stability. People are trained to see waste and solve problems at the root cause by repeatedly asking why the problem really occurs (Liker 2004a).

The differences between the traditional production methodology and lean production are summarized in Table 2.1.

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Table 2.1 Tradition Production vs. Lean Production (MAMTC – Traditional vs Lean 2009)

Scheduling Production Product Cycle Times Batch Size Quality Inspection Layout

Traditional Production

Lean Production

Forecast – Product is pushed through facility. Replenish finished goods inventory. Long – Weeks / Months

Customer Order – Product is pulled through facility. Fill customer orders only.

Large batches moving between operations; product is sent ahead of each operation. Sampling – by inspectors.

Small, and based on one-piece flow between operations.

By department function.

Empowerment

Low — little input into how operation is performed. High — large warehouse of Inventory finished goods, and central Levels storeroom for in-process staging. Low — difficult to handle and Flexibility adjust to. Manufacturing Rising and difficult to control. costs

Short – Hours / Days

100% - at source by workers. By product flow, using cells or lines for product families. High — has responsibility for identifying and implementing improvements. Low — small amounts between operations, ship often. High — easy to adjust to and implement. Stable/decreasing and under control.

The 4 sections and 14 main principles along with the tools behind the Toyota Production system required for its successful implementation are described in the next section. 2.4 The 4 Sections and the 14 Principles of the Toyota Way (Liker 2004g) 2.4.1. Having a long-term philosophy that drives a long-term approach to build a learning organization 1. Management decisions should be based on a long-term philosophy, even at the expense of short-term financial goals. •

The objective should be to work, grow and align the whole organization towards a common purpose that is bigger than making money.

•

Efforts must be made to generate value for the customer, society and the economy.

2.4.2. The right process will produce the right results 2. Continuous process flow should be created to bring problems to the surface. •

Redesign work processes to cut out on the idle time.

11

•

Material and Information must move fast and people and processes must be linked together so that the problems can be detected as they occur.

3. "Pull" systems should be employed to avoid overproduction. •

The downline customers should be given the power to decide what they want, when they want and in what quantity they want.

•

Minimum possible inventory of finished goods should be maintained and restocking should be done only after the customer has taken them away.

•

Customer demands should be the driving force rather than the computer schedules and systems to keep a track wasteful inventory.

4. Level out the workload (heijunka). (Work like the tortoise, not the hare) •

People and workforce should not be overburdened and unevenness in the production schedule should be eliminated.

5. A culture of stopping to fix problems should be inculcated in the organization, to get quality right the first time. •

Quality for the customer should be the ultimate consideration.

•

All modern day quality methods should be made available.

•

The systems for detecting and solving problems should be embedded in the organization.

6. Tasks and processes should be standardized as they are the foundation for continuous improvement and employee empowerment. •

Stable and repeatable methods to maintain predictability, regular timings and regular outputs of processes should be employed.

•

Individuals should be given the freedom to improve upon the standardized practices.

7. Visual control should be used to see the hidden problems. •

Simple visual indicators should be used to help people determine whether they are on the right track or deviating from it.

8. Only reliable, thoroughly tested technology that serves the people and processes should be put in use. •

Technology should aid people, not replace them.

•

A technology should be thoroughly tested before being standardized.

•

The technologies that conflict with the working culture should be rejected at all costs. 12

2.4.3. Add value to the organization by developing its people and partners 9. People who thoroughly understand the work, live the philosophy should be developed into leaders. •

Instead of employing people from outside, give internal people a chance to grow into a leader.

•

A good leader should understand the daily work in great detail so that he can be the best teacher of the company’s philosophy.

10. Develop exceptional people and teams who follow the company' s philosophy. •

A strong and stable culture should be promoted in the organization where the company’s values and beliefs are shared between individuals.

•

Cross-functional teams should be employed to improve quality and productivity and to enhance flow by solving difficult technical problems.

•

Efforts should be made to promote teamwork in the organization.

11. All partners and suppliers should be respected and allowed to grow by offering challenging jobs and incentives. •

Partners and suppliers should be treated as part of the company and with respect.

2.4.4. Continuously solving root problems to drive organizational learning 12. Problem areas require personal attention (Genchi Genbutsu). •

Problems should be identified physically, personally and solutions should be found by observing rather than by relying on some third party or computer information.

•

Comment should be made only on personally verified data.

13. Evaluate all options before making a decision; implement decisions rapidly (Nemawashi). •

Always evaluate all possible alternative before choosing one.

•

Nemawashi is the process of discussing problems and possible solutions with all those who may be affected.

14. A learning organization practice should be promoted through relentless reflection (hansei) and continuous improvement ( aizen). •

After establishing a stable workflow, all efforts must be made towards continuous improvement of the process. 13

•

Processes should be designed so that they require no inventories.

•

Finished projects should be cross checked to determine the shortcomings. All efforts must be made to prevent mistakes from reoccurring.

In the above mentioned principles of the Toyota Production System, several tools of lean production have been implicitly mentioned. They are elaborated in the next section.

2.5 Tools for Lean Production Fawaz Abdullah (2003) has listed out 6 tools for lean production. They are described in the following: 2.5.1 Cellular Manufacturing Cellular manufacturing is a concept employed to increase the variety of products. The shop floor is further subdivided into cells which consist of equipment and workstations that are arranged in such an order that maintains a smooth flow of materials and components through the process. Trained operators are assigned to each of the cells. One obvious advantage of arranging people and equipment into cells is the one-piece flow concept, which states that each product moves through the process one unit at a time without sudden interruption, at a pace determined by the customer’s need. Some more benefits associated with cellular manufacturing include: • Inventory reduction • Reduced transport and material handling • Better space utilization • Lead time reduction • Identification of causes of defects and machine problems • Improved productivity • Enhanced teamwork and communication • Enhanced flexibility and visibility 2.5.2 Continuous Improvement Continuous improvement or Kaizen is another fundamental tool of lean manufacturing. It includes a thorough and a systematic approach to gradual, orderly and continuous improvement. It promotes reduction of inventory as well as reduction of defective parts. One 14

of the most effective tools of Kaizen is 5S, which is often the backbone of an effective lean company. 5S consists of the Japanese words Seiri (Sort), Seiton (Straighten), Seiso (Sweep and Clean), Seiketsu (Systemize), and Shitsuke (Standardize). The underlying concept behind 5S is to look for waste and then to try to eliminate it. Seiri, deals with eliminating those items that are not currently being used on a continuous basis. Seiton means having the right items in the right area at the right time. Items that do not belong to a given area must not be in that area. Seiso deals with cleanliness of the working area. The workplace should look neat and clean and ready to use for the next shift. All tools and items should be in the right place and nothing should be missing. Seiketsu means to maintain a high standard of housekeeping and workplace arrangement. Shitsuke specifies the management’s accountability to train the people to follow housekeeping rules. Management should implement the housekeeping rules in a practiced fashion so that their people can follow them easily. Taken together, 5S essentially means good housekeeping and better workplace organization. Kaizen tools such as 5S not only serve as a mean to increase profitability of a firm but also allow companies to reveal potential strengths and capabilities that were hidden before. 2.5.3 Just-In-Time(JIT) Just in time is the act which attempts to eliminate sources of manufacturing waste by producing the right part in the right place at the right time. It enables the company to become highly flexible by adapting to sudden changes in demand market. However, JIT effectiveness depends heavily on having a strategic alliance between buyers and suppliers. Just-in-time is a critical tool to manage the external activities of a company such as purchasing and distribution. It can be thought of as consisting of three elements: JIT production, JIT distribution (JITD), and JIT purchasing (JITP). i) Just-In-Time Production Just in time production means to produce only when the customer demands, thereby preventing any waste related to overproduction. Thereby, the product gets pulled out of the assembly process only when required. The process goes on as each process pulls the needed parts from the preceding process further up stream. 15

ii) Just-In-Time Distribution JITD requires the exchange of frequent, small lots of items between suppliers and customers; this calls for an effective transportation management system to manage the inbound and outbound material since there are no reserves. However, under JITD having a full truckload sometimes is difficult due to the frequent delivery of smaller lots, which will result in increased transportation costs. To prevent this problem a mixed loading strategy is suggested which enables to have full truckloads and also an increase in the number of deliveries. iii) Just-In-Time Purchasing The idea of JITP is to procure materials as and when they are required. Under JITP, activities such as supplier selection, product development and production lot sizing become very critical. Customer-supplier form an integral part of JITP in which the suppliers are encouraged to take part in the product development. This serves to be mutually beneficial as the supplier’s confidence grows and the customer obtains the technology at a cheaper price. It thus becomes necessary to have a small number of qualified suppliers. Having qualitycertified suppliers shifts the inspection function of quality and piece-by-piece count of parts to the supplier’s site where the supplier must make sure that parts are defect free before they are transported to the manufacturer’s plant. 2.5.4 Production Smoothing Heijunka, the Japanese word for production smoothing, is where the manufacturers try to keep the production level as constant as possible from day to day. It is a concept adapted from the Toyota production system, where in order to decrease production cost it became necessary to balance the demand with supply and thereby not overproducing. To achieve constant production levels, the production schedule should be as smooth as possible to effectively produce the right quantity of parts and efficiently utilize manpower. Inability to do so leads to waste (such as work-in-process inventory) at the workplace. 2.5.5 Standardization of Work A very important principle of waste elimination is the standardization of worker actions. Standardized work basically ensures that each job is organized and is carried out in the most effective manner. This enables to achieve the same level of quality irrespective of the person 16

doing the job. A tool that is used to standardize work is “takt” time. Takt is a German word for beat time and refers to how often a part should be produced in a product family based on the actual customer demand. The target is to produce at a pace nearly equal to the takt time. Takt time is defined by the following equation.

Takt Time TT =

Customerdemand per day Available work time per day

2.5.6 Total Productive Maintenance (TPM) Machine breakdown is one of the most important issues concerning the people on the shop floor as this has the ability to stop the entire production system. Hence it becomes very important to look for effective maintenance strategies. There are three main components of a total productive maintenance program: preventive maintenance, corrective maintenance, and maintenance prevention. Preventive maintenance means to have regular and planned maintenance on all equipment instead of some random check ups. Workers have to carry out regular equipment maintenance to detect any anomalies as they occur. Corrective maintenance deals with decisions such as whether to fix or buy new equipment. E.g. if a machine is always down and its components are always breaking down then it would be better to replace those parts with newer ones. The last component, maintenance prevention means the procurement of the right machine as the maintenance of machines which are difficult to repair and maintain will require a lot of effort and money, and hence result in waste.

17

CHAPTER 3

Lean Construction 3.1 Lean Construction The traditional method of project management has a long history. It is being used to manage all kinds of construction projects ranging from small residential to huge infrastructural projects like bridges and dams. However, in the recent years due to the growing domestic and international competition, development of highly complex and uncertain projects this technique of project management has often come under severe criticisms. The construction industry has been suffering from the problems of low productivity, poor safety, inferior working conditions and most importantly inferior quality. Many have attributed automation and increased computer integration as a solution to the above mentioned problem (Koskella 1997). Hence, there has been little progress in the field of Lean construction over the years. However, recently many parts of construction industry have started to shift towards the lean production theory like prefabricated housing. The main characteristics of the traditional approach are as follows (Saied Kartam et. al 1997): 1. All activities are value adding activities. 2. No distinction is made between processing and flow activities. 3. The total cost is estimated on the basis of the WBS (work breakdown structure). 4. No emphasis is given to the importance of resource flows. 5. All activities are assumed to be independent of each other and it is assumed that reducing the cost of each activity will reduce the cost of the project. 6. It doesn’t take into consideration the effects of poor quality output and effects of variability and uncertainty. 7. Another characteristic is that work passes linearly from one process to the other.

Another significant feature or rather a flaw of CCPM of project management is the fact that all the cost and time over runs are attributed to the fact that the contractor’s workers fail to follow the schedules and budget while construction. No question is ever raised against the planning which precedes the construction. It has been observed that the majority of the 18

failures are a result of bad or incomplete planning on the part of planners (Ballard & Howell 1997a). Many uncertainties are not incorporated into the schedules by the top management as the only motive is to win the contract. The schedules are derived from experiences based on the history of other so called similar projects. Contractors still do not give importance to the fact that all construction processes are different and hence it is not correct to establish detailed schedules at the onset and trying to follow the same. The consequence of such an action is disastrous for the contractor as the quality of the construction is compromised and a lot of time and money has to be spent on rework. “Lean construction is the application of lean production principles in the construction industry” (Koskella 1998). However, the lean production principles cannot be applied directly to the construction industry. There is a marked difference in the construction industry from its manufacturing counterpart. The main problem that lies in the road towards lean construction is that most companies do not see construction as a flow and conversion based process. They believe that all activities are conversion based and hence they do not try to reduce the Wastes in construction. Past researchers (Serpell et al. 1997) have identified the following wastes in construction: •

Waiting for resources

•

Travelling time movement (of operator or machine)

•

Idle time (of operator or machine)

•

Resting

•

Rework

A classification of the main causes behind the wastes has also been provided by Serpell et al. (1997) and is shown in Fig. 3.1.

19

Fig. 3.1: Classification of causes of waste Lean Production in construction in essence tries to reduce the wasteful activities in construction to deliver the product to the owner. Many tools are available to achieve this goal, but in this research we shall focus on Last Planner System developed by Glenn Ballard (Ballard 2000) to remove the wastes and to shield the downstream work from the uncertainties in the upstream construction processes. Most of the wastes listed above are a clear demonstration of lack of adequate planning and management control. Information of the above mentioned wastes beforehand can help the project managers to take extra precaution during the execution of the project. One major solution to the above mentioned wastes can be increased emphasis on short term planning as most of the wastes mentioned above are a result of ineffective short term planning (Serpell et al. 1997). Before starting with the topic of lean construction the main features of the traditional project management system are repeated: the traditional project management practices treats all the activities in construction as value adding activities (those which cannot be removed) and accordingly the construction process is a conversion based process in which one value adding 20

activity leads to another as shown in Fig. 3.2. This states that as soon as one activity is finished the other should start irrespective of the fact whether the other pre requisites of the activity like materials, labor and equipment are available. This model pressurizes the available resources to act fast thereby resulting in a compromise in the quality of the construction. On the other hand lean construction is a flow and conversion based model where a construction process is a collection of conversion processes involving flows of information and materials from one process to the other as depicted in Fig. 3.3.

ACTIVITY 1

ACTIVITY 2

ACTIVITY 3

Fig. 3.2: Critical Chain Path Method

Information Labor

Process

Output

Materials

Fig. 3.3: Lean Construction

3.2 Tools for Lean Construction 3.2.1 Pull Approach This concept is the same as that of lean production. Traditionally inventories are managed using the detailed scheduling techniques wherein the materials are ordered on the basis of the master schedule prepared. With the pull approach the concept of Just in Time is utilized in construction wherein the inventories are kept to the bare minimum and new inventories are ordered based on the current demand. Stocking of materials is wasteful. Its implementation however requires good relation with the suppliers (Ballard and Howell 1997b).

21

3.2.2 Multifunctional Task Groups This concept contradicts the current belief that only specialized workers can produce good quality products. Instead of having a specialty group of workers a multifunctional task group should produce a number of different products. This makes it possible to produce a more complex or more completed product with one production unit. In multifunctional task groups the workers do not have to waste time in waiting for each other to complete the work. However, to achieve the principle of multifunctional task groups, personnel need to be trained intensively in recombining thinking and doing (Melles 1997). 3.2.3 Kaizen (Total Quality Improvement) Kaizen means to continually look for new ways to improve the process by reducing costs and increasing efficiency. It might involve the management asking the production teams to suggest new ideas regularly. A good implementation of Kaizen implicates cost reduction and zero defects in final products. It includes the 5S principle for site management which has been described earlier (Melles 1997). 3.2.4 Benchmarking It is an important tool for standardization of activities, ultimately leading to good construction quality. New methods evolved by means of continuous improvement need to be benchmarked so that they can be implemented at similar situations and can be improved upon at all sites. This tool promotes achievement of high quality work (Tanskanen et. al 1997). 3.2.5 A3 Reports This tool developed by Toyota helps in documentation of key results of problem solving manner in a concise manner. It involves mentioning the theme of the problem, current situation, any improvements / suggestions and the implementation and follow up plan, all on a single A3 sheet. The A3 method is an easy to use, comprehend method and can be implemented only with a paper and pencil. The size of A3 is assumed to be just enough to be able to highlight the important points for discussion. 3.2.6 Last Planner System This tool in simple words can be taken to be an assimilation of the above mentioned tools. It also has a number of other features which are explained below. The main objectives of a production control system like the Last Planner System are as follows (Ballard 2000): 22

1. Manage and mitigate the variability. 2. Assignments and schedules should be sound regarding their prerequisites. 3. The completed assignments should be monitored. 4. Causes for failure to complete the planned work should be investigated and removed. 5. There should be a workable backlog for each crew and production unit. 6. The prerequisites of upcoming assignments should be made ready. 7. The traditional push based construction process model should be incorporated with pull techniques. 8. Traditional project control focuses on hierarchical decision making and thus the decision making process lies in the hands of few and often decision makers are unaware of the ground realities. Decision making powers should be well distributed among the project team. 3.3 Last Planner System Developed by Prof. Glenn Ballard of the University of California at Berkeley (2000), it aims to reduce / remove the uncertainties plaguing the construction project processes. In CCPM there is strict adherence to the master schedule even when great obstacles lie in its path. Supervisors keep on pressurizing the subordinates to produce despite obstacles. Many a time these obstacles result in poor quality output which remain in the project supply chain throughout. Last Planner System (LPS) aims to shift the focus of control from the workers to the flow of work that links them together. The two main objectives of LPS are to make better assignments to direct workers through continuous learning and corrective action and to cause the work to flow across production units in the best achievable sequence and rate as shown in Fig. 3.4.

23

Fig. 3.4: Last Planner System (Abdelhamid 2006). Planning for the project cannot be performed in detail much before the events being planned. Consequently, deciding what and how much work is to be done by a design squad or a construction crew is rarely a matter of simply following a master schedule established at the beginning of the project. Hence it is imperative that LPS focuses on making a 6 -8 weeks look ahead schedule with detailed weekly plans in discussion with the last planners (persons who actually execute the work) based on the current situations. The activities from the master schedule are broken down to great details. Assignments are prepared for the workers to work upon. Ballard (Ballard 2000a) suggested that assignments should satisfy the following criteria before being allocated to the workers: 1. Work should be clearly defined. 2. Work should be sequenced properly. 3. All pre requisites for the work should be obtained and the constraints should be removed. 4. Work should be sized based on the availability of the crew. The assignments satisfying the above criteria enter the workable backlog. All the other assignments are postponed till the time they satisfy the above mentioned criteria. In this way 24

the workers are never overloaded, they only do what they promised and this helps to keep a track of the productivity. Failure to keep commitments is investigated so that they do not occur again. This is done by a factor known as PPC (percent planned complete). Ideally this should be 100% as everyone is expected to keep his commitments but generally a value of 80% is considered to be good. All the above lean construction tools are used in the last planner system. As the Last Planner System involves the pull approach to form a workable backlog, it utilizes the just in time tool, since all the persons involved in the project sit together to form the look ahead schedule, wherein continuous improvement is built into the process. Thus the Last Planner System serves to successfully remove the uncertainties in the construction process.

3.4 Application of Lean Construction Principles to the Construction Process The application of lean construction tools to the construction process will be explained in this section. The construction process is considered as a three phase process: 1. Design 2. Planning 3. Execution 3.4.1 Application of lean construction principles to design management Tzortzopoloulos and Formoso (Tzortzopoloulos and Formoso 1999) suggested building of design models by integration of the three concepts of lean construction (design as conversion, design as flow and design as value generation). The terms like conversion, flow and value generation have the usual meanings like that in lean construction. They have mentioned a few guidelines which have also been stated by Ballard and Koskella (Ballrd and Koskella 1998): 1. Having some degree of flexibility in the sequence of design activities. Not defining activities in a very fine level of detail and encouraging team work. 2. Involvement of designers in joint solutions. 3. Direct interactions between designers and customers. 4. Explicit and healthy client supplier relations. 5. Always working with a set of design alternatives.

25

By making use of the integrated models, the share of wasteful activities can be reduced, output value can be increased by more emphasis on customer’s requirement, variability can be reduced by reducing the number of steps involved in the design process; cycle times and most importantly continuous improvement can be built into the process.

3.4.2 Application of lean construction principles in construction planning Faniran et. al (1997) on the basis of extensive literature review and questionnaires have put forward a construction planning process plan which involves treating the planning process as a process which takes in inputs and gives construction plans as outputs. They have highlighted the fact that the construction planning process most prevalent today is that of developing a single plan and adhering to it for the entire duration. Those plans are seldom reviewed during the execution stage and the corrective actions only include adjusting the original schedules to actual performance. To improve the planning process they have suggested a shift towards contingency planning which includes preparation of several detailed plans prior to execution for different project environments. Hence the need to review the original plan for problems very seldom arises. To implement the contingency planning substantial amount of time and resources need to be expended during the construction planning prior to the execution and also in project control during construction work on site.

3.4.3 Application of lean construction principles in construction execution This stage involves utilization of the last planner tool (described earlier) of lean construction for execution of the project. In this section the meaning of the “pull process” for building up of the schedules and the workable backlog is described.

3.4.3.1 Phase scheduling Lean construction uses the pull technique for development of project schedules. Thereby only those tasks are scheduled and executed whose completion releases work to other tasks. This way, only the work that is required is done and thereby prevents any overproduction (Ballard 2000b). The phase schedules serve as a basis for the development of look-ahead schedules. In the phase scheduling process, representatives of all organizations involved in the phase sit down to decide on the work that must be performed to release work to other phases. The 26

people responsible for the work write their requirements on a sheet of paper and stick them on a wall in their expected sequence of performance. After all sheets are on the walls, the network diagram is prepared by moving and shifting of sheets. Thus new techniques and methodologies for doing the work are found out. After the finalization of the sequence of the activities, durations (without any float) are applied to them. The network diagram is then reexamined to look for processes which can be shortened. The earliest practical start date (calculated) for the phase is then determined by working backwards from the schedule. If there is any positive difference between the possible and the calculated start date that time can be allocates to critical processes in the phase to protect them from uncertainties. In case the difference is negative then the phase will have to be delayed and the time lost will have to be made up in other phases. 3.4.3.2 Look ahead process and Last Planner System Choo (Choo 2003) mentions that the Last Planner System developed by Ballard is a tool for workflow control while the weekly work planning is responsible for production unit control. The look ahead process involves the following processes: explosion; screening and make ready. Explosion: This involves exploding the activities mentioned in the master schedule to great details to identify all the pre requisites for the activity before it enters the look ahead window. Screening: This process is used for determining the status of tasks that are present in the look ahead window based on their pre requisites (constraints). Here we can choose whether to advance or postpone the tasks based on their status. Make ready: In this process the lead time (time for order to delivery) is estimated, the pre requisites are pulled and the work is executed. This process requires great caution as the ordering times have to be estimated reliably to prevent any inventory from building up at site. The status of the consuming activity should be matched with the ordering times of resources with great detail and caution. The make ready work then enters the workable backlog so that the scheduled work can begin. The work is monitored by using PPC (Percent of Planned Complete) and the inability to

27

achieve a high PPC is investigated for process improvement and to prevent the problems from re occurring. PPC: PPC or Percent of planned complete is the method used for monitoring of the project. Unlike the techniques of earned value estimate which is traditionally used for monitoring of projects, the PPC measurement has the following advantages: 1. Work is selected by the workers themselves and hence there is less chance of time over run. 2. The causes for the non completion of work are mentioned explicitly while analyzing PPC. 3. PPC helps in continuous improvement of the construction project as efforts are made to prevent the re occurrence of problems. PPC measurement is shown in Table 3.1. Table 3.1 PPC Measurement (Abdelhamid 2006) Week

1/1/2009

8/1/2009

15/1/2009

22/1/2009

PPC

50%

67%

80%

75%

Tasks Completed

2

2

4

3

Tasks Planned

4

3

5

4

1

1

Reasons for low PPC Engineering Weather

1

Pre requisite Labor

1

Materials Contract Equipment

1

28

CHAPTER 4

Identification of Wastes in Construction Process 4.1 Identification of Key Wastes and their Sources in Indian Construction Practices Phase 1 of the project involved the identification of key wastes in the Indian construction practices. As explained in the previous chapter, waste is any process which consumes resources without adding any value to the project. Lean construction aims to increase the efficiency of construction processes by either removing these wastes or reducing them to manageable levels. To identify the wastes in the construction practices at IIT Guwahati, a questionnaire-based survey, presented in the annexure, was conducted. The questionnaire was similar to that was employed in Chile for its construction sector by Alarcon (1997). The survey was carried out with the faculty and the engineers working at IIT Guwahati. The main aim of the questionnaire was the development of a cause effect matrix, which helped in identifying the major wastes and their corresponding sources of wastes and is shown in illustrated in Fig. 4.1. A total of 3 institutions/ companies took part in the survey namely: 1. IIT Guwahati 2. Gammon India Pvt. Ltd. 3. Punjj Lloyd Ltd. 4.1.1 Wastes in Construction Processes The activities presented in Table 4.1 were classified as wastes in the questionnaire (Alarcon 1997). 4.1.2 Sources of Wastes in Construction Processes The sources of wastes were grouped into three categories namely as shown in Table 4.2: Management related, Resources related and Information related (Alarcon 1997).

29

Table 4.1 Wastes in Construction Processes 1.

Work not done

2.

Unnecessary movement of materials

3.

Re-Work

4.

Excessive vigilance

5.

Unnecessary Work

6.

Extra supervision

7.

Defects

8.

Additional space

9.

Stoppages

10.

Delays in activities

11. Wastage of Materials

12.

Extra processing

13. Deterioration of Materials

14.

Clarifications

15. Unnecessary movement of labor

16.

Abnormal wear and tear of equipment

Table 4.2 Sources of Wastes in Construction Processes Management Related: 1. Unnecessary Requirement 2. Excessive Control 3. Lack of Control 4. Poor Planning 5. Excessive Red Tape Resources Related: 1.

Excessive Quantity

2.

Shortage

3.

Misuse

4.

Poor Distribution

5.

Poor Quality

6.

Availability

Information Related: 1. Unnecessary 2. Defective 3. Unclear 4. Late

30

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Sources of Waste MANAGEMENT RELATED Unnecessary requirement Excessive Management Control Poor Management Control Poor Planning Excessive Bureaucracy, paperwork RESOURCES RELATED Excessive amount Shortages Misuse Poor Distribution Poor Quality Availability Theft INFORMATION RELATED Unnecessary Defective Unclear Late

Wastes Uncompleted Work Rework Ineffective Work Defects Interruptions Materials Wasted Damaged Material Unnecessary Labor Movement Unnecessary Material Handling Excessive Surveillance Excessive Supervision Excessive Space Delays Extra Processing Clarifications needed Abnormal equipment wearing

Fig. 4.1: Cause Effect Matrix to determine the Main Sources of Wastes 4.1.3 Filling up of the Questionnaires The respondents were asked to identify at least six construction waste processes prevalent in their organization from the Table 4.1. After identification of the wastes they were asked to rank the wastes from 1 to the desired number (1 being the most serious). For the identification of the sources of wastes, the respondents were asked to mark the sources given in Table 4.2 with the rank of the waste. For e.g. if Rework was identified as a waste with a rank of 1 then all the sources corresponding to the waste Rework were to be marked as 31

1 in the 1st column. Similarly if Delays was identified as a waste with rank 2, then all sources corresponding to Delays had to be marked as 2 in the 2nd column. The same had to be repeated as per the number of wastes identified by the respondent. 4.2 Administering the Questionnaire Prior to the administration of the survey, a presentation was held (22nd September 2009, IIT Guwahati) which was attended by faculty members and engineers working at IIT Guwahati. The aim of the presentation was to introduce the topic of lean construction to the fraternity so that the waste processes in construction processes become conspicuous. A total of 23 participants attended the presentation. The questionnaires were given to all those present for the presentation and were sent to Gammon India Pvt. Ltd. and Punjj Lloyd Ltd. when they visited the IIT Guwahati campus. Out of the 30 questionnaires administered as hard copies 28 have been obtained. The break up is as follows: 1. IIT Guwahati – 20 2. Gammon India Pvt. Ltd. – 3 3. Punjj Llyod Ltd. - 5 The results and findings of the questionnaire survey are presented in the next chapter.

32

CHAPTER 5

Findings of the Questionnaire Survey and Discussion 5.1 General Out of the 30 questionnaires given to the participants of the survey, 28 responses were obtained. The results have been grouped under three categories: 1. IIT Guwahati 2. Gammon India Pvt. Ltd. and Punjj Llyod Ltd. 3. IIT Guwahati, Gammon India Pvt. Ltd. and Punjj Llyod Ltd. The above has been done to identify the wastes along with the sources of wastes for each company/institution. As the responses obtained from Gammon India Pvt. Ltd. and Punjj Lloyd Ltd. were less (3 and 5 in no. respectively), they could not be analysed separately. 5.2 Results for IIT Guwahati As observed from the pie chart shown in Fig. 5.1 and Table 5.1, delay in activities is the most significant waste that threatens the construction process accounting for 14 % of the total wastes in the responses, thereby indicating the criticality of this waste. Frequent rework is the second most critical waste affecting the construction process accounting for 12 % of the total wastes indicated in the survey responses. Another important waste highlighted in the responses is frequent interruptions in the ongoing activities which accounted for 10% of the total wastes mentioned by the participants of the survey. Defects also accounted for a significant proportion of the wastes with 9 % of the total wastes. The pie chart also highlights the waste - frequent clarifications needed which also accounted for 9 % of the total wastes, thereby indicating the need for better communication between all the parties involved in the project. Other wastes like ineffective work, unnecessary labor movement, uncompleted work and unnecessary material handling also accounted for a significant proportion of the total wastes mentioned by the respondents.

33

Table 5.1 Wastes and their Frequencies of Occurrence in the Responses (IIT Guwahati) Waste Categories Uncompleted Work Rework Ineffective Work Defects Interruptions Materials Wasted Damaged Material Unnecessary Labor Movement

Frequency Waste Categories 8 Unnecessary Material Handling 14 Excessive Surveillance 9 Excessive Supervision 11 Excessive Space 12 Delays 6 Extra Processing 7 Clarifications needed 10 Abnormal equipment wearing

Frequency 8 1 17 5 11 1

Fig. 5.1: Incidence of Waste Categories in form of a Pie Chart (IIT Guwahati) The cause-effect matrix for IIT Guwahati as shown in Table 5.2, points out the most important sources of the critical wastes, which were easily identified, based on their frequency of occurrence in the matrix, as follows: 1. Wastes - delay and interruption were caused majorly due to the absence of proper management control at the site along with poor planning. Shortage of resources was also equally responsible for the occurrence of this waste. This highlighted the fact that there was no scheduling / planning being done at the various sites and the work was carried out by the word of mouth. Another important fact to note was that the 34

subcontractors sometimes worked without any supervision of the site engineers and this highlighted the need for more management control. Also, in the absence of proper planning, the supply chain management at sites was erratic resulting in frequent material / resource shortage. 2. Rework was another waste which bothered the authorities here in IIT Guwahati. As obtained from the survey majorly the management related wastes along with poor quality of resources and unclear information contributed towards this waste. It was observed that there were frequent design changes at the sites which highlighted the need for proper planning before progressing on with the work; another important factor leading to this waste was excessive management control and unclear information. Also, in the absence of clear directives, the subcontractors were sometimes forced to do work which was not as per the design specified. It was also observed that at times work was carried out using substandard materials leading to frequent confrontations between the various parties involved in the project and ultimately resulted in rework and delays in the project. 3. The major sources of the waste - defect were usage of poor quality materials and incorrect / defective information. On further investigation it was found that incorrect information was sometimes passed onto the subcontractors from the management and this resulted in defects in the construction which later had to be reworked upon. 4. Another important waste highlighted in the survey – frequent clarifications needed – was attributed mainly to the absence of proper planning. It was observed that at times the management failed to obtain clear directives before starting the work and this resulted in the subcontractors seeking frequent clarifications during the course of the work. There was lack of proper planning before starting any activity. The other wastes like ineffective work, unnecessary labor movement were found to be considerably less significant when compared with the above mentioned wastes. Their sources were observed to be the absence of management control and proper planning at the site.

35


Sources of waste MANAGEMENT RELATED Unnecessary requirement Excessive Management Control Poor Management Control Poor Planning Excessive Bureaucracy, paperwork RESOURCES RELATED Excessive amount Shortages Misuse Poor Distribution Poor Quality Availability Theft INFORMATION RELATED Unnecessary Defective Unclear Late

Table 5.2 Cause Effect Matrix for IIT Guwahati

5 4 3 1 2 2 1 1 2 1

4 4 6 5 8 4 5 9 4

6 5 6 4 9 4 4 7 5

1 1

2 3 2 1 3 1

6 2 1 4 1 1 8 1 1 2 1 4 2 1

1 3 3 5 3 5 2 1 3

1 1 5 3 4 3 3 7 5

1 5 5 9 3 4 5 3 1

1 1 1 1 1 1 1 1 2 1

2 1 1 2 1 1

5 5 3 4 4

3

2 3 3 2

7 3 1 2

3 4 2 6 2 2 5 3 2 3 1 2 3 1 1 3 3

1

2 2 10 8 5 3 3 1 6 4 2 2 3 7 3 1 1

9 4 1 1 2 1

4 5 3 2 2 2 2 1 1 1

2 2 1 1 1

5.3 Results for Gammon India Pvt. Ltd. and Punjj Lloyd Ltd. Table 5.3 shows the frequencies of the wastes as obtained from the questionnaire. The most critical wastes are listed as under on the basis of their frequency of occurrence: 1. Interruptions 2. Delays, Rework and Uncompleted Work 3. Materials wasted, Unnecessary Labor Movement and Extra Processing 4. Defects The same can also be identified from Fig. 5.2 which shows the frequencies of wastes in the form of a pie chart. 36

Table 5.3 Wastes and their Frequencies of Occurrence in the Responses (Gammon India Pvt. Ltd. and Punjj Llyod Ltd.) Waste Categories Uncompleted Work Rework Ineffective Work Defects Interruptions Materials Wasted Damaged Material Unnecessary Labor Movement


Frequency 3 1 2 6 5 3 2

Fig. 5.2: Incidence of Waste Categories in form of a Pie Chart (Gammon India Pvt. Ltd. and Punjj Llyod Ltd.) The cause effect matrix for Gammon India Pvt. Ltd. and Punjj Lloyd Ltd. is shown in Table 5.4.

37



Table 5.4 Cause Effect Matrix for Gammon India Pvt. Ltd. and Punjj Lloyd Ltd.

2 2 1 1 2 1 1 1 1 1 1 2 1 1 1 1 2 2 1 1 1 0 1 2 1 1 1 1 1 1 2 1 2

2 1 1 1 1 2 1 1 1 2 1 2 2 2 1 1 1 0 2

2 1 1

1 1 1 1 2 1 0

1

1 1 1 1 1 1 1

3 2 1

1

1 1 1 2 1 1

1

1 1

1 1 1 1 1 1 2 1 0 2

1 1 1 1 1 2

From the cause effect matrix, the most important sources of wastes can be easily identified. For example, as obtained from the pie chart, the waste Interruptions is the most critical, hence we look into the row of the waste Interruptions, we can identify Unnecessary information as the most important source followed by poor planning and shortage of resources.

5.4 Results of IIT Guwahati Combined with Gammon India Pvt. Ltd. and Punjj Llyod Ltd. Table 5.5 shows the frequencies of the wastes as obtained from the questionnaire. The most critical wastes are listed as under on the basis of their frequency of occurrence: 38

1. Delays 2. Rework 3. Interruptions 4. Defects and Unnecessary Labor Movement The same can also be identified from Fig. 5.3 which shows the frequencies of wastes in the form of a pie chart. Table 5.5 Wastes and their Frequencies of Occurrence in the Responses (IIT Guwahati combined with Gammon India Pvt. Ltd. and Punjj Llyod Ltd.) Waste Categories Uncompleted Work Rework Ineffective Work Defects Interruptions Materials Wasted Damaged Material Unnecessary Labor Movement


Frequency 11 2 2 23 10 14 3

Fig. 5.3: Incidence of Waste Categories in form of a Pie Chart (IIT Guwahati combined with Gammon India Pvt. Ltd. and Punjj Llyod Ltd.) The cause effect matrix for IIT Guwahati combined with Gammon India Pvt. Ltd. and Punjj Llyod Ltd. is shown in Table 5.6. 39

Table 5.6 Cause Effect Matrix for IIT Guwahati combined with Gammon India Pvt. Ltd. and



Punjj Llyod Ltd.

2 6 1 3 2 3 1

2 4 6 5 6 6 6 6 5 4 3 9 11 1 4 4 5 4 2 10 9 2 1 4 5

2 3 3 1 4 1 1 2 1

1 1 2 1 1 1 1 2

1 1 1

1

1

2 4 11 9 6 3 3 1 7 5 2 3 5 7 3 1 1 3

8 2 5 1 10 1 2 4 1

2 4 3 5 3 5 2 3 3

1 3 5 3 4 4 3 7 6

1 5 5 9 5 5 5 5 2

2 1 1 2 3

2 2

9 5 1 1 1 3 1 1

5 3 2 3

6 3 3 2 2 1 1 1

1 2 3 2

2 1

1 2 1 1 5 1 1 1 2

6 6 4 4 4

4 1 3 2 6 2

3 3 4 2

8 3 2 2

4 4 6 4 4 3 1 2 4 3 2 3 3

2 3 1 1 2 1

From the cause effect matrix, the most important sources of wastes can be easily identified. For example as obtained from the pie chart, the waste Delays is the most critical, hence we look into the row of the waste Delays, we can identify Poor Management Control as the most important source followed by poor planning and shortage of resources.

40

CHAPTER 6

A Simplified Questionnaire for the Identification of Wastes in Construction Process 6.1 Need for a Simplified Questionnaire Although the earlier mentioned questionnaire survey was successful in its implementation in Chile and also here in IIT Guwahati, India, some problems were observed in the interpretation of wastes and their sources. The wastes delays and interruptions were found to have similar meanings and the respondents remarked that they had difficulties in differentiating between the two. They mentioned that interruptions led to delays and hence they should be grouped together. The respondents had similar difficulties while dealing with the waste defects, ineffective work, uncompleted work and rework; hence they should also be grouped together. Furthermore important waste categories from the point of view of Indian construction sector like space constrain and frequent changes in design were found to be missing from the questionnaire and should be incorporated in it. It was also observed that some sources of wastes relevant to the Indian construction practices like abnormal weather, equipment breakdown and accidents were missing and should be incorporated in it. Furthermore, the management related sources – unnecessary requirement and excessive management control were found to have similar meaning and hence should be grouped together. There were also suggestions on making the questionnaire more meaningful and less time consuming for the participants like keeping the questionnaire as a single performa instead of two seaparate performas. Based on the above mentioned feedback which was received from the participants a new simplified questionnaire has been formulated and presented in Table 6.3. The activities presented in Table 6.1 are classified as wastes in the questionnaire:

41

Table 6.1 Wastes in Construction Processes 1.

Delays / Interruptions

2.

Poor Quality Work / Rework

3.

Material Wastage

4.

Poor Quality / Damaged Material

5.

Unnecessary Labor Movement

6.

Unnecessary Material Handling

7.

Excessive Supervision

8.

Space constrain

9.

Frequent Changes in Design

10.

Extra processing

12.

Abnormal Equipment Wearing

11. Clarifications Needed

The sources of wastes are grouped into three categories as shown in Table 6.2: Table 6.2 Sources of Wastes in Construction Processes Management Related: 1.

Unnecessary / Excessive Management Control

2.

Poor Management Control

3.

Poor Planning

4.

Excessive Bureaucracy / Paper Work

Resources Related (including labor): 5.

Excessive Amount

6.

Shortage

7.

Misuse

8.

Excessive Transportation of Resources at site

9.

Poor Quality

10. Theft Information Related: 11. Unnecessary 12. Incorrect / Unclear 13. Late Unforeseen Situations Related: 14. Abnormal weather 15. Accidents 16. Equipment breakdown

42

6.2 Administering the Questionnaire The new questionnaire which has been formulated as shown in Table 6.3 consists of only one Performa, instead of the two separate Performas (presented in Appendix A1 and A2) used to conduct the survey, wherein the respondent only needs to identify the waste and its associated source with a tick. The questionnaire is itself in the form of a cause effect matrix so that the respondent can have a better understanding of the wastes and its corresponding sources. The relative criticality of any construction waste across a site can be gauged by taking responses from all the parties concerned with the project. After obtaining the required responses the occurrence of wastes and its corresponding sources can be summed up to obtain a cumulative bar / pie chart to efficiently identify the following: 1.

Relative criticality of waste affecting the construction and its corresponding sources. Relative criticality of the sources of wastes in the construction practices.

Although this questionnaire based survey approach can be used to identify the wastes prevalent across the entire Indian construction industry, but due to the heterogeneous nature of the industry which comprises of mainly small and medium scale firms (based on persons employed) a huge data set will be required from all parts of the country as there is a difference in construction practices across different regions and projects in India. Hence it is suggested that the questionnaire for identification of wastes in construction practices be administered on a case by case basis for the most successful implementation of lean construction.

43

Select waste category and its sources (Place a tick)

Sources of Waste

Wastes

Delays / Interruptions Poor Quality Work / Rework Materials Wastage Poor Quality / Damaged Material Unnecessary Labor Movement

Unnecessary Material Handling Excessive Supervision Space Constrain

Frequent Design Changes

Extra Processing Clarifications needed

Abnormal equipment wearing

44

INFORMATION RELATED

Equipment Breakdown

Accidents

Late UNFORSEEN SITUATIONS RELATED Abnormal weather

Incorrect / Unclear

Unnecessary

Theft

Availability

Poor Quality

Excessive transportation of resources at site

Shortages Misuse

Excessive amount

RESOURCES RELATED (incl. labor)

Excessive Bureaucracy, paperwork

Poor Planning

Poor Management Control

Unnecessary / Excessive Management Control

MANAGEMENT RELATED

Table 6.3: Questionnaire to Identify Wastes and their Sources

CHAPTER 7

Implementation of the Last Planner System in IIT Guwahati 7.1 Why the Last Planner System? As observed from the survey, the construction in IIT Guwahati is affected by delays, interruptions and rework, which have been attributed to mostly the management related sources like poor management control and poor planning along with shortage and poor quality of resources. After discussion with the faculty and engineers here in IIT Guwahati, it was decided to go for the implementation of the Last Planner System, (developed by Prof. Glenn Ballard) in IIT Guwahati, which is an integrated tool for the implementation of lean construction, to reduce the wastes thus identified. It was felt that since the Last Planner System is in essence a tool which promotes proper planning of the construction process and involves all the parties concerned with a construction project, it will help in mitigating the planning and management related wastes.

7.2 Selection of a Suitable Construction Site Construction is ongoing at a lot of sites in IIT Guwahati, however, for the implementation of the Last Planner System it was decided that such a construction site be identified which also involved works like that of electrical and plumbing apart from the regular civil works. This was done inorder to examine the potential of the Last Planner System to increase the cooperation among the different parties concerned with the project to expedite the construction process. The site thus identified was the construction of the extension of the Physics Department, IIT Guwahati. 7.3 Information about the Construction Site The site chosen was a 3 storey academic building covering an area of 865 sq.m per floor. The contract of the building was awarded to Buildrite Constructions of Guwahati at a cost of approximately Rs. 4.5 crores. At the time of starting the implementation of the Last Planner System it was estimated that the work will be handed over by 30/4/2010. The construction process at the site was labor intensive; no schedules were being followed or maintained at the 45

site. The construction was being done by word of mouth and by the use of previous experiences of the contractor. 7.4 Implementation of the Last Planner System The last planner system was formally started at the site on 20th December 2009. It was implemented as follows: 1. Creation of a milestone based Master Schedule for the remaining works. Since there was no schedule being followed at the site all the remaining activities till completion of the project were incorporated in the Master Schedule; the hand over date was taken to be 30/4/2010. 2. Selection of works to be completed in the coming 4 weeks were noted in the 4 Week Look Ahead Plan (Appendix B). On the basis of the master schedule thus developed, activities were selected which were to be completed in the coming 4 weeks. They were noted down in the prescribed format (Appendix B) along with their completion dates based on the prevalent conditions. 3. Identification of all prerequisites of the activities in the look ahead plan and their procurement. All the prerequisites (pending activities, labor requirements, material requirements, equipment, specifications etc.) of the activities listed in the look ahead were identified so that they can be procured / completed before starting the work. 4. Creation of a Weekly Work Plan (WWP) by selecting activities from the look ahead plan whose prerequisites had been procured (Appendix C). The activities for which all the resources had been procured were enlisted in the WWP and were required to complete in the coming week. 5. Weekly performance monitoring by calculating the PPC (Percent of Planned Complete) and taking necessary action to prevent reoccurrence of problems. This leads to continuous improvement. The activities in the WWP which had not been completed were noted along with the reasons for non completion so that they were not repeated again. As suggested by Ballard (2000b) the elements of the Activity Definition Model were used at the primary categories to provide a guide for reasons analysis that facilitated in identification of actionable causes.

46

The primary categories were directives, prerequisites and resources. Once placed within one of these categories, a plan failure was analyzed in accordance with the guidelines expressed in Figures 7.1-7.3. 6. The Steps 2 – 5 had to be repeated every week (Monday).

Fig. 7.1: Reasons Analysis Hierarchy – Directives (Ballard 2000b)

Fig. 7.2: Reasons Analysis Hierarchy – Prerequisites (Ballard 2000b) 47

Fig. 7.3: Reasons Analysis Hierarchy – Resource (Ballard 2000b) 7.5 Last Planner System Implementation Results – PPC Analysis The LPS system implementation results as shown in Table 7.2 and Fig. 7.4 show an uneven trend, beginning with an initial slump during the 1st week, PPC rises to 100 % in the 5th week only to fall back to 28 % in the following week. For the period 31/1/2010 – 7/3/2010 a PPC level of approximately 75 % was sustained, but beginning 7/3/2010 till the end of the project there was another slump. In the initial few weeks, a low PPC was understandable as that was a transition phase wherein the management was exposed to the idea of the LPS and the need for proper planning to eliminate / reduce the wastes observed from the questionnaire survey. Numerous efforts were made to make the management and the authorities aware of the LPS and the imminent benefits from its application, a number of site visits were there along with informal discussion with the site engineers and the subcontractors in order to make them comfortable with the idea of planning and scheduling of the project. It was observed that the site engineers got acclimatized to the LPS beginning the 5th week when a PPC level of 100% was reached. However, due to the sudden shortage of labor at the site, due to non-payment of dues, the PPC level for the following week dropped to 28 %. During the next month there was a considerable improvement in PPC due to the review meeting which was held on 22/1/2010 in 48

which all the major parties concerned with the project participated and took note of the prevalent situation. During the meeting all the wastes at the site were discussed, major among those were the problems of labor shortage due to non-payment of dues and cement shortage. It was decided that a stock of 50 bags would be maintained at the site and the accounting system for the wages of the labor would be improved to prevent a reoccurrence of such a situation. In the month of February the number of activities weekly allotted increased due to the commencement of the electrical works. The sub contractor handling the electrical work was extremely efficient and got adapted to the LPS very quickly. Among the different subcontractors working at the site, his performance was the best as he completed 16 tasks out of the 18 tasks which he committed to do during the period of the study. During the last month of the case study, labor problems became prominent at the site, it was observed that there was a continuous inflow and outflow of labor at the site. Major problems were noticed in the supply chain management of the contractor during this time. As the contractor was directly dealing with suppliers (no weekly meetings were held on site with the suppliers) there were repeated failures to procure the pre requisites on time and hence many activities remained in the look ahead schedule for nearly a month (MS box fixing and Window grills installation). Furthermore, many succeeding activities like internal plaster were also held up due to the non completion of the electrical works. In the last 2 weeks of the study, a sudden and severe cement shortage developed on site which lasted for 5 days leading to an extremely low PPC of 20% in the penultimate week. This problem was resolved in the following week after another major review meeting with the contractor; the contractor gave commitments to procure the pre requisites of the activities pending in the look ahead schedule during the last week, but again due to his “lack of seriousness” (as described to by the authorities here at IIT Guwahati), he was not able to keep majority of his commitments.

49

Fig. 7.4 PPC Variation The reasons for plan failures were classified as shown in Table 7.1 below. Table 7.1 Reasons for Plan failure Reasons Rain Prerequisite Design / Directives changed Equipment Labor Work started late Others

50

Table 7.2 PPC Analysis Week PPC Tasks completed Tasks alloted Reasons Rain Prerequisite Design / Directives changed Equipment Labor Work started late Other

20/12-27/12 16.67 1 6

27/12-10/1 50 4 8

10/1-17/1 16.67 1 6

4

2

3

Week PPC Tasks completed Tasks alloted Reasons Rain Prerequisite Design / Directives changed Equipment Labor Work started late Other

21/2 - 28/2 75 6 8

17/1-24/1 24/1-31/1 100 28.57 7 2 7 7

31/1-7/2 92.30 12 13

7/2-14/2 64.28 9 14

14/2-21/2 72.72 8 11

3 1

1 1

1 2 1

1 2

1/3-7/3 80 4 5

7/3-14/3 55.55 5 9

1

14/3-21/3 21/3-28/3 60 20 6 1 10 5

4

4

28/3-4/4 50 3 6

1

1 1

1

2 1

1 1

51

As shown in Fig. 7.5, failure to obtain pre requisites (materials) or complete the pre requisite activities by the allotted date and labor shortage were the main reasons for plan failure. Together they accounted for 76 % of the total reasons leading to plan failures. Ballard’s Activity Definition Model (Fig. 7.2 – 7.3) was applied to figure out the cause of the failures related to the above mentioned plan failures. In the first 2 weeks of the case study it was observed that some prerequisite related failures were due to the inability of the Last Planners to identify the all needed prerequisites, this was understandable as they were new to the concept of the LPS and needed some time to get used to it, some prerequisites were not identified in the weekly plans. The majority of the Prerequisite related failures were caused because the provider of the prerequisite failed to keep his promise. Hence, the prerequisites were not delivered on time and this led to failures in the plan. On further analysis it was found that the Last Planners were also partly responsible for some failures as they sometimes over committed beyond their abilities and hence were not able finish the allotted work. Majority of the Resources related plan failures occurred during the 2nd half of the study period. Labor shortage was experienced at the site and there was continuous inflow and outflow of labor from the site. It was observed that the sub contractors selected tasks for the work plan hoping that they would be able to get the labor before the start of the activity. This worked sometimes but in majority of the cases the labor was not available and this led to huge plan failures. Superficial labor shortage at the site was also reported due to non payment of the labor dues. Other factors like change in design or directives in the middle of the week and late starting of work together accounted for 13 % of the total plan failures. These failures occurred due to the lack of coordination between the authorities here at IIT Guwahati and the contractor and also because of the relative inexperience and lack of interest of the site engineers. As analyzed from Fig. 7.1 the design changes originated to incorporate the needs of the Physics department which were known very late into the work, there were also some directive changes in the middle of the week which highlighted the need for better coordination between the authorities and the contractor. Most potent design / directive changes originated because of the inability of the contractor to understand the needs of the project and failure to correctly interpret the directives from the authorities. The above mentioned factors had huge

52

consequences which led to a lot of and frequent rework at the site which could have been avoided through better coordination among all the parties of the project.

Fig 7.5 Reason Categorization 7.6 Problems Experienced during the Implementation of the Last Planner System 1. No planning / scheduling techniques were being followed at the site. 2. The construction wastes were mostly viewed as wastage of materials. 3. Lack of interest on the part of the contractor to implement the Last Planner System (Lack of adherence to the weekly schedules and the look ahead schedules.). 4. Lack of interest among all parties towards a joint weekly review meeting to monitor the progress of the work and to sort out the problems. This led to lack of coordination between the authorities and contractor. 5. There was excessive rework at the site due to the failure on the part of the contractor / site engineers to understand the requirement of the authorities. 6. There were acute problems in the supply chain management of the contractor, no effort was made to stick to the look ahead plan and order materials according to the date mentioned in it. This led to a huge buildup of activities in the look ahead plan.

53

7. There were problems of labor shortage at the site during the 2nd half of the study period. It was felt that the contractor failed to pay the labor properly and this led to frequent inflow and outflow of labor from the site. Superficial labor shortage was also reported when the contractor failed to pay the labor on time which led to stoppage of work.

54

CHAPTER 8

Conclusions, Recommendations and Future Work 8.1 Conclusions At the end of the project work the major objectives have been achieved. Phase I of the project work involved the identification of the key wastes along with their sources using a questionnaire based survey. As obtained from the analysis of questionnaires collected, Delays and Rework were the most critical wastes plaguing the construction practices. Their sources as found by the cause effect matrix shown in Table 5.2 lie in Poor Management Control, Poor Planning and Shortage of the Resources Used. Phase 2 of the project involved the implantation of the Last Planner System at the extension of the Physics Department to reduce / remove the wastes identified from the survey. Although the wastes could not be removed completely, they were made conspicuous and were documented. The PPC level ranged from 16.67 % to 100 % with an average PPC of 55.84% for the duration of the study. It was observed that much more improvement could have been achieved if the contractor would have taken keen interest in the implementation of the LPS. There was also lack of interest among all the authorities to sit for a weekly review meeting to solve the problems causing the plan failures. But nevertheless, a feedback mechanism has been setup in IIT Guwahati which can be used to track the work progress and identify the problems affecting the construction process. It is hoped that this mechanism be implemented at all sites of IIT Guwahati and all parties take interest in the implementation of the LPS to realize its benefits. 8.2 Recommendations The following recommendations are made on the basis of this research to improve the construction scenario here in IIT Guwahati if the work is going to be done by local contractors: 1. Weekly review meetings at all sites (1 site per day) in which all parties sit down and review the work done in the previous week, solve the problems to prevent reoccurrence, make look ahead plans and weekly plans using the LPS.

55

2. As the Engineering cell is understaffed at the moment, it is recommended that a dedicated project management team be formed which will maintain the weekly plans to keep track of the project and organize the review meetings. 8.3 Future Work As the implementation of the LPS was not completely successful owing to a host of reasons discussed in Chapter 7, it is hoped that the LPS be applied again to another construction site taking into consideration the problems faced while implementing it for this project. The only major problem which lies in the way is to make the people concerned change their mindset and be open to new ideas about managing the construction projects.

56

References 1. Abdelhamid,

T.

(2006),

“Lean

Construction

Principles

and

Methods”,

(Aug. 31, 2009). 2. Abdullah, F. (2003), “Lean manufacturing tools and techniques in the process industry with a focus on steel”, Dissertation, University Of Pittsburgh. School Of Engineering, U.S.A. 3. Alarcon, L.F. (1997), “Tools for the identification and reduction of wastes in construction projects”, Lean Construction, A.A.Balkema, pp. 365 – 377. 4. Ballard G. & Howell G. (1997a), “Implementing Lean Construction: Stabilizing work flow”, Lean Construction, A.A.Balkema, pp. 105. 5. Ballard G. & Howell G. (1997b), “Towards construction JIT”, Lean Construction, A.A.Balkema, pp. 297. 6. Ballard, G. and Koskella, L. (1998), “On the Agenda of Design Management”, Proceedings of 6th Annual Lean construction Conference, Brazil. 7. Ballard, G. (2000a), “The Last Planner System of production control”, Dissertation, University of Birmingham, England. 8. Ballard, G. (2000b), “Phase Scheduling”, LCI White Paper. 9. Bhasin, S & Burcher, P (2006), “Lean Viewed as a Philosophy.” Journal of Manufacturing Technology Management, 17(1), pp. 56-72. 10. Choo, H.J. (2003), “Distributed Planning and Coordination to Support Lean Construction”, Dissertation, University of California, Berkeley, America. 11. Faniran, Oluwoye and Lenard (1997), “Application of the lean production concept to improving the construction planning process”, Proceedings of the 5th Annual Lean construction conference, Gold Coast, Australia. 12. “India: Indian Road Construction Industry Capacity Issues, Constraints & Recommendations.” World Bank Report no. 46326-IN, November 2008. 13. Kartam, S., Ballard, G. and Howell, G. (1997), “Construction Models: A new integrated approach”, Lean Construction, A.A.Balkema, pp. 389. 14. Koskella, L. (1997), “Lean Production in Construction”, Lean Construction, A.A.Balkema, pp. 1. 15. Koskella L. (1998), “Lean Construction”, VII Encontro Nacional de Technologia do Ambiente Construido, Universidade Federal de Santa Catarina, Chile. 57

16. Krafcik, John F. (1988). "Triumph of the lean production system". Sloan Management Review, 30 (1): pp. 41-52. 17. Laskar A. and Murty C. V. R. (2004). “Challenges before Construction Industry in

India.” Proc., 7th National Conference on Construction, New Delhi, India. 18. Liker, Jeffrey K. (2004a), “The TPS House Diagram: A system based on a structure, Not just a set of techniques”, The Toyota Way, McGraw Hill, pp. 33. 19. Liker, Jeffrey K. (2004b), “Using the Toyota Way for Long - Term Success.” The Toyota Way, McGraw Hill, pp. 27. 20. Liker, Jeffrey K. (2004c), “The Heart of the Toyota Production System: Eliminating Waste”, The Toyota Way, McGraw Hill, pp. 28-29. 21. Liker Jeffrey K. (2004d), “The Heart of the Toyota Production System: Eliminating Waste”, The Toyota Way, McGraw Hill, pp. 21. 22. Liker Jeffrey K. (2004e), “How Toyota Became the World’s Best Manufacturer: The Story of the Toyoda Family and the Toyota Production System”, The Toyota Way, McGraw Hill, pp. 15. 23. Liker Jeffrey K. (2004h), “The 14 Principles of Toyota Way”, The Toyota Way, McGraw Hill, pp. 37-41. 24. “MAMTC – Traditional vs Lean 2009”. (August 31, 2009) 25. Melles, B. (1997), “What do we mean by Lean Production in Construction?”, Lean Construction, A.A.Balkema, pp. 11. 26. Ohno, T (1988), “The Toyota Production System: Beyond Large Scale Production.” Productivity Press. 27. Serpell, A., Venturi, A., and Contreras, J. (1997), “Characterization of waste in building construction projects”, Lean Construction, A.A.Balkema, pp. 68. 28. Tzortzopoloulos, P and Formoso, C.T (1999), “Considerations of Application of lean construction principles to design management”, Proceedings of the 7th IGLC, Berkeley, USA. 29. Womack, James P and Daniel T. Jones (2003). Lean Thinking, Free Press, pp 352. 30. Womack J., Jones D. and Roos T. (1990a), “The Origins of Lean Production”, Machine That Changed the World, MacMillan-Canada, pp. 26-33. 31. Womack J., Jones D. and Roos T. (1990b), “The Rise of Lean Production”, Machine That Changed the World, MacMillan-Canada, pp. 48-49.

58

32. Womack J., Jones D. and Roos T. (1990c), “The Rise of Lean Production”, Machine That Changed the World, MacMillan-Canada, pp. 51-52. 33. Tanskanen, K., Wegelius, T., Nyman, H. (1997), “New tools for lean construction”, Lean Construction, A.A.Balkema, pp. 336-337.

59

Appendix A. Questionnaire Used for Identification of Wastes and their Sources in Construction Practices

1

NAME

2

POSITION i ii iii iv

Resident Engineer General Foreman Administration Others

3

COMPANY

4

TYPE OF PROJECT i High Rise Building ii Other Buildings iii Highways & roads iv Industrial v Mining vi Civil vii Others

60

(pls. specify)

(pls. specify)

Instructions for filling up of the questionnaire 1.

2.

3.

Please start filling the questionnaire from A.1 Order the waste categories as per their importance. E.g. if rework is the most affecting waste in your organization then mark it as 1 and move to other wastes ranking them as 2, 3 and so on. Corresponding to each waste category please identify the sources of waste in your organization. E.g. if rework has been marked as an affecting waste with rank 1 then please identify all sources corresponding to that waste and mark them as 1. Similarly if Defects have been given rank 2 then identify all sources of wastes corresponding to the waste category Defects and mark them as 2. If you find any waste category missing or any source of waste missing then please indicate them in the space provided in the questionnaire and mark your choices appropriately.

A .1 Please m ake an assessm ent of the frequent w aste categories in your w ork environm ent 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Uncompleted Work Rework Ineffective Work Defects Interruptions Materials Wasted Damaged Material Unnecessary Labor Movement Unnecessary Material Handling Excessive Surveillance Excessive Supervision Excessive Space Delays Extra Processing Clarifications needed Abnormal equipment wearing Others: Please specify in the space below

61

A .2 Please m ake an assessm ent of the sources of w aste in your organization MANAGEMENT RELATED 1 Unnecessary Requirement 2 Excessive Management Control 3 Poor Management Control 4 Poor Planning Excessive Bureaucracy, 5 paperwork RESOURCES RELATED 1 Excessive amount 2 Shortages 3 Misuse 4 Poor Distribution 5 Poor Quality 6 Availability 7 Theft INFORMATION RELATED 1 Unnecessary 2 Defective 3 Unclear 4 Late If there are more sources of waste in your organization then please mention in the space below

62

B. Performa used for creating the 4 weeks Look ahead Schedule

63

C. Performa used for creating the Weekly Work Plan

64

Implementation of Lean Construction in IIT Guwahati

Implementation of Lean Construction in IIT Guwahati

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