Overloading and Road Management Report from JICA

Overloading and Road Management

Report from JICA 2nd Asia regional Congress Executive Session -2 Oct. 17, 2016 at Kuala Lumpur, Malaysia

Yukinari TANAKA Financial Cooperation Implementation Dept.

Report from JICA

Contents 1. Increasing heavy trucks & overloading 2. Damages caused by heavy trucks 3. Countermeasures against those damages 4. Key questions 5. Questionnaire and answers

1. Increasing heavy trucks & overloading  Goods movement increases with the economic growth in many developing countries, and which brought about rapid increase in heavy trucks.  17 countries from Asia, 22 countries from Africa have performed more than 5 % economic growth in 2013.  Development of modern road network and automotive industries enabled introduction of very heavy trucks. Could be more than 34 tons; (Tanzania, Africa) ⇒

 Increasing Axle load

Axle load (tonf)

(Belgian data)

Axle load distribution between 5 tons to 10 tons increased much and the average damage factor per truck increased two times (PIARC ‘Bituminous Materials with anhigh resistance to flow rutting’ 1995).

 Rapid Increase of number of Vehicles in Developing Countries Import

Increasing rate 22.8% between 2005 and 2012

-0.1 % Increasing rate of vehicle in a decade

(by Ingerosec Corp.)

Vehicle importation in Tanzania

 Increase of heavy vehicles in Southeast Asian Countries Number of heavy vehicles are beginning to increase rapidly.

2. Damages caused by heavy trucks Very heavy and slow vehicles on the slope section (Ethiopia, Africa)

Overloaded truck; Caring cement with total weight of more than 70 tons (Tajikistan, Central Asia)

2. Damages caused by heavy trucks (cont.) Serious rutting on the climbing section. (Ethiopia, Africa)

Alligator crack on the wheel truck supposed to be developed by very heavy trucks. (Lao PDR)

2. Damages caused by heavy trucks (cont.) Traction & breaking force of heavy trucks can cause slippage of surface layer of pavement. (Tajikistan, Central Asia)

Platooning heavy vehicles (Tajikistan, What Asia) brought about Central

this? 9

2. Damages caused by heavy trucks (cont.) Heavy trucks destroy to the bottom of pavement.(Lao PDR)

Pot holes developed associated with poor base & subbase drainage and heavy vehicles. (Ethiopia, Africa)

2. Damages caused by heavy trucks (cont.) Old Bridges can’t stand without temporary support piers because of very heavy vehicles. (Lao PDR)

A big truck carrying copper ingot which is under legal weight limit but still very heavy.

 Not only by overloading but by coming into wide use of large trucks, road administrator reinforces the existing bridges.

2. Damages caused by heavy trucks (cont.) Overloaded HGVs, equivalent to 0.3% of total traffic volume, causes 90% of the total damage on of highway bridges in Japan. 1. According to the experiment results conducted by the national government, etc., damage on reinforced concrete slabs of highway bridges increase in proportion to the weight with 12th power. 2. The Impact of a truck with 20-ton axle load on highway bridge is equivalent to the 4,000 vehicles with 10-ton axle load. 【Figure : Damage on of highway bridges】

Traffic volume ←Overloaded HGVs

Non overloaded HGVs

Overloaded HGVs

Non overloaded HGVs

Scale of Damages

Calculated by the data of automatic measurement device at 39 places : from MLIT, Japan

2

2. Damages caused by heavy trucks Heavy trucks often cause serious traffic accidents.

Carrying rose wood lumber estimated to be more than 120t.

3. Overloading Control & Strengthening Pavement Overloading & JICA  JICA is supporting those governments which is planning to control overloading by not only providing weigh stations but also total traffic management know-how.

Weighing what?? Weigh station in Tajikistan

 To realize appropriate road maintenance and traffic management, overloading control is one of the most important issue to be solved.

3. Overload Control & Strengthening Pavement (Cont.)

In one case, the contractor of the JICA project supports the government to operate weigh station to prevent the damage caused by those overloaded trucks after the completion of the new road.

3. Overload Control & Strengthening Pavement (Cont.) Pavement and JICA  To provide better connectivity by providing better roads is the final goal of JICA as an international cooperation organization.  JICA is preparing a manual for asphalt pavement to solve recent pavement problems which JICA is facing.  Plastic rutting is the major concern of quality control as many road projects are going on in the tropical area.  Though introduction of modified asphalt or cement concrete pavement is necessary for the road section of very heavy and slow traffic, we have to make the most of potential performance of straight asphalt.

3. Overload Control & Strengthening Pavement (Cont.)  In addition to the Marshal Test Method, introduction of a gyratory compactor and wheel test are effective tools to design rut-resist asphalt mix.

Wheel tracking test machine (basic model)

Gyratory compactor

3. Overload Control & Strengthening Pavement (Cont.) Comparison with several standards regarding DS(Dynamic Stability gained by wheel trucking test) DS

DS

（ count/mm）

（ count/mm） Traffic C in

3,000

3,000 Modified Ac

OKINAWA

Modified Ac

1,500

1,500 Traffic B in OKINAWA Straight Ac

800

800 5,000 LEGEND

500

Te ch . Stan d ard

M LIT, Jap an

Straight Ac

De sign Gu id e lin e in NEX C O

(Traffic vo lu me :o n ly 1 st ye ar)

Ove rlappe d are a Propos ition from the surve y in OKINAWA (designa ted Ac)*

250

1,000 1,500

3,000

*Regarding Okinawa, data studyed by Okinawa General Bureau

Heavy Traffic Volume (count/day direction)

3. Overload Control & Strengthening Pavement (Cont.) International Cooperation  Besides JICA’s contribution to the better connectivity, Japanese government and ASEAN is running a Joint Research on Road Technologies for ASEAN CrossBorder Corridors.  Pavement and traffic is the major concern of the joint research, and international cooperation to solve the common issue is inevitable for development of the region as a whole.

４. Key questions (1) Increasing very heavy trucks and overloading have been observed world worldwide. What is going on in your country? (2) Isn’t various types of damages arising on pavement and bridges because of stress caused by those heavy and overloaded vehicles? (3) Aren’t we lacking various basic traffic data such as axle load of trucks to analyze and discuss overloading control and proper pavement design? (4) Even after the success of controlling overloading, we have to cope with modern heavier traffic to cater developing economy. What can we do to improved pavement design, to improve road maintenance? For example;  Collection of axle load data utilizing “WIM”  Establishing standard design method of ant-rut asphalt  Improving cement-concrete pavement engineering…….

5. Questionnaire and answers (1) Basic data (2) Control of overload vehicles (3)Traffic management and structural design including pavement