effect of corn starch on cinder-jute concrete

EFFECT OF CORN STARCH ON CINDER-JUTE CONCRETE MOHAMMED TABREZ AHMED1, BHARGAVI Y N1, ABDULLAH1, POOJA R1 ANAND KUMAR G2 ABSTRACT: Admixtures are used to alter the properties of concrete. Admixtures are substances introduced into a batch of concrete during or immediately before its mixing. There are numerous benefits available through the use of admixtures such as improved quality, colouring, greater concrete strength, increased flow for the same watercement ratio, enhanced frost and sulphate resistance, improved fire resistance, cracking control, acceleration or retardation in setting time, lower density and improved workability. The specific effects of an admixture generally vary with the type of cement, mix proportion and dosage. Starch can be used in concrete as an admixture, densifier and pozzolana. In this particular study corn starch is used in light weight cinder concrete reinforced with raw jute fibres. The workability of concrete is tested using slump test. The starch is added for testing with percentages 0.5, 1 & 1.5 by the weight of cement in cinder-jute concrete. The workability of cinder-jute concrete decreased with the addition of corn starch. The addition of corn starch decreased the density of cinder-jute concrete. Compressive strength of cinderjute concrete decreased with the addition of corn starch, it is minimum with the addition of 1% of corn starch and maximum with 0.5%. Therefore, Corn starch cannot replace the use of chemical admixtures because the results are decreasing with its use in cinder-jute concrete. Keywords: concrete admixture, corn starch, cinder-jute concrete, light weight concrete, jute fibres

I.

INTRODUCTION:

History of admixture is as old as history of concrete. it embraces a very vast field, but a few types of admixtures called water reducers or high range water reducers generally referred to as plasticizers and superplasticizers, are of recent interest. These were specially engineered in japan and Germany around 1970s and later on made popular in USA, Europe, Middle and far East countries. In India the use of admixtures started around 1985. Admixtures are incorporated into concrete in today’s world in order to achieve variety of goals. This in effect improves the properties of fresh and hardened concrete. The effect of these admixtures on properties of concrete depends for example on a lot of factors such as functional groups, chemical configuration and molecular weight (Ouyang et al., 2009).

1. 8 sem, civil department, Impact college of engineering and applied sciences 2. assistant professor, civil department, Impact college of engineering and applied sciences

Continuous changes in the requirements for high strength and durable concrete structures interwoven with economic considerations necessitate intense search for materials and products. In recent times research efforts have been focused on recycled materials. Renewed efforts are also being concentrated on research into varieties of admixtures since for obvious reasons they enhance properties of fresh and hardened concrete. Major admixtures used for cementitious based systems are oil based and are non-renewable materials with potential for pollution such as formaldehyde (Zhang et al., 2008). With the development of green concrete in recent times there is the need for development of bio-based admixtures that may perform as equally well as oil-based polymers used as admixtures, hence the use of starch. Xing et al. (2006) and Crepy et al. (2011) noted that starch is one of the most abundant polymer resources in the world and have comparable performance of starch and starch derivatives in their dispersing ability with petrochemical polymers. Starches and its derivatives are known to exhibit viscosity modifying characteristics. A major advantage of starch is that it is a renewable material that has varieties of industrial applications because it is inexpensive and environmentally friendly. Starch derivative is an anionic material that has been used as filmforming agent for coating seeds, super absorbents, as adhesive in the paper industry and drug carrier. The use of starch and starch derivatives as viscosity modifying admixture in cementitious systems have been reported in recent times. However, the behaviour of the polymers in cementations systems may vary depending on a lot of parameters. This project is experimental work to find out the effect of corn starch on jute fibre reinforced light weight concrete using cinders as light weight aggregate.

II.

EXPERIMENTAL DETAILS: 1. MATERIALS USED:

Starches can be used as pozzolana, densifiers, setting time retarders etc., Corn starch is locally available and hence it was obtained. It had the specific gravity of 1.465. Portland Cement of brand name RAMCO cement of grade 53 was used with Sp. gravity 3.15. In this project polymer-based admixture named “CONPLAST” is used whose Specific gravity was given as 1.07 in its specification. Jute fibres of 0.5mm Optimum length was cut and used. Specific Gravity was 1.48. Table 1 - properties of gravel, cinders, sand, jute and corn starch. PROPERTY

GRAVEL

CINDERS

Colour

Whitish Grey

Black

Shape of gravel

Angular

Nominal size specific gravity Water absorption

20mm 2.635 1.2%

Angular with sharp edges 20mm 2.07 3.97%

SAND Golden yellow

zone 3 2.59

2. Concrete mixes Normal concrete and modified with cinder, jute and corn starch contents are listed in table 2. Table 2 - the mix proportions calculated Mix

Name given

RATIO

Normal Mix

N

1: 1.29: 2.9

25% cinder replaced

C

1:1.29:2.18:0.57

Cinder replaced and with 1% jute

CJ

1:1.28:2.17:0.57

0.5%

CJC1

1:1.28:2.17:0.56

1%

CJC2

1:1.28:2.16:0.56

1.5%

CJC3

1:1.27:2.16:0.56

1%

CJC4

1:1.27:2.16:0.56

cinder, jute and corn starch With cinder, jute and chemical

III.

TESTS PERFORMED: 1. SLUMP TEST:

This test was performed according to IS 1199 – 1959, to find the workability of concrete mix for water cement ratio 0.45 Table 3 - slump test values w/c ratio 0.45 1 2 3 Average

N

C

CJ

CJC1/2/3

CJC4

38 42 41 40

22 27 24 25

8 12 9 10

0 0 0 0

18 23 17 20

slump in mm

SLUMP VALUES 45 40 35 30 25 20 15 10 5 0 N

C

CJ

CJC1/2/3

CJC4

Type of concrete mix trail 1

trail 2

trail 3

Average

Graph 1 - Comparison of Slump Results 2. COMPRESSION STRENGTH TEST: The test is conducted based on IS standard as per IS 516:1959. Specimen of size 150*150*150mm have been set up for testing the compressive quality of cement. Table 4 - weights of cubes used for compression strength test Cubes 1 2 3 Average

N

C

CJ

7970 7920 8180 8023

8150 7950 7980 8026

7910 8130 8040 8026

CJC1 CJC2

CJC3

CJC4

7750 7840 7820 7803

7760 7520 7680 7653

7880 8140 7960 7993

7840 7760 7810 7803

WEIGHT OF CUBES 8400

weight in grams

8200 8000 7800 7600 7400 7200 7000 N

C

CJ

CJC1

CJC2

CJC3

CJC4

Type of concrete mix cube 1

cube 2

cube 3

Average

Graph 2 comparison of weights of cubes used for compression strength test

Table 5 - Compressive strength of cubes

Cubes 1 2 3 Average

N

C

CJ

CJC1

CJC2

CJC3

CJC4

41.54 40.33 42.8 41.55

43.11 40 40.44 41.18

36.44 60 42.22 46.22

47.55 30.66 41.33 39.84

43.55 32 37.77 37.77

40.44 36.44 40 38.96

34 37.77 42.8 38.19

compressive strength in N/mm2

COMPRESSIVE STRENGTH 70 60 50 40 30 20 10 0 N

C

CJ

CJC1

CJC2

CJC3

CJC4

Type of concrete mix cube 1

cube 2

cube 3

Average

Graph 3 comparison of compression strength of cubes 3. SPLIT TENSILE TEST: The test is conducted based on IS standard as per IS 516:1959. Specimen of size 150 mm diameter and 300mm height have been set up for testing the compressive quality of cement. Table 6 - weights of cylinders used for splitting tensile strength test cylinder 1 2 3 Average

N 1225.0 1214.0 1228.0 1222.3

C 1247.0 1256.0 1235.0 1246

CJ 1243.0 1220.0 1211.0 1224.6

CJC1 1212.0 1218.0 1216.0 1225.3

CJC2 1232.0 1232.0 1230.0 1231.0

CJC3 1223.0 1217.0 1219.0 1219.6

CJC4 1207.0 1239.0 1290.0 1245.3

WEIGHT OF CYLINDERS weight in grams

1260 1240 1220 1200 1180 N

C

CJ

CJC1

CJC2

CJC3

CJC4

Type of concrete mix cube 1

cube 2

cube 3

Average

Graph 4 comparison of weights of cylinders used for splitting tensile strength test Table 7 - Splitting tensile strength of cylinders cylinder

N 3.466 3.678 2.33 3.158

1 2 3 Average

C 3.456 3.74 3.38 3.52

CJ 3.466 3.89 3.678 3.678

CJC1 3.04 3.678 3.389 3.359

CJC2 3.536 3.536 3.524 3.536

CJC3 3.74 3.11 3.35 3.425

tensile strength in N/mm2

SPLITTING TENSILE STRENGTH 5 4 3 2 1 0 N

C

CJ

CJC1

CJC2

CJC3

CJC4

Type of concrete mix cube 1

cube 2

cube 3

Average

Graph 5 comparison of splitting tensile strength of cylinders

CJC4 3.74 3.11 3.6 3.48

IV.

DISCUSSION:

For water cement ratio 0.45 true slump was achieved and even this decreased on the addition of cinders due to its more porous surface and then with jute due to its more water absorption and more due to addition of corn starch because corn starch acted a densifier. To increase the slump and hence workability w/c ratio may be increased which on the other hand may decrease the strength of the concrete or admixtures free from formaldehyde or other natural admixtures may be used which does not effect the environment either before, in its life or after demolition of the structure which is the primary aim of this investigation. The weight of cubes decreases with the addition of corn starch to the concrete.The weight of the cylinders decreases with the addition of corn starch in the cinder jute concrete. The compressive strength of normal concrete meets the target strength of the concrete i.e., 41.55 N/mm2 as the result does not lie below 5% of 43 N/mm2. The compressive strength decreased a little on addition of cinders but increased drastically on the addition of jute to cinders. When to this corn starch and chemical admixture was added the strength started decreasing. The splitting tensile strength increases on the replacement of cinders and further increases on the addition of jute as reinforcement to the cinder mixed concrete. Tensile strength started decreasing on the addition of admixtures it was minimum at 0.5% corn starch and max at 1% corn starch.

V. CONCLUSION: 1. For water cement ratio 0.45, true slump (40mm) was achieved and this decreased on the addition of cinders due to its porous surface. When jute was added to cinder concrete slump was reduced due to its more water absorption property and slump decreased more on the addition of corn starch due to its densifying property. 2. The compressive strength of normal concrete (41.55 N/mm2) met the target strength of the concrete calculated (43 N/mm2), the result is within 5% of target strength. The compressive strength increased on the addition of jute to cinder concrete. When to this, corn starch or chemical admixture was added the strength started decreasing. 3. The splitting tensile strength increased on the replacement of cinders and further increased on the addition of jute. Tensile strength started decreasing on the addition of admixtures, it was minimum at 0.5% corn starch and max at 1% corn starch and there was no considerable increase in strength when chemical admixture was used. 4. There is an increase in strength when jute is added to cinder concrete, therefore, cinder-jute concrete can be efficiently used in building construction. 5. There is decrease in strength and workability when corn starch is used in the cinder-jute concrete but weight of concrete is reduced i.e., corn starch mixed concrete is lighter in weight than the cinder-jute concrete due to its densifying action. 6. Cinder-jute concrete gives more strength than corn starch mixed concrete.

REFERENCES: 1. Akindahunsi et al. in his research in 2015, titled “Strength and durability properties of concrete with starch admixture”. 2. Suhad M Abd, Qasssim Y Hamood, Alaa S Khamees and Zainab H Ali, “Effect of Using Corn Starch as Concrete Admixture”. IJERST, Volume 5 (2016) pp 35-44 3. GK Patel & SV Deo, “Parametric Study of Natural Organic Materials as Admixture in Concrete”. IJAER volume 11 (2016) pp 6271-6277 4. E.Hanuman Sai Gupta, V.Giridhar Kumar, “Investigations on Properties of Light Weight Cinder Aggregate Concrete”. IJERD volume 11 (July 2015) pp 50-59 5. Dastagir Y and Dadapeer A.B.S, “strength analysis of concrete by using cinder aggregate” in volume 5, issue 12, dec 2016, IJIRSET. 6. Gopi Raval and Maulik kansagra, “effect of jute fibres on fibre-reinforced concrete” IJIER, volume 4, issue 8 (2017) pp 7-12 7. T. Sai Vijaya Krishna and B. Manoj Yadav, “a comparative study of jute fibre reinforced concrete with plain cement concrete”. IJRET volume 5, issue 9 (Sep 2016) pp 111-116 8. Pooja Warke and Shringala Dewangan, “evaluating the performance of jute fibre in concrete”. IJTRD volume 3, (May-June 2016) pp 371-373 9. The project “development of jute fibre reinforced cement concrete composites” JMDC/JTM/MM-IV/2008, by MIT and sponsored by national jute board, ministry of India. 10. Priyanka Goel, Mohd. Usman and Sandeep Panchal, “experimental study of jute fibre reinforced concrete” ICETETSM-17 pp 593-598