Effect of rice husk ash on the strenght and durability of concrete by debasree

50 %
50 %
Information about Effect of rice husk ash on the strenght and durability of concrete by...

Published on October 13, 2016

Author: DEBASREEGHOSH1

Source: slideshare.net

1. EFFECT OF RICE HUSK ASH ON THE STRENGTH AND DURABILITY PROPERTIES OF CONCRETE NATIONAL INSTITUTE OF TECHNOLOGY AGARTALA DEBASREE GHOSH JUNIOR ENGINEER (CIVIL DEPT) WORK OF 2014-8TH SEM

2.  Chapter:1- Introduction  Chapter:2- Objective  Chapter:3- Literature Review  Chapter:4- Material Properties  Chapter:5- Experiments required to observe the effect  Chapter:6- Observation  Chapter:7- Conclusion.  Chapter:8- Future Scope  References

3.  Concrete is the most vital material in the modern construction.  RHA (RICE HUSK ASH) Concrete is the special type of concrete, that are produced by unusual techniques. Concrete is by definition a composite material consisting essentially of a binding medium and aggregate particles with definite proportion of water and it can take many forms.  RHA Concrete do have advantages as well as disadvantages. The character of the concrete is determined by quality of the paste. That is its workability. Cont…

4. CONCRETE COARSE AGGREGATE FINE AGGREGATE BINDING MATERIAL WATER Cont…

5. CEMENT LIME LIME- CEMENT BINDING MATERIAL COARSE AGGREGATE STONE BRICK CHIPS Cont…

6. SAND STONE DUST RHA SURKHI CINDER FINE AGGREGATE Cont…

7.  Effect of Rice Husk Ash depends on the amount of replacement and on the chemical and physical characteristic of replaced material.  Here we will introduce Rice Husk Ash as a replacement of Fine aggregate with different percentages.  Investigations for the requirement of water for different percentages of RHA, amount of replacement and the change in the behaviour of concrete is done.

8.  During the milling of paddy about 22 % of the weight of paddy is received as husk. This husk is used as fuel in the rice mills. This husk contains about 75 % organic volatile matter which burns up and the balance 25 % of the weight of this husk is converted into ash during the firing process, which is known as rice husk ash (RHA).  It is highly reactive in nature and obtained by combustion process. Cont…

9.  It is a part of waste ashes. The landfill of waste ash is a problem of environmental effects because these waste ashes are not used in any work without construction.  It is a green house agent and increases the green house effect adversely and becomes non-eco friendly. Many researches had been done to find out its solution. Cont…

10. What we should do? LET US OBSERVE BY EXPERIMENTAL WAY

11.  RHA has two roles in concrete manufacture, as a substitute for fine aggregate, reducing the cost and weight of concrete in the production of low cost building blocks.  Therefore, a large number of researchers have been directed toward the utilization of waste materials.  It increases the durability of concrete. Cont…

12.  Rice Husk Ash (RHA) is an agricultural waste product, and how to dispose off it is a problem to waste managers. Use of RHA reduces this type of problems.  As it is a waste form in environment there is an increasing importance to preserve the environment in the present day world. RHA from the parboiling plants is posing serious environmental threat and ways are being thought of to dispose them. Cont…

13.  Therefore some research work has been done and found that RHA can be used in construction purpose as a replacement for cement and sand.  The concrete material is the expensive material and used in all over India, if all-important expensive material is partially replaced with more natural, local and affordable material like RHA will not only take care of waste management but will also reduce the problem of high cost of concrete and housing. Cont…

14.  RHA can be used for low cost building (say less important building specially). But in some specified amount of RHA can be used.  It is also found that RHA, fly ash with some steel fibre shows better strength properties than normal concrete.  By using this Rice husk ash in concrete as replacement, the emission of green house gases can be decreased to a greater extent.

15.  From the Indian Concrete Journal (ICJ), Journal of Cement and Concrete Research, Journal of Advanced Cement based Materials, American Concrete Institute (ACI) publications literature review has been obtained.  It gives the brief idea about the effect of different types of ashes on concrete when it is replaced in the place of sand or cement. Cont…

16.  Different researcher gives their opinion about the replacement of RHA. ◦ Aramraks et al., (2006) did some experimental study to find out the feasibility of using ash as fine aggregate in structural grade concrete through the investigation of the physical and mechanical properties of concrete in fresh and hardened state. ◦ Aggarwal et al., (2007) studied the effect of use of ash for various percentages (0-50%) replacement of fine aggregates with ash can easily equated to the strength development of normal concrete at various ages. Cont…

17. ◦ Kasemchaisiri et al., (2008) presented the test results of fresh concrete, the use of ash resulted in the reduction of compressive strength due to increase of porosity of hardened concrete. ◦ Rocha et al., (2009) investigates the influence of ash as a replacement for FA, the result shows ash are susceptible to water loss by bleeding and the higher the percentage of ash used as a natural sand replacement the lower the deformation through plastic shrinkage. Cont…

18. ◦ Lee et al., (2010) evaluated the utilization of ash as FA and CA in high-strength concrete. It was found that the slump flow of fresh concrete was slightly decreased from 530mm to 420mm when coarse ash was replaced 100% of normal CA, while fine ash did not affect the slump flow. ◦ Chua Wei Leong et al., (2010) studied the use of municipal solid waste (MSW) incineration ash as aggregate for the production of light weight concrete, the compressive strength s of concrete in the three out of the four test series were able to achieve the ASTM standard requirement on light weight concrete. Cont…

19. ◦ Sun et al., (2008) applied low-profile piezoceramic transducers and it shows the differences in amplitude between wave packets are sensitive to the cracking process of concrete with externally applied loads.  Literature review is important to have the knowledge of amount of replacement and its requirement.  It gives some co-relationship between different form of replacement that has been observed during experiments of different researchers.

20. Physical State Appearance Particle Size Color Odour Specific Gravity Solid – Non Hazardous Very fine powder 25 microns Grey Odourless 1.22 Rice husk ash is pozzolanic material and highly reactive. RHA is high in silica content in the form of noncrystalline or amorphous material silica. It is also durable in nature, several researchers have studied the durability variation of the concrete with pozzolanic materials. Rice Husk Ash: 4.1 TABLE Cont…

21.  After replacement of Fine aggregate with RHA we have the following proportions for M20 grade concrete with different percentages of Fine Aggregate replacement with RHA are as follows:- % Cement Fine aggregate Coarse Aggregate RHA 20% 1 1.08 2.66 0.13 40% 1 0.81 2.66 0.26 60% 1 0.54 2.66 0.39 4.2. TABLE

22.  Compressive Strength Test on: ◦ Cube (150mm x150mm x 150mm) ◦ Cylinders (150mmØ x 300mm)  Split Tensile Strength Test on: ◦ Cylinders (100mmØ x 200mm)  Flexural Strength Test on: ◦ Beam (100mm x 100mm x 500mm)  Rapid Chloride permeability Test  Young’s Modulus Test  Non-Destructive Test Cont…

23.  The strength of the concrete depends on the properties and proportions of the constituent materials, rate of loading, the method of testing and the specimen geometry.  The cube specimen generally exhibit 20 to 25 percent higher strength than cylindrical specimen due to specimen geometry. Cont…

24.  The split tensile strength test is the indirect measurement of the tensile strength by placing a cylindrical specimen horizontally between the loading surfaces.  This method is consists of applying a diametric compressive force along the length of a cylindrical specimen. Cont…

25.  Flexure strength test is the ability check of a beam or slab to resist failure in bending.  Generally flexure strength value is about 2 to 20 percent of compressive strength.  The flexure strength of the specimen is expressed as the modulus of rupture fb. Cont…

26.  Rapid chloride permeability Test has been conducted to find out the permeability of different concretes.  Rapid chloride test was designed to determine the resistance of concrete to the penetration of chloride ions, an indicator of its permeability. Charge passed (coulombs) Chloride ion penetrability >4000 High <100 Negligible Cont…

27.  The elastic modulus of concrete is a very important mechanical parameter reflecting the ability of the concrete to deform elastically.  The modulus of elasticity or Young’s modulus is defined as the slope of the stress-strain curve within the proportional limit of a material.  The secant modulus is defined as the slope of straight line drawn from the origin of axes to the stress-strain curve Cont…

28.  For Non-Destructive Test, piezoelectric transducers and Ultrasonic Pulse Velocity Method have been used to find out the crack depth for conventional concrete and rice husk ash concrete.  The basic principle of crack detection is that, if the crack is at appreciable width and considerable depth, perpendicular to the test path, no signal will be received at the receiving transducer.

29. COMPRESSIVE STRENGTH OF CONCRETE CUBE WITHOUT RHA FIG.1 Compressive strength of M20 grade concrete cube (N/mm2) 13.6 14.82 23.2 25.45 14.22 14.68 21.5 25.3113.72 15.5 22.5 27.83 0 10 20 30 40 50 60 70 80 90 1day 3days 7days 28days Series1 Series2 Series3 Cont…

30. COMPRESSIVE STRENGTH OF CUBE WITHOUT RHA FIG.2 Compressive strength of M25 grade concrete cube (N/mm2) 14.95 15.83 26.23 29.56 15.26 15.66 25.46 32.45 17.72 18.21 24.33 28.23 0 20 40 60 80 100 1day 3days 7days 28days Series1 Series2 Series3 Cont…

31. FIG. 3 Compressive strength of concrete cube without RHA(N/mm2) FIG. 4 Compressive strength of concrete cube with RHA(N/mm2) 13.85 15 22.42 26.2 15.98 16.57 25.34 30.08 1 day 3 days 7 days 28 days M20 M25 8.03 12.6 15.72 20.81 9.17 13.2 17.16 22.44 10.49 14.7 18.12 22.8 1 day 3 days 7 days 28 days M20 with 60% RHA M20 with 40% RHA M20 with 20% RHA Cont…

32. FIG. 5 Compressive strength of M20 grade concrete cube with RHA(N/mm2) 8.03 12.6 15.72 20.819.17 13.2 17.16 22.44 10.49 14.7 18.12 22.8 13.85 15 22.42 26.2 1 day 3 days 7 days 28 days Comparison between M20 grade without RHA and with 20% , 40% & 60% RHA M20 with 60% RHA M20 with 40% RHA M20 with 20% RHA M20 Cont…

33. 23.22 18.03 15.78 14.07 11.9 31.83 24.15 19.4 13.83 10.72 28.34 20.17 16.76 14.76 13.47 0 5 10 15 20 25 30 35 M25 M20 20% RHA 40% RHA 60% RHA Without RHA M20 With RHA Specimen 1 Specimen 2 Specimen 3 FIG. 6 Total Compressive Strength of cylinder in N/mm2 Cont…

34. FIG. 7 Total representation of Split tensile Strength of cylinder in N/mm2 M25 M20 20% RHA 40% RHA 60% RHA Without RHA M20 With RHA 2.74 1.92 1.67 1.43 1.18 2.32 2.09 1.73 1.57 1.24 2.41 2.13 1.79 1.39 1.16 2.49 2.05 1.73 1.46 1.19 Specimen 1 Specimen 2 Specimen 3 Average Cont…

35. FIG. 8 Flexural strength of beam (100mm x100mm x500mm) Strength a Strength a Strength a M20 M25 M20 (20% replacement) Without RHA With RHA Average 12.27 19.8 13.87 23.5 9.47 20.53 Specimen 3 12.6 20.7 13.4 23.5 12.6 20.8 Specimen 2 10.5 20.4 12.9 24.4 7.2 21.3 Specimen 1 13.7 18.3 15.3 22.6 8.6 19.5 0 5 10 15 20 25 30

36.  The concrete specimen so prepared gives the highest compressive strength at 7days compared to 1day and 3days.  The compressive strength of concrete varies with the type of curing and the amount of curing done before the test. Experimentally it is found that 28 days strength is found to be more than 7 days.  RHA replacement, M20 with 20% replacement shows higher strength values than M20 with 40% replacement. Cont…

37.  M20 with 40% replacement shows higher strength values than M20 with 60% replacement. But three of these values are found lesser strength than the specimens tested without rice husk ash replacement.  Use of RHA showing a drastic increase in the amount of water required during the preparation of specimens.  Standard mixes of concrete uses less amount of water as compared to the mixes replaced with rice husk ash. Cont…

38.  We can conclude that in cases of lack of fine aggregate we can use rice husk ash in place of fine aggregate up to a certain extent.  It increases the porosity of concrete specimen and hence decrease the strength of concrete, but lesser amount of replacement will show very negligible change in the strength, so in case of having shortage of fine aggregate we can use some amount rice husk ash.

39.  In future, the availability of rice husk ash as a replacement for fine aggregate can be used if the properties of rice husk ash concrete are similar to standard concrete.  Rice Husk Ash decreases the workability of concrete as the water requirement increases. But if we use RHA, Fly ash with some steel fiber, it will increase the strength of concrete. Hence, can be used as a normal concrete in future.

40.  [1] Assumed standard deviations for target mean strength of concrete taken from table 11, 22 page no. 491-492 of CONCRETE TECHNOLOGY by M.S. Shetty.  [2] Mix proportions according to IS: 456-2000  [3] Mix design as per IS: 10262-2009  [4] Aggregates in Concrete. Asian Journal Of Civil Engineering (Building And Housing) Vol. 8, No. 1 (2007) Pages 49-62. Cont…

41.  [5] Qasrawi H.Y., Marie I.A., The use of USPV to anticipate failure in concrete under compression. Cement and Concrete Research 33 (2003) 2017–2021.  [6] Kasemchaisiri R., Tangtermsirikul S., Properties of Self-Compacting Concrete in Corporating Ash as a Partial Replacement of Fine Aggregate. ScienceAsia 34 (2008): 087-095.  [7] Kim H.K.,Use of power plant ash as fine and coarse aggregates in high-strength concrete.  www.constructor.org

42. Thank you...

Add a comment