STUDY ON FLY ASH MIXED LATERITE SOIL CEMENT BLOCK

Transcription

1 STUDY ON FLY ASH MIXED LATERITE SOIL CEMENT BLOCK Ch. DEVI Assistant Professor, Civil Engineering Department ABSTRACT This study is undertaken in order to come up with an alternative to the conventional clay-burnt bricks. The results of experiments conducted for various percentages of laterite soil and fly ash mixed with 5% and 10% of cement are discussed. The main objective of this study is to obtain a best percentage of fly ash that can be added with soil and cement as stabilizing agent to manufacture bricks and blocks at a low cost which can fulfill the requirement of economically deprived people in the rural and urban parts of the world and on the other hand being environment friendly by utilizing fly ash. The materials incorporated were laterite soil, fly ash, cement and a mould of size cm. For the compressive strength test results it was observed that compressive strength of fly ash mixed lateritecement block is 9.5 N/mm 2 which is similar to that of first class brick. Thus due to higher compressive strength, the fly ash mixed laterite-cement block can also be used as a load bearing wall. Key words: Fly ash, Laterite soil, Cement, Compressive strength, Cost analysis INTRODUCTION: Brick is a common building material which is used for various construction purposes such as to make walls, pavements and other elements in masonry construction. Use of brick for the construction purpose has been practiced for many years and the techniques have been upgraded and modified along the civilization. HISTORY As per the historic evidence found, bricks are one of the oldest known building materials dating back to 7000BC where they were first found in southern Turkey and around Jericho. The first bricks were sun dried mud bricks. Fired bricks were found to be more resistant to harsher weather conditions, which made them a much more reliable brick for use in permanent buildings, where mud bricks would not have been sufficient. The Ancient Egyptians also used sun dried mud bricks as building materials, evidence of which can still be seen today at ruins such as Harappa Buhen and Mohenjo-Daro. Paintings on the tomb walls of Thebes portray slaves mixing, tempering and carrying clay for the sun dried bricks. These bricks also consisted of a 4:2:1 size ratio which enabled them to be laid more easily. However, the brick from laterite soil absorbed excessive water causing cracks and deterioration due to continuous wetting and drying of brick. Also, the laterite brick showed low resistance to abrasion and impact along with intense impact of rodents and insects. Low tensile strength of the laterite brick made the earth structure susceptible to destruction during earthquake. 69

2 OBJECTIVE OF THE STUDY: The objective of perform the present study are listed below: To perform the laboratory test on laterite soil and fly ash and to determine whether it is suitable for brick manufacturing or not. To manufacture the brick in order to determine the quantity of material required for the brick manufacture which gives highest strength value. To forecast the utilization of the fly ash for the large scale and to determine whether the process will contribute to make green environment or not. To compare the properties of the refractory clay brick and Fly Ash Laterite- Cement Block. MATERTIAL CHARACTERISATION: CEMENT: Cement which we have used for our project was Ordinary Portland Cement (OPC) of 53 Grade. 53 grade cement indicates that the particular cement gives compressive strength of 53 N/mm 2 at the age of 28 days. PROPERTIES OF 53 GRADE CEMENT S.No PHYSICAL PROPERTIES RESULTS 1 Specific gravity of cement Normal consistency 32% 3 Initial setting time (minutes) 4 4 Final setting time(minutes) 600 FLY ASH : Fly ash particles are generally spherical in shape and the size of the particle ranges from 0.5 µm to 300 µm. The main chemical components which are present in fly ash are SiO 2, Al 2O 3, Fe 2O 3 and CaO. Fly ash was made available by Manohar Enterprises, Rajahmundry. LATERITE SOIL: Laterite is a type of soil which is formed due to the intense, prolonged weathering of the parent rock in tropical climates. Extensive study on availability of laterite soil in India was done. On the basis of survey, the laterite deposit near Ramesampeta, A.P. was found to be the most suitable location to acquire the laterite soil for this project. Laterite soil was acquired from Ramsampeta of A.P. 70

3 S.No PROPERTIES OF LATERITE SOIL PHYSICAL RESULTS PROPERTIES 1 Moisture Content specific gravity (Cu) = 10.63& (Cc) = 1.03, According to Indian Soil Classification Code, IS: classified as Well Graded (GW). 4 Liquid limit 34.90% 5 plastic limit 18.74% 6 Standard Proctor Test Bulk Density kg/m3 Dry Density kg/m3 Optimum Moisture Content 15.5% 7. Modified Proctor Test Bulk Density 1.90 kg/m3 Dry Density 1.84 kg/m3 Optimum Moisture Content 16.8% MATERIALS PROPORTIONING: The proportioning of the quantity of material is a trial method where the soil block is prepared by adding various percentages of fly ash and cement. Proportion is carried out in order to determine the most economical and practical combination of the materials which are to be mixed to form a single product which will satisfy the performance required under particular condition of use. In order to perform this project, the material was categorized into 2 primary groups which are listed below: 1. Addition of 5% of cement by the weight of soil. Additions of 10% fly ash by the weight of soil. Additions of 20% fly ash by the weight of soil. Additions of 30% fly ash by the weight of soil. Addition of 40% fly ash by the weight of soil. 2. Addition of 10% of cement by the weight of soil. Additions of 10% fly ash by the weight of soil. Additions of 20% fly ash by the weight of soil. Additions of 30% fly ash by the weight of soil Addition of 40% fly ash by the weight of soil 71

4 ANALYSIS AND DISCUSSION OF RESULT: On completion of curing of block for 28 days, its compressive strength was tested on Compression Testing Machine. All the cast blocks were tested for the parameters like compressive strength and water absorption as per the requirements of IS: common clay burnt brick &IS for soil-cement blocks and The compressive strength and water absorption tests were carried out as per the specifications given in IS , Part - I and Part - II respectively. Each block was weighed before testing to calculate its density LATERITE BLOCK. DENSITY OF BLOCKS: Density of any substance is defined as the mass per unit volume of the particular substance. It is denoted by Kg/m 3 or gm/cm 3. DENSITY OF BLOCK FOR ADDITION OF 5% CEMENT BY WEIGHT OF SOIL AND VARYING PERCENTAGE OF FLY ASH % FLY ASH SAMPLE -1 (gm/cm 3 ) SAMPLE -2 (gm/cm 3 ) SAMPLE -3 (gm/cm 3 ) AVERAGE (gm/cm 3 ) DENSITY OF BLOCK FOR 10% CEMENT BY WEIGHT OF SOIL AND VARYING PERCENTAGE OF FLY ASH % FLY ASH SAMPLE 1 (gm/cm 3 ) SAMPLE 2 (gm/cm 3 ) SAMPLE 3 (gm/cm 3 ) AVERAGE (gm/cm 3 )

5 COMPRESSIVE STRENGTH TEST RESULT For each of the mixes, the blocks were subjected to compression test and the average compressive strength of blocks was determined. The test result obtained is shown below: %CEME NT BY WEIGHT OF SOIL ADDITION OF 5% CEMENT BY THE WEIGHT OF SOIL % FLY ASH BY WEIGHT OF SOIL SAMPLE 1 (N/mm 2 ) SAMPLE 2 (N/mm 2 ) SAMPLE 3 (N/mm 2 ) AVERAGE COMPRES SIVE STRENGT H (N/mm 2 ) COMPEESSIVE STRENGTH IN N/mm ADDITION OF 5% CEMENT BY WEIGHT OF SOIL SAMPLE 1 SAMPLE 2 SAMPLE 3 AVERAGE 0 10% 20% 30% 40% % of FLY ASH ADDITION OF 10% CEMENT BY THE WEIGHT OF SOIL: %CEMENT BY % FLY ASH BY SAMPLE 1 SAMPLE 2 SAMPLE 3 WEIGHT OF SOIL WEIGHT OF SOIL (N/mm 2 ) (N/mm 2 ) (N/mm 2 ) AVERAGE COMPRESSIVE STRENGTH (N/mm 2 )

6 COMPEESSIVE STRENGTH IN INTERNATIONAL JOURNAL OF MULTIDISCIPLINARY ADVANCED RESEARCH TRENDS 12 ADDITION OF 10% CEMENT BY WEIGHT OF SOIL 10 N/mm % 20% 30% 40% % of FLY ASH SAMPLE 1 SAMPLE 2 SAMPLE 3 AVERAGE COST ANALYSIS AND COMPARISION Cost Analysis of the block was done for the block showing optimum property. In India, cost of brick per piece is minimum 5 rupee. For block of size 150 mm x 150 mm x 150 mm, following quantity of materials per block was required: Particulars Quantity (Kg) Cost/Kg Cost/Material Laterite Soil Fly Ash Cement TOTAL COST = INR 3.35 PER BLOCK For brick of size 190 mm x 90 mm x 90 mm, following quantity of materials per block was required: Particulars Quantity (Kg) Cost/Kg Cost/Material Laterite Soil Fly Ash Cement TOTAL COST= INR 1.526PER BRICK CONCLUSION 3.1. General From the experiments performed, it was found that the fly ash mixed lateritecement block is suitable for use as a building material as it possess the properties similar to that of clay burnt brick. Following the results obtained and discussion in previous chapters, following points can be concluded. 74

7 1. The optimum strength is obtained by addition of 10% cement and 20 % fly ash by the weight of soil. 2. The optimum strength shown by the bricks is similar to that of Class A burnt clay bricks. 3. The cost of block when made to the size of brick is reduced by 59% per brick which makes it easily affordable by the poor people. 4. Water absorption shown by the brick with optimum property is below 15% which is as specified by IS: Hence, the durability of brick is suitable. 5. The brick kilns emit toxic fumes containing suspended particulate matters rich in carbon particles and high concentration of carbon monoxides and oxides of sulphur (SOx) that are harmful to eye, lungs and throat whereas brick from laterite can be prepared without utilisation of fire for obtaining its strength. This reduces the emission of harmful gases to the environmentthereby making the procedure eco-friendly. 6. Over 300 million tons of fly ash per year is being generated which causes various problems related to health as well as disposal of waste. However, by practically implementing this procedure of brick production, the fly as consumption can be increased thereby stabilising the production and usage of fly ash. 7. Due to its adequate strength, it can be used in various purposes like load bearing walls, pavements etc. 8. More than 350 million tons of fertile soil per year is used in production of clay which has caused adverse impact on agriculture production rate. This can lead to the downfall on economic growth of country. On other hand, use of infertile laterite soil for the production of bricks has no adverse effect on agricultural activities. FUTURE SCOPE OF WORK In regard to the project STUDY OF FLY ASH MIXED LATERITE- CEMENT BLOCK, following things can be taken in consideration for the future: 1. This test has been performed only using laterite soil, cement and fly ash. However, it can be performed using admixtures to improve the binding properties and overall strength of the material. 2. This process was performed manually. Compaction of mix was done using hammer of modified proctor test. However, the process can be done using mechanically operated machines which may enhance the properties of the blocks due to efficient compaction. 3. The block was stabilised using 53 Grade OPC. It can also be tested by using other stabilising agents like lime and bitumen. 75

8 CODES IS: CLASSIFICATION AND IDENTIFICATION OF SOILS FOR GENERAL ENGINEERING PURPOSES IS: COMMON BURNT CLAY BUILDING BRICKS- SPECIFICATION IS: 3495 (PartII)-1976 WATER ABSORPTION TEST FOR CLAY BURNT BRICKS IS: SPECIFICATION FOR SOIL BASED BLOCKS USED IN GENERAL BUILDING CONSTRUCTION IS 12269:1987 SPECIFICATION FOR 53 GRADE ORDINARY PORTLAND CEMENT. REFERENCES: 1. SOIL MECHANICS AND FOUNDATION ENGINEERING (GEOTECHNICAL ENGINEERING) Dr. K.R. Arora 2. FEASIBILITY STUDY ON UTILISATION OF LATERITE SOIL FOR STABILIZED EARTH BLOCKS Dr. R. Kumutha, Dr. K. Bijai, S.Prakash, K.Rajeshkumar, S.Sakthi & Shembiang Marthong Research Desk, 2013, Jul- Sep 2(3) USE OF LATERITE AS A SUSTAINABLE BUILDING MATERIAL IN DEVELOPING COUNTRIES, an article in INTERNATIONAL JOURNAL OF EARTH SCIENCES AND ENGINEERING, MAY 2015 BY Krishna R. Reddy & Venkat Reddy. 4. EXPERIMENTAL INVESTIGATION ON CEMENT STABILIZED SOIL BLOCKS A R Veena1, P Siva Kumar and Eapen Sakaria 5. STABILIZATION OF SOIL BY DIFFERENT PROPORTIONS OF FLY ASH PARTIAL REPLACEMENT, an article in Journal of Academia and Industrial Research(JAIR) Volume 2, Issue 9 February 2014 by Stephen George Emmanuel and Y.K. Bind 6. INDIAN FLY-ASH PRODUCTION AND CONSUMPRION SCENARIO, an article in International Journal of Waste Resources (IJWR) by Md. Emamul Haque. 76