International Journal of Engineering Science Invention Research & Development; Vol. II Issue III September e-issn:

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1 CHARACTERISITICS STUDY OF BENTONITE MORTAR WITH REPLACEMENT OF CEMENT R.Selvaraj ** and R.Priyanka * **Principal scientist, CSIR-CECRI, Karaikudi * P.G. project Student, CSIR-CECRI, Karaikudi selvarajcecri@gmail.com Abstract- Manufacturing of cement is energy intensive process besides polluting the atmosphere; release of greenhouse gases like Carbon dioxide threatens global warming also. It depletes the natural resources of earth. This has led to the concept of using mineral admixtures in concrete. Though there are many mineral admixtures are available such as fly ash, micro silica, silica fume etc., a still cheaper material that is Bentonite is considered in this paper to mix with cement mortar to study its effectiveness as a mineral admixture in cement mortar with Ordinary Portland cement (OPC) and Portland pozzalano cement (PPC). The ratio of replacement of cement is varied with an increment of 2.5% up to 20%.It is found from the compressive strength test, replacement with OPC is up to 15% and in PPC it is up to 12.5% is optimum. The test results are elaborately discussed in this paper. I INTRODUCTION The first mortars were made of mud and clay. After that Babylonian constructions were made of baked mortar, using lime. In the context of increased awareness regarding the ill effect of the over exploitation of natural resources. Eco-friendly technologies are to be developed for effective in construction will be achieved only area of thinking from every corner construction materials. Concrete is a composite material formed by the combination of cement, aggregate and water in a particular in such a way that the concrete produced meets the need of the job on hand as regards it s workability, strength, durability and economy. In a concrete construction cement is an important material. Cement act as a binder material in concrete, to provide good bonding between the fine aggregate with water. Nowadays cost of cement is high compared to the other material (i.e., clay, fly ash, rice husk etc.), so, we the engineers to find the alternative material for cement. A. Clay Clay minerals are typically formed over long periods of time by the gradual chemical weathering of rocks, usually silicate-bearing, by low concentrations of carbonic acid and other diluted solvents. These solvents, usually acidic, migrate through the weathering rock after leaching through upper weathered layers. Clay deposits may be formed in place as residual deposits in soil, but thick deposits usually are formed as the result of a secondary sedimentary deposition process after they have been eroded and transported from their original location of formation. B. Types of Clay a. Residual Clay It comes directly from gradual weathering of rock into very fine particles. The particles became mixed with water and material from the surrounding soil. b. Sedimentary Clay It is formed when particles of weathered rocks are carried from the place in which they were formed, usually by streams of water and deposited in another place. It occurs in layers. C. Classification of Clay a. Kaolinite Clay Kaolinite is a clay mineral, part of the group of industrial minerals, with the chemical composition Al 2 Si 2 O 5 (OH) 4. It is a layered silicate mineral, with one tetrahedral sheet linked through oxygen atoms to one octahedral sheet of alumina octahedral. b. Ball Clay Ball clays are kaolinitic sedimentary clays that commonly consist of 20-80% kaolinite, 10-25% mica, and 6-65% quartz. Localized seams in the same deposit have variations in composition, including the quantity of the major minerals, accessory minerals and carbonaceous materials such as lignite. [1] They are fine-grained and plastic in nature. c. Fire Clay R.Selvaraj and R.Priyanka ijesird, Vol. II (III) September 2015/ 178

2 Fire clay is a term applied to a range of refractory clays used in the manufacture of ceramics, especially fire brick. The United States Environmental Protection Agency defines fire clay very generally as a "Mineral Aggregate composed of hydrous silicates of aluminium (Al 2 O 3.2SiO 2.2H 2 O) with or without free silica. d. Bentonite Clay Bentonite is an absorbent aluminium phyllosilicate, essentially impure clay consisting mostly of montmorillonite. There are different types of bentonite, each named after the respective dominant element, such as potassium (K), sodium (Na), calcium (Ca), and aluminium (Al). Experts debate a number of nomenclatorial problems with the classification of bentonite clays. D. Advantages of Clay Natural clay, of which terracotta is made of, is the most flexible form of earth. It is essentially plastic and passive, i.e. the least resisting material. Unlike any other material clay can be molded in to any shape or size without least effort. Clay demands no tool for its being worked; it is fashioned directly by hands. But it retains it nature in the process, its colour and texture. Clay can also be fashioned using machines; and tiles and pottery for large-scale business are manufactured using machines. Clay is a low temperature, red-burning porous material of earth. It is the eco- friendly building material available on earth. The common red clay used for the production of tiles is the most abundantly available mineral, with high plasticity and workability in wet condition. Clay is a healthy solution for modern day building construction. II SCOPE OF THE STUDY Environmental pollution is the major issue due to emission of different environmental pollutants, during the process of manufacturing of cement thus affecting its quality. The cost of the material is also increasing day by day when compared to other materials. So it has become our necessity to find an alternate material for cement. III OBJECTIVE OF THE STUDY The main objective is to study about the effect of Bentonite powder as a partial replacement for cement in mortar. The following experimental tests are planned to carry out in Phase II:- Treatment of Bentonite Strength Tests Characterization Tests Corrosion Resistant Tests IV SELECTION OF MATERIALS A. Bentonite Clay Bentonite is an absorbent Aluminium Phyllosilicate, essentially impure clay consisting mostly of montmorillonite. There are different types of bentonite, each named after the respective dominant element, such as potassium (K), sodium (Na), calcium (Ca), and aluminium (Al). Experts debate a number of nomenclatorial problems with the classification of bentonite clays. Sodium Bentonite Sodium bentonite expands when wet, absorbing as much as several times its dry mass in water. Because of its excellent colloidal properties, it is often used in drilling mud for oil and gas wells and boreholes for geotechnical and environmental investigations. The property of swelling also makes sodium bentonite useful as a sealant, since it provides a self-sealing, low permeability barrier.before its usage we are going to treat it rawly, thermally and chemicaly.after that cement is going to replace by bentonite clay (sodium) with (2.5%, 5%, 7.5%, 10%, 12%, 15%, 17.5% and 20%), then for each sample mix proportion cubes are casted and undergone certain tests to investigate the strength of the concrete with respect to replacement. R.Selvaraj and R.Priyanka ijesird, Vol. II (III) September 2015/ 179

3 Figure 1. Sodium Bentonite Clay Fine aggregate shall conform to the requirements of IS The fraction from 4.75mm-150 microns are termed as fine aggregate B. Fine Aggregate Table 1: Physical Properties of fine aggregate Sl.No Tests conducted Relevant Code Value obtained 1 Specific gravity IS 2386 (Part-I) Bulk density IS 383 : kg/m 3 3 Water absorption IS 383 : % 4 Fineness modulus IS 383 : C. Cement The main binders used in this experimental study are Ordinary Portland Cement and Portland Pozzolana Cement. D. Ordinary Portland cement Table 2: Physical Properties of OPC Ordinary Portland Cement & Portland Pozzalano Cement is used in this work. The physical properties are tested as per IS 12269:1987. The physical properties of cement are given in Table 2 & Table 3. Sl.NO Type of Test conducted Relevant code Results 1 Standard consistency test IS 8112: % 2 Fineness test IS 8112:2013 1% 3 Specific gravity IS 8112: Initial setting time IS 8112: Min 5 Final setting time IS 8112: min Table 3: Physical Properties of PPC Sl.NO Type of Test conducted Relevant code Results 1 Standard consistency test IS 1489: % 2 Fineness test IS 1489:1991 6% 3 Specific gravity IS 1489: R.Selvaraj and R.Priyanka ijesird, Vol. II (III) September 2015/ 180

4 4 Initial setting time IS 1489: min 5 Final setting time IS 1489: min E. Water According to IS 3025 (Part 21)-2009, water to be used for mixing and curing should be free from injurious or deterious materials. Potable water is generally considered satisfactory. In the present investigation, available water within the campus is used for both mixing and curing purposes.. V. MIX PROPORTION The cement to fine aggregate ratio was 1:3 and the water /cement ratio was taken as 0.4. Conventional and replacement mortar cubes were prepared. Figure 3. Compression Testing of cube Figure 4. After Compression Testing Figure 2. Mixing of Bentonite VI COMPRESSIVE STRENGTH The Compressive strength of the conventional and replacement concrete specimen was determined using 70.6 mm x 70.6 mm x 70.6 mm mould. The testing is conducted in Compression Testing Machine (Load capacity of 2000 KN). VII TEST RESULTS Test results for Conventional Mortar cubes of OPC and PPC are shown in Table 4, Table 4: Compressive strength for Conventional mortar cubes No of Days Compressive Strength (N/mm 2 ) OPC PPC R.Selvaraj and R.Priyanka ijesird, Vol. II (III) September 2015/ 181

5 Compressive Strength ( N/mm 2 ) International Journal of Engineering Science Invention Research & Development; Vol. II Issue III September Days 7 Days 28 Days Number of Days OPC-43 PPC Figure 5. Compressive strength for Conventional OPC & PPC mortar cubes. From the Compressive strength test results for conventional OPC & PPC at 3,7, & 28 days it was observed that, the OPC attains higher strength than PPC. A. Compressive Strength of mortar cubes using Bentonite replacement with OPC The graph is plotted for the compressive strength of Bentonite replacement mortar cubes with OPC Vs Number of days as shown in the figure 6., Table 5: Compressive Strength of mortar cubes using Bentonite replacement with OPC Compressive strength (N/mm 2 ) Days / Ratio Nominal mix 2.5% B 5.0% B 7.50 % B 10 % B 12.5 % B 15.0 %B 17.5 % B 20.0%B 3 Days Days Days From the Compressive strength test results of mortar cubes with Bentonite replacement of 2.5,5,7.5,10,12.5,15,17.5 & 20% it was found that an optimum Compressive strength was obtained at 12.5% which is slightly higher than the Nominal mix strength. Figure 6. compressive Strength of mortar cubes using Bentonite replacement with OPC B. Compressive strength for mortar cubes using Bentonite replacement with PPC Grade The graph is plotted for the compressive strength of Bentonite replacement mortar cubes with PPC Vs Number of days as shown in the figure 10. R.Selvaraj and R.Priyanka ijesird, Vol. II (III) September 2015/ 182

6 Figure 8. Compression Testing Machine Figure 7. Specimen after testing Figure 9.Crack pattern of specimen R.Selvaraj and R.Priyanka ijesird, Vol. II (III) September 2015/ 183

7 Compressive Strength ( International Journal of Engineering Science Invention Research & Development; Vol. II Issue III September 2015 Table 6: Compressive strength for mortar cubes using bentonite replacement with PPC Compressive strength (N/mm 2 ) Days /Ratio Nominal mix 2.5%B 5.0%B 7.5 % B 10.0%B 12.5 % B 15.0%B 17.5 % B 20 % B 3 Days Days Days % 2.50% 5% 7.50% 10% 12.50% 15% 17.50% 20% 3 Days 7 Days 28 Days Number of Days Figure 10. Compressive strength for mortar cubes using Bentonite replacement with PPC Grade IX CONCLUSION From the available number of literatures on the properties and characteristics of Bentonite clay with replacement of cement, it is noted that the Bentonite can be used in a place where late stage strength is required and for durability purposes it gives good result at every stage. Hence, the present study aims to conduct various experimental tests on Bentonite clay with replacement of cement mortar using different binders and to arrive at an optimum percolation rate and strength. In the project compressive strength of OPC & PPC with Raw Bentonite replacement were made. It was found that significant compressive strength was achieved at 15.0 % replacement of Bentonite for OPC & 12.5% for PPC. Thus, Bentonite clay can be recommended as a good replacement material in concrete. Reference [1] Pengzhang,Qiaoyan Guan and Qingfu Li Mechanical properties of plastic concrete containing Bentonite, Cement and Concrete Research 33, ,2003. [2] V.A.Grishin and L. M. Deryugin, Experience In The Use Of Bentonite-Cement Concrete ForRepairing The Core Of The Earthfill Dam Of Kureiskaya Hpp Power Technology and Engineering Vol. 40,No. 2, [3] M. Katsioti, N. Katsiotis, G. Rouni, D. Bakiritzis, M. Loizidou, The effect of Bentonite/Cement mortar for the stabilization/solidification of sewage sludge containing heavy metals, Cement and Concrete composites 30, ,2008. [4] Rau L Ferna Ndez1, Jaime Cuevas2 And Urs K. Ma Der, Modelling concrete interaction with a bentonite barrier Eur. J. Mineral.2009, 21, , Published online November [5] James O.O.,M.Adediran Mesubi, F. A. Adekola, E. O. Odebunmi, and J. I. D. Adekaye, Benefication And Characterisation Of A Bentonite From North-Eastern Nigeria, Journal of north Carolina Academy of Science, 124(4),pp ,2008. [6] Kaci, M.Chaouche,P-A. Andreani, Influence of Bentonite clay on the rheological behaviour of fresh mortars cement and concrete research,vol 41,Issue4,April,pages ,2011. R.Selvaraj and R.Priyanka ijesird, Vol. II (III) September 2015/ 184

8 [7] Shazim Ali Memom, RaoArsalan, Sardar Khan, Tommy Yiu Lo, Utilization of bentonite as a partial replacement of cement in concrete, Construction and Building materials, Vol 39, Pages , May [8] Arthur G. Clelyi Ann Robert W. Doehler, Industrial Applications Of Bentonite.International Journal Of Concrete Structures and Materials. American Colloid Company, Skokie, Illinois, ISSN , Vol. 03, No. 02, January. [9] Justin K.Norvell,Jane G.Stewart,Maria C.G.Junenger, Effects of Clay and Clay sized Particles on Concrete. International Journal of Concrete Structures and Materials.Vol 6, No.4, pp , December [10] Junaid Akbar, Bashir Alam, Muhammad Ashraf, Salman Afzal,Asfandyar Ahmad, Khan Shahzada, Evaluating the Effect of Bentonite on Strength and Durability of High Performance Concrete,International Journal of Advanced Structures and Geotechnical Engineering,ISSN , Vol. 02, No. 01, January R.Selvaraj and R.Priyanka ijesird, Vol. II (III) September 2015/ 185