STUDY OF STRENGTH AND DURABILITY ON HIGH STRENGTH CONCRETE BY PARTIALLY REPLACING CEMENT WITH GGBS AND FLY ASH OVER ACID ATTACKS

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 4, April 2017, pp Article ID: IJCIET_08_04_051 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed STUDY OF STRENGTH AND DURABILITY ON HIGH STRENGTH CONCRETE BY PARTIALLY REPLACING CEMENT WITH GGBS AND FLY ASH OVER ACID ATTACKS D. Mani Deep P.G Student, Civil Engineering Department, SRM University, Kattankulathur , Chennai, Tamil Nadu, India N. A. Jabez Assistant Professor, Civil Engineering Department, SRM University, Kattankulathur , Chennai, Tamil Nadu, India ABSTRACT Concrete is most extensively used material in construction. CO2 is emitted during the manufacture of cement, damaging the environment. By lowering cement usage leads to reduction of CO2 generated. The increasing demand for cement made researchers to think about the supplementary materials for partial replacement of cement. In the same case if these supplementary materials are naturally occurring or any industrial wastes, then it results in both environment sustainability and economical. These materials are called as pozzalonas, which exhibit cementetious properties when combined with calcium hydroxide. Many research works state that materials like fly ash, GGBS, silica fume, metakaolin can be used as partial replacement for cement. The present work focuses on investigating characteristics of M60 grade concrete with partial replacement of cement with GGBS and fly ash. GGBS replacing cement via 10%, 15%, 20% and fly ash replacing cement as 5% constant. The cubes, cylinders and prisms are tested for compressive strength, split tensile strength, flexural strength. Durability studies with sulphuric acid and hydro chloric acid were also conducted. Key words: GGBS, Fly Ash, Durability, Compressive Strength, Tensile Strength, Flexural Strength, RCPT Test. Cite this Article: D. Mani Deep and N. A. Jabez, Study of Strength and Durability on High Strength Concrete by Partially Replacing Cement with GGBS and Fly Ash Over Acid Attacks. International Journal of Civil Engineering and Technology, 8(4), 2017, pp

2 Study of Strength and Durability on High Strength Concrete by Partially Replacing Cement with GGBS and Fly Ash Over Acid Attacks 1. INTRODUCTION In the last millennium concrete has demanding necessities both in terms of technical attainment and economy. Concrete can be mould into any shape imparting required strength properties. The main constituents in concrete are cement, sand, crushed stone and water, on which the properties of concrete depend. In addition to this workmanship, quality control also plays a vital role on properties of concrete. The main drawback is emission of CO2 which is very harmful to the environment while producing cement. By using supplementary materials as replacement for cement results in reducing usage of cement as well as reducing emission of CO2.In this experimental work, GGBS and fly ash are used partially in place of cement with different proportions and exposed to acidic conditions by curing in sulphuric acid and hydrochloric acid to study the various parameters. Various numerous works have been done by researchers about GGBS and fly ash and given some conclusions. S. P. S. Ramya, A. M. N. Kashyap (2014) investigated, Concrete when subjected to severe environments its durability can significantly decline due to degradation. Degradation of concrete structures by corrosion is a serious problem and has major economic implications. Yogendra O. Patil, Dr. Arun Kumar Dwivedi investigates and presents an experimental study of compressive and flexural strength of concrete prepared with Ordinary Portland Cement, partially replaced by ground granulated blast furnace slag in different proportions varying from 0% to 40% and concluded that the 20% replacement of cement is possible without compromising the strength with 90 days curing..vinayak Awasare and Prof. M. V. Nagendra, Analysis of Strength Characteristics of GGBS Concrete, International Journal of Advanced Engineering Technology, Vol. V/Issue II/April-June, By considering those works, this work is carried out to study the durability and strength characteristics of high strength concrete with partial replacement of GGBS and fly ash under acidic environment. 2. OBJECTIVE AND SCOPE To study durability mechanical properties of M60 grade of concrete using partial replacement of cement by GGBS and fly ash (10+5)%, (15+5)%, (20+5)% respectively. To study the durability properties of concrete (Hydro choric acid resistance and sulphuric acid resistance attack). To find the optimum % of replacement of cement by GGBS and FLYASH by imparting better strength and durability properties. Reduce the usage of cement by replacing it with GGBS and fly ash. Utilization of industrial waste material as cement replacement material. Cost of production concrete is to be minimized. 3. MATERIALS USED 3.1. Cement In present work Ordinary Portland cement 53 grade brand conforming to Indian Standard is used. The cement is confirmed by subjecting to various tests as per Indian Standard code. Specific gravity of cement used is Coarse Aggregate The aggregates which passing through 12.5mm and retained on 10mm are used. Aggregates retaining on 4.75mm IS sieve are known as coarse aggregates. Specific gravity of coarse editor@iaeme.com

3 D. Mani Deep and N. A. Jabez aggregates used is 2.74 and density is 1638 kg/m 3. Fineness modulus is 4.1 and water absorption is 0.73% Fine Aggregates The aggregates passing through the 4.75mm IS sieve are called as fine aggregates. For this work fine aggregates used is river sand. For present research work sand is screened and cleaned to remove any unwanted materials and tested as per IS 2386:1968 (Part-3). Specific gravity of sand is 2.6 and density is 1588 kg/m 3. Fineness modulus is 3.01 and grading zone II GGBS Ground granulated blast furnace slag is a waste from iron or slag industries. It has good impact over strength and durability of concrete up to certain extent. Growth in urbanization and industrialization, by products from them becoming a major problem to recycle under waste management. It plays a vital role in durability properties of concrete as well as reducing the cost of production of concrete. It has cementitious properties and its size similar to sand. Specific gravity for GGBS is Physical Properties of Ground Granulated Blast Furnace Slag (GGBS) Physical Form =Off White Powder Bulk Density (vibrate) = Kg/m 4 Specific Surface area = m 2 /Kg Bulk Density (Loose) = Kg/m Flyash In PCC applications most commonly used pozzolonas is fly ash. Pozzolonas are siliceous or siliceous and aluminous material, which in a finely divided particles and in the presence of water, it react with calcium hydroxide to produce cementitious compounds. Particle size of fly ash varies from 1μm to 100μm in diameter with more than 50% under 20μm. Specific gravity of fly ash is 2.7. Table 1 chemical composition of fly ash and GGBS Materials Fly ash GGBS SiO 2 (wt, %) Fe 2O 3 (wt, %) CaO (wt, %) Al 2O 3 (wt, %) MgO (wt, %) SO 3 (wt, %) Na 2O (wt, %) K 20 (wt, %) L.O.I (wt, %) Chemicals Specimens are cured in 5% of H2SO4 solution and 5% of HCL solution for 28 days. For that 98% H2SO4 with density 1.8 to 1.84 g/ml and 36% HCL with density 1.24 g/ml are used editor@iaeme.com

4 Study of Strength and Durability on High Strength Concrete by Partially Replacing Cement with GGBS and Fly Ash Over Acid Attacks For getting better results and workability super plasticizer is added. In this work aura mix 400 (polycarboxlic ether) is used in desired proportion. 4. METHODOLOGY 4.1. Mix Design of Concrete (M60) As per ACI 211.4R-2008 mix design is made. Fly ash and GGBS are added in different proportions (0%+0%, 5%+10%, 5%+15% and 5%+20%). Finalized Mix (M60) Table 2 Mix proportion of concrete (M60) without any admixtures Cement Fine Coarse (Kg/m 3 ) Aggregate(Kg/m 3 ) Aggregate(Kg/m 3 ) M Water + (0.6% S.P) (Lt/m 3 ) 4.2. MIXING AND CASTING Machine mixing is adopted for mixing the ingredients for better results. First materials are weighed exactly and blended with hand for unique proportion. Weighed water has to be added in different intervals till it reaches uniformity. Thoroughly mixed concrete is moulded into cubes, cylinders and prisms. Table 3 Specimens casted for current work ADMIXTURES NO OF SPECIMENS FLYASH (%) GGBS (%) H 2O CURING 5% HCL CURING 5% H 2SO 4 CURING C a S b P c C S P C S P a cubes b cylinders c prisms 4.3. Curing After casting work is over moulded specimens are stored in room temperature for 24 hours. After this period specimens are taken out from moulds carefully without damaging the surfaces. These specimens are exposed to environment after demoulding for some time to remove water content. Then these specimens are placed in different curing solutions for further tests to be conduct. Acidic solutions (5% HCL and 5% H2SO4) are to be checked in regular intervals to maintain the ph value Testing The specimens cured as stated above are tested according to IS 516:1959 code standards and ASTM C1202 code. Compressive strength for cubes, split tensile strength and RCPT for cylinders and flexural strength for prisms are conducted. Weight loss parameters also checked over acidic attacks. The results mentioned were average of the values obtained from three specimens editor@iaeme.com

5 D. Mani Deep and N. A. Jabez 5. RESULTS AND DISCUSSION 5.1. Compressive Strength The size of each specimen is 150m x 150mm x 150mm and cured in H2O, 5% HCL and 5% H2SO4 solutions for each mix proportion. Results are as shown below. Table 3 Compressive strength of cubes (M60) in different solutions for 28 days Mix ID %of Fly ash % of GGBS Compressive Strength M60(N/mm 2 ) H 2O 5% HCL 5% H 2SO 4 M M M M Figure 1 Variation in compressive strength for 28 days 5.2. Split Tensile Strength Cylinders of size 100mm x 200mm are casted and cured in different solutions. After 28 days take them out and leave them in open dried place for removing water. Their results were represented below in tabular form. Table 4 Split tensile strength for specimens (M60) cured in different solutions Split Tensile Strength M60 (Mpa) Mix ID %of Fly ash % of GGBS H 2O 5% HCL 5% H 2SO 4 M M M M editor@iaeme.com

6 Study of Strength and Durability on High Strength Concrete by Partially Replacing Cement with GGBS and Fly Ash Over Acid Attacks Figure 2 Variation in split tensile strength for 28 days 6. FLEXURAL STRENGH The specimens of size 100mm x 100mm x 500mm were prepared for al mixes and flexural tests are carried out according to IS code standards. 3 point loading is carried out and results are tabulated below. Below mentioned values is average of three identical specimens. TABLE 5 Flexural strength for specimens (M60) cured in different solutions Flexural Strength M60 (Mpa) Mix ID %of Fly ash % of GGBS H 2O 5% HCL 5% H 2SO 4 M M M M Figure 3 Variation in flexural strength for 28 days 7. RCPT (RAPID CHLORIDE PERMEABILITY TEST) For this test standard testing procedures are stated in ASTM C The test is carried out for 360minutes. Cylindrical specimens of size 50mm or 100mm in thick and 100mm in diameter are used. From the normal specimens 100mm x 200mm are cut down by core cutter. Voltage of 60v DC is used in this experiment and one lead is immersed in o.3m NaOH solution and other in 3% NaCl solution. For every 30minutes we need to take the reading. The summation of all readings is the cumulative value. Depending upon the charge passing through specimen s chloride permeability is adopted. If the charge passed is above 4000 chloride permeability is high, if it is 2000 to 4000 chloride permeability is moderate, the value lies between 1000 to editor@iaeme.com

7 D. Mani Deep and N. A. Jabez 2000 then chloride permeability is low, similarly 100 to 1000 denotes very low and below 100 negligible. TABLE 6 RCPT results for specimens (M60) cured in different solutions for 28 days Charge passed for 360minutes (coulombs) Mix ID %of Fly ash % of GGBS H 2O 5% HCL 5% H 2SO 4 M M M M Figure 4 Variation of charge passed through different specimens in different curing conditions 8. WEIGHT LOSS PARAMETER Some of the specimens are cured in acidic solutions, due to that surface degradation occurs. It results in weight loss and affecting the strength and durability properties. After casting work the initial weights are calculated and final weights are calculated after curing period. The main part is before weighing the specimens they have to be dried to remove water content. Table 7 Weight loss percentage for specimens (M60) cured in different solutions Mix ID %of Fly ash % of GGBS Weight Loss Percentage (%) H 2O 5% HCL 5% H 2SO 4 M M M M editor@iaeme.com

8 Study of Strength and Durability on High Strength Concrete by Partially Replacing Cement with GGBS and Fly Ash Over Acid Attacks Figure 5 Weight loss percentages for different specimens in different curing conditions 9. CONCLUSIONS The compressive strength of high strength concrete is improved maximum by replacement of cement by fly ash and GGBS (5%+15%) in acidic conditions. The split tensile strength also increased by replacement of cement with fly ash and GGBS (5%+15%) in acidic environment. The flexural strength also increased by replacing cement with fly ash and GGBS at optimum percentages. The durability properties are improved with the replacement of GGBS and fly ash and optimum values obtained by replacing fly ash by 5% and GGBS by 15%. By the replacement of GGBS the attack due to acid is reduced and it results in reduction of weight loss parameters. By the RCPT test, its clearly shown that by addition of GGBS and fly ash the chloride penetration is reduced. The attack of sulphuric acid is more when compared to hydrochloric acid similarly the weight loss is more in sulphuric acid when compared to hydrochloric acid. By replacement of GGBS and fly ash at optimum percentages we can get high strength concrete without altering its strength and with improved durability properties. REFERENCES [1] Vinayak Awasare and Prof. M. V. Nagendra., Analysis of Strength Characteristics of GGBS Concrete, International Journal of Advanced Engineering Technology, Vol. V/Issue II/April-June, [2] Mrs. Veena G. Pathan, et al, Evaluation of concrete properties using ground granulated blast Furnace slag, International Journal of Innovative Research in Science, Engineering and Technology Vol. 1, Issue 1, (2012), pp [3] Venu Malagavelli et. al. High performance concrete with GGBS and robo sand International Journal of Engineering Science and Technology Vol. 2(10), 2010, [4] Reshma Rughooputh and Jaylina Rana, Partial Replacement of Cement by Ground Granulated Blast furnace Slag In Concrete, Journal of Emerging Trends in Engineering and Applied Sciences., Vol. 5, pp (2014). [5] Chander Garg and Ankush Khadwal, Behaviour of Ground Granulated Blast Furnace Slag and Limestone Powder as Partial Cement Replacement, International Journal of Engineering and Advanced Technology. Vol. 3, pp (August-2014) editor@iaeme.com

9 D. Mani Deep and N. A. Jabez [6] M. V. Krishna Rao, P. Rathish Kumar, Azhar M. Khan, A study on the influence of curing on the strength of a standard grade concrete mix, Architecture and Civil Engineering, Vol.8, No 1, 2010, pp [7] Sonali K. Gadpalliwar and R. S. Deotale., To Study the Partial Replacement of Cement by GGBS & RHA and Natural Sand by Quarry Sand In Concrete, IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) Volume 11, Issue 2 Ver. II (Mar- Apr. 2014) [8] Neeraja.D. Experimental Investigations on Strength Characteristics of Steel Fiber Reinforced Concrete, International Journal of Scientific & Engineering Research Volume 4, Issue 2, February [9] Mr. Nikhil A. Gadge and Prof. S. S. Vidhale., Mix Design of Fiber Reinforced Concrete (FRC) Using Slag & Steel Fiber, International Journal of Modern Engineering Research (IJMER), Vol. 3, Issue. 6, Nov - Dec [10] M. Adams Joe., An Experimental Investigation on the Effect of GGBS & Steel Fiber in High Performance Concrete, International Journal of Computational Engineering Research, Vol 04,Issue, 4, April editor@iaeme.com