ZERO CEMENT CONCRETE WITH UPGRADED PROPERTIES

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 7, Issue 4, July-August 2016, pp Article ID: IJCIET_07_04_040 Available online at ISSN Print: and ISSN Online: IAEME Publication ZERO CEMENT CONCRETE WITH UPGRADED PROPERTIES Muazam Akthar S Department of Civil Engineering, Velammal Engineering College, Chennai, India Srinivasan R Department of Civil Engineering, Velammal Engineering College, Chennai, India Yashwanth B Department of Civil Engineering, Velammal Engineering College, Chennai, India ABSTRACT Zero Cement Concrete is an improved version of Geo-polymer Concrete wherein the thermal activation of the binding materials such as Fly Ash and Ground Granulated Blast Furnace Slag (GGBS) is done with the help of alkaline solution namely Sodium Hydroxide (NaOH) and Sodium Silicate (Na 2 SiO 3 ).Additionally, Steel Slag was partially replaced with Blue Metal in order to make it both durable and economical. This Paper represents the experimental investigation carried by varying alkaline solution and steel slag on the mechanical and durable properties of Zero Cement Concrete.M25 Grade was chosen for 8 Molarity. The alkaline solution has been chosen in the varying ratio of 2, 2.5 and 3. Similarly Steel Slag was used in an incremental order of 20%.The performance of Geo-polymer Concrete in terms of workability was in a good range. The Prepared Samples were cured under ambient temperature. The tests were carried in accordance with Bureau of Indian Standard Codes. The Results revealed that the maximum strength was obtained at the optimum alkaline solution ratio of 2.5 and 60% replacement of Steel Slag. The Test results were far superior to the conventional M-25 Grade Concrete. Key words: Geo-Polymer, Fly Ash, GGBS, Steel Slag, Alkaline Solution Cite this Article: Muazam Akthar S, Srinivasan R and Yashwanth B, Zero Cement Concrete with Upgraded Properties. International Journal of Civil Engineering and Technology, 7(4), 2016, pp editor@iaeme.com

2 Zero Cement Concrete with Upgraded Properties 1. INTRODUCTION This experimental study has focused on using industrial waste materials in order to reduce the CO 2 emission which otherwise happens in the traditional concrete. Many statistics has derived to a conclusion that the construction firm, which manufacture cement has been the second largest CO 2 emitter after petroleum and oil industry [1]. This in turn means that, civil engineers are directly responsible for the depletion of Ozone layer. Petrochemical and power plant industries which are considered the most important energy producing enterprise emit huge amount of green house gases. These industries cannot compromise on its production and hence construction firms can make use of the byproducts produced by these industries. The Geo-Polymer technology was first introduced by Davidovits in 1978 [2]. In this project, the sole aim is to produce concrete without conventional materials. The cement is replaced with industrial waste such as Fly Ash, Ground Granulated Blast Furnace Slag (GGBS) [3]. The conventional Blue Metal is replaced in percentage with Steel Slag [4]. The alkaline solution is used to enhance polymerization process, wherein the solution is important for dissolving of Si and Al atoms to form geo-polymer precursors and finally alumino-silicate material. 2. MATERIALS USED The following materials have been used in this experimental study 1. Fly Ash (Class F) of specific gravity 2.00 collected from ONGC Plant, Chennai. 2. GGBS obtained from RMC Plant was used as 50% replacement of cement. 3. Steel Slag collected from Tuticorin Steel Plant with specific gravity Alkaline Solution Specific gravity of i) Sodium Hydroxide (NaOH) = 1.15 ii) Sodium Silicate (Na2SiO3) = Fine Aggregates were used as per IS Specifications 6. Coarse Aggregate of 20mm were used as per IS Specifications 7. Distilled Water 8. Super plasticizer Conplast SP-430 Tests were conducted on specimen of standard size as per IS: and IS: MIX DESIGN OF GEO POLYMER CONCRETE The assumed Grade of concrete is M25. The water to fly ash ratio is taken as The water content per cubic meter of concrete is taken as 108kg. Volume of Fine Aggregate is taken as 33% of the total volume of aggregates. The activator solution to the binder ratio is taken as 0.4. The amount of super plasticizer is considered as 1.5% of the total volume of the binder in order to increase the workability. The detailed mix design has been given in Appendix 1 of the Annexure. 4. EXPERIMENT METHODOLOGY In this project cement has been replaced with 100% of Fly-ash and with 50-50% fly-ash and GGBS respectively. The coarse aggregate has been replaced with 20 mm Steel Slag in successive percentage of 20. The polymerization process has been carried out with the help of alkaline solution i.e. sodium hydroxide (NaOH) of 8M and sodium silicate (Na2SiO3) solution. For 8M of NaoH, 320 g of sodium hydroxide pellets was dissolved in water. The mass of NaOH solids in a solution will vary depending on the concentration of the solution expressed in terms of molar, M. The pellets of NaOH are dissolved in one liter of water for the required concentration. Mixing the 2 solutions together will instigate the polymerization process [5]. This Alkaline solution should be left unused for next 24 hours. The dry aggregates are mixed in a dry pan for about 3 minutes and the alkaline solution is added in their respective ratios of 2, 2.5 and 3.This mixture is mixed for 5 minutes and super plasticizer is added to editor@iaeme.com

3 Muazam Akthar S, Srinivasan R and Yashwanth B it. This will enable us to give the optimum ratio of Alkaline solution and percent of Steel Slag required for obtaining superior values i.e., both physical and chemical properties of concrete [6]. The casted specimen is made to undergo ambient curing for 28 days. All the aggregate tests, fresh concrete tests and hardened concrete tests have to be performed. ed. These studies are essential as per IS Codes in order to justify fly-ash/ GGBS is a good replacement for cement. 5. RESULTS AND DISCUSSION 5.1. Compressive Strength Figure 1 Concrete Cubes and Cylinders Casted The compressive strength is the most important property of the hardened concrete. The ambient cured sample undergoes the compression test on 7 th and 28 th day. The compression strength mainly depends on two factor, they are Aging and Degree of compaction. The Geo-Polymer sample (50-50% Fly Ash and GGBS) showed that they attain the required compressive strength on the 7 th days of ambient curing, when the Steel Slag is replaced for 60% with blue metal. The 7 th day compressive strength was MPa for 2.5 Alkaline Solution ratio. The same compressive strength was obtained by conventional concrete only on 28 th day of curing. Whereas the Geo-Polymer Concrete strength on 28 th day was recorded as 42.68MPa, which proved it to be more than 40% then that of conventional concrete. The test results for all samples are shown in the Figure 1 and Figure 2. The detailed observations are given in Appendix 2 of the Annexure. Figure 2 Compressive Strength at 100% Fly Ash Replacement editor@iaeme.com

4 Zero Cement Concrete with Upgraded Properties Figure 3 Compressive Strength at 50%Fly Ash & 50% GGBS Replacement 5.2. Split Tensile Strength The Tensile strength of Geo-Polym Polymer Concrete is directly known from Split Tensile test. The test depicted that due to high tensile property of Steel Slag the Tensile Strength of Geo-Polymer Concrete seemed to increase with increasing percentage replacement of Steel Slag with Blue Metal up to 80 %, and it started to fall later on. For 60% replacement a tensile strength of was obtained in 50-50% Fly Ash and GGBS sample of 2.5 alkaline solution ratio. The tensile strength of Geo-Polymer Concrete is 10% more than that of conventional concrete. The test results for all l samples are shown in the Figure 3 and Figure 4. The detailed observations are given in Appendix 3 of the Annexure. Figure 4 Split Tensile Strength at 100% Fly Ash Replacement editor@iaeme.com

5 Muazam Akthar S, Srinivasan R and Yashwanth B Figure 5 Split Tensile Strength at 50% Fly Ash and 50% GGBS Replacement 5.3. Flexural Strength Prisms of size 100 mm x 100 mm x 500 mm were cast for required mix proportion. After curing it in an ambient temperature, the prisms were tested. ted. The test results revealed that, at 100% of Fly Ash replacement against cement, the maximum flexural strength was recorded at 60% of steel slag replacement for all the three Alkaline Solution ratios. The same scenario was observed at 50% Fly Ash and 50% GGBS replacement against cement, but comparatively much higher Flexural Strength. Amongst the three Alkaline Solution ratios of 2, 2.5 & 3, the highest flexural strength was obtained in the AS ratio of 2.5 as 5.472MPa. Therefore it can be clearly said tha at AS ratio of 2.5 in the binder mix of 50% Fly Ash and 50% GGBS can yield the highest Flexural Strength at 60% of steel slag replacement. The test results for all samples are shown in the Figure 5 and Figure 6. The detailed observations are given in Appendix 4 of the Annexure. Figure 6 Flexural Strength at 100% Replacement of Fly Ash editor@iaeme.com

6 Zero Cement Concrete with Upgraded Properties Figure 7 Flexural Strength at 50% Fly Ash and 50% GGBS Replacement 5.4 Water Absorption Test The saturated water absorption test was performed on cube specimens of size 100 mm after 28 days of curing. The results of the test showed that the level of water absorption by the concrete is much lower in 50% Fly Ash and 50% GGBS replaced concrete compared to the conventional concrete. The water absorption of the above said binder mix and steel slag replacement of 60%, had a value of 0.96 as the water absorption percentage. Thus it was well under 5% as stipulated by the ASTM C norms. Thereby it can be concluded that the concrete isn t prone to excessive water absorption. The test results for all samples are shown in the Figure 7. The detailed observations are given in Appendix 5 of the Annexure. 3.5 Water Absorption Test Water Absorbed(%) % Flyash & 50% GGBS Replaced concrete Conventional M25 Concrete Figure 8 Water Absorption Test 5.5. Workability Test This experiment illustrated that the fresh Geo-Polymer concrete is viscous in nature. The workability was good due to the presence of the sodium silicate solution. During mixing, the water present in the GGBS and Fly Ash will help mix with the mixture. The optimum slump value of 95mm was obtained in the editor@iaeme.com

7 Muazam Akthar S, Srinivasan R and Yashwanth B 50% replacement of cement by fly ash and GBBS respectively. The slump test of Geo-Polymer concrete is briefed in the Table 1. Table 1 Slump Test Geo-Polymer Mix Slump value for different Alkaline solution ratio % Fly Ash Replacement % Fly Ash and 50% GGBS Fire Resistance Test To check the fire rating of the concrete, the concrete cubes are burnt in open fire for half hour and then the cubes are air cured, after which the compressive strength is checked. The surface defects, change in strength and other characters are studied. These data s will help the designer to design the building accordingly. From this test we have found that the Strength of Geo polymer concrete loses 10% of its original compressive strength after burning. The test results for all samples are shown in the Figure 8. The detailed observations are given in Appendix 6 of the Annexure. Compressive Strength % Flyash and 60% Steel Slag at Unburnt condition Fire Resistance Test 100% Flyash and 60% Steel Slag at Burnt condition 50% Fly Ash - 50% GGBS and 60% Steel Slag at Unburnt condition 50% Fly Ash - 50% GGBS and 60% Steel Slag at Burnt condition AS Ratio 2 AS Ratio 2.5 AS Ratio 3 Figure 9 Fire Resistance Test 5.7. Rapid Chlorine ion Penetration Test The rapid chloride penetration test (RCPT) was performed as per ASTM C 1202 to determine the electrical conductance of the specimens at the age of 28 days curing and to provide a rapid indication of its resistance to the penetration of chloride ions [7]. The results of the test revealed that the amount of charge passed through the concrete, in both the cement replaced cases and for all steel slag replacement cases, was Very Low and Negligible. Thus the concrete is not prone to any chemical attack. The test results are tabulated in Table 2. The detailed observations are given in Appendix 7 of the Annexure editor@iaeme.com

8 Zero Cement Concrete with Upgraded Properties 6. CONCLUSION Table 2 Rapid Chloride Ion Penetration Test S.No MC Charge passed (coulombs) Chloride ion penetrability 1 St 0 54 Negligible 2 St Negligible 3 St Negligible 4 St Very Low 5 St Very Low 6 St Low 1. Maximum strength and durability is obtained in Geo-Polymer concrete when alkaline solution ratio of 2.5, full cement replacement by 50-50% of fly ash and GGBS and 60% of Steel Slag replacement are used. 2. The required strength is obtained on the 7 th day under ambient curing. 3. The tensile property of concrete is increased due to the presence of Steel Slag. 4. All the physical properties of Geo-Polymer concrete of grade M25 is better than the conventional concrete of Grade M25 REFERENCES [1] Jay S. Gregg, Robert J. Andres, and Gregg Marlan, Emissions pattern of the world leader in CO2 emissions from fossil fuel consumption and cement production, Geophysical Research Letters, Volume 35, L08806, DOI: /2007GL032887, 20 [2] Davidovits, J, High Alkali Cements for 21 st Century Concretes in Concrete Technology, Past, Present and Future, Proceedings of V.Mohan Malhotra Symposium, Editor: P.Kumar Metha, ACI SP-144,1994, pp [3] Malhotra, V.M, Making Concrete Greener with Fly Ash, ACI Cocrete International, 21, 1999, pp [4] Bhoi, A. Strength characteristic analysis of steel slag hydrated mix, National Institute of Technology, Rourkela 2009 [5] Davidovits, J, Soft Mineralogy and Geo-Polymers, Proceedings of the Geo-Polymer 88 International Conference, the Universite de Technologie, Compiegene, France 1988 [6] Vijay K, Kumutha R and Vishnuram B.G, (2012). Experimental Investigations on mechanical properties of Geo-Polymer Concrete composites, Asian journal of Civil Engineering (building and housing) 13(1) pp [7] Dr.K.Chinnaraju, et al Study On Concrete Using Steel Slag As Coarse Aggregate Replacement and Ecosand As Fine Aggregate Replacement, International Journal of Research in Engineering and Advanced Technology, 1 (3), June-July [8] Er. S.Thirougnaname and Dr. T.Sundararajan, Studies On Rice Husk Ash Cement Concrete. International Journal of Civil Engineering and Technology, 4(6), 2013, pp [9] H. Sudarsana Rao and Vaishali.G.Ghorpade, Strength Assessment of Blended Cement Concrete with Water Containing Sulphuric Acid. International Journal of Civil Engineering and Technology, 4(5), 2013, pp editor@iaeme.com

9 Muazam Akthar S, Srinivasan R and Yashwanth B ANNEXURE APPENDIX 1 MIX DESIGN CALCULATION The following mix design has been done for 100% replacement of Fly-ash in place of cement. Grade Designation - Geo-polymer concrete does not have any grade like traditional concrete. But, we have taken traditional concrete s M25 Mix proportion for making GPC in order to check the strength difference between Geo-polymer concrete and traditional concrete. Type of Fly-ash = Class F Specific Gravity of Fine Aggregate = 2.7 Minimum Fly-ash =400 kg / m 3 Maximum water Fly-ash ratio = 0.27 Steps for calculation 1. Target Mean Strength = 25 + (5 X 1.65) = Mpa 2. Calculation of excess water: W/F=0.27 Water content = 0.27X400= 108 kg /m 3 3. Calculation of cement content: Water Fly-ash ratio = 0.27 Water content per cum of concrete = 108 kg Fly-ash content = 108/0.27 = 400 kg / m 3 4. Calculation for C.A. & F.A.: Volume of F.A. = (1/4) X 1.57 = m 3 Weight of F.A =0.3925x1475 =578.9 kg / m 3 Say 580 kg / m 3 Volume of C.A. = (2/4) X 1.57 = m 3 Weight of C.A =0.785x1500 = kg / m 3 Say 1180 kg / m 3 * The Steel Slag replacement ratios are calculated based on the weight of the C.A Obtained. 5. Alkaline activator The optimum ratio of activator solution to binder is taken as 0.4. Alkaline solution / Binder=0.4 Alkaline solution = 0.4x400 Alkaline solution = 160 kg/m 3 Alkaline solution is the mixture of Sodium silicate and sodium hydroxide in ratio 2, 2.5 and 3 respectively. For Quantity Estimate, ratio of 2.5 is adopted editor@iaeme.com

10 Zero Cement Concrete with Upgraded Properties Sodium silicate/ Sodium hydroxide = Molarity is taken as optimum value, but it can be varied between 8M to 16 M. For 8 Molarity, 320 gram of NaOH (solid) is mixed in one litre of distilled water. Molecular weight of NaOH is equal to 40 gram per Molarity i.e., 40X8= 320 gram. Na 2 Sio 3 /NaOH= Super plasticizer For NaOH = (160/3.5) x1= Say 46 kg/m 3 For Na 2 Sio 3 = (160/3.5) x2.5= Say 115 kg/m 3 Super plasticizer = (1.5)/100 x 400 = 6 kg/m 3 *In case of 50 % Fly-ash + 50 % of GGBS the same mix design is followed *The Mix Ratios of various materials are Tabulated below in Table 3 and Table 4. Table 3 Mix for GPC (100% Fly Ash) Materials Kg/m 3 Grade 20mm C.A Fine Flyash /NaOH 2 Sio 3 Plasticizer Na 2 Sio 3 Extra Blue Steel NaOH Na sand Water Metal Slag M M M Table 4 Mix for GPC (50-50 GGBS and Fly Ash) Materials Kg/m 3 Grade 20mm C.A Fine Flyash: Na 2 Sio 3 Extra Blue Steel NaOH Na sand GGBS /NaOH 2 Sio 3 Plasticizer Water Metal Slag M : M : M : APPENDIX 2 COMPRESSIVE STRENGTH RESULTS Table 5 100% Fly Ash Replacement with AS ratio 2 7 day Compressive Strength 28 day Compressive Strength 1 St St St St St St editor@iaeme.com

11 Muazam Akthar S, Srinivasan R and Yashwanth B Table 6 100% Fly Ash Replacement with AS ratio day Compressive Strength 28 day Compressive Strength 1 St St St St St St Table 7 100% Fly Ash Replacement with AS ratio 3 7 day Compressive Strength 28 day Compressive Strength 1 St St St St St St Table 8 50% Fly Ash and 50% GGBS Replacement with AS ratio 2 7 day Compressive Strength 28 day Compressive Strength 1 St St St St St St Table 9 50% Fly Ash and 50% GGBS Replacement with AS ratio day Compressive Strength 28 day Compressive Strength 1 St St St St St St Table 10 50% Fly Ash and 50% GGBS Replacement with AS ratio 3 7 day Compressive Strength 28 day Compressive Strength 1 St St St St St St editor@iaeme.com

12 Zero Cement Concrete with Upgraded Properties APPENDIX 3 SPLIT TENSILE STRENGTH TEST RESULTS Table % Fly Ash Replacement with AS ratio 2 7 day Split Tensile Strength 28 day Split tensile Strength 1 St St St St St St Table % Fly Ash Replacement with AS ratio day Split Tensile Strength 28 day Split tensile Strength 1 St St St St St St Table % Fly Ash Replacement with AS ratio 3 7 day Split Tensile Strength 28 day Split tensile Strength 1 St St St St St St Table 14 50% Fly Ash and 50% GGBS Replacement with AS ratio 2 7 day Split Tensile Strength 28 day Split tensile Strength 1 St St St St St St editor@iaeme.com

13 Muazam Akthar S, Srinivasan R and Yashwanth B Table 15 50% Fly Ash and 50% GGBS Replacement with AS ratio day Split Tensile Strength 28 day Split tensile Strength 1 St St St St St St Table 16 50% Fly Ash and 50% GGBS Replacement with AS ratio 3 7 day Split Tensile Strength 28 day Split tensile Strength 1 St St St St St St APPENDIX 4 FLEXURAL STRENGTH TEST RESULTS Table % Fly Ash Replacement with AS ratio 2 S.No Mix Combination Flexural Strength 1 St St St St St St Table % Fly Ash Replacement with AS ratio 2.5 S.No Mix Combination Flexural Strength 1 St St St St St St editor@iaeme.com

14 Zero Cement Concrete with Upgraded Properties Table % Fly Ash Replacement with AS ratio 3 S.No Mix Combination Flexural Strength 1 St St St St St St Table 20 50% Fly Ash and 50% GGBS Replacement with AS ratio 2 S.No Mix Combination Flexural Strength 1 St St St St St St Table 21 50% Fly Ash and 50% GGBS Replacement with AS ratio 2.5 S.No Mix Combination Flexural Strength 1 St St St St St St Table 22 50% Fly Ash and 50% GGBS Replacement with AS ratio 3 S.No Mix Combination Flexural Strength 1 St St St St St St APPENDIX 5 WATER ABSORPTION TEST RESULTS Table % Fly Ash Replacement Composition Water Absorbed (%) 50% Flyash & 50% GGBS Replaced concrete 0.96 Conventional M25 Concrete editor@iaeme.com

15 Muazam Akthar S, Srinivasan R and Yashwanth B APPENDIX 6 FIRE RESISTANCE TEST RESULTS Table 24 Fire Resistance Test Geo-polymer mix Strength before burnt (N/mm2 ) Strength after burnt (N/mm2 ) 100% Replacement of Flyash and 60% replacement of Steel Slag AS Ratio AS Ratio AS Ratio % Fly Ash and 50% GGBS and 60% replacement of Steel Slag AS Ratio AS Ratio AS Ratio APPENDIX 7 RAPID CHLORIDE ION PENETRATION TEST RESULTS Table 25 RCPT at 50% Fly Ash and 50% GGBS Replacement S.No MC Charge passed (coulombs) Chloride ion penetrability 1 St 0 54 Negligible 2 St Negligible 3 St Negligible 4 St Very Low 5 St Very Low 6 St Low editor@iaeme.com