EXPERIMENTAL STUDIES ON EFFECTIVE WAY OF UTILIZING SUGARCANE BAGASSE ASH AS SUPPLEMENTARY CEMENTITIOUS MATERIAL IN CONCRETE

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 6, June 2018, pp , Article ID: IJCIET_09_06_079 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed EXPERIMENTAL STUDIES ON EFFECTIVE WAY OF UTILIZING SUGARCANE BAGASSE ASH AS SUPPLEMENTARY CEMENTITIOUS MATERIAL IN CONCRETE Yashwanth M K Associate Professor, Department of Civil Engineering, Maharaja Institute of Technology Mysore, Mandya, Karnataka, India B.G. Nareshkumar Professor, Department of Civil Engineering, Maharaja Institute of Technology Mysore, Mandya, Karnataka, India Yashwanth R Engineer, Hindustan Construction Company Limited, Ramban, Jammu Kashmir, India Gagan B Post Graduate Student, Department of Civil Engineering, K S College of Engineering & Management, Bengaluru, Karnataka, India ABSTRACT This experimental study deals with assessing the potential of sugarcane bagasse ash (SBA) as a partial replacement for cement in concrete mixes. The concrete mix is designed as per IS 10262: 2009 for target strength of 20MPa. The cement is partially replaced with 5%, 10%, 15% and 20% of the SBA. The fresh properties of concrete mixes are assessed by conducting slump cone test. The slump increases with increase in percentage of replacement of SBA and reaches 185mm at 20% replacement of SBA in concrete mix. The hardened properties such as compressive and split tensile strength were carried out at 7, 28 & 90 and 28 & 90 days respectively. Both compressive and split tensile strength of concrete mixes increased with increase in percentage of replacement of SBA up to 15%, further at 20% replacement level the strength decreases. Based on test results, it can be inferred that 15% replacement of the cement with SBA can be considered as optimum replacement level, considering its fresh and hardened properties. The micro structural analysis revealed that, interfacial transition zone of concrete containing 15% SBA is better than control mix. Key words: Controlled mix; Sugarcane Bagasse ash (SBA); Fresh properties; Hardened properties; micro structural analysis editor@iaeme.com

2 Experimental Studies on Effective Way of Utilizing Sugarcane Bagasse Ash as Supplementary Cementitious Material in Concrete Cite this Article: Yashwanth M K, B.G. Nareshkumar, Yashwanth R and Gagan B, Experimental Studies on Effective Way of Utilizing Sugarcane Bagasse Ash as Supplementary Cementitious Material in Concrete, International Journal of Civil Engineering and Technology, 9(6), 2018, pp INTRODUCTION Due to rapid increase in the construction activities, the consumption of cement is increased in recent times. India is the second largest cement producing country in the world, accounting for 7-8% of global cement production with an effective capacity of 234 million tones/year [1].Increased use of cement in construction activities leads to environmental problems such as depletion of natural resources, emission of CO 2 and consumption of huge quantity of energy. Therefore it is necessary to consider, the use of supplementary cementitious materials in the production of concrete mixes. Fly ash, ground granulated blast furnace slag, silica fume and rice husk ash are some of the supplementary cementitious materials that are widely used as partial replacement for cement in concrete mixes. Studies demonstrated the satisfactory performance of concrete mixes with these materials at optimum replacement level; however the availability of these materials at certain locations hinders its usage in concrete mixes and emphasizes to consider other pozzolanic material such as sugarcane bagasse ash (SBA) that can be used as partial replacement for cement. SBA is a byproduct from sugarcane industries obtained as fibrous ash collected after burning of bagasse in cogeneration boiler. At present, SBA is directly disposed as landfill, which causes severe environmental problem. Hence the utilization of SBA in concrete mixes is considered as viable option as it resolves the disposal problem and also reduces the consumption of cement to certain extent. The presence of amorphous silica content endorses the authors perception on utilization of SBA in concrete. The sample of sugarcane bagasse ash was found to have completely burnt silica-rich fine particles and two different types of carbon-rich fibrous particles and fine fibrous particles as shown in Fig 2. The fine burnt particles have higher pozzolanic activity and carbon rich fibrous are inert in nature. Complete removal of carbon rich fibrous unburnt particles by sieving through 300µm sieve and further grinding to cement fineness in ball mill was suggested as the best strategy for producing the sugarcane bagasse ash based blended cement [2]. In our experimental study, carbon rich fibrous unburnt particles is removed by sieving through 300µm sieve, further it is grinded and sieved through 90µm IS sieve. Hence passing 90 µm SBA is used in our experimental study as pozzolanic material. 2. MATERIAL AND METHODS Concrete mixes are made by using coarse aggregate, fine aggregate along with cement and bagasse ash as binders. Crushed granite stone are used as coarse aggregate and river sand particle size < 4.75mm as fine aggregate. This section presents the properties of materials used in the experimental program as well as the procedures adopted to perform each of the tests Physical Properties of Cement The physical properties of cement are determined as per IS: 4031 (part1)-1996[3]. The results are based on two trials and are listed in Table editor@iaeme.com

3 Yashwanth M K, B.G. Nareshkumar, Yashwanth R and Gagan B 2.2. Physical Properties of SBA The physical properties of SBA are determined as per IS: [4]. The test is done as specified in IS: [3] except that in place of cement, a mixture of pozzolana and cement in the proportion 0.2 N : 0.8 by weight, blended intimately shall be used. The results are based on two trials and are listed in Table 2 Table 1 Physical properties of cement Sl no. Attributes Results Requirements as per IS: [5] 1 Type of cement OPC 53 grade 2 Normal Consistency 29% 3 Setting time Initial setting time Final setting time 234 min 298 min 4 Soundness 1mm 10mm 5 Specific gravity to 4 6. Fineness of cement (by sieve analysis) 4.88% 10% 7 28 Days Compressive Strength (MPa) Min 30 mins Max 600 mins Table 2 Physical properties of 90µ passing SBA blended with cement Sl No Tests Results 1. Normal Consistency (%) 34 2 Initial setting time (min) 295 min 3. Final setting time (min) 355 min 4 Fineness by sieve analysis (%) Specific gravity Chemical Composition of SBA The test results listed in Table 3 are based on the test reports of chemical analysis furnished by an ISO certified laboratory. The SBA are tested in three different forms viz., in raw state (collected SBA directly tested), SBA sieved through 300 micron (µ) sieve and grinded SBA sieved through 90µ sieve. The chemical analysis of SBA reveals, more than 70% of silica content in all three samples. The carbon content in the raw sample is marginally high as compared to other samples. As per IS: 3812(part1)-2013[6]specifications the combined chemical composition of SiO 2 +Al 2 O 3 +Fe 2 O 3 should be 70% which satisfies the pozzolanic nature of SBA, that can be classified as class F pozzolana as it satisfies the aforementioned codal provisions. Sample Silica as SiO 2 (%) Table 3 Chemical properties of SBA Alumina as Al 2 O 3 (%) Ferrous as Fe 2 O 3 (%) Calcium CaO (%) Loss on Ignition (LOI) % Raw Passing 300µ Grinded SBA Passing 90µ editor@iaeme.com

4 Experimental Studies on Effective Way of Utilizing Sugarcane Bagasse Ash as Supplementary Cementitious Material in Concrete 2.4. Micro structural Properties of SBA X-ray diffraction (XRD) Analysis Mineralogical analysis of bagasse ash carried out by X-ray diffraction analysis as shown in Fig.1 (a). The material essentially consists of an amorphous silica structure with a wide scattering peak (hump) centered at 2Ɵ values of about Figure 1 (a) X-Ray diffraction (XRD) & Fig.1 (b) SEM analysis of sugarcane bagasse ash Scanning Electron Microscope (SEM) Analysis Morphology study of bagasse ash is carried out by SEM (Scanning Electron Microscope) is shown in Fig 1(b). It reveals that SBA samples are composed of grains with different shape they are spherical, prismatic, fibrous and irregular. Prismatic particles consist of Si & O, spherical particles contain Si & O as well as some other minor compounds, fibrous particle consists of only carbon and particles with irregular shape are rich in silica Physical Properties of Aggregates The physical properties of fine and coarse aggregates are determined based on the procedures specified in IS: 2386 Parts (1 to 4)-1963 [7]. The test results along with gradation curves are listed in Table 4. Sl no Table 4 Physical Properties of Fine Aggregates Tests Fine Aggregate Results Coarse Aggregate Results 1. Specific gravity Fineness modulus Silt content 1% 4. Water Absorption 1% 0.5% Shape test Flakiness Index Elongation Index % 24.53% 6 Crushing value 20.97% 2.6. Mix Constituents The M20 grade mix is designed as per IS: [8] by considering the properties of aggregates. SBA is used as mineral admixtures. The mix proportion corresponds to 1: 2.2: 3.55, with water to binder ratio as 0.53 and no chemical admixtures were used. Coarse aggregates passing 20mm and retained on 4.75mm are used, so as to be in compliance with the prerequisite for making concrete. Aggregates are used in SSD condition and the details of mix constituents are given in Table editor@iaeme.com

5 Compressive Strength in MPa SLUMP VALUE IN MM Yashwanth M K, B.G. Nareshkumar, Yashwanth R and Gagan B Table 5 Mix Constituents (Kg/m 3 ) Mix Designation Cement in % of SBA Kgs SBA in Kgs Fine aggregate in Kgs Coarse aggregate in Kgs W/c ratio Water Content in Litres CM SBA SBA SBA SBA RESULTS AND DISCUSSIONS 3.1. Fresh Properties of Concrete The workability of the concrete mixes are assessed by conducting slump test as per IS: [9].The slump value of the designated mix constituents are listed in Table 6. The slump increases with increase in the SBA content and it reaches to maximum value of 185mm at 20% replacement level. The introduction of SBA improves workability in the mixes and this can be attributed to the lubricating effect of the SBA due to its spherical shape. Table 6 Slump values for mix constituents Mix Designation Slump in mm CM 110 5SBA SBA SBA SBA Slump in mm CM 5 S B A 1 0 S B A 1 5 S B A 2 0 S B A MIX DESIGNATION 3.2. Compressive Strength of Concrete The cubes are removed from curing tank prior to testing, dried and tested as per IS: [10].Three cubes are tested at 7, 28 and 90 days, for each mix variants. The compressive strength of bagasse ash blended concrete increases with increase in SBA content up to 15% replacement by 27.28%at 7 days as compared to controlled mix as depicted in Fig CM 5SBA 10SBA 15SBA 20SBA Mix Designation 7 days Compressive Strength in MPa 28 days Compressive Strength in MPa 90 days Compressive Strength in MPa Figure 2 Compressive strength of cubes at 7, 28 and 90 Days editor@iaeme.com

6 Split tensile strength in MPa Experimental Studies on Effective Way of Utilizing Sugarcane Bagasse Ash as Supplementary Cementitious Material in Concrete This early strength development in SBA blended concrete is due to the silica content, fineness, amorphous phase and degree of reactivity of SBA and pozzolanic reaction. The findings are consistent with results of SBA blended concrete (K.Ganesan et.al, 2007 ;). At 28 and 90 days also there will be increase in compressive strength value of SBA blended concrete at 15% replacement of SBA by 9.9% for 28 days and 6.91% for 90 days as compared to controlled mix. (K.Ganesan et.al, 2007[11]; Nuntachai Chusilpet.al, 2009 [12]; A. Baharudeen et.al, 2015 [13]). The reduction in compressive strength value of SBA blended concrete beyond 15% replacement of SBA is due to dilution effect caused by higher percentage of replacement of OPC with SBA (A. Baharudeen et.al, 2015 ;). 3.3 Split tensile Strength of concrete From Fig. 3, it is observed that increase in SBA content up to 15% replacement there is a higher tensile strength value of SBA blended concrete by 1.12% at 28 days and 3.94% at 90 days compared to controlled mix, beyond that there is a reduction in split tensile strength. The findings are consistent with other results of SBA blended concrete (K.Ganesan et.al, 2007[11]; R.Srinivasan and K. Sathiya 2010[14]) CM 5SBA 10SBA 15SBA 20SBA Mix Designation 28 days split tensile strength in MPa 90 days split tensile strength in MPa Figure 3 Split tensile strength at 28 & 90Days 3.4. Micro Structural Analysis of Concrete Micro structural analysis of controlled mix and optimum percentage i.e., 15% of SBA based concrete is carried out by Scanning Electron Microscope (SEM) analysis at 28 days and 90 days. Figure 4 Comparison between CM and 15SBA at 28 and 90 days of curing editor@iaeme.com

7 Yashwanth M K, B.G. Nareshkumar, Yashwanth R and Gagan B From the Fig.4 (a) and 4(c), there is a formation of interfacial transition zone which is defined as the gap length between the aggregate and cement paste in controlled mix and the microstructure is not so homogeneous both at 28 and 90 days. This can be attributed to formation of interfacial transition zone. From the Fig.4(b) and 4(d), there was no gap to be measured between the aggregate and cement paste i.e., interfacial transition zone and the microstructure was homogeneous, this can be attributed to the pore refinement, which lead to an improved microstructure at the interfacial zone at 28 and 90 days. In general and it can be observed that SBA based concrete shows a better performance than the controlled concrete. SBA replacement level in concrete lead to increase in the densification of interfacial zone as expected due to its fineness and pozzolanic reactivity. 4. CONCLUSIONS From the present investigation, the following conclusion were drawn Raw bagasse ash has high loss on ignition (LOI) value due to the presence of unburnt coarse fibrous carbon particles which induces low pozzolanic activity whereas processed SBA has low loss on ignition (LOI) value due to the removal of unburnt fibrous carbon particles which induces high pozzolanic activity than the minimum required. The sample of SBA was found to have prismatic, spherical and irregular particles which were observed from the scanning electron microscope in the microstructure study. SBA up to 15% replacement by weight of cement is found to be better substitute for cement for improving workability of concrete. From the compressive strength results, it is found that on 15% of SBA replacement with cement will yield better compressive strength as compared to controlled mix. From the split tensile strength results, it is found that on 15% of SBA replacement with cement will yield better tensile strength as compared to controlled mix. From the micro structural results, at 15% of SBA replacement level the microstructure of interfacial transition zone was homogeneous without the presence of wall effect between the aggregate and the paste matrix. Thus, we can conclude that addition of SBA up to 15% as substitute for cement to produce concrete is acceptable. REFERENCES [1] Cement manufacturers association (CMA) New Delhi, 52 nd annual report , [2] A. Baharudeen and Manu Santhanam, Influence of different processing methods on the pozzolanic performance of sugarcane bagasse ash, Cement and Concrete Composites, Volume 56, 2015, [3] IS: 4031 (Part I-VI)-1988, Methods of physical tests for hydraulic cement, Bureau of IndianStandards, New Delhi. [4] IS: , Methods of test for pozzolanic materials, Bureau of Indian Standards, New Delhi. [5] IS: , ordinary Portland cement-53 grade specifications, Bureau of Indian Standards, New Delhi. [6] IS: 3812 (part-1): 2013, Specification for pulverized fuel Ash for use as pozzolona in cement, cement mortar and concrete, Bureau of Indian Standards, New Delhi editor@iaeme.com

8 Experimental Studies on Effective Way of Utilizing Sugarcane Bagasse Ash as Supplementary Cementitious Material in Concrete [7] IS: 2386 (part 1-4): 1984, Methods of test for aggregates for concrete, Bureau of Indian Standards, New Delhi. [8] IS: , Concrete mix Proportioning Guidelines, Bureau of Indian Standards, New Delhi. [9] IS: , Methods of sampling and analysis of concrete, Bureau of Indian Standards, New Delhi. [10] IS: , Method of Tests for Strength of Concrete,Bureau of Indian Standards, New Delhi. [11] K. Ganesan, K. Rajagopal & K Thangavel, Evaluation of bagasse ash as supplementary cementitious material, Cement and Concrete Composites, Volume 29, 2007, [12] Nuntachai Chusilp, Chai Jaturapitakkul and Kraiwood Kiattikomol., Utilization of bagasse ash as a pozzolanic material in concrete, Construction and Building Materials, 23 (2009) pp: [13] A. Baharudeen, Deepak Kanraj V, Gokul Dev and Manu Santhanam, Performance evaluation of sugarcane bagasse ash blended cement in concrete, Cement and Concrete Composites, Volume 59, 2015, [14] R.Srinivasan and K.Sathiya, Experimental study on bagasse ash in concrete, International journal for service learning in engineering, Vol. 5, No.2 (2010) pp: editor@iaeme.com