Dr. Shashi Kumara S R | Visvesvaraya Technological University (original) (raw)

Uploads

Papers by Dr. Shashi Kumara S R

International Journal of Advance Research and Innovative Ideas in Education, 2018

In this experiment the study of influence of polymer in reinforced High Performance Concrete (HPC... more In this experiment the study of influence of polymer in reinforced High Performance Concrete (HPC) beams was done. The polymer being used was Styrene Butadiene Rubber (SBR) Latex The specimen being used here is a rectangular beam section of 2100mm span with 200mm wide and 300mm deep. The beam was tested after 28 days of curing and was subjected to a two-point loading under the loading frame. The parameters studied were load deflection curve, post cracking strength, ductility factor and strength gain factor. The Post Cracking Strength for HPC was 0.0958 kN/mm2 and for MHPC was 0.1063 kN/mm2.The relative ductility factor 1.38. The strength gain factor was 14.715.

International Research Journal of Engineering and Technology, 2016

Admixture-Cement interaction in concrete is a complex blend of chemical and physical mechanism th... more Admixture-Cement interaction in concrete is a complex blend of chemical and physical mechanism that are independent. Every admixture at optimum dosage gives better results when used with cement. The proposed research work is aimed at testing compatibility of slag cement at different dosages with PCE based admixtures. It was found that The Combination 80% Cement With 20% GGBS Are More Compatible Compared To All The Optimum Dosage Combinations.

India is a subtropical country, which receives good amount of rain each year. Due to sudden and m... more India is a subtropical country, which receives good amount of rain each year. Due to sudden and massive urbanization, the availability and supply of water for domestic purpose has introduced new challenges in urban water supply. Rainwater harvesting is a sustainable and reliable approach to manage the water in urban areas. In the recent years, rainwater harvesting is as statutory mandate during construction approval. Pervious concrete is a application oriented special concrete product, which has been effectively used to manage the surface run off in the shoulder, parking lane and other highway applications. In the present experimental study, efforts are made to use the pervious concrete as filtration medium for rainwater harvesting. The mechanical properties and permeability of pervious concrete are studied. A filtration medium model has prepared to study the permeability.

In the following experiment, the study of influence of polypropylene fibers in reinforced High Pe... more In the following experiment, the study of influence of polypropylene fibers in reinforced High Performance concrete (HPC) beams was done. The dimensions of beam specimen were 200*300*2100mm. The beam was tested after 28 days of curing and was subjected to two point loading under the loading frame. The parameters studied were load-deflection curve flexural toughness, energy absorption capacity. The flexural toughness factor for HPC and PFRC was 9.55x10-3 and 11.79x10-3 .

In the present study, an unified method of HPC mix design was proposed for compressive strength r... more In the present study, an unified method of HPC mix design was proposed for compressive strength range of 50-60MPa. Puntke test was conducted to determine the optimized combination of Ordinary Portland Cement (OPC) and microsilica (MS). Dry packing test was performed to determine the most dense aggregate combination of different size classes. The results of cementitious materials and aggregates optimization were integrate and imported for the HPC mix design. The volume of surplus paste content was optimized by considering 10%, 15% and 20% additional paste and w/cm ratio of 0.34 and 0.36 in flow table test. Compressive strength and water penetration depth of different HPC mixes were used to substantiate the selection of optimized HPC mix. The Puntke test results indicated an optimized binary blend of 80% OPC and 20% of MS in total cementitious materials. The packing density of three sizes class aggregate blending was found to be 0.900. The mix with 15% surplus paste and 0.34 w/cm was considered as optimized HPC mix based on the recorded flow diameter of 550 mm, compressive strength of 59.15 MPa and least water penetration depth of 6.21mm.

In this experiment the study of influence of polymer in reinforced High Performance Concrete (HPC... more In this experiment the study of influence of polymer in reinforced High Performance Concrete (HPC) beams was done. The polymer being used was Styrene Butadiene Rubber (SBR) Latex The specimen being used here is a rectangular beam section of 2100mm span with 200mm wide and 300mm deep. The beam was tested after 28 days of curing and was subjected to a two-point loading under the loading frame. The parameters studied were load deflection curve, post cracking strength, ductility factor and strength gain factor. The Post Cracking Strength for HPC was 0.0958 kN/mm 2 and for MHPC was 0.1063 kN/mm 2 .The relative ductility factor 1.38. The strength gain factor was 14.715.

This paper presents an experimental study on the effect of presoaked lightweight aggregates (LWAs... more This paper presents an experimental study on the effect of presoaked lightweight aggregates (LWAs) for internal curing on water permeability, water absorption and resistance of concrete to chloride-ion penetration in comparison with those of a control concrete and a concrete with shrinkage reducing admixture (SRA) of similar water/cement ratios (w/c). In general, the concretes with LWA particles had initial water absorption, sorptivity and water permeability similar to or lower than those of the control concrete and the concrete with SRA. The charges passed, chloride migration coefficient and chloride diffusion coefficient of such concretes were in the same order as those of the control concrete and the concrete with SRA. However, the incorporation of the LWAs for internal curing reduced unit weight, compressive strength and elastic modulus of the concrete. Comparing the LWAs of different sizes for internal curing, finer particles were more efficient in reducing the shrinkage and generally resulted in less reduction in the unit weight, compressive strength, and elastic modulus. However, the increase in the more porous crushed LW particles in concrete seems to increase the penetration of chloride ions in the concrete. The concrete with SRA had initial water absorption, sorptivity, water permeability and resistance to chloride ion penetration comparable with those of the control concrete. The use of SRA in concrete does not affect the elastic modulus of the concrete, except for a minor influence on the compressive strength of the concrete.

India is a subtropical country, which receives good amount of rain each year. Due to sudden and m... more India is a subtropical country, which receives good amount of rain each year. Due to sudden and massive urbanization, the availability and supply of water for domestic purpose has introduced new challenges in urban water supply. Rainwater harvesting is a sustainable and reliable approach to manage the water in urban areas. In the recent years, rainwater harvesting is as statutory mandate during construction approval. Pervious concrete is a application oriented special concrete product, which has been effectively used to manage the surface run off in the shoulder, parking lane and other highway applications. In the present experimental study, efforts are made to use the pervious concrete as filtration medium for rainwater harvesting. The mechanical properties and permeability of pervious concrete are studied. A filtration medium model has prepared to study the permeability.

In the present study, an unified method of HPC mix design was proposed for compressive strength r... more In the present study, an unified method of HPC mix design was proposed for compressive strength range of 50-60MPa. Puntke test was conducted to determine the optimized combination of Ordinary Portland Cement (OPC) and microsilica (MS). Dry packing test was performed to determine the most dense aggregate combination of different size classes. The results of cementitious materials and aggregates optimization were integrate and imported for the HPC mix design. The volume of surplus paste content was optimized by considering 10%, 15% and 20% additional paste and w/cm ratio of 0.34 and 0.36 in flow table test. Compressive strength and water penetration depth of different HPC mixes were used to substantiate the selection of optimized HPC mix. The Puntke test results indicated an optimized binary blend of 80% OPC and 20% of MS in total cementitious materials. The packing density of three sizes class aggregate blending was found to be 0.900. The mix with 15% surplus paste and 0.34 w/cm was considered as optimized HPC mix based on the recorded flow diameter of 550 mm, compressive strength of 59.15 MPa and least water penetration depth of 6.21mm.

Our paper documents the effects of using steel fibres in latex modified concrete. The study was c... more Our paper documents the effects of using steel fibres in latex modified concrete. The study was carried out to record the different physical and mechanical properties of steel fibre reinforced latex modified concrete. Latex modified concrete is nothing but, conventional concrete made by replacing part of mixing water with latex. Polymer as an admixture can improve properties like higher strength and lower water permeability than the conventional concrete. Since, concrete is weak in tension, steel fibres have been added to concrete, to improve its characteristics in tension. The polymer concrete specimens with and without fibers were cast and tested to watch the improvement of certain mechanical and physical properties like compressive strengths, tensile strengths, and workability. Styrene Butadiene Rubber Latex polymer and hooked end steel fibres have been used for our study. 5% of SBR Latex and 0.5% of steel fibres have been used. The hardened properties of concrete were tested at 7 th and 28 th days. It was found that the given fibre dosage enhanced the early compressive strength of concrete but reduced the 28 days compressive strength. Steel fibers increase the tensile strength of concrete.

India is a subtropical country, which receives good amount of rain each year. Due to sudden and m... more India is a subtropical country, which receives good amount of rain each year. Due to sudden and massive urbanization, the availability and supply of water for domestic purpose has introduced new challenges in urban water supply. Rainwater harvesting is a sustainable and reliable approach to manage the water in urban areas. In the recent years, rainwater harvesting is as statutory mandate during construction approval. Pervious concrete is a application oriented special concrete product, which has been effectively used to manage the surface run off in the shoulder, parking lane and other highway applications. In the present experimental study, efforts are made to use the pervious concrete as filtration medium for rainwater harvesting. The mechanical properties and permeability of pervious concrete are studied. A filtration medium model has prepared to study the permeability.

International Journal of Advance Research and Innovative Ideas in Education, 2018

In this experiment the study of influence of polymer in reinforced High Performance Concrete (HPC... more In this experiment the study of influence of polymer in reinforced High Performance Concrete (HPC) beams was done. The polymer being used was Styrene Butadiene Rubber (SBR) Latex The specimen being used here is a rectangular beam section of 2100mm span with 200mm wide and 300mm deep. The beam was tested after 28 days of curing and was subjected to a two-point loading under the loading frame. The parameters studied were load deflection curve, post cracking strength, ductility factor and strength gain factor. The Post Cracking Strength for HPC was 0.0958 kN/mm2 and for MHPC was 0.1063 kN/mm2.The relative ductility factor 1.38. The strength gain factor was 14.715.

International Research Journal of Engineering and Technology, 2016

Admixture-Cement interaction in concrete is a complex blend of chemical and physical mechanism th... more Admixture-Cement interaction in concrete is a complex blend of chemical and physical mechanism that are independent. Every admixture at optimum dosage gives better results when used with cement. The proposed research work is aimed at testing compatibility of slag cement at different dosages with PCE based admixtures. It was found that The Combination 80% Cement With 20% GGBS Are More Compatible Compared To All The Optimum Dosage Combinations.

India is a subtropical country, which receives good amount of rain each year. Due to sudden and m... more India is a subtropical country, which receives good amount of rain each year. Due to sudden and massive urbanization, the availability and supply of water for domestic purpose has introduced new challenges in urban water supply. Rainwater harvesting is a sustainable and reliable approach to manage the water in urban areas. In the recent years, rainwater harvesting is as statutory mandate during construction approval. Pervious concrete is a application oriented special concrete product, which has been effectively used to manage the surface run off in the shoulder, parking lane and other highway applications. In the present experimental study, efforts are made to use the pervious concrete as filtration medium for rainwater harvesting. The mechanical properties and permeability of pervious concrete are studied. A filtration medium model has prepared to study the permeability.

In the following experiment, the study of influence of polypropylene fibers in reinforced High Pe... more In the following experiment, the study of influence of polypropylene fibers in reinforced High Performance concrete (HPC) beams was done. The dimensions of beam specimen were 200*300*2100mm. The beam was tested after 28 days of curing and was subjected to two point loading under the loading frame. The parameters studied were load-deflection curve flexural toughness, energy absorption capacity. The flexural toughness factor for HPC and PFRC was 9.55x10-3 and 11.79x10-3 .

In the present study, an unified method of HPC mix design was proposed for compressive strength r... more In the present study, an unified method of HPC mix design was proposed for compressive strength range of 50-60MPa. Puntke test was conducted to determine the optimized combination of Ordinary Portland Cement (OPC) and microsilica (MS). Dry packing test was performed to determine the most dense aggregate combination of different size classes. The results of cementitious materials and aggregates optimization were integrate and imported for the HPC mix design. The volume of surplus paste content was optimized by considering 10%, 15% and 20% additional paste and w/cm ratio of 0.34 and 0.36 in flow table test. Compressive strength and water penetration depth of different HPC mixes were used to substantiate the selection of optimized HPC mix. The Puntke test results indicated an optimized binary blend of 80% OPC and 20% of MS in total cementitious materials. The packing density of three sizes class aggregate blending was found to be 0.900. The mix with 15% surplus paste and 0.34 w/cm was considered as optimized HPC mix based on the recorded flow diameter of 550 mm, compressive strength of 59.15 MPa and least water penetration depth of 6.21mm.

In this experiment the study of influence of polymer in reinforced High Performance Concrete (HPC... more In this experiment the study of influence of polymer in reinforced High Performance Concrete (HPC) beams was done. The polymer being used was Styrene Butadiene Rubber (SBR) Latex The specimen being used here is a rectangular beam section of 2100mm span with 200mm wide and 300mm deep. The beam was tested after 28 days of curing and was subjected to a two-point loading under the loading frame. The parameters studied were load deflection curve, post cracking strength, ductility factor and strength gain factor. The Post Cracking Strength for HPC was 0.0958 kN/mm 2 and for MHPC was 0.1063 kN/mm 2 .The relative ductility factor 1.38. The strength gain factor was 14.715.

This paper presents an experimental study on the effect of presoaked lightweight aggregates (LWAs... more This paper presents an experimental study on the effect of presoaked lightweight aggregates (LWAs) for internal curing on water permeability, water absorption and resistance of concrete to chloride-ion penetration in comparison with those of a control concrete and a concrete with shrinkage reducing admixture (SRA) of similar water/cement ratios (w/c). In general, the concretes with LWA particles had initial water absorption, sorptivity and water permeability similar to or lower than those of the control concrete and the concrete with SRA. The charges passed, chloride migration coefficient and chloride diffusion coefficient of such concretes were in the same order as those of the control concrete and the concrete with SRA. However, the incorporation of the LWAs for internal curing reduced unit weight, compressive strength and elastic modulus of the concrete. Comparing the LWAs of different sizes for internal curing, finer particles were more efficient in reducing the shrinkage and generally resulted in less reduction in the unit weight, compressive strength, and elastic modulus. However, the increase in the more porous crushed LW particles in concrete seems to increase the penetration of chloride ions in the concrete. The concrete with SRA had initial water absorption, sorptivity, water permeability and resistance to chloride ion penetration comparable with those of the control concrete. The use of SRA in concrete does not affect the elastic modulus of the concrete, except for a minor influence on the compressive strength of the concrete.

India is a subtropical country, which receives good amount of rain each year. Due to sudden and m... more India is a subtropical country, which receives good amount of rain each year. Due to sudden and massive urbanization, the availability and supply of water for domestic purpose has introduced new challenges in urban water supply. Rainwater harvesting is a sustainable and reliable approach to manage the water in urban areas. In the recent years, rainwater harvesting is as statutory mandate during construction approval. Pervious concrete is a application oriented special concrete product, which has been effectively used to manage the surface run off in the shoulder, parking lane and other highway applications. In the present experimental study, efforts are made to use the pervious concrete as filtration medium for rainwater harvesting. The mechanical properties and permeability of pervious concrete are studied. A filtration medium model has prepared to study the permeability.

In the present study, an unified method of HPC mix design was proposed for compressive strength r... more In the present study, an unified method of HPC mix design was proposed for compressive strength range of 50-60MPa. Puntke test was conducted to determine the optimized combination of Ordinary Portland Cement (OPC) and microsilica (MS). Dry packing test was performed to determine the most dense aggregate combination of different size classes. The results of cementitious materials and aggregates optimization were integrate and imported for the HPC mix design. The volume of surplus paste content was optimized by considering 10%, 15% and 20% additional paste and w/cm ratio of 0.34 and 0.36 in flow table test. Compressive strength and water penetration depth of different HPC mixes were used to substantiate the selection of optimized HPC mix. The Puntke test results indicated an optimized binary blend of 80% OPC and 20% of MS in total cementitious materials. The packing density of three sizes class aggregate blending was found to be 0.900. The mix with 15% surplus paste and 0.34 w/cm was considered as optimized HPC mix based on the recorded flow diameter of 550 mm, compressive strength of 59.15 MPa and least water penetration depth of 6.21mm.

Our paper documents the effects of using steel fibres in latex modified concrete. The study was c... more Our paper documents the effects of using steel fibres in latex modified concrete. The study was carried out to record the different physical and mechanical properties of steel fibre reinforced latex modified concrete. Latex modified concrete is nothing but, conventional concrete made by replacing part of mixing water with latex. Polymer as an admixture can improve properties like higher strength and lower water permeability than the conventional concrete. Since, concrete is weak in tension, steel fibres have been added to concrete, to improve its characteristics in tension. The polymer concrete specimens with and without fibers were cast and tested to watch the improvement of certain mechanical and physical properties like compressive strengths, tensile strengths, and workability. Styrene Butadiene Rubber Latex polymer and hooked end steel fibres have been used for our study. 5% of SBR Latex and 0.5% of steel fibres have been used. The hardened properties of concrete were tested at 7 th and 28 th days. It was found that the given fibre dosage enhanced the early compressive strength of concrete but reduced the 28 days compressive strength. Steel fibers increase the tensile strength of concrete.

India is a subtropical country, which receives good amount of rain each year. Due to sudden and m... more India is a subtropical country, which receives good amount of rain each year. Due to sudden and massive urbanization, the availability and supply of water for domestic purpose has introduced new challenges in urban water supply. Rainwater harvesting is a sustainable and reliable approach to manage the water in urban areas. In the recent years, rainwater harvesting is as statutory mandate during construction approval. Pervious concrete is a application oriented special concrete product, which has been effectively used to manage the surface run off in the shoulder, parking lane and other highway applications. In the present experimental study, efforts are made to use the pervious concrete as filtration medium for rainwater harvesting. The mechanical properties and permeability of pervious concrete are studied. A filtration medium model has prepared to study the permeability.