The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform
Brind Kumar - One of the best experts on this subject based on the ideXlab platform.
-
Effects of rice straw ash and micro silica on mechanical properties of pavement Quality Concrete
Journal of building engineering, 2019Co-Authors: Arunabh Pandey, Brind KumarAbstract:Abstract This research deals with improvement in the mechanical strength of Pavement Quality Concrete (PQC) when admixed with Rice Straw Ash (RSA) and Microsilica (MS). Nine mixes were prepared by partially substituting Ordinary Portland Cement (OPC) by MS (2.5%, 5%, 7.5%, and 10%), RSA (10%) and RSA-MS composite (5%–5%, 5%–7.5%, 10%–5% and 10%–7.5%). Maximum improvement was found when OPC was partially replaced by 7.5% in the case of MS and 5%–7.5% in case of RSA-MS composite. All the mix showed increased strength, w.r.t the control mix. X-Ray powder diffraction (XRD) and Scanning Electron Microscope (SEM) techniques were employed for characterization of the selected samples. Power regression equations were established to predict split tensile and flexural strength from compressive strength. They were compared with universally accepted equations and were found to be more accurate for RSA and MS admixed Concrete. Mix R1M3 (5% RSA, 7.5% MS) is recommended based on the findings.
-
Evaluation of water absorption and chloride ion penetration of rice straw ash and microsilica admixed pavement Quality Concrete
Heliyon, 2019Co-Authors: Arunabh Pandey, Brind KumarAbstract:Abstract The effects of rice straw ash (RSA) and microsilica (MS) on durability properties (water absorption and chloride ion penetration) of M40 grade Pavement Quality Concrete (PQC) were studied. Ten Concrete samples were prepared by partially substituting cement with RSA and MS in various proportions. A significant reduction was observed in the water absorption and chloride ion penetration in Concrete samples with an increase in the curing age as well as with an increase in the proportion of MS and RSA. The maximum reduction in water absorption and chloride ion penetration was observed in R2M3 (10% RSA and 7.5% MS) as compared to control Concrete (R0). The analytical relationships were developed between the above-mentioned parameters and curing age of Concrete. A linear equation was established between the initial and secondary rate of water absorption of Concrete and also between the chloride ion penetration of Concrete at 10–20 mm and 25–35 mm depth. Both these equations were applicable to all the Concrete samples of this study. Predictive charts were generated between the above-mentioned parameters and days of curing in water.
-
assessment of water absorption and chloride ion penetration of pavement Quality Concrete admixed with wollastonite and microsilica
Construction and Building Materials, 2009Co-Authors: G D Ransinchung, Brind Kumar, Veerendra KumarAbstract:Abstract Wollastonite with or without microsilica was evaluated as a new material for partial replacement of cement in M40 grade pavement Quality Concrete. Wollastonite is abundantly available in the Udaipur belt of Rajasthan state in the Indian union as a low cost material. Its physical and chemical properties were analyzed. This particular wollastonite consists of 45.6% of CaO and 48% of SiO 2 , mainly in amorphous form and has an average specific surface area of 842.7 m 2 /kg. Five finalized Concrete mix proportions including the control mix were investigated for saturated water absorption, rate of water absorption, coefficient of water absorption and chloride ion penetration. Test results indicate that up to 15% of wollastonite and 7.5% microsilica can be advantageously admixed with cement to significantly improve the water tightness of Concrete due to reduction in pore space and refinement of microstructure. Mathematical relationships existing between these parameters were studied and predictive graphs were developed.
Abhishek Jindal - One of the best experts on this subject based on the ideXlab platform.
-
Behavioral study of self-compacting Concrete with wollastonite microfiber as part replacement of sand for pavement Quality Concrete (PQC)
International journal of transportation science and technology, 2019Co-Authors: Abhishek Jindal, Praveen KumarAbstract:Abstract The fact that self-compacting Concrete (SCC) does not require any supplementary compaction to fill in every nook and corner of the structure without compromising with strength and durability makes it much more futuristic and desirable over conventional Concrete. Present study highlights the behavioural changes in SCC for PQC applications at macro and micro levels with the incorporations of wollastonite micro-fiber; proposed to be used for restoration of deteriorated pavement Quality Concrete slab. Wollastonite micro-fiber was incorporated as part replacement of fine aggregates in proportions of 10–50% with an offset of 10%. Different properties of SCC mixes such as flow-ability, segregation resistance and filling ability were investigated in fresh state while mechanical properties including compressive strength, flexural strength and hardened density were studied in hardened states. The SCC mixes were also investigated for estimating effect of incorporating wollastonite micro-fiber in hydrated states of cement mortar. Inclusions of wollastonite micro-fiber in SCC enhanced the cohesiveness of the mix thereby improving the density and reducing its water absorption. SCC mixes with wollastonite micro-fiber showed higher flexural and comparable compressive strength parameters than those of conventional SCC mix. SCC mix with 30% wollastonite micro-fiber as a replacement of fine aggregates provides similar strength and better repair prospects as compared to conventional SCC or normal Concrete mix.
-
Behavioural study of pavement Quality Concrete containing construction, industrial and agricultural wastes
International journal of pavement research and technology, 2018Co-Authors: Abhishek JindalAbstract:Abstract This study proposes the use of industrial and agricultural wastes as mineral admixtures for enhancing the mechanical and durability aspects of Concrete containing recycled Concrete aggregates derived from Concrete waste. The study was carried out by testing specimens prepared from Concrete mixes with and without recycled Concrete aggregates and three different mineral admixtures viz: fly ash (an industrial waste), rice husk ash and bagasse ash (agricultural wastes) for their compressive strength, flexural strength, split tensile strength, workability, chloride ion concentrations, carbonation, sorptivity and abrasion resistance in order to assess the variations and improvements. It was observed that Concrete mix upon incorporating mineral admixtures showed significant improvement in both mechanical and durability properties when compared to Concrete mix with recycled Concrete aggregates alone. Fly ash admixed mixes showed a gain of 15% and 24% for compressive and flexural strength parameters, while the gain for rice husk ash mix and bagasse ash mixes was observed to be 12% and 25%, 13% and 20% respectively when compared to recycled aggregate Concrete mix without mineral admixtures. Improvements in durability aspects were observed by incorporating mineral admixtures supported by lower parameters for water absorption, sorptivity coefficients and chloride ion concentrations and increased hydration products as concluded from scanning electron microscopic investigations.
-
Study of pavement Quality Concrete mix incorporating beneficiated recycled Concrete aggregates
Road Materials and Pavement Design, 2016Co-Authors: Abhishek Jindal, Praveen KumarAbstract:The present study is an effort to investigate the influence of recycled Concrete aggregates (RCAs) on the mechanical and durability properties of pavement Quality Concrete under different moisture states. Four moisture states, namely as received state (AD), saturated surface dry state (SSD), fully saturated state (FSD) and oven dried state (OD) of aggregates were considered in this study. RCAs manufactured upon processing of demolished Concrete wastes were subjected to chemical beneficiation (using H2SO4) followed by abrasion prior to their incorporation in an experimental programme. In all, 24 mixes incorporating RCAs at different proportions of 10–50% with an interval of 10% for M-40 grade of Concrete were prepared to investigate the properties of hardened Concrete, such as compressive strength, flexural strength, water absorptions, chloride ion concentrations, sorptivity, abrasion, etc. Scanning electron microscopic analysis on thin samples collected from all 24 mixes was carried out in order to unders...
-
DURABILITY STUDIES OF PQC MIX INCORPORATING RECYCLED Concrete AGGREGATE AND MINERAL ADMIXTURES
Proceedings of International Structural Engineering and Construction, 2016Co-Authors: Abhishek JindalAbstract:Concrete as known globally is the most widely used construction material in all type of construction works. Recycled Concrete aggregates have been eyed as a viable option for part replacement of natural coarse aggregates for Concrete production by researchers for quite some time. However, their tendency to bring down the property parameters of new Concrete makes it very important to investigate the extent of variation in durability properties of fresh Concrete incorporating recycled Concrete aggregates. Mineral admixtures are believed to improve the durability and mechanical aspects of Concretes. This study makes an effort to understand the effects of incorporating recycled Concrete aggregates and different mineral admixtures on durability aspects of pavement Quality Concrete mixes. In order to investigate the same, recycled Concrete aggregates were used along with mineral admixtures in different proportions to study the variation in properties. Concrete mixes prepared with natural aggregates, recycled Concrete aggregates and mixes containing recycled Concrete aggregates and mineral admixtures were prepared and tested for variations in their durability properties. Laboratory investigations revealed that incorporating mineral admixtures does improves the durability aspects of pavement Quality Concrete having recycled Concrete aggregates. Reduction in values for water absorption, sorptivity coefficients and chloride ion concentrations supported better durability aspects for mixes prepared with recycled Concrete aggregates incorporating mineral admixtures.
Veerendra Kumar - One of the best experts on this subject based on the ideXlab platform.
-
assessment of water absorption and chloride ion penetration of pavement Quality Concrete admixed with wollastonite and microsilica
Construction and Building Materials, 2009Co-Authors: G D Ransinchung, Brind Kumar, Veerendra KumarAbstract:Abstract Wollastonite with or without microsilica was evaluated as a new material for partial replacement of cement in M40 grade pavement Quality Concrete. Wollastonite is abundantly available in the Udaipur belt of Rajasthan state in the Indian union as a low cost material. Its physical and chemical properties were analyzed. This particular wollastonite consists of 45.6% of CaO and 48% of SiO 2 , mainly in amorphous form and has an average specific surface area of 842.7 m 2 /kg. Five finalized Concrete mix proportions including the control mix were investigated for saturated water absorption, rate of water absorption, coefficient of water absorption and chloride ion penetration. Test results indicate that up to 15% of wollastonite and 7.5% microsilica can be advantageously admixed with cement to significantly improve the water tightness of Concrete due to reduction in pore space and refinement of microstructure. Mathematical relationships existing between these parameters were studied and predictive graphs were developed.
G D Ransinchung - One of the best experts on this subject based on the ideXlab platform.
-
assessment of water absorption and chloride ion penetration of pavement Quality Concrete admixed with wollastonite and microsilica
Construction and Building Materials, 2009Co-Authors: G D Ransinchung, Brind Kumar, Veerendra KumarAbstract:Abstract Wollastonite with or without microsilica was evaluated as a new material for partial replacement of cement in M40 grade pavement Quality Concrete. Wollastonite is abundantly available in the Udaipur belt of Rajasthan state in the Indian union as a low cost material. Its physical and chemical properties were analyzed. This particular wollastonite consists of 45.6% of CaO and 48% of SiO 2 , mainly in amorphous form and has an average specific surface area of 842.7 m 2 /kg. Five finalized Concrete mix proportions including the control mix were investigated for saturated water absorption, rate of water absorption, coefficient of water absorption and chloride ion penetration. Test results indicate that up to 15% of wollastonite and 7.5% microsilica can be advantageously admixed with cement to significantly improve the water tightness of Concrete due to reduction in pore space and refinement of microstructure. Mathematical relationships existing between these parameters were studied and predictive graphs were developed.
F Von Der Weid - One of the best experts on this subject based on the ideXlab platform.
-
innovative process routes for a high Quality Concrete recycling
Waste Management, 2013Co-Authors: Yannick Ménard, Jean Eric Poirier, Fabrice Bonnaudin, Solène Touzé, Gilles Ruffié, A Lemoign, F Von Der WeidAbstract:Abstract This study presents alternative methods for the processing of Concrete waste. The mechanical stresses needed for the embrittlement of the mortar matrix and further selective crushing of Concrete were generated by either electric impulses or microwaves heating. Tests were carried out on lab-made Concrete samples representative of Concrete waste from Concrete mixer trucks and on Concrete waste collected on a French demolition site. The results obtained so far show that both techniques can be used to weaken Concrete samples and to enhance aggregate selective liberation (that is the production of cement paste-free aggregates) during crushing and grinding. Electric pulses treatment seems to appear more efficient, more robust and less energy consuming (1–3 kW h t−1) than microwave treatment (10–40 kW h t−1) but it can only be applied on samples in water leading to a major drawback for recycling aggregates or cement paste in the cement production process.
