Indian Concrete Journal

Effects of coal bottom ash on the standard consistency and setting time of binary binders Kiruthiga P., Niragi Dave, Ramesh Guduru, Vishal Asnani

In this paper, bottom ash’s capacity to be recycled is demonstrated at the submicron level. Due to its predominance in sand-sized particles, coal bottom ash has not yet been properly utilized in the building sector. To study the impact of standard consistency, initial and final setting times of the binary paste, pulverized coal bottom ash (PBA) was substituted for ordinary Portland cement (OPC) as binary binders. Experiments show that pulverized bottom ash with a large surface area has a stronger impact on the replacement bottom ash’s standard consistency. Due to the large surface area of pulverized bottom ash, water consumption increases PBA percentage levels inside the paste rise. The standard consistency and setting time of PBA cement paste at various replacement levels, ranging from 0 % to 30 % of PBA as a cement substitute. Vicat’s apparatus is used to ascertain the standard consistency and setting time, and it is discovered that the consistency of PBA cement paste grew as the PBA concentration increased and was in the range of 32 % to 35.5 %. When compared to OPC cement paste, PBA cement paste has a greater degree of consistency. The PBA content has been discovered to affect the PBA binder’s setting time, which was found to range between 85 to 160 and 20 to 275 minutes. When the prices for OPC and PBA binder were compared, it was discovered that the price of PBA was much less than that of OPC binder.

Mechanical investigation of high strength sustainable ternary geopolymer concrete Lokesh Choudhary, Vaishali Sahu, Archanaa Dongre

With the objective of making today’s concreting practices more sustainable, the current study compares ternary geopolymer concrete made with a mix of fly ash, ground granulated blast furnace slag, and metakaolin, along with natural and foundry sand, in two different types of specimens. Several cylindrical, beam, and reinforced slab specimens of M35, M45, and M60 grade geopolymer concrete were cast and tested for compressive strength, flexural strength, split tensile strength, cyclic bending strength, and impact strength during the study. The study’s findings demonstrate that ternary geopolymer concrete has higher mechanical strength (compressive, tensile, and fatigue) than traditional ordinary Portland cement (OPC) based concrete. Further, while natural sand specimens were observed performing better than foundry sand specimens, the findings reported for foundry sand samples were found to be within the prescribed strength criteria provided by IS code regulations. The study’s findings also provide unique correlations between split tensile strength and characteristic compressive strength of ternary geopolymer concrete that can be reckoned by practicing engineers for ready use. The study’s findings encourage the use of foundry sand as a substitute for scarce natural sand. Adding to financial aspect, the study also presents a cost comparison promoting more economic usage of high strength ternary geopolymer concrete over lower grades of concrete.

Effect of submicron ceramic waste powder on the standard consistency and setting properties of binary binders Niragi Dave, Kiruthiga P.

The most pressing problem facing humanity today is waste, and finding a solution is a top priority. Use of waste is now seen as a viable alternative to landfilling. Many papers have been written on the topic of recycling in the building industry, with much of the research focusing on repurposing old structures or incorporating waste materials into concrete to create novel varieties of the material. Putting waste to good use is not just a cost-effective solution to the disposal problem, but also an attractive one. The ever-increasing quantity of ceramic waste has caught the interest of many in discovering eco-friendly uses for it in building materials. In this study, we present a ceramic waste that was pulverized at 600 rpm to convert it into submicron level. Pulverized ceramic waste was used to supplement cement up to 30 %. The standard consistency and setting time of pulverized ceramic waste powder (PCWP) used in cement paste at various replacement levels, ranging from 0 % to 30 % as a cement substitute. Vicats apparatus is used to determine the standard consistency and setting time, and it is observed that the consistency of PCWP increased with the increasing % level of PCWP. When compared to OPC cement paste, PCWP cement paste has a greater degree of consistency. The PCWP content has been revealed the effect of PCWP binder’s setting time, which was found to range between 90 to 138 and 200 to 245 minutes. TGA was performed to determine the loss of ignition and it was 3.5 %. The microstructure of PCWP and OPC were studied and particle size was compared with the help of SEM. When the prices for OPC and PCWP binder were compared, it was discovered that the price of PCWP was much less than that of OPC binder.

Effects of coconut fiber on mechanical properties of pervious concrete incorporating recycled concrete aggregates Shuddhashil Ghosh, Shubham Bansal, Lokesh Choudhary, Vaishali Sahu

Pervious concrete is acknowledged as an environmentally friendly material due to its capacity to enable water passage and efficiently handle stormwater runoff. This current study delves into the influence of incorporating coconut fiber into pervious concrete pavement, specifically exploring the alterations in mechanical properties through the reinforcement with coconut fiber. The experimentation encompassed the introduction of coconut fiber (0-1 % of the cement’s weight) into the mix, along with varying proportions of recycled concrete aggregate (RCA) at 25, 50, 75, and 100 %. The assessment focused on evaluating the resulting pervious concrete’s compressive strength, flexural strength, and permeability. The study’s outcomes underscore several noteworthy findings. Firstly, the incorporation of coconut fiber was observed to enhance the mechanical properties, particularly the compressive strength and flexural strength of pervious concrete, showcasing improvements with a 1 % fiber content compared to 0 %. This suggests that an optimal fiber content can augment load-bearing capacity and crack resistance. Furthermore, the introduction of coconut fiber did not compromise the permeability of pervious concrete, maintaining it within acceptable limits for effective stormwater management. Additionally, a comprehensive examination of the impact of aggregate size revealed a more pronounced effect on compressive strength in mixes containing RCA. In conclusion, these findings enhance our comprehension of the mechanical properties of pervious concrete and present a sustainable avenue for enhancing its performance. The research opens avenues for the development of environmentally friendly and resilient pavement systems, effectively managing stormwater runoff in urban areas while preserving structural integrity

Effect of pulverized ceramic waste powder as a partial cement replacement in cement paste and mortar application Niragi Dave, Kiruthiga P., Vishal Asnani

The current global challenge of waste management necessitates the exploration of viable alternatives. At present, the utilization of garbage is regarded as a viable alternative to landfilling. The objective of this study is to generate unitary and binary cement binders and mortars by incorporating ordinary Portland cement (OPC) with supplementary cementitious materials (SCM_s), including pulverized ceramic waste powder at replacement levels of 2.5 and 30 %. The water-to-binder ratio was maintained at a constant value of 0.45 for both binders and mortars. A series of experiments were conducted on binary binders to assess the compressive strength and microstructural study at 28 and 90 days. Compressive strength experiments were conducted on binary cement mortar mixes with ratios of 1:3 and 1:4 at 28 and 90 days. The objective of this study was to formulate a novel binary binder with the potential to decrease reliance on cement. The various combinations of binary binders shown superior progress in compressive strength compared to the control binder. The incorporation of pulverized ceramic waste powder mortars resulted in enhanced compressive strength and reduced permeability, surpassing the performance of binary mortars. The performance of quaternary binders and mortars demonstrates satisfactory suitability for industrial applications.