Green non-load bearing concrete blocks incorporating industrial wastes

Abstract

In this study, use of glass powder and marble powder as partial replacement of cement in various proportions (5%, 10%, and 15% by weight) in manufacturing of non-load bearing hollow concrete blocks is investigated. The manufactured blocks were evaluated for various characteristics as per ASTM C140/C140M, such as compressive strength, dry density and water absorption. Marble powder is obtained during sawing, cutting, shaping and polishing of marble, and it is normally rendered as solid waste. A huge quantity of discarded glass is dumped in landfills, world over. The mean dry densities of marble powder and glass powder used in this work are 2656.2 kg/m 3 and 2547.4 kg/m 3 , respectively, making them lighter than ordinary cement. The optimum value is found to be 10% replacement of cement (by mass) by the waste materials. It is found that the compressive strength increases by 40% and 18%, dry density decreases by 4% and 5% and water absorption increases by 28% and 36%, if 10% cement is replaced by marble powder and glass powder, respectively. It can be concluded from the results that the non-load bearing hollow concrete blocks with improved compressive strength and light weight can be manufactured by using glass powder and marble powder. Recycling of solid wastes like marble powder and glass powder in concrete is advantageous: It will not only address the waste management issues, but will also result in saving the quantity of cement in concrete, which itself is environmentally hazardous material.

Evaluation of Concrete with Partial Replacement of Cement by Waste Marble Powder

“…This research is the continuation of the works of Munir et al (2018) [14] and Ahmed et al (2020) [15], involving recycling of WMP in clayey bricks and hollow concrete blocks, respectively. WMP is abundantly produced in Pakistan and is dumped in earth fills: This necessitates its proper recycling.…”

“…Up to 10% replacement, the effect of higher fineness of WMP particles seems dominant, which increases the compactness and density of the mix, Also, water to cement ratio is lesser owing to higher absorption of WMP particles, which increases strength and reduces slump and voids [21,22]. The dense microstructure of concrete containing 10% WMP is shown in Figure 7 [15]. According to Aïtcin, in a dense cement paste, the water available for hydration is low.…”

“…The hydrates formed on the surface of a cement particle are left with little space to fully grow: This in turn leaves their centers as un-hydrated, which act as hard inclusions imparting high compressive strength [23]. The dense cement matrix containing 10% WMP is shown in Figure 7 [15].…”

“…Ahmed et al (2020) evaluated the effect of partial replacement of cement by WMP in concrete hollow blocks. They have reported an increase in compressive strength up to 10% replacement: The increase is attributed to the angular shape of the waste marble particle, which ensures mechanical bond with the surrounding cement matrix [15].…”