Performance Evaluation of Problematic Subgrade by adding Reclaimed Masonry and Cement: A Sustainable Solution for Construction Waste

Abstract

Natural disasters and human demolition generate huge quantity of construction and demolition waste (CDW), posing an environmental threat globally. Reclaimed brick masonry makes up a noteworthy portion of CDW, totaling approximately 31%, even exceeding concrete waste. Hence, this study suggests using reclaimed brick masonry to enhance both the micro and macro properties of clayey soil. Extensive laboratory experimenting was took out to assess the performance of reclaimed brick powder (BP) along with 5% cement content. The cement was used to generate chemical bonds with BP and soil grains. Micro testing like XRF, XRD, EDAX, and SEM analyses confirmed the formation of CSH and CAH compounds which strengthened soil structure and enhanced its brittleness. However, after 10% BP, the addition of coarser grains converted the soil structure from dense to porous. Macro properties assessment confirmed that 10% BP with 5% cement content is an optimum combination for selected soil. The addition of BP reduces the required amount of cement for soil stabilization making it more eco-friendly solution. The addition of the optimum combination decreased the wL, IP, FSI, wopt, and Cc and increased the dmax, qu, CBR value, and y significantly. It is also confirmed by the specimen’s failure morphology analysis that BP with cement in clayey soil curtailed cement generated brittleness and enhanced ductility.