Evaluation of particle size distribution and mechanical properties of mineral waste slag as filling material

Abstract The resource utilization of solid waste in civil engineering is an essential direction of environmental governance. This study systematically investigated the feasibility of mineral waste slag as subgrade filler. The optimal compaction parameters of the waste slag were determined. The effects of different factors on the particle size distribution and mechanical properties of mineral waste slag were evaluated, and the construction parameters of the waste slag were recommended. The results show that when the coarse grain content (CGC) increases from 20% to 80%, the optimal moisture content of the mineral waste slag reduces from 13.03% to 10.50%. The CGC and compactive effort have a greater effect on the particle size distribution and mechanical properties of waste slag. The unconfined compressive strength of the sample reaches a maximum of 0.687 MPa when CGC is 50%. The recommended CGC of waste slag is about 50% in practical engineering, and the moisture content should be strictly controlled.