Abstract: Large amounts of discards are generated from soil-cutting of slope in replacing expansive soil with cement-modified soil in treatment projects for expansive soil slope. Directly abandoning these discards will lead to waste and also will occupy land. To recycle such discards, we collected samples of moderately expansive modified soil (cement content 6%) and weakly expansive modified soil (cement content 3%) discarded from the filling site of the middle route of South-to-North Water Transfer Project. We further investigated the feasibility of reusing modified soil discards as fillers by testing their compactness, strength, expansion, shrinkage, and permeability features. Results demonstrated that the modified soil discards meet the resuirements of fillers in terms of expansion, physical characteristics, strength and deformation properties except from larger compaction function, thus could be reused as modified fillers.

Key words: middle route of South-to-North Water Transfer Project, cement modified soil, expansive soil, discards from soil cutting of slope, secondary utilization