水泥改性土换填处理膨胀土边坡施工时,需要超填形成台阶状边坡再按照一定坡比削坡成型,由此,将产生大量的水泥改性土削坡料,如果直接废弃,既会造成浪费又会大量占地。为解决水泥改性土削坡弃料的再利用的问题,在南水北调中线工程水泥改性土填筑施工现场,分别对中膨胀改性土料(水泥掺量6%)和弱膨胀土改性土料(水泥掺量3%)的削坡弃料进行取样试验,通过测试改性土弃料的压实、强度、胀缩和渗透特性等,分析改性土弃料再次作为填料的可能性。研究结果表明,水泥改性土削坡弃料膨胀性、物理特性、强度和变形性能均满足填筑土料要求,仅需要更大的压实功即能达到预期的效果,水泥改性土削坡弃料可以作为改性填料使用。

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.