为了寻求“不进行地基处理的软基处理方法”，通过减轻路堤填土重量来提高软基的稳定性和减少沉降。研究了聚苯乙烯泡沫塑料轻质填土SLS的轻质、高强、变形间的相关关系，找出有工程应用前景的配方。通过和常规路堤填土的比较，对SLS的工程性质进行了评价。特别从环保角度出发，探讨了利用废泡沫塑料碎粒的可能性。 In order to find “a soft foundation treatment method without foundation treatment”, the stability of soft foundation and the reduction of settlement are improved by reducing the weight of embankment filling. The correlation between light weight, high strength and deformation of polystyrene foam lightweight soil SLS was studied, and the formulation of engineering application prospect was found out. By comparing with conventional embankment fillings, the engineering properties of SLS were evaluated. In particular, from the environmental point of view, explored the possibility of using waste foam granules.