Expanded Polystyrene (Expanded Polystyrene referred to as EPS) is a light-weight polymer. It uses polystyrene resin to add a foaming agent, and at the same time it is heated to soften it to generate gas and form a rigid closed-cell structure of foam.
The processing method can be divided into the mode method and the extrusion method according to the different foaming methods. This uniformly closed cavity structure makes the EPS have the characteristics of low water absorption, good heat preservation, light weight and high mechanical strength. Northern Europe began to use EPS for civil engineering in the late 1960s. In 1971, the Norwegian National Road Research Laboratory (NRRL) used EPS for the first time in the FLOM bridge approach reconstruction project to replace the 1m thick ordinary filler, and successfully controlled the uneven settlement of the bridge head section. Due to the good overall economy and quality effects, the consumption increased rapidly in the 1980s. Countries such as Sweden, Japan, the Netherlands and other countries have already used EPS in highway projects. In 1995, my country used EPS for the first time in the embankment of the Wangtong Overpass Bridge of Hangzhou-Ningbo Expressway.