Waste disposal has become a serious problem because of lack of land-fill and it should be solved urgently. It is therefore desirable to develop an effective method of geotechnical treatment to use the waste materials. The waste expanded polystyrene (EPS), which is widely obtained in Japan, may be utilized as a material for lightening by mixing with soil. The aim of this study is to investigate the compression and direct shear properties of a mixture of sand and heat compressed and crushed EPS (HCCE) for possible use as a light weight fill material. The test results showed that the HCCE material was effective to lighten the self-weight of soil and also to increase the shear strength of geomaterial. In addition, the sand mixed with the HCCE material was found to be a useful fill material on soft ground based on the results of the slope stability analysis.
Waste disposal increases year by year, and has become a significant social problem. In our country with the narrow land, to limit the space of waste disposal has become difficult, and therefore, weight reduction, resource recovery and the reuse of waste materials becomes an important subject requiring urgent solution. In such social background, an effective utilization of the waste expanded polystyrene (EPS), which is widely obtained in Japan, is considered as a challenge for the waste problem from the geotechnical viewpoint. The aim of work presented in this paper is to investigate the compression and direct shear properties of a combined sand and heat compressed and crushed EPS (HCCE) mixture for possible use as a lightweight fill material. It is important to point out that the HCCE material is chemically stable. Five kinds of light-weight soils including various contents of the HCCE material were prepared.