BEHAVIOR OF EXPANDED POLYSTYRENE BLOCKS

An innovative construction material, expanded polystyrene blocks (EPS blocks), has been introduced in geotechnical engineering in recent years. Because of its extremely light weight and ease in handling, it provides an alternative to conventional backfill, embankment earth materials, and lightweight fill. It is anticipated that the use of EPS blocks in the construction industry may result in substantial cost savings. New applications of EPS blocks as structural elements are expected to emerge as engineers learn more about this material. A series of laboratory tests were conducted to determine the mechanical properties of EPS blocks. Included are the results of undrained triaxial tests with volume change measurements for the determination of a constitutive relationship, a repeated loading test, punching shear tests, and a long-term creep test. The test results show several distinctive material characteristics, including a bilinear stress-strain relationship and negative Poisson's ratio that are not common in conventional construction materials. The results of this study can readily be incorporated in detailed analyses of various geotechnical engineering structures constructed with EPS blocks.