Are the mechanical properties of recycled-content expanded polystyrene (EPS) comparable to non-recycled EPS geofoam?

摘要

Non-recycled expanded polystyrene (EPS) geofoam has been widely used in geotechnical engineering applications such as lightweight fill in embankments over soft ground and in slope stabilization and repair. However, recycled-content EPS blocks are not widely used because mechanical property test results, which can ensure properly designed and safe infrastructure systems, are currently unavailable. This paper presents the results of unconfined compression, flexure, and creep tests performed on recycled-content EPS with various percentages of recycled polystyrene. The mechanical properties of recycled-content EPS obtained from these tests are compared with the minimum property requirements for non-recycled content EPS included in ASTM standard D6817. The laboratory test results indicate that EPS geofoam consisting of recycled-content EPS can be produced to meet current ASTM D6817 minimum compressive resistance and flexural strength requirements. A summary of the influence of the addition of various percentages of recycled polystyrene on the mechanical properties of EPS geofoam is provided to assist manufacturers of EPS-block geofoam produce recycled-content EPS geofoam with the desired engineering properties. It is anticipated that the availability of recycled-content EPS mechanical test results will extend the use of recycled-content EPS geofoam to geotechnical applications, which will contribute to decreasing the volume of polystyrene that ends up in landfills and will contribute to more sustainable infrastructure systems.