Behaviour of a Foam Mixture as a Lightweight Construction Material

Building on weak soils is very challenging in engineering projects, especially highway and railway projects. To overcome these problems, especially in the construction of embankments and abutments, it is necessary to reduce the settlement of soil and increase the bearing capacity. This paper investigates the characteristics of expanded polystyrene (EPS) foam beads mixture as a lightweight construction material. EPS foam is characterized as a lightweight, economic and environmentally friendly material. Samples of different mixtures were prepared using EPS foam beads with sand, cement and water at different ratios. A series of rigorous tests were carried out to evaluate density, shear strength parameter, compressibility, and crushing strength of the prepared mixtures. The mixture of foam beads and sand was mixed in ratios 1:1, 1.5:1 and 1:2 by volume and mixed with cement content of 7%, 8%, 9% and 10% of sand weight using the optimum water content. From the results it was found that the best ratio between sand and foam beads by volume was 1:1, and high cement ratio of 10% formed lightweight mass with acceptable crushing strength, CBR and compressibility characteristics. The results proved that, the characteristics of the mixture are linearly proportional with cement content and curing time. Practically, the mixture can be used as a subgrade material to overcome the problems of weak soils especially in highway construction.