Properties of Lightweight Concrete Using Expanded Polystyrene as Aggregate

Abstract

When large structures are built on the soft ground such as paddy field, the demand for lightweight concrete will be high. However, issues related to quality control of lightweight aggregates, decline in the tensile strength of lightweight concrete, the economic problems, and so on, have been inhibiting the promotion of its development. There are some conventional methods of construction to cast the large size of expanded polystyrene (EPS) blocks near the surface of soft ground. But there is concern that the EPS block will float up by liquefaction in case of earthquake. In this study, the strength properties of lightweight concrete which uses EPS waste as fine aggregate have been investigated. The above-mentioned concern could be wiped out by mixing EPS as aggregate in concrete aggregate. This EPS aggregate is manufactured product, but there is extremely little number of the factories. The volume of this aggregate was reduced by being irradiated the extreme infrared radiation to utilize the stockyards effectively. This aggregate is ecological because its origin is the industrial waste of EPS. That the absorption of water is zero is one of the merits as the aggregate for concrete. The author has obtained experimentally the mix proportions for the concrete that have the compressive strength enough to be used as structural material. As the results, the treatment of EPS using extreme infrared radiation was found to be effective in improving the strength of EPS concrete.