Study of a New Plaster Composite Based on Dune Sand and Expanded Polystyrene as Aggregates

Introduction: This study aims to highlight the physicomechanical properties of a new lightweight construction material which is composed of plaster as a binder and dune sand and Expanded Polystyrene Beads (EPS) as aggregates. Methods: For this purpose, different mixtures were designed with different percentages and particle sizes of EPS aggregates in order to test the porosity, the density and the thermo-mechanical properties of the studied composite. Furthermore, Electron Microscopy (EM) visualisation and SEM analysis were used for the study of the structure and the interface “paste-aggregates”. Results and Conclusion: The obtained results showed that the progressive incorporation of an increasing percentage of PSE decreases the density of the plaster composite and consequently improves its thermal properties. As expected, the mechanical strength decreases with the increase of the EPS content, but relatively good mechanical strength can be obtained with low quantities of EPS. Concerning the material structure, it should be noted that the composite appears more or less homogeneous and the EPS beads adhere well to the plaster matrix.