Structural grade concrete containing expanded polystyrene beads with different particle distributions of normal weight aggregate

Abstract

Expanded polystyrene (EPS) it is a material with wide range usage because has some valuable properties like low-density, low-thermal transmission coefficient, negligible absorption capacity, etc.. For concrete, EPS beads may be incorporated in the structure of concrete as light aggregate, partially or fully replacing the normal weight aggregate. The study intends to develop concrete of structural grade containing polystyrene aggregate and to investigate the influence of some different particle distributions of aggregate on compressive strength of concrete which contains expanded polystyrene beads in various percentages of aggregate replacement. The aggregate particles between 2 and 8 mm were partially replaced with EPS beads. The replacement volumes of natural aggregate with EPS beads were 15, 25 and 35%. For all mixes, the cement content was kept constant and the design water to cement ratio was selected to moderate and low-moderate values. For all mixes the maximum size of aggregate was maintained constant equal to 16 mm. In this study, two particle distributions of aggregate were considered, continuous particle distributions, rich in coarse (CA) or fine (FA) aggregate, respectively. The strength of concrete in some extent is influenced by the particle distribution of aggregate when natural weight aggregate particles of a certain size is partially replaced with polystyrene EPS beads of the approximately same size. For the studied mixes, for each considered water to cement ratio, the influence of particles distribution of aggregate on compressive strength increases with the percentage of replacement with EPS beads. It has been found that hardened concrete with EPS beads provide enough final strength in order to be used for some structural applications and also for developed mixes, the segregation of polystyrene beads toward the top surface is poor and theirs distribution into the mass concrete is uniform..