Mechanical Behavior of Structural Light Weight Concrete Using Low-Strength Clay Bricks Aggregates

Abstract

This research is an experimental study on the fresh-state properties as well as the mechanical behavior of structural lightweight concrete (SLWCs) that made from recycled low-strength clay bricks (RLSCB). The test program includes testing ten mixtures of SLWCs with a target compressive strength of (35 – 40 MPa) and a target air density less than 1900 kg/m3 in addition, three mixtures of normal weight concrete (NWCs) of target compressive strength equal to 37.5 MPa were used for comparison purposes. For each mix of the fresh-status measurements, including slump, density, the air content and the temperature, a number were carried out. Furthermore, the mechanical performance for both SLWCs and NWCs under compressive, flexural and tensile stresses were conducted. The results show that structural lightweight concrete could be produced using recycled low-strength bricks as coarse aggregates with a reduction in dry density equal to 22%. Moreover, the reported results indicate that the compressive strength, splitting tensile strength, modulus of rupture and elastic modulus of elasticity of SLWCs were lower those for NWCs by about 5%, 14.5%, 16.5% and 17.4%, respectively. Finally, correlations between compressive behavior and flexural behavior; compressive behavior and tensile performance; flexural behavior and tensile performance for SLWCs are proposed in this study.