Flexural behavior of lightweight reinforced concrete beam containing palm oil clinker as aggregates

Abstract

Lightweight concrete (LWC) is an innovative technique for construction purposes. Lightweight concrete can be categorized into three different types which are no-fine concrete, lightweight aggregate concrete and aerated concrete. In this study, an investigation on lightweight concrete was carried out using palm oil clinker (POC) as lightweight aggregates. Two mixes of lightweight concrete were developed, named as POCC100 and POCC50 where each mix utilized 100% and 50% replacement of fine and coarse aggregates. The POC concrete mixture was used in order to cast the structural reinforced concrete beam. The physical and mechanical properties of fine and coarse POC aggregates were investigated in term of sieve analysis, bulk density, specific gravity, fineness modulus and ACV test to confirm the suitability to replace normal fine and coarse aggregates. The fresh and hardened POC concrete was tested and compared to the normal concrete (NC). The hardened state of the concrete was investigated through density test, water absorption, ultrasonic pulse velocity, cube compressive, splitting tensile, flexural tensile, modulus of elasticity and Poisson’s ratio. From density test, POC concrete can be considered as a lightweight concrete since the density of the POC concrete obtained was 1990 kg/m3 which are below than usual normal weight concrete density. The concrete mechanical properties test results on POCC100 and POCC50 show that the concrete compressive strength was only 14.30% and 4% less than the NC, respectively. Flexural beam test were conducted on three different beam specimens, i.e. control beam (NC), POCC100 and POCC50 beams. The tested results of the POC reinforced concrete beam show that the ultimate load of the POCC100 and POCC50 beams was comparable to about 88% and 95% to NC beam, respectively. Finding in this study found out that replacement of POC showed lower value of compressive strength by 13% compared to NC. However, replacement of POC benefits in weight reduction by 15% compared to NC. As a conclusion, POC is considered suitable to replace fine and coarse aggregates in the concrete proportion. In terms of sustainability of solid waste management, the application of the POC in construction will reduce the redundant of by-products resulted from the palm oil industries.