Assessing the Mechanical, Thermal, Transport and Microstructural Properties of Foamed Concrete Reinforced with Biomass Oil Palm Trunk Fiber

Oil palm trunk is one of the main oil palm biomass generated in palm oil plantations with limited use. This study investigates the effect of varying OPTF weight fractions (0%, 2%, 4%, 6%, and 8%) on the properties of foamed concrete (FC) with densities of 750, 1150, and 1550 kg/m3. The study quantitatively assesses the fresh-state, transport, thermal, and mechanical properties of FC, including workability, water absorption, porosity, flexural and compressive strength, ultrasonic pulse velocity (UPV), and thermal conductivity. The results show that the inclusion of 4% OPTF at 750 kg/m3 and 6% OPTF at 1150 and 1550 kg/m3 optimally enhanced the mechanical and thermal properties of FC. Specifically, the flexural strength of FC increased by up to 141% at 1550 kg/m3 with 6% OPTF, and the compressive strength improved by 79% at 1150 kg/m3. Water absorption and porosity decreased with the addition of OPTF, while workability decreased in proportion to the OPTF weight fraction. Ultrasonic pulse velocity (UPV) increased by 12.5% at 750 kg/m3 with 6% OPTF, and thermal conductivity decreased by up to 27.6% at 750 kg/m3 with 6% OPTF. These findings highlight the significant improvements in the mechanical and thermal properties of FC incorporating OPTF.