Development of lightweight building blocks using expanded polystyrene

This study aimed to develop lightweight building blocks using Expanded Polystyrene (EPS) with varying percentages, assess their properties, including density, water absorption, porosity, and compressive strength, and evaluate the unit cost of the blocks. The heat-passing rate of the blocks was also investigated. EPS blocks were produced at the Concrete and Materials Testing Laboratory in the Farm Structure and Environmental Engineering Department, Bangladesh Agricultural University, Mymensingh. Local sand and ordinary Portland cement were utilized, with the EPS bead sizes ranging from 2.36mm to 6.35mm. Five different percentages of EPS beads (0%, 5%, 10%, 15%, and 20%) were selected for each block, and the cement-to-sand ratio was 1:4. A total of 75 EPS blocks were fabricated and cured in water for 28 days. The results showed that the density was highest for 0% EPS blocks (2139.75 kg/m3) and lowest for 20% EPS blocks (1699.08 kg/m3). Water absorption was most insufficient for 0% EPS blocks (4.39%) and highest for 20% EPS blocks (9.07%). The porosity was highest for 20% EPS blocks (14.37%) and lowest for 0% EPS blocks (6.74%). The heat passing rate was minimal for 0% EPS blocks and highest for 20% EPS blocks. Compressive strength was highest for 0% EPS blocks (13.37 MPa), moderate for 10% EPS blocks (10.87 MPa), and lowest for 20% EPS blocks (8.94 MPa). The unit cost of 100 blocks was highest for 0% EPS blocks (15.18 USD) and lowest for 20% EPS blocks (13.28 USD). Overall, the EPS blocks are recommended for construction due to their durability and compressive strength.