Artificial Aggregate from Wood Waste for Concrete

Abstract

In recent years, a large quantity of wood-plastic composite (WPC) waste has been generated from the construction industry. Due to the composition of WPC—primarily plastic and wood powder—its recyclability is limited. This research aims to enhance the value of WPC waste by transforming it into artificial aggregates for partial replacement of natural coarse aggregates in concrete. The artificial aggregates were produced by melting WPC waste at 170 °C, allowing it to cool, and crushing it to pass through a 6 mm sieve. Concrete mixtures were prepared with a water-to-cement ratio (w/c) of 0.58 and a mix proportion by weight of cement : sand : aggregate = 1 : 2 : 4. Natural coarse aggregates were partially replaced with artificial aggregates at replacement levels of 5%, 10%, 15%, 20%, and 25% by weight. Concrete specimens were cast into 10 × 10 × 10 cm cubes and tested for compressive strength at curing ages of 7, 14, 21, and 28 days, as well as for density and water absorption at 28 days. The results indicated that compressive strength increased with curing time; however, higher replacement levels of artificial aggregate led to decreases in compressive strength and density, while water absorption increased. The findings suggest that artificial aggregates derived from WPC waste are suitable for non-structural concrete applications, such as masonry blocks, plant pots, curbstones, and outdoor furniture. This approach offers a sustainable alternative for reducing WPC waste and promotes the development of environmentally friendly construction materials.