Lightweight concrete masonry with recycled wood aggregate

Waste wood sent to landfills represents a potentially valuable resource for construction materials. This paper reports progress in the use of recycled wood aggregate for concrete block. The project goal was to use standard concrete block manufacturing procedures to produce a lightweight block meeting the requirements of ASTM C129 for non-loadbearing concrete masonry. Trial cylinders were made in a laboratory simulation of block plant processes to evaluate admixtures and wood treatments, then promising mixes were used to make several batches of blocks in a commercial plant. Cylinders and blocks were tested for compressive strength, and the blocks were subjected to wet-dry cycling. Results indicate that weight, strength, and durability targets were met. Questions remain regarding the economic performance of the product, and further study is required to evaluate the effect of curing blocks in the uncontrolled exterior conditions typical of the block industry.