Recycling Waste Paver Blocks in the Manufacture of New Concrete Paver Blocks and Building Bricks

This study investigates the feasibility of recycling various waste paving blocks as raw materials for concrete. The recycling rate of waste blocks in Korea remains around 11%. Therefore, three types of waste paving blocks, i.e., recycled clay-, granite-, and concrete block, were used as partial replacements for sand in a concrete mixture at 10%, 20%, and 30% replacement ratios. According to the Korean standards for concrete pavers and building bricks, compressive strength, flexural strength, and water absorption tests were conducted. In addition, UPV and unit weight tests were performed. The results showed that the performance of concrete mixtures decreased with the increasing replacement ratio of waste clay and concrete, while the addition of waste granite improved the properties of the mixtures. All the prepared concrete mixtures met the requirements specified in the standards, demonstrating that concrete incorporating waste blocks can be used as paving blocks and building bricks under limited conditions.