Performance and Life Cycle Cost Analysis of Recycled Concrete Utilising Waste Clay Brick

The increase of solid construction waste in the world is a serious problem affecting the environment. Many scholars have studied and developed methods for recycling construction waste, one of which is to use it as a substitute for natural aggregate in concrete materials. The goal of this research is to study the feasibility of using waste clay brick as recycled coarse aggregate (RCA) to prepare concrete and to evaluate the life cycle cost of using this recycled concrete. Four series of concrete samples with different substitution rates (0, 50, 70 and 100%) of natural coarse aggregate by RCA made from waste clay bricks were manufactured for this study. The workability, mechanical properties and thermal properties of the concrete samples were studied. Results showed that the strength of concrete prepared with recycled aggregates decreased, but it can basically meet the strength requirements of ordinary concrete. According to the results of strength and thermal performance, 70% is the optimal dosage for recycled aggregates. The life cycle cost of recycled concrete with recycled aggregate was then analysed based on production cost, transport cost and environmental cost. The findings indicated that the use of this recycled concrete material in concrete structures led to save transportation and environmental costs. It revealed that recycled concrete with a high replacement rate of recycled aggregate has more advantages in energy consumption and pollution gas emission. The study showed that it is feasible in technology and environment to produce sustainable recycled concrete using waste clay bricks.