Application of recycled red brick as large aggregate for self-conpacting concrete with high volume fly ash

Abstract

Construction and renovation activities have resulted in a significant amount of red brick waste being generated into the environment. Meanwhile, global research has indicated that waste from red bricks can be utilized as aggregate for concrete to reduce costs, conserve resources, and protect the environment. In this paper, the author presents the results of experimental research on the use of recycled red bricks as aggregate for self-compacting concrete with a high proportion of fly ash. The study utilizes 100% recycled red bricks as coarse aggregate for self-compacting concrete, with a 50% volume fraction of fly ash. The properties are evaluated and compared with self-compacting concrete (SCC) via the use of natural stone, workability, compressive strength, flexural strength, chloride ion permeability, water absorption, and economic efficiency. The research results indicate that the use of 100% recycled brick aggregate can produce self-compacting concrete that meets European guidelines. This can be achieved by increasing the dosage of superplasticizer and utilizing high-content fly ash. The compressive strength decreases by 13.62%, the flexural strength decreases by 19.4%, the chloride ion permeability increases by 62%, and the water absorption increases by 39% compared to the control sample. Material and construction costs are lower and reduced compared to traditional concrete with the same strength, with reductions of 5.95% and 10.04%, respectively.