Study of the mechanical properties of pervious concrete with a rice husk ash–metakaolin composite admixture

Abstract

Abstract In this paper, the influences of rice husk ash and metakaolin on the mechanical properties of pervious concrete are studied, a balance between compressive strength and the pervious coefficient is found, the reuse of industrial waste residue from rice husk ash is realized, and the mechanical properties of pervious concrete are improved. The response surface test method is used to study the influences of rice husk ash and metakaolin on the compressive strength and perviousness coefficient of the pervious concrete specimen. The response surface experiment method was used to optimize the mix ratio of pervious concrete. The results reveal that the optimal contents of rice husk ash and metakaolin in the mixed pervious concrete test group optimized by the response surface test method is 9.2% rice husk ash and 8.2% metakaolin, with a water-to-binder ratio of 0.41. These parameters increase the compressive strength by 10% compared with that of the reference group under the same conditions, and they meet the requirements of the C20 concrete technical specification for pervious cement concrete pavement. Thus, this material can be applied to both urban and highway pavement. Herein, new concepts and technical references for the development and application of pervious concrete are provided.