Mix design for recycled aggregate pervious concrete based on response surface methodology

This paper demonstrates that RSM can be used to design the mix proportion of recycled aggregate pervious concrete. From the perspective of the internal structure of recycled permeable concrete, the factors affecting its strength and porosity are the paste properties, the coating thickness of paste on the surface of aggregate and the void content of aggregate. Ideal paste thickness (IPT), actual coating thickness (ACT) and the void content (TVC) are respectively introduced to quantify and optimize these three factors through response surface methodology (RSM). Box-Behnken Design (BBD) is used to obtain the response of IPT and ACT to dosage combinations of three admixtures, and simplex centroid design is utilized to establish the response of TVC to different recycled aggregate gradations. Finally, three response surface models are optimized for practical application to find the suitable aggregate gradation and dosage combination of admixtures, and the verified experiment confirms that the model is effective. (C) 2020 Elsevier Ltd. All rights reserved.