关键词: 再生砖骨料, 寒区路用性能, 响应面法, 拟合模型, 多目标优化

Abstract: Abandoned clay bricks as recycled aggregates in concrete can effectively mitigate the environmental pollution caused by construction waste. By taking 5-10mm and 10～20 mm recycled brick aggregates as independent variables and water-cement ratio as a factor, the road performance parameters such as compressive strength, abrasion resistance, and frost resistance are considered as objectives. The impacts of various factors are determined by applying a central composite experimental design. The experimental results are regressed and a fitting model is proposed to describe the relationship between the factors and the road performance of concrete. The reliability and stability of the model are validated through variance analysis. A thorough analysis of the model is performed using a response surface 3D plot to determine the impact of the factors on the three road performance parameters of recycled brick aggregate concrete in cold regions. The influencing factors are ranked from high to low as follows: water-cement ratio, 10～20 mm brick aggregate, and 5～10 mm brick aggregate. Optimizing the road performance of cold region regenerated brick aggregate concrete involves meeting three requirements for cold region road conditions: maximizing compressive strength and frost resistance, maximizing wear resistance while maintaining excellent compressive strength and frost resistance, and emphasizing frost resistance based on assigned weights. The results show the proposed fitting model can be used to obtain the optimal mixture ratio based on engineering objectives, optimizing the preparation process of recycled brick aggregate concrete and providing a theoretical reference for its practical application in engineering fields.