Study on the Performance of Cement-Stabilized Waste Concrete and Clay brick Aggregates as Road Base Course

摘要

The aim of this study is to make utilization of the waste concrete and clay brick as aggregates for cement-stabilized road base course. After crushing and sieving, the waste concrete, waste clay brick, and crushed stone were made into six kinds of aggregates with the same gradation separately or mixed with each other based on different proportions. After the aggregates were mixed with cement of 5%, the maximum dry density (MDD) and the optimum moisture content (OMC) were confirmed respectively. Then, specimens were prepared and 7d, 28d, 90d and 180d unconfined compressive strengths (UCS), 28d, 90d and 180d splitting strengths and Compressive resilience modulus as well as freezing resistance performance were carried out on the specimens. The results indicated that waste concrete and clay brick aggregates are of relatively high crushing value and water absorption rate but low density. In the mixture containing a large amount of such aggregates, the MDD declined with the increased OMC. Although both the waste concrete and clay brick aggregates affected the UCS, compressive resilience modulus, freezing resistance and splitting strength of mixture, the impact on the first three was greater than that on the last one. When the aggregates of this kind are adopted as the cement-stabilized base course material, it's recommended to use crushed stones for coarse aggregates, and use waste concrete and clay brick for fine aggregates. In the cold area, waste concrete and clay brick aggregates should be used as raw material of cement stabilized materials cautiously.