基于超声波法的冻融作用下冷再生混合料路用性能预测研究

Research on Road Performance Prediction of Cold Recycled Mixture under Freeze-Thaw Based on Ultrasonic Method

为精准预测冻融作用下冷再生混合料路用性能,分别对冻融作用下冷再生混合料进行路用性能试验及超声波检测,通过曲线拟合建立超声波速与高温贯入强度、低温劈裂强度、冻融劈裂强度比(freeze-thaw splitting strength ratio, TSR)的相关关系,并根据拟合公式分别对冷再生混合料路用性能指标进行预测。结果表明,冷再生混合料的超声波速随冻融循环次数的增加而明显降低,平均每增加5次冻融循环超声波速降低4%~6%;冷再生混合料高温贯入强度、低温劈裂强度及TSR的预测误差均保持在6%以下。超声波法预测冷再生混合料的路用性能具有一定的准确率及可靠性,是实现路面材料室内快速检测的一种良好方法。

In order to accurately predict the road performance of cold recycled mixture under freeze-thaw, the road performance test and ultrasonic test were carried out on the cold recycled mixture under freeze-thaw. Through curve fitting, the correlation between ultrasonic velocity and high temperature penetration strength, low temperature splitting strength and freeze-thaw splitting strength ratio(TSR) was established, and the road performance indexes of cold recycled mixture were predicted according to the fitting formula. The results showed that the ultrasonic velocity of cold recycled mixture decreased significantly with the increase of freeze-thaw cycles, and the ultrasonic velocity decreased by 4%-6% every 5 freeze-thaw cycles. The prediction errors of high temperature penetration strength, low temperature splitting strength and TSR of cold recycled mixture were kept below 6%. Ultrasonic method has certain accuracy and reliability in predicting the road performance of cold recycled mixture. It is a good method to realize the indoor rapid detection of pavement materials.