沥青混合料冻融损伤模型及寿命预估研究

Research on Freeze-thaw Damage Model and Life Prediction of Asphalt Mixture

为研究沥青路面抵抗冻融损害的能力,结合损伤理论,进行了沥青混合料冻融损伤模型及残余寿命预估的研究。建立了适用于冻融条件下沥青混合料损伤的普适模型,并提出了相应算法;然后根据快速冻融作用下混合料的各性能试验结果对该模型进行了验证;最后提出了模型应用于混合料冻融损伤后寿命预估的方法。结果表明:随冻融循环次数增加,沥青混合料性能衰减,损失度增大;模型能较好的拟合沥青混合料冻融循环后各项性能指标的变化;宜将抗压回弹模量作为评价混合料抗冻融损坏能力的和寿命预估的主要指标。

To research the resistance ability to freeze-thaw damage of asphalt pavement,freeze-thaw damage model and residue life prediction of asphalt mixture was researched with damage theory.The universal damage model of asphalt mixture was established under the freeze-thaw condition,and the corresponding calculation algorithm was proposed.Then,the model was validated to be efficacious according to kinds of performance test results under rapid freeze-thaw condition.Finally,the practical application of the model in life prediction after freeze-thaw damage was put forward.The results show that（1） the performance of asphalt mixture weakens and loss degree increases with the increases of freeze-thaw cycles;（2） the model could fit to performance index change of asphalt mixture after freeze-thaw cycles preferably;（3） the compressive modulus could be considered to be the important index to evaluate the resistance ability to freeze-thaw damage and life prediction of asphalt mixture.