高速公路沥青面层混合料开裂性能指标试验研究

Research on Cracking Performance Index of Asphalt Surface Mixture of Expressway

文章通过低温间接拉伸蠕变试验和路面抗裂性能(OT)试验对通车年限相同、地理环境相近但不同沥青面层结构的高速公路沥青面层混合料芯样进行了不同角度的试验分析研究,得出了相对应的试验性能指标。结果证明,蠕变柔量和开裂损失率指标可有效预测和评价沥青面层混合料开裂现象,即在相同试验温度条件下,SMA-13级配沥青混合料蠕变柔量大于AC-16和AC-20级配沥青混合料蠕变柔量,且AC类沥青混合料的低温蠕变柔量变化快于SMA类沥青混合料,而抗开裂性能指标中AC-16与AC-20级配沥青混合料相近,SMA-13级配沥青混合料抗开裂性能损失程度最小,因此加铺SMA结构的沥青混合料面层结构适应变形的能力强,沥青路面不易开裂。

In this paper,through indirect tensile creep test at low temperature and OT test,the core samples of expressway asphalt pavement mixtures with the same service life,similar geographic environment but different asphalt pavement structures are analyzed from different angles,and the corresponding test performance indicators are obtained.The results show that creep compliance and cracking loss index can effectively predict and evaluate the cracking phenomena of asphalt mixtures.That is to say,under the same test temperature,the creep compliance of SMA-13 graded asphalt mixtures is greater than that of AC-16 and AC-20 graded asphalt mixtures,and the creep compliance change of AC type asphalt mixtures is faster than that of SM at low temperature.Class A asphalt mixture,while the anti-cracking performance index AC-16 and AC-20 graded asphalt mixture is similar,SMA-13 graded asphalt mixture load loss is the smallest,so the asphalt surface mixture structure with SMA structure has a strong capability to adapt to deformation,and asphalt pavement is not easy to crack.