CRC-AC复合式路面沥青层反射裂缝影响因素分析

应用有限元软件ABAQUS建立有限元模型,采用断裂力学理论及奇异等参元法,对连续配筋混凝土和沥青混凝土(CRC-AC)复合式路面中沥青层反射裂缝问题进行了数值分析。探讨了I型和II型的应力强度因子(K1、K2)在沥青层裂缝扩展过程中的变化规律及路面结构参数对K2的影响。研究结果表明:K2是荷载作用下导致沥青层反射裂缝产生和发展的主要原因,其随着荷位的增大而变小;沥青层厚度的增加、横向裂缝间距的加宽、配筋率的适当增加和底基层强度的提高可以降低K2,延缓CRC-AC复合式路面沥青层反射裂缝的开裂扩展。

Analysis of Factors to Reflection Crack of AC Layer in CRC-AC Compound Pavement

A finite element analysis model was established by the FEM software ABAQUS and the reflection crack of AC layer in Continuously Reinforced Concrete-Asphalt Concrete(CRC-AC) compound pavement was numerically analyzed with the fracture mechanics theory and singularity isoparametric elements method.The change of the stress intensity factor(SIF) of model I(K1)and model II(K2)in the course of AC layer reflection crack propagation was discussed and the effect of pavement parameters on K2 was studied.The results show that K2 takes the main responsibility for reflection crack and decreases as the distance of load position increases.Adding thickness of AC layer,widening transverse cracks,increasing steel ratio properly and enhancing subbase strength,K2 will be decreased,which can prevent the initiation and expanding of reflection crack of AC layer in CRC-AC compound pavement effectively.