旧水泥路面共振破碎加铺沥青力学响应分析

Analysis on Mechanical Response of of Asphalt Overlay in Resonance Crushing of Old Cement Pavement

摘要:

共振破碎技术是处理旧水泥路面的有效手段，可消除沥青加铺层的反射裂缝问题，实现旧板块的原位利用，能降低工程造价缩短施工工期，因此而受到了广泛关注。掌握各共振破碎层对结构层的力学响应，可更大限度的发挥各结构层的功能，有效防止路面病害的产生。通过ABAQUS有限元软件建立含共振破碎层（松散层+嵌锁层）的沥青加铺层结构模型，分别探究不同松散层、嵌锁层和破碎层的模量和厚度对加铺结构的力学响应。研究发现：松散层的回弹模量、松散层相对厚度对加铺结构的力学响应影响显著，而嵌锁层的模量对加铺结构影响较小。应控制上部松散层的模量在300 MPa以上，嵌锁层的模量在2 500 MPa以上以及松散层占共振破碎层总厚度1/3左右。此外，在加铺层结构设计时，将共振破碎层作为双层结构考虑比单层结构更加安全可靠。

Abstract:

The resonance crushing technology is an effective mean to treat the old cement pavement, which can eliminate the problem of reflection cracks in asphalt overlay, achieve the in-situ utilization of old slabs, reduce the engineering costs and shorten the construction periods, and has received the widespread attention. Mastering the mechanical response of each resonant crushing layer to the structural layer can maximize the functionality of each structural layer and effectively prevent the occurrence of pavement diseases. A structural model of asphalt overlay with resonant crushed layer (loose layer+embedded layer) is established by ABAQUS finite element software to explore the mechanical response of different loose layer, embedded layer, and broken layer moduli and thickness to the overlay structure. The research has found that the rebound modulus and the relative thickness of the loose layer have a significant impact on the mechanical response of the overlay structure. The modulus of the embedded layer has has little effect on overlay structure. The modulus of the upper loose layer should be controlled above 300 MPa. The modulus of the embedded layer should be above 2 500 MPa. And the loose layer should account for about one-third of the total thickness of the resonant crushing layer. In addition, it is safer and more reliable to consider the resonant crushing layer as a double-layer structure than a single-layer structure in the design of overlay structure.