旧沥青路面材料柔性底基层力学及抗裂性能研究

发布时间：2018-02-03 00:42

本文关键词： 旧沥青路面材料(RAP) 路面结构组合设计应力水平承载能力反射裂缝应力强度因子　出处：《河北工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：废旧沥青路面材料再生利用技术是解决废料回收利用和环境污染的有效途径,然而再生混合料兼有性能较弱和水稳定性差等不足,易发生早期破坏。随着具有非线性特性及抗裂性能的粒料类材料的广泛应用,文章提出了全比例RAP材料作为改建道路柔性底基层路面结构的设想。论文首先阐述了RAP掺配比对再生混合料影响和粒料夹层延缓路面反射裂缝的国内外研究现状。其次,分析RAP材料作为柔性底基层的合理性,并对其结构层内竖向应力的分布规律及考虑超载影响的竖向应力水平范围进行研究,进而利用粒料类材料的永久变形预估模型分析其塑性变形情况。然后,进行RAP材料试验研究,分析评价RAP材料的级配组成,确定试验路段RAP柔性底基层的合理级配。此外,对RAP材料的基本力学性能和承载能力进行分析计算,确定RAP材料的回弹模量,并得到RAP材料层回弹模量与压实度之间的相关性。最后,利用有限元软件ANSYS,结合线弹性断裂力学理论,对路面结构内部存在裂缝缺陷的RAP柔性底基层沥青路面进行数值仿真计算。通过互动积分法得到在正、偏荷载作用下裂纹尖端应力强度因子(KI、KII)随RAP底基层厚度、模量和超载率变化的规律,并结合沥青路面结构组合设计的设计标准,最终确定RAP材料用作改建道路底基层时合理的层厚与模量,得到改建道路全比例RAP柔性底基层沥青路面的典型结构,供实际应用参考。
[Abstract]:Recycling technology of waste asphalt pavement materials is an effective way to solve waste recycling and environmental pollution. However, recycled mixture has some shortcomings, such as weak performance and poor water stability. Early failure is easy to occur. With the wide application of granular materials with nonlinear properties and crack resistance. This paper puts forward the assumption that the fully proportional RAP material can be used to reconstruct the pavement structure of the flexible base course of road. Firstly, the paper expounds the influence of RAP blending ratio on the recycled mixture and the effect of granular interlayer on the reflective crack of road surface at home and abroad. Research status. Second. The rationality of RAP as a flexible base is analyzed, and the distribution of vertical stress in the structure layer and the horizontal range of vertical stress considering the influence of overload are studied. Then, the plastic deformation of granular materials is analyzed by using the permanent deformation prediction model. Then, the RAP material test is carried out to analyze and evaluate the gradation composition of RAP materials. In addition, the basic mechanical properties and bearing capacity of RAP materials are analyzed and calculated to determine the resilience modulus of RAP materials. The correlation between the elastic modulus and compaction of RAP material layer is obtained. Finally, the finite element software ANSYSand the theory of linear elastic fracture mechanics are used. The RAP flexible base asphalt pavement with internal crack defects is numerically simulated and the stress intensity factor (SIF) of crack tip is obtained by the interactive integration method under positive and partial loads. KII) changes with the thickness, modulus and overload rate of RAP base, and combines with the design standard of asphalt pavement structure combination design. Finally, the reasonable layer thickness and modulus of RAP material for reconstruction of road base are determined, and the typical structure of fully proportional RAP flexible base asphalt pavement is obtained for practical reference.
【学位授予单位】：河北工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U414;U416.217

【共引文献】