轮载作用下高寒地区沥青路面结构力学响应及损伤分析

发布时间：2018-12-30 22:24

【摘要】：高寒地区在我国分布广泛,具有高海拔、低气温、大温差、多日照、强辐射的气候特征,自然条件恶劣,同时己建成投入运营的高寒地区沥青路面病害严重,高寒地区沥青路面结构组合设计的合理选择至关重要。既有高寒地区沥青路面结构力学响应的分析尚欠全面,多未考虑粒料及土基的非线性,亦未充分结合环境、气候特征开展轮载作用下疲劳开裂、永久变形的损伤分析。本文在国内外研究现状全面调研的基础上,利用非线性有限元法、弹性层状体系理论等,主要开展了如下工作:(1)介绍了在国际上沥青路面结构分析发展历程中占据重要地位的轴对称非线性有限元软件MichPave(MFPDS之力学分析模块),包括其本构模型、自重应力与侧向应力、边界条件、网格剖分、应力修正与收敛准则、非线性层等效回弹模量及疲劳寿命与车辙深度预估等,为后续开展高寒地区沥青路面力学响应分析奠定了基础;(2)介绍了在国际上沥青路面结构分析发展历程中占据重要地位的弹性层状体系理论软件KENLAYER(KENPAVE之柔性路面分析模块),包括多轮荷载的迭加、粘弹性分析、非线性分析和损伤分析等,从而为后续开展高寒地区沥青路面结构损伤分析奠定了基础;(3)基于半刚性、夹层式、全厚式、倒装式四种典型高寒地区沥青路面结构,考虑倒装式结构级配碎石和四种结构土基的非线性,利用MFPDS软件建立了受轮载作用的轴对称非线性有限元模型,分析了这四种结构受荷载作用下的位移、应力、应变等力学响应,横向比较了其路用性能优劣;(4)考虑沥青面层的粘弹性、级配碎石和土基的非线性及轮载的移动性,运用KENPAVE软件,建立了基于弹性层状体系理论的半刚性、夹层式、全厚式、倒装式四种沥青路面结构轮致损伤分析模型,分别从疲劳开裂和永久变形两种损伤模式出发,开展了一年春夏秋冬四个时期、一个荷载组的损伤分析,讨论了路面温度、土基春融对损伤规律的影响,明确了路面控制损伤模式及损伤程度,横向比较了四种结构的损伤规律;(5)综合力学响应和损伤分析的结果,评析了高寒地区典型沥青路面结构的适应性,提出了高寒地区适宜的沥青路面结构组合设计的相关建议。
[Abstract]:Alpine region is widely distributed in our country. It has the climatic characteristics of high altitude, low temperature, big temperature difference, many sunshine, strong radiation, bad natural conditions, and the asphalt pavement in the alpine area, which has already been built and put into operation, is seriously damaged. The reasonable choice of asphalt pavement structure combination design in cold area is very important. The analysis of the mechanical response of asphalt pavement structure in alpine area is still incomplete, and the nonlinearity of granular material and soil foundation is not considered, nor is it fully combined with the environment, so the damage analysis of fatigue cracking and permanent deformation under wheel loading is carried out by climatic characteristics. In this paper, based on the comprehensive investigation at home and abroad, the nonlinear finite element method and the theory of elastic layered system are used. The main works are as follows: (1) the mechanical analysis module of axisymmetric nonlinear finite element software MichPave (MFPDS, which plays an important role in the development of asphalt pavement structure analysis, is introduced, including its constitutive model. Self-gravity stress and lateral stress, boundary condition, mesh division, stress correction and convergence criterion, equivalent resilience modulus of nonlinear layer, fatigue life and rutting depth prediction, etc. It lays a foundation for further analysis of mechanical response of asphalt pavement in alpine area. (2) the flexible pavement analysis module of elastic layered system software KENLAYER (KENPAVE, which plays an important role in the development of asphalt pavement structure analysis, is introduced, including the superposition of multi-wheel loads and viscoelastic analysis. The nonlinear analysis and damage analysis lay a foundation for the subsequent analysis of asphalt pavement structure damage in alpine area. (3) based on four typical asphalt pavement structures in high and cold region, including semi-rigid, sandwich, full thickness and inverted type, the nonlinearity of graded crushed stone and four kinds of structure soil foundation are considered. The axisymmetric nonlinear finite element model is established by using MFPDS software. The displacement, stress, strain and other mechanical responses of the four structures under load are analyzed, and the road performance is compared. (4) considering the viscoelasticity of asphalt surface, the nonlinearity of graded macadam and soil foundation and the mobility of wheel load, a semi-rigid, sandwich and full thickness formula based on the theory of elastic layered system is established by using KENPAVE software. Based on the two damage modes of fatigue cracking and permanent deformation, the damage analysis of a load group is carried out in four periods of spring, summer, autumn and winter, and the pavement temperature is discussed. The influence of spring melting of soil foundation on the damage law, the damage mode and damage degree of pavement control are defined, and the damage laws of four structures are compared horizontally. (5) synthesizing the results of mechanical response and damage analysis, the adaptability of typical asphalt pavement structure in alpine area is evaluated, and the relevant suggestions for the suitable combination design of asphalt pavement structure in alpine area are put forward.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U416.217

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