复杂轮胎力作用下沥青路面力学行为研究

发布时间：2017-12-31 13:01

本文关键词：复杂轮胎力作用下沥青路面力学行为研究　出处：《北京交通大学》2017年博士论文　论文类型：学位论文

【摘要】：随着我国经济的持续发展和地区间人货交流数量的增加,公路运输正向快速和重型化发展,车辆的高速重载现象日益严重。结合这一背景,有针对性地开展重交通荷载作用下的沥青路面力学行为研究,是道路工程学科和公路交通建设管理领域的迫切需求。在多数的路面力学行为研究中,轮胎力都被简化为静态均布垂向荷载,不能很好地适应重交通动态荷载作用下沥青路面设计与路表早期病害机理研究的特殊需求。将水平向轮胎力引入路面模型,以揭示复杂轮胎力作用下的路面力学行为,对于丰富和发展道路设计理论具有重要理论意义和工程应用价值。本文以复杂轮胎力及其作用下的沥青路面力学行为为对象,基于多体动力学方法和有限元方法分别建立了车辆、轮胎和道路的仿真模型,结合我国公路运输中车辆和道路的典型工况,从车辆-道路相互作用系统的角度进行了轮胎力和路面力学行为的研究,较全面地分析了车辆使用参数对轮胎力空间分布、路面动力响应及路面典型病害的影响。通过研究,得出以下主要结论:(1)轮胎接地压力可表达为三个方向的分力,即垂向接触力CPRESS、纵向摩擦力CSHEAR1、横向摩擦力CSHEAR2。稳态滚动条件下,上述三向接触力同时存在。轮胎处于自由滚动状态时,CSHEAR1和CSHEAR2与CPRESS处于同一量级。轮胎大部分的工作状态接近自由滚动,在进行轮胎和路面力学响应分析时不应忽略CSHEAR1和CSHEAR2。在完全制动和完全牵引状态下,CSHEAR1是水平向轮胎力的主要成分,CSHEAR2可以忽略不计。(2)CSHEAR1和CSHEAR2对路面面层的力学行为产生显著影响,尤其是增加了面层的等效应力幅值和TDC早期裂纹的等效应力强度因子,而半刚性材料层底的拉应力极值由垂向轮胎力控制,不受水平向轮胎力影响。(3)不同的车辆使用条件将产生不同的轮胎力空间分布特征,控制负载、增大胎压可有效改善轮胎的接地压力分布;道路条件也对轮胎力产生重要影响,CSHEAR1对路面摩擦系数和纵坡较为敏感,CSHEAR2对道路横坡较为敏感。(4)在高速公路运输中常见的参数条件下,货车的车速、装载率、胎压和道路纵坡对道路的使用性能产生显著的负面影响。低速、高胎压、超载均是促进车辙发生的直接原因;超载将加速TDC早期裂纹的扩展,高胎压则对裂纹的扩展没有显著影响。(5)车辆前轴对车辙和TDC早期裂纹的影响不容忽视,多轴并装车辆比单轴车辆更加容易导致车辙的发生。
[Abstract]:With the continuous development of our economy and the increase of the quantity of people and goods exchange between regions, highway transportation is developing rapidly and heavy-duty, and the phenomenon of high-speed and heavy load of vehicles is becoming more and more serious. It is an urgent need to study the mechanical behavior of asphalt pavement under heavy traffic load, which is an urgent need in the field of road engineering and highway traffic construction management. Tire forces are reduced to static uniform vertical loads. It can not meet the special needs of asphalt pavement design under heavy traffic dynamic load and the early disease mechanism of pavement surface. The horizontal tire force is introduced into the pavement model. In order to reveal the pavement mechanics behavior under the complex tire force action. It has important theoretical significance and engineering application value for enriching and developing road design theory. This paper takes the complex tire force and its mechanical behavior under the action of asphalt pavement as the object. Based on the multi-body dynamics method and the finite element method, the simulation models of vehicle, tire and road are established, and the typical conditions of vehicle and road in road transportation in China are combined. The tire force and pavement mechanical behavior are studied from the point of view of vehicle-road interaction system, and the spatial distribution of tire force caused by vehicle operating parameters is analyzed comprehensively. The main conclusions are as follows: 1) the earthing pressure of tire can be expressed in three directions, that is vertical contact force (CPRESS). Longitudinal friction CSHEAR1, transverse friction CSHEAR2. Under the steady rolling condition, the three directions contact force exists simultaneously. The tire is in the free rolling state. The CSHEAR1 and CSHEAR2 are of the same order of magnitude as the CPRESS. Most tyres are close to free rolling. CSHEAR1 and CSHEAR2 should not be ignored in the mechanical response analysis of tire and pavement. CSHEAR1 is the main component of horizontal tire force under the condition of complete braking and complete traction. CSHEAR2 can ignore that CSHEAR1 and CSHEAR2 have significant influence on the mechanical behavior of pavement surface. In particular, the equivalent stress amplitude of the surface layer and the equivalent stress intensity factor of the TDC early crack are increased, while the tensile stress extremum of the semi-rigid material bottom is controlled by the vertical tire force. Different vehicle use conditions will produce different tire force spatial distribution characteristics, control the load and increase the tire pressure can effectively improve the tire earthing pressure distribution. The road condition also has an important influence on the tire force. CSHEAR1 is more sensitive to the friction coefficient and longitudinal slope of the road surface. CSHEAR2 is more sensitive to the cross slope of the road. 4) under the condition of common parameters in the expressway transportation, the speed and loading rate of the truck. Tire pressure and longitudinal slope have a significant negative effect on the road performance. Low speed, high tire pressure and overload are the direct reasons to promote rutting. Overloading will accelerate the growth of early crack in TDC, while high tire pressure has no significant effect on crack propagation.) the influence of front axle of vehicle on rutting and early crack of TDC can not be ignored. Multi-axle mounted vehicles are more likely to cause rutting than single-axle vehicles.
【学位授予单位】：北京交通大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：U416.217

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