In China semi-rigid base course material accounts for 95% of subbase material in various grade highwayu at present. Though with the advantage of high strength plate and good freezing resistance, semi-rigid asphalt road is easy to crack because of shrink and low-temperature crack. Many measures have been taken including increasing the thickness of asphalt surface, using link structure or stress-absorbing interlayer and so on. But the focus of these measures are different and the function mechanisms are various.3-D Finite Element Modeling is used to model and analyze the typical road structure. Continuity and completely smooth state are considered. Under least favorable load condition, the influence of asphalt surface thickness on stress state of bottom of pavement is analyzed. Analysis shows that solely incerease the thickness of pavement is not the effective measure to postpone the reflective crack. The result also indicates the importance of adhesive property between layers. Though analysis also shows the rational thickness and modulus of stress-absorbing interlayer, and the adhesive strength is emphasized.%半刚性材料目前占到我国各等级公路路面基层材料用量的95%以上,半刚性基层沥青路面虽然具有板体强、抗冻性好等诸多优点,但是容易出现反射裂缝.国内外对半刚性基层沥青路面反射裂缝的防治包括增加沥青面层厚度、在基层与面层之间增加级配碎石层或应力吸收中间夹层等多种方式.这些措施的侧重各有不同,综合利用多种防裂措施与方法可以达到最佳的防裂措施.力图通过三维有限元建模分析,分别考虑层间连续和层间光滑两种状态,施加正荷载和偏荷载,用以分析典型路面结构中路面厚度对面层底部受力状态的影响,得出单纯增加路面厚度并非最佳防裂手段,并论证了保持良好层间粘结对与延缓反射裂缝的重要意义.并通过荷载作用下加铺应力吸收层的路面结构的力学分析,提出了合理的应力吸收层厚度和模量,指出应力吸收层与半刚性基层粘结良好的重要性.
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