【摘要】 目的为了揭示填石路堤的动力特性,合理设计填石路堤及路面结构.方法通过室内模型试验得到了动力荷载作用下填石路堤内部动应力分布规律以及动力荷载作用后路堤填料颗粒级配变化情况.再采用MARC有限元软件建立了动力荷载作用下填石路堤数值模型,选用Drucker-Prager弹塑性本构模型对填石路堤的动力特性进行了数值模拟.结果有限元可有效模拟动力荷载作用下填石路堤的应力分布规律,而对于填石路堤在动力荷载下的破坏表现为颗粒棱角的破碎以及细粒料漏失的破坏模式,数值模拟则只能采用塑性区表征.结论提出了确定填石路堤动力荷载影响区域的方法,并建议填石路堤上部应设置足够厚的整体性路面结构层次,避免长期汽车荷载作用下因填料棱角破碎和细粒料漏失而发生沉陷的病害.更多还原

【Abstract】 To reveal the dynamic properties of rock filling embankment and to improve the design for rock filling embankment and its pavement structure,model test indoor on the rock filling embankment is conducted.As the results of the test,dynamical stress distribution mode in rock filling embankment under dynamical loads and variation of grain size distribution of rock filling material of embankment after dynamical loads test are obtained in this paper.By modeling the rock filling embankment under dynamical load using MARC FEM software,choosing Drucker-Prager Elasticplastic model as constitution model of rock filling material,numeric simulation of rock filling material embankment was also conducted.Simulation results show that FEM can simulate the dynamical stress distribution mode properly,but can’t simulate the unique failure mode of rock filling material.For the main failure modes of the rock filling material under dynamical load are fracture of coarse grain and leaking of fine particle.So plastically deforming area was used to locate the failure area in FEM simulation.Combined the results of model tests and numeric simulation the area in embankment affected by dynamical load was marked.Further more,suggestions can be put forward that pavement should be thick enough to protect the rock filling embankment away from the influence of long term traffic to avoid the failure of the fracture of coarse grain and leaking of fine particle which leading pavement deterioration.更多还原