土基中波形梁护栏立柱的有限元模型研究

Finite Element Model of a W-beam Guardrail Post Mounted in Soil

论述了土基在车与波形梁护栏碰撞过程中起着重要的作用,波形梁护栏立柱与土基的相互作用缺乏有效的建模方法,建立土基的实体模型将导致单元规模的增大和求解时间的延长。在对土壤材料模型输出的压缩变形特性和屈服特性进行了测试的基础上,使用非线性有限元软件LS-DYNA对波形梁护栏圆形立柱与土基的相互作用进行了模拟,探讨了使用非线性梁单元来正确模拟车与波形梁护栏碰撞过程中立柱与土基的相互作用,土基与立柱的相互作用力可简化为:垂直于波形横梁板的分力(X方向);平行于波形横梁板的分力(Y方向),为研究车与波形梁护栏碰撞过程中土基对护栏安全性能的影响提供了一种有效的方法。

The importance of the soil behavior during a car-guardrail impact event is discussed. It is lack of effective modelling method for soil-post interaction, and it is expensive to include the soil FE model in the impact simulation.The volume change behavior and the yield strength of soil is tested, the soil-post interaction is simulated by using the FE softwore LS-DYNA, the discrete beam element is used to simulate soil-post interaction,The soil-post interaction primarily consisted of two dominant reaction components： soil-post force interaction vertical to the W-beam guardrail （X-direction） ; soil-post force interaction parallel to the W-beam guardrail （Y-direction）. It is an effective method to investigate the soil behavior during an car-guan＇trail impact.