Abstract

A procedure for assessing the structural adequacy of semi-rigid barriers, consisting of the determination of load-carrying capacity using plastic analysis and the calculation of the impact load, is presented. To reflect the dynamic effects of the soil, the plastic moment of posts is defined by multiplying the dynamic resisting force of a post by the distance from the impact loading point to the position of a plastic hinge. The impact load was determined by using a modified Olson model, idealizing the vehicle lateral acceleration-time relationship as a triangle instead of the half-sine function of the Olson model. For semi-rigid vehicle barriers with relatively small lateral stiffness, the proposed structural adequacy assessment procedure and FEA provided approximately the same results. However, for semi-rigid vehicle barriers with large lateral stiffness, the assessment procedure using the first impact load, different from the assumption of the modified Olson model, produced a rational design.

摘要

介绍了评估半刚性屏障结构充分性的程序，包括使用塑性分析确定承载能力和计算冲击载荷。为了反映土体的动力作用，柱子的塑性力矩定义为柱子的动态阻力乘以冲击加载点到塑性铰位置的距离。冲击载荷是通过使用改进的 Olson 模型确定的，将车辆横向加速度-时间关系理想化为三角形而不是 Olson 模型的半正弦函数。对于侧向刚度相对较小的半刚性车辆护栏，所提出的结构充分性评估程序和有限元分析提供了大致相同的结果。然而，