摘要
常见的落石防护结构如拦石墙、棚洞等往往上覆一定厚度的缓冲土层,以避免落石直接冲击结构造成结构损坏,因此落石冲击荷载在缓冲土层中的扩散特性成为落石防治结构设计必须考虑的重要因素之一.室内物理模型试验与颗粒流程序数值仿真模拟相结合,对不同落石半径、坠落高度、缓冲土层布置条件下落石冲击荷载在缓冲土层中的扩散形式和扩散角度进行了分析.结果表明:落石冲击荷载在缓冲土层中一般以圆锥形进行扩散,不同的缓冲土层材料中其扩散角度存在一定差异;数值仿真模拟与试验结果基本一致,误差在5%~10%之间;与已有的研究成果相比,扩散角均与缓冲材料的内摩擦角相关,但本次研究发现其扩散角度相对偏大.
The common rockfall protective structures,such as retaining walls and shed tunnels,are often overlaid with a certain thickness of cushioning soil to avoid structural damage caused by direct impact of rockfall.Therefore,the diffusion characteristics of impact load of rockfall in cushioning soil become one of the important factors to be considered in the design of rockfall prevention structure.Combing laboratory physical model test with numerical simulation of particle flow code(PFC),the diffusion form and angle of impact load of rockfall in cushioning soil under different radius,height and layout of cushioning soil layer are analyzed.The results show that impact load of rockfall generally diffuses with a conical shape in cushioning soil,and there are some differences in the diffusive angle among different cushioning soil materials.The simulation results are consistent with the that of experimental,and the error is between 5%and 10%.The diffusion angle is related to the internal friction angle of the cushioning material.The study reveals that the diffusion angle is relatively large than the previous research results.
作者
王南南
江巍
王彦海
陈玮
WANG Nannan;JIANG Wei;WANG Yanhai;CHEN Wei(Hubei Key Laboratory of Disaster Prevention&Mitigation,China Three Gorges Univ.,Yichang 443002,China)
出处
《三峡大学学报（自然科学版）》
CAS
北大核心
2020年第2期46-51,共6页
Journal of China Three Gorges University：Natural Sciences
基金
国家自然科学基金项目(51409150)
防灾减灾湖北省重点实验室(三峡大学)开放基金(2017KJZ03)。
关键词
冲击荷载
扩散特性
颗粒流程序
数值仿真
扩散角度
impact load
diffusion characteristics
particle flow code
numerical simulation
diffusion angle
