泥石流冲蚀桥墩防护格栅模型试验研究  

Model testing of protective grilles for debris flow erosion on bridge piers

作　　者：谢涛 刘俞琳[2] 黄琦 XIE Tao;LIU Yulin;HUANG Qi(Key Laboratory of Geological Hazards Mitigation for Mountainous Highway and Waterway,Chongqing 400074,China;College of River and Ocean Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]山区公路水运交通地质减灾重庆市高校重点实验室,重庆400074 [2]重庆交通大学河海学院,重庆400074

出　　处：《地震工程学报》2025年第2期342-350,共9页China Earthquake Engineering Journal

基　　金：国家自然科学基金(41807272);第二次青藏高原综合科学考察项目(2019QZKK0902);重庆市研究生联合培养基地建设项目(JDLHPYJD2022004)。

摘　　要：泥石流对桥墩的冲击破坏能力与其流速、固相物质含量及颗粒组成有关。基于此,从防护桥梁桥墩角度,提出一种新型的泥石流冲蚀桥墩防护格栅,新型格栅可持续对泥石流固相颗粒进行调控,使泥石流固相颗粒粒径减小、容重和冲击力降低,可有效保护桥墩。在室内开展一系列模型实验,研究格栅引流角度、格栅跨度等结构参数对防护效果的影响。结果表明:(1)随引流角度增大,格栅内侧泥石流容重降低率和粗颗粒含量减小率均先增大后减小,具有二次函数关系;(2)随格栅跨度增大,容重率逐渐降低,粗颗粒含量逐渐减小,并具有线性关系;(3)泥石流在格栅处的冲起高度,随格栅与开口间距增大而逐渐减小,两者之间存在指数函数关系;冲起高度随引流角度增大而逐渐增大,两者之间具有线性关系。文章结合理论分析,建立新型格栅各个结构参数的取值方法,为工程设计提供依据。The impact and destructive capacity of debris flow on bridge piers are influenced by factors such as debris flow velocity,solid matter content,and solid particle composition.On this basis,a novel protective grille designed to shield bridge piers from debris flow erosion is proposed.The protective grille works by continuously regulating the solid particles in the debris flow,reducing the bulk density,the solid particle size,and impact force,thereby effectively protecting the bridge piers.A series of laboratory model tests were carried out to investigate the impact of structural parameters on the protection effect.Results indicate that:(1)As the drainage angle increases,the reduction rates of bulk density and coarse particle content in the debris flow within the grille initially increase and then decrease,following a quadratic function relationship;(2)As the grille span increases,the reduction rates of bulk density and coarse particle content consistently increase,displaying a linear relationship;(3)The scour height of the debris flow at the grille decreases as the relative opening spacing of the grille increases,showing an exponential function relationship.By contrast,the scour height gradually increases with the drainage angle,exhibiting a linear relationship.Meanwhile,through theoretical analysis,a method was developed to determine the structural parameters of the novel grille,including the drainage angle,span,height,and spacing.This approach provides a foundation for engineering design.

关 键 词：泥石流 桥墩 冲击 磨蚀 

分 类 号：P642.23[天文地球—工程地质学]