作　　者： (刘飞）; (罗旗帜）; (蒋志刚）; (严波）;

机构地区： 湖南大学土木工程学院,湖南长沙410082 国防科学技术大学指挥军官基础教育学院,湖南长沙410072

出　　处： 《地震工程与工程振动》 2017年第4期112-120,共9页

摘　　要： 车辆撞击已成为世界范围内桥梁破坏的重要原因之一,桥梁防撞设计具有十分紧迫的工程需求。本文基于Euler-Bernoulli梁理论和Winkler地基模型,建立了考虑桩周地基土和墩柱轴压力影响的桥墩动态弹性响应模型;采用Laplace变换和逆变换相结合的方法进行数值求解,得到了桥墩的撞击动态响应,分析了地基土剪切波速、轴压力、桩径和桩长对桥墩撞击响应的影响。研究表明,地基土剪切波速和桩径对桥墩撞击响应有重要影响,桥墩变形和柱底截面最大弯矩均随剪切波速和桩径的增大而减小,撞击点截面剪力随剪切波速和桩径的变化很小;在实际桥墩的轴压比范围内,轴压力对桥墩撞击响应的影响很小;桥墩变形随桩长的增加而增大,桩长对柱底弯矩和撞击点截面剪力的影响很小。 Vehicle collisions had been one of the important causes which led the bridge damage. There had urgent engineering demands on bridge design against vehicle collisions. Based on the Euler-Bernoulli beam theory and the Winkler foundation model, the impact model of the pier subjected to vehicle collisions was established, which had considered the influences of soil around the pile and axial force. The dynamic responses of the pier were derived by direct and inverse Laplace transforms, respectively. The effects of the soil＇ s shear wave speed, the axial load, the pile diameter and the pile length were investigated. The results showed that the soil＇ s shear wave speed and the pile diameter had important influences on the pier＇ s dynamic response. The deformation and the maximum moment at the bottom of the pier both decreased with the increase of the shear wave speed and the pile diameter, which had little influences on the shear force at the impact point. The influence of the axial force to the pier＇ s dynamic response is very small in the range of axial compression ratio of constructed piers. The pier＇s deformation increased with the pile diameter increased, the pile diameter had little influences on the moment at the bottom of the pier and the shear force at the impact point.

关 键 词： 桥墩 撞击 地基土 轴压力 理论模型