摘要
文章以兰渝铁路某(82+172+82)m连续梁拱组合桥为工程实例,建立了考虑桩土共同作用的空间有限元分析模型,分别采用反应谱法和时程分析法对该桥进行地震计算,对比了两种分析方法的差异,研究了高阶振型、几何非线性、阻尼比及竖向地震作用等因素对铁路大跨连续梁拱组合桥地震响应的影响。结果表明:采用修正后的地震波进行时程分析,拱脚截面和墩底截面计算内力与反应谱法计算结果差异在20%以内;在纵、横向地震作用下桥梁地震反应由前30阶振型控制,竖向地震作用下桥梁地震反应由前70阶振型控制;阻尼比对钢管混凝土拱桥的地震响应影响较显著;几何非线性对该桥地震响应的影响最大为2.21%;竖向地震作用对截面轴力和面内弯矩起控制作用,最大放大倍数为2.88倍。
The paper takes a continuous beam and arch bridge with spans of（ 82 ＋ 172 ＋ 82） m on Lanzhou-Chongqing railway as an engineering example,response spectrum analysis and time history analysis method is used respectively to calculate the seismic response,differences between two methods is compared,influence of factors such as the high order modes,geometry nonlinear and vertical seismic action on seismic responses of railway long-span continuous beam and arch bridge is studied. The results show that the calculated result difference by two kinds of analysis methods is within20%. The bridge seismic response is mainly controlled by the top 30 order mode under the action of vertical and horizontal earthquake and by the top 70 order mode under the action of vertical earthquake. The largest effect of geometric nonlinearity on the seismic response of the bridge is 2. 21%; Vertical seismic action has control action on axial force and plane bending moment with magnification up to 2. 88 times.
出处
《高速铁路技术》
2016年第2期36-41,共6页
High Speed Railway Technology
关键词
连续梁拱组合桥
地震响应
高阶振型
几何非线性
竖向地震作用
combined bridge with continuous beam and arch
seismic response
high order modes
geometric nonlinearity
vertical seismic action
