摘要
为研究跨断层桥梁地震响应规律及合理跨越断层角度,以一座跨走滑断层的连续梁桥为研究对象,采用混合模拟法合成了该桥的地面运动时程曲线,基于多点激励位移输入模型,采用非线性时程法对其地震响应规律进行了分析,并以桥梁轴向与断层交角θ为研究参数分析了其对结构地震响应的影响,得到了θ对结构地震响应的影响规律和变化曲线。计算结果表明:跨断层桥梁桥墩扭矩设计值较大,桥墩横向弯矩随断层距的减小而增加;其位移响应以主梁纵横向大位移、面内扭转变形、支座和桥墩残余位移为主要特征,具有较大的落梁破坏风险;当桥梁垂直跨越断层时(θ=90°),桥墩受力合理性和经济性最优,断层错动产生的顺桥向位移分量最小,落梁风险相对较低。研究成果可为该类桥梁的抗震设计与桥位布置提供参考和依据。
Here,seismic response features and best crossing angles for bridges crossing faults were presented.One bridge crossing a strike-slip fault was taken as an example.The seismic ground motions at the site of the bridge were generated with the hybrid simulation methodology.Multi-support excitation displacement input models and the nonlinear time history analysis were used to calculate the seismic response of the structure.The influences of the crossing angle θbetween bridge axis and fault on its seismic response were analyzed,the influence law and variation curve were acquired. The results showed that the designed pier torques of the bridge are larger;the pier transverse bending moment increases with decrease in fault distance;the displacement response has the main characteristics of large vertical and lateral displacements and in plane torsional deformation of the main girder,and residual displacements of bearings and piers with significant unseating risks;when the bridge vertically crosses the fault（θ=90°）,the force-bearing reasonableness and economy of piers are optimal,the bridge axial displacement components caused by fault dislocation are minimum, accordingly,the unseating risk is relatively lower.The results provided a reference for a seismic design and locating of bridges.
出处
《振动与冲击》
EI
CSCD
北大核心
2015年第13期6-11,17,共7页
Journal of Vibration and Shock
基金
科技部国际科技合作项目(2009DFA82480)
交通运输部西部交通建设科技项目(2009318223094)
交通运输部公路工程行业标准项目(JTG-C-201012)
关键词
桥梁工程
跨断层
地震响应
跨断层交角
bridge engineering
across faults
seismic response
crossing angle between bridge and fault
作者简介
惠迎新 男，博士生，1985年生
通信作者 王克海 男，博士，研究员，博士生导师，1964年生
