摘要
针对大跨度小半径曲线梁桥轴向变形、平面内弯曲、竖向挠曲与扭转同时存在,较普通梁桥受力性能复杂,在地震作用下容易出现事故的特点,以某实际工程快速路高架为背景,对这段高架中的L14联(38+70+38 m,位于半径R=100 m圆曲线上)的大跨度小半径曲线预应力混凝土连续箱梁桥进行三维实体建模;利用有限元分析理论,对三维实体模型进行模态分析,研究其动力特性和一维与多维地震激励响应,并将二者结果进行对比分析。结果表明:大跨度小半径曲线梁桥地震激励下,弯扭耦合作用极为明显,对横桥向地震激励最为敏感,其更容易发生桥梁侧翻、支座脱空、横向滑移、扭转翘曲等严重桥梁病害,在设计施工都需着重注意。
Aiming at the characteristics of large-span,small-radius curved girder bridges which are morecomplicated than ordinary girder bridges,axial deformation,in-plane bending,vertical deflection and torsion exist simultaneously,and the accident is prone to occur under earthquake action. Taking the actual project Engineering Expressway Elevated for the engineering background,3 D solid model is built for this section of the elevated L14(38 m + 70 m + 38 m,located in the radius R = 100 m circular curve) of the large-span small radius Dimensional prestressed concrete continuous box girder bridge. The finite element method is used to analyze modal,the dynamic characteristics and both one-dimensional and multi-dimensional seismic excitation response. Besides,the results are compared. The result shows that the large span small radius curved girder bridge under seismic excitation,coupling is very obvious. The transverse seismic excitation is the most sensitive. The bridge is more prone to rollover,bridge bearing cavity,lateral slip and torsion warping. So it is required to pay attention to in design and construction.
出处
《公路工程》
北大核心
2018年第1期244-250,共7页
Highway Engineering
关键词
曲线梁桥
大跨度
小半径
地震时程分析
有限元
curved beam bridge
large span
small radius
seismic time history analysis
finite element method