某大跨度公铁两用斜拉桥的地震响应研究

发布时间：2018-12-21 19:22

【摘要】：我国位于世界两大地震带之间,受太平洋板块、印度板块以及菲律宾海板块的挤压,地震断裂带十分发育,地震灾害严重。桥梁作为交通网络的组成部分,在生命线抗震防灾体系中起着至关重要的作用,且大跨度桥梁与传统桥梁相比,其投资更大、成本更高、施工过程也更加复杂,因此抗震要求也更高。沪通公铁两用长江大桥是一座正在建设的公铁两用大跨度斜拉桥,为中国沿海铁路的过江通道。上层六车道公路为锡通高速公路,最大时速100 km/h,下层四线铁路为通苏嘉城际铁路和沪通铁路,最大时速200 km/h。该桥全长2300 m,跨径达1092 m,建成后将成为世界最大跨度的公铁两用斜拉桥。一旦大桥受损坍塌,不但导致交通受阻,更会对灾后救援工作产生极不利影响,因此,对该桥进行地震反应分析具有十分重要的意义。本论文借助有限元软件Midas Civil 2015,对沪通公铁两用长江大桥的抗震性能进行分析,主要研究内容包括:(1)建立了全桥空间有限元模型,对其自振特性进行了分析。(2)确定了反应谱参数,对大桥进行反应谱分析计算。分析了在四种荷载工况(纵向输入、横向输入、纵向+竖向输入、横向+竖向输入)作用下的结构响应,并着重讨论了反应谱进行长周期修正后对结构位移及内力的影响。(3)选取了三组适合场地特征的地震波(EL Centro波、Taft波及人工模拟地震波),对大桥进行一致地震时程分析,得到了结构在纵向+竖向输入、横向+竖向输入地震波作用下的地震响应,并与反应谱法得到的结果进行比较。(4)讨论了非一致地震激励下行波效应对结构地震响应的影响,得到了不同视波速下结构关键位置的位移及内力响应,并与一致时程的结果进行了比较。
[Abstract]:China is located between the two major seismic zones in the world. Due to the compression of the Pacific plate, the Indian plate and the Philippine sea plate, the seismic fault zone is well developed and the earthquake disaster is serious. As a part of traffic network, bridge plays an important role in lifeline seismic disaster prevention system. Compared with traditional bridges, long-span bridges have more investment, higher cost and more complex construction process. Therefore, the seismic requirements are also higher. Shanghai Stock Connect Bridge is a large span cable-stayed bridge which is under construction and is the crossing channel of China's coastal railway. The top six-lane highway is the Sitong Expressway, the maximum speed is 100 km/h, per hour, the lower four-lane railway is the Sujia Intercity Railway and the Shanghai Stock Connect Railway, the maximum speed is 200 km/h. per hour. The bridge is 2300 m in length and 1092 m in span. When completed, it will become the world's largest span of dual purpose cable-stayed bridge. Once the bridge is damaged and collapsed, it will not only cause traffic obstruction, but also have a very adverse impact on the rescue work after the disaster. Therefore, it is of great significance to analyze the seismic response of the bridge. With the help of the finite element software Midas Civil 2015, this paper analyzes the seismic behavior of the Shanghai-Stock Bridge, the main contents of which are as follows: (1) the spatial finite element model of the bridge is established. The natural vibration characteristics of the bridge are analyzed. (2) the parameters of the response spectrum are determined and the response spectrum of the bridge is calculated. The structural responses under four load conditions (longitudinal input, transverse input, longitudinal vertical input, transverse vertical input) are analyzed. The effects of long-period correction of response spectrum on the displacement and internal force of the structure are discussed. (3) three groups of seismic waves, (EL Centro wave, Taft wave and artificial simulated wave, are selected. The seismic response of the bridge subjected to vertical input and vertical input is obtained by means of uniform seismic time history analysis. And compared with the results obtained by response spectrum method. (4) the effect of traveling wave effect on structural seismic response under non-uniform earthquake excitation is discussed, and the displacement and internal force responses at different apparent wave velocities are obtained. The results are compared with the results of the same time course.
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U442.55;U448.27

【参考文献】