高墩大跨度曲线连续刚桥优化设计及其地震响应时程分析-防灾减灾工程及防护工程专业论文.docxVIP

摘要 摘要 高墩大跨度曲线连续刚构桥是随着我国高速公路向山区发展开始出现的。近 年来随着修建跨度的增大、桥墩的增高、曲率的减小，大跨高墩曲线连续刚构桥 应用范围更广泛，必将给山区道路选线增加更大的自由度，有着广阔的发展前景。 本文以贵州沙银沟大桥为依托工程，采用空间梁单元建立原设计方案的参数 化模型，主要完成了全桥的优化设计、模态分析和地震动时程响应分析等工作。 建立了多个模型分析优化设计和桩土相互作用对桥梁结构的自振特性和地震响应 的影响，得出了一些合理的结论。主要研究内容可以归结为： 1．根据原设计方案，以截面基本尺寸为设计变量，以挠度和应力作为约束条件， 建立以全桥造价最优为目标函数的参数化设计模型。 2．采用桥梁三维预应力分析系统软件BridgeKF，初步研究了横竖向预应力对高 墩大跨度曲线连续刚构桥受力的影响，并在此基础上提出了横竖向预应力的优 化方法。 3． 考虑优化前后和桩土相互作用的影响，建立四种模型分别进行模态分析并做比 较。 4．考虑两种地震动输入模式进行比较分析，得出一些合理的结论。 5．分别对四种模型进行地震动反应时程分析，给出了优化设计前后的位移和内力 包络图，并分析了桩土相互作用对桥梁地震响应的影响。 通过以上工作希望能对活性粉末混凝土材料应用于高墩大跨度曲线连续钢构 桥有所帮助，同时对这类桥型的抗震设计提供一定的参考。 关键词：高墩大跨曲线连续刚构桥；优化设计；模态分析；地震响应；时程分析  北京交通人学硕七论文 Abstract In our country,along with high way extends into mountainous area蛳gh_pier long-span prestressed concrete and consecutive rigid curved beam bridge began to appear．In recent years，with the construction of the span increasing the pier heightelling and the decreasing of curvature，this kind of bridge will have a broad scope of application，which is bound to make the path route selection more uncontrolled，and it will have a wide prospect for development． This thesis relies on the engineering of Guizhou Shayingou Bridge，and 3-D Linear Finite Strain Beam was used to model the original parametric design．Optimization of Shayingou Bridge modal analysis and seismic response time—history analysis constitute the whole paper．Several models was established to research modal and dynamic time—history analysis under the influence of optimization and pile-soil interaction，and drew some reasonable conclusions．Main research Can be summarized as follows： 1．According to the original design，taking sectional dimensions of the box-girder as design variables，under constraints of strength and deflection，while price of the whole bridge as objective function，parametric design model Was established． 2．Hi帅ier long-span prestressed concrete and consecutive rigid curved beam bridge under the influence of lateral and vertical prestressing tendon Was preliminarily studied b