强地震区深水大跨度斜拉桥的地震响应分析

发布时间：2018-02-28 20:14

本文关键词： 动水压力 Morison方程简化辐射波浪法混合法地震波合成地震响应　出处：《西南交通大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着我国基础建设新时代的到来,交通建设将会面临特殊地形条件,特别是桥梁所占的比例很大,不可避免将会遇到跨江,跨海以及跨水库的桥梁,这些地区建设桥梁将会面临一个共同的特点,深水墩桥梁的建设。而桥梁在运营阶段必需考虑偶然荷载地震作用对桥梁的的影响,地震对深水桥梁作用时,桥墩会发生刚体运动和弹性振动,从而影响桥墩周围水体的运动,水体的运动又会以动水压力的形式反作用于桥墩,两者相互影响,就是复杂的墩水耦合问题。正是由于墩水耦合的影响,会产生不同于在空气中桥梁的动力特性和地震响应,可能会对桥梁结构产生不利的影响,因此研究动水压力的简化方法及其对桥梁的响应是本文的重点。本文以某大跨度公铁两用斜拉桥为工程实例,对其进行动水压力分析。具体包括以下几个方面：(1)通过大量的文献资料介绍了地震及其桥梁结构的震害特点,进而说明深水墩桥梁的抗震及其国内外研究现状。(2)阐述了动水压力在工程中常用的计算方法及其基本理论,包含Morison方程、辐射波浪法和流体单元法。(3)详细的介绍了能够同时考虑矩形空心墩外域水和内域水的动水压力的计算方法：基于欧洲桥梁抗震规范同时考虑内外域水体的扩展Morison方程；基于辐射波浪法的简化公式；基于辐射波浪法和流体单元法的混合法。结合某大跨度公铁两用斜拉桥的矩形空心墩讨论其内外域水动水压力附加质量相对于墩身的分布特点,并进行了方法间的对比。(4)分析了动水压力对桥梁结构动力特性的影响。(5)考虑地震动空间效应(场地效应、行波效应、相干效应)的地震波的合成,对深水墩大跨斜拉桥进行一致激励和考虑空间效应多点激励的地震响应分析,并用动水压力影响系数判断地震动水压力对桥梁的影响大小。
[Abstract]:With the arrival of a new era of infrastructure construction in China, traffic construction will face special terrain conditions, especially the large proportion of bridges, which will inevitably meet bridges across rivers, seas and reservoirs. The bridge construction in these areas will be faced with a common characteristic, the construction of deep water pier bridge, and the bridge must consider the influence of accidental load and earthquake on the bridge in the operation stage, when the earthquake acts on the deep water bridge, Rigid body motion and elastic vibration will occur on the pier, which will affect the movement of the water body around the pier, and the movement of the water body will react to the pier in the form of dynamic water pressure. It is precisely because of the influence of pier-water coupling that the dynamic characteristics and seismic responses of bridges in the air will be different from those of bridges in the air, which may have a negative impact on the bridge structure. Therefore, the emphasis of this paper is to study the simplified method of hydrodynamic pressure and its response to bridges. The characteristics of earthquake and its bridge structure are introduced through a large amount of literature data, including the following aspects: 1. Furthermore, the paper explains the aseismic behavior of deep water pier bridge and its research status at home and abroad. (2) the calculation method and basic theory of dynamic water pressure in engineering, including Morison equation, are expounded. Radiation wave method and fluid element method. (3) the calculation method of dynamic water pressure which can simultaneously consider the external and inner water of rectangular hollow pier is introduced in detail. Based on the seismic code of European bridges, the extended Morison equation of inner and outer water body is considered simultaneously. Based on the simplified formula of radiation wave method, the hybrid method based on radiation wave method and fluid element method, the distribution characteristics of hydrodynamic hydrodynamic pressure and additional mass relative to the pier are discussed in combination with the rectangular hollow piers of a large-span double-purpose cable-stayed bridge. The influence of hydrodynamic pressure on the dynamic characteristics of bridge structure is analyzed. (5) the seismic wave synthesis considering the spatial effect of ground motion (site effect, traveling wave effect, coherent effect) is analyzed. The seismic response analysis of long-span cable-stayed bridge with deep water piers under uniform excitation and multi-point excitation considering spatial effect is carried out. The influence coefficient of dynamic water pressure is used to judge the influence of ground motion water pressure on bridge.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U442.55;U448.27

【参考文献】