基于中美规范设计的连续刚构桥地震易损性研究

发布时间：2018-06-22 09:41

本文选题：连续刚构桥 + 中美抗震规范　；参考：《长沙理工大学》2015年硕士论文

【摘要】：地震作为一种随机性大破坏能力强的自然灾害,桥梁这一生命线工程在抗震救灾过程中扮演着重要的角色。在公路桥梁抗震领域,各国根据不同的自然条件、使用要求制定出不同了的抗震设计规范。随着我国路桥交通网络的迅猛发展,连续刚构桥因其具有跨度大、平顺性好、适应性强、受力合理等优点,已经成为跨越深沟险壑的首选桥型。连续刚构桥也在向高墩与大跨发展,但其抗震设计相对于其实际应用相对滞后。桥梁地震易损性曲线作为表达桥梁结构损伤概率与地面运动强度之间关系的最有效的手段之一,对震后的经济损失与结构性能的评估及工程检修都有重要意义。因此开展该类桥梁结构抗震设计与地震易损性方面的研究,对保障该类桥梁的抗震安全具有重要意义。本文通过98m+180m+98m大跨径预应力混凝土双薄壁墩连续刚构桥工程,采用我国现行的公路桥梁抗震设计细则(JTG/T B02-01-2008)和美国公路桥梁抗震设计规范(AASHTO Guide Specifications for LRFD Seismic Bridge Design 2011)分别进行抗震设计,并建立模型采用非线性时程分析的方法对工程实例进行了桥梁地震易损性分析,进而对分析结果对比研究,以此希望能为我国的连续刚构桥的抗震设计提供一些借鉴。本文主要做了以下几部分工作:(1)查阅大量国内外资料与文献的基础上,归纳总结了桥梁抗震设计中常用的抗震设计理念以及桥梁地震易损性的相关研究成果,介绍了地震易损性分析原理,并总结了地震易损性曲线的构建方法。(2)归纳总结两种抗震规范理论上的异同,并通过郧县沧浪洲汉江大桥运用动力时程分析方法分别进行了两种规范下的设计计算,并对其进行对比研究。(3)基于Midas-Civil桥梁结构分析软件,对上述计算结果分别建立了全桥三维数值模型,模型中采用弹塑性纤维单元模拟桥墩。通过非线性时程分析方法模拟桥例在40条天然地震波调幅后的地震响应,并对两个模型中的各关键截面进行了地震易损性分析。(4)通过二者的易损性曲线不难发现,基于《AASHTO》所设计的连续刚构桥在各破坏状态的超越概率均低于基于《08细则》所设计的,其原因在于《AASHTO》通过延性构件构造要求对墩柱中延性构件构造进行了较为详尽的规定,使其延性得到了较好地发挥。
[Abstract]:As a kind of natural disaster with strong random and great damage, bridge, a lifeline project, plays an important role in the process of earthquake relief. In the field of highway and bridge seismic design, according to different natural conditions and requirements, different seismic design specifications are formulated. With the rapid development of road and bridge traffic network in China, continuous rigid frame bridge has become the preferred bridge type for crossing deep gully because of its advantages of large span, good ride comfort, strong adaptability and reasonable force. Continuous rigid frame bridges are also developing towards high piers and long spans, but their seismic design is lagging behind their practical application. As one of the most effective means to express the relationship between the damage probability and the ground motion intensity, the seismic vulnerability curve of the bridge is of great significance to the evaluation of the economic loss, the performance of the structure after the earthquake and the engineering overhaul. Therefore, it is of great significance to study the seismic design and seismic vulnerability of this kind of bridge structure in order to ensure the seismic safety of this kind of bridge. In this paper, through 98m 180m 98m long span prestressed concrete double thin-walled pier continuous rigid frame bridge project, The aseismic design of highway bridges in China (JTG / T B02-01-2008) and AASHTO Guide specifications for LRFD Seismic Bridge Design 2011 is adopted. The model is established and the nonlinear time-history analysis method is used to analyze the seismic vulnerability of bridges in engineering cases. The results of the analysis are compared and studied in the hope that it can provide some reference for the seismic design of continuous rigid frame bridges in China. The main work of this paper is as follows: (1) on the basis of consulting a large number of domestic and foreign materials and literature, this paper summarizes the commonly used aseismic design ideas in bridge seismic design and the related research results of bridge seismic vulnerability. The principle of seismic vulnerability analysis is introduced, and the method of constructing seismic vulnerability curve is summarized. (2) the similarities and differences between the two seismic codes are summarized. Through the use of dynamic time-history analysis method, the design and calculation of Yunxian Canglangzhou Hanjiang Bridge are carried out respectively under two specifications. (3) based on MidCivil Civil bridge structure analysis software, The three dimensional numerical model of the whole bridge is established, in which the elastoplastic fiber element is used to simulate the pier. The nonlinear time-history analysis method is used to simulate the seismic response of the bridge after 40 natural seismic waves are amplitude modulated, and the seismic vulnerability of each key section of the two models is analyzed. (4) it is not difficult to find out the vulnerability curves of the two models. The transcendental probability of the continuous rigid frame bridge designed on the basis of < AASHTO > is lower than that of the one based on < 08 rule >. The reason is that < AASHTO > specifies the ductile component construction in the pier column through the ductile component construction requirement. So that the ductility of the better play.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U442.55;U448.23

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