【作者】 杨彦波；

【导师】 胡兆同；

【作者基本信息】 长安大学 ， 桥梁与隧道工程， 2010， 硕士

【摘要】 随着我国桥梁事业的发展,国内大型桥梁数量快速增加,桥梁体系也在悄然发生着变革：跨度更大,桥墩更高,整体刚度更小,造型更加美观。相应的也引出了新的课题：结构自振周期更大,地震响应更加强烈,抗震措施更加复杂。另外我国的地震活动较多而且强烈,几乎占世界大陆地震总量的三分之一。不久前的汶川地震,产生的地震波含有丰富的长周期成分,对已建的大跨度桥梁造成了较大的危害,同时也暴露出许多问题,大跨度桥梁在长周期地震中的抗震问题就显得日趋严峻。鉴于此,本文以大跨连续刚构桥为研究对象,进行以下几个方面的研究：(1)针对研究内容分别建立六种空间有限元模型,进行各种模型结构自振特性分析；(2)针对长周期地震波的特点,对模型输入含有较多长周期成分的地震波进行动力时程分析,并与输入普通地震波的动力时程分析进行对比；(3)对结构进行桩—土—结构相互效应和行波效应的影响分析；(4)改变大跨连续刚构桥的桥墩高度,对不同模型输入含有较多长周期成分的地震波进行动力时程分析,并与对应模型输入普通地震波的动力时程分析进行对比。通过上述分析得到一些结论,如下：(1)大跨连续刚构桥在长周期成分较多的地震波作用下,横桥向内力和位移响应大大增加；(2)考虑桩—土—结构相互效应后,结构的基频降低,自振周期延长,在地震作用下结构各部分位移增大,主梁内力也有一定增大；(3)考虑行波效应,结构内力和位移变化较大,有增有减,局部位置峰值增大；(4)调整大跨连续刚构桥的桥墩高度,随着墩高的降低,结构自振周期减小,长周期地震波对结构局部响应的增大效果逐渐减小。通过上述内容的分析希望对同类型结构的抗震设计和研究工作提供一定的帮助和参考。更多还原

【Abstract】 Along with the development of our country bridges, a rapid increase in the number of domestic large-scale bridges, bridge systems are quietly undergoing changes:a greater span, pier higher, the overall stiffness of smaller, more beautiful shape. Accordingly leads to a new topic:structural natural periods greater, more intense seismic response, seismic measures more complex. In addition our country large and strong seismic activity, accounting for almost one-third of the world’s total continental earthquakes. Recent Wenchuan earthquake in China, seismic waves were comparatively rich long-period components that have been built long-span bridges caused major damage, and also exposed many problems, long-span bridges in the long-period earthquakes in the seismic problem is increasingly difficult. In view of this, this paper span continuous rigid frame bridge as the research object for the following areas of study:(1)establish for the content of the six space of finite element model,and do analysis various vibration characteristics of model structure;(2) for long-period seismic wave characteristics, do input the model contains more long-period components of seismic wave dynamic analysis, and input common period seismic waves in the dynamic analysis were compared;(3)do the structure of the pile-soil-structure interaction effect analysis and traveling wave effect analysis;(4) change the pier height parameters, for different input of the model contains more long-period components of seismic wave dynamic analysis, and with the corresponding period of input seismic waves of ordinary dynamic analysis were compared.Through the above analysis, some conclusions are drawn, as follows:(1)span continuous rigid frame bridge components in more long-period seismic waves, transverse to the internal force and displacement response of greatly increased;(2) considering pile-soil-structure interaction, the structure of the fundamental frequency decreases, extend the natural cycle, displacement of the structures increases,and also the main beams internal forces; (3)considering wave effects, internal force and displacement have large changes,in particular large increases in local peak;(4) adjusting span continuous rigid frame bridge pier height parameters, with the height of piers and the reduction of structural natural periods decrease, long-period seismic waves on the structure of the local response to the increasing effect of decreases.Hope that through the above analysis of the structure of the same type of seismic design and research will provide some help and reference.更多还原