【作者】 陈福军；

【导师】 赵灿晖；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2010， 硕士

【摘要】 桥梁做为公路交通网络的重要组成部分,是公路系统的咽喉。就整个公路交通网络而言,桥梁无论跨度大小,只要在地震中发生严重损毁,都有可能导致交通网络的瘫痪,从而严重影响灾后抗震救灾工作,汶川地震即是一个鲜明的实例。简支体系桥梁作为中小跨度桥梁最广泛采用的桥型,针对其进行专门的抗震设计研究具有重要的现实意义。本文在收集近年来国内外多次大地震震害的基础上,总结了简支体系桥梁的主要震害类型,并对主要震害特点及机理进行了简要分析,得到了震害启示；在此基础上,对简支体系桥梁基于桥墩保护和横向落梁保护的概念设计原则进行了研究。1)收集了近年来国内外10次大地震中120座简支体系桥梁的主要震害现象,归纳出简支体系桥梁的支承破坏或落梁、桥墩震害、地基震害为主要震害；桥台震害、伸缩缝或桥面连续震害、主梁结构性震害为次要震害；对简支体系桥梁的主要震害特点及机理进行了简要分析,得到了震害启示。2)运用梁格法建立了某桥面连续预应力混凝土简支梁桥动力计算模型,进行了简支梁桥地震响应特性分析,总结了简支体系桥梁的地震响应特性。3)通过探讨桥面连续的作用及联孔长度、支座优化布置(桥墩组合抗推刚度)、孔跨布置等方面进行了地震作用下桥墩内力分析,得到了桥面连续简支体系桥梁基于桥墩保护的概念设计原则。核心问题是应使得一联内各墩内力分配大致均衡,从而避免结构出现薄弱环节,发挥出结构的整体抗震性能；同时给出了已知桥墩尺寸时,支座的合理选型方法。4)通过探讨挡块刚度对结构横向地震响应的影响,总结了挡块的合理设置原则。确定挡块刚度的基本原则应是在确保主梁不发生落梁的前提下,尽量减小桥墩内力。更多还原

【Abstract】 Bridge is the throat of road system, which is an important part of road traffic network. No matter how long brige is, once bridge is damaged, there would be a Paralysis in road traffic network, wenchuan earthquake is a clear example in which the damage of bridge had once affected the relief work seriously. As simply-support system bridge is the most widely used brige shape of the medium or small-span bridge, the special seismic design research of it has an important practical significance. Based on the collections of seismic damage in recent earthquakes, this article summarized the main seismic damage of simply-support system bridge, simply analyzed the main characteristics and mechanism of seismic damage, summarized the experience, and then researched the conceptual design principle, which is based on the protection of piers and protection of horizontal falling beam in simply-support system bridge.1) The data of main seismic damage of 120 simply-support system bridges was Collected in recent 10 times domestic and aborad earthquakes, the article genaeralized the conclusion that bearing damage or falling beams and the seismic damage of bridge piers and foundations are main seismic damage, the damages of abutment and expansion joint and continuous deck and structural seismic damage of main beams are subordinate seismic damage, we analyzed the mechanism of seismic damage of simply-support system bridge simply and obtained the enlightenment of seismic damage.2) The dynamic model of some pre-stressed concrete continuous deck simply supported T-beam bridges with the grillage method was established then we analyzed and summarized the earthquake response properties of simply supported bridge.3) According to analyzing the effect of the length of united spans, the effect of continuous deck, the optimal layout of supports(composed anti-push stiffness of bridge piers), the layout of spans, we analyzed the internal force of bridge piers, obtained the conceptual design principle of continuous deck simply-support system bridge based on protection of bridge piers. The core problem is that it should be balanced to the composed anti-push stiffness of each pier in one union so as to avoid appearing weak link of the structure and play the overall seismic performance of the structure, meanwhile we gived the reasonable method of selecting bearings when the size of bridge pier is known.4) By means of probing the effect of block stiffness to horizontal structual earthquake response, the article summarize the reasonable installing principle of block. The basic principle of defining block stiffness is not overly increasing the internal forces of bridge under the premise of ensuring not falling main beams.更多还原