在役曲线梁桥抗震性能评估

发布时间：2018-01-09 02:06

本文关键词：在役曲线梁桥抗震性能评估　出处：《山东建筑大学》2017年硕士论文　论文类型：学位论文

【摘要】：曲线梁桥因其使用功能及外形美观而被广泛应用于城市立交桥中。一些桥梁因服役年限较长,已经不能满足现阶段的抗震要求,需要对其进行抗震性能评估。本文以一座半径为55m的三跨在役曲线连续梁桥为研究对象,分别分析桥梁在低频地震动及高频地震动作用下的地震响应,选取合适的地震损伤模型对桥梁各构件及整体结构进行损伤分析,并基于桥梁检测结果引入承载能力检算系数Z1对桥梁各构件损伤指数进行修正,同时对桥梁各构件及整体结构进行抗震性能评估,具体研究成果如下:(1)除在高频地震动对应的小震作用下,主梁不发生碰撞外,在其他各强度地震动作用下,主梁均发生了不同程度的碰撞损伤,其中在低频地震动对应的大震作用下,主梁出现轻微破坏。其他情况下,主梁虽与相邻联主梁或挡块之间发生了碰撞,但是主梁依然处于基本完好状态。(2)除在高频地震动对应的小震作用下,支座均处于基本完好状态外,在其他各强度地震动作用下,支座均发生了不同程度的破坏,其中在低频地震动对应的大震作用下,支座破坏最为严重,部分支座已经完全破坏。对比各地震动作用下支座的破坏程度知道,在低频地震动作用下,支座破坏程度较高频地震动作用下更为严重。(3)除在高频地震动对应的小震作用下,各桥墩破坏较轻微外,在其他各强度地震动作用下,桥墩发生了较为严重的破坏,其中在低频地震动对应的大震作用下,各桥墩均已完全破坏,桥梁发生倒塌。在其他情况下,桥墩发生了中等破坏或严重破坏。(4)对比各地震动作用下该曲线梁桥的破坏程度知道,在低频地震动作用下,桥梁结构破坏程度较高频地震动作用下桥梁结构破坏更为严重。另外各地震动随强度的增加,桥梁结构地震响应更为显著,破坏程度加剧。(5)桥梁结构的破坏是各构件累积损伤破坏的结果,任何构件发生损伤均会对整体结构的安全性造成影响,而支座及墩柱的损伤对桥梁整体结构的损伤破坏影响较大,其中桥墩的损伤状况又会对桥梁整体结构的损伤程度起决定性作用。(6)通过引入检算系数Z1对桥梁各构件损伤指数进行修正,可以使桥梁损伤情况及抗震性能评估结果更符合实际。
[Abstract]:The curved girder bridge due to its function and appearance have been widely used in the city overpass. Some bridges for longer service life, has been unable to meet the requirements of seismic design at the present stage, the need for seismic performance evaluation on it. This paper takes a radius of three 55m in the battle of Qu Xianlian cross continuous girder bridge as the research object, in the seismic analysis of bridge are low frequency and high frequency ground motion under the action of earthquake response, selection of seismic damage model suitable for damage analysis of bridge components and the overall structure of the bridge, and based on the test results into the bearing capacity checking coefficient Z1 of each bridge component damage index is modified, and to evaluate the seismic performance of bridge components and the overall structure, the specific research results are as follows: (1) in addition to a small earthquake in the corresponding vibration frequency, the no collision, in other intensity of ground motion under the action of main girder There were different degree of collision damage, the big earthquake in the low-frequency ground motion corresponding to the main girder, slight damage. In other cases, although with the adjacent beam or girder joint block collision happened between blocks, but is still in the main girder is basically in good condition. (2) in addition to the small earthquake corresponding vibration in high frequency under the support, are basically in good condition, in the other the intensity of ground motion under the action of bearing occurred in different degrees of damage, the big earthquake in the low-frequency ground motion corresponding to the bearing, the most serious damage part of the bearing has been completely destroyed. Damage degree of bearing vibration effect contrast around the know in the low frequency, seismic damage, bearing high degree of seismic frequency is more serious. (3) in addition to a small earthquake in the corresponding vibration frequency, each pier was destroyed slightly, the other in the intensity of earthquake action Under the severe damage of pier, large earthquake in the low-frequency ground motion corresponding to each pier, has been completely destroyed, the bridge collapsed. In other cases, the occurrence of secondary damage or serious damage to the pier. (4) the extent of the damage of the curved girder bridge under seismic effect contrast around the know in the low frequency, seismic, bridge structure damage degree of high frequency vibration damage of bridge structure under the action of more serious. Also around the vibration with the increase of the strength of the seismic response of bridge structures is more significant, the extent of damage increased. (5) the bridge structure damage is the component damage accumulation of the results of any member the damage will be affected the safety of the whole structure of the support and the damage to the pier and the whole bridge structure damage influence, the damage of bridge pier and on the whole structure of the bridge damage Degree plays a decisive role. (6) by introducing the checking coefficient Z1, we can modify the damage index of each component of bridge, so that the evaluation results of bridge damage and seismic performance are more consistent with reality.

【学位授予单位】：山东建筑大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U442.55

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