隔震橡胶支座板式楼梯对框架结构抗震性能的影响分析

发布时间：2018-04-19 08:07

本文选题：抗震性能 + 滑移楼梯　；参考：《昆明理工大学》2017年硕士论文

【摘要】：楼梯间不仅是建筑中的竖向通道和紧急情况下的主要疏散通道,还是地震中唯一的逃生通道。然而,大量震害调查发现,地震引起的楼梯间破坏常常先于主体结构破坏,且破坏程度远远超过预期目标。相关分析表明,在地震波作用下,楼梯间的地震响应会在极短的时间内快速达到峰值。但通常在建筑结构设计中,总是把楼梯间分离出来单独考虑,把楼梯简化为仅承受竖向荷载的构件,把作用在楼梯上的荷载简单的等效到楼梯周边构件上,这样简化既未考虑地震作用对其的影响,也未考虑楼梯对主体结构的影响。因此,如何考虑楼梯对主体结构的影响,如何更科学合理的设计楼梯,使得楼梯在地震发生时真正成为安全的逃生通道,是本文要研究和解决的基本问题。对于最常用的钢筋混凝土框架结构,如果平台梁与框架柱现浇在一起,容易使框架柱形成短柱,而导致脆性破坏。本文为了避免此种做法带来的不利因素,采取对楼梯间单独设置梯柱的方法,分析楼梯对框架主体结构的影响。本文主要研究楼梯对框架主体结构抗震性能的影响,以及如何避免楼梯在罕遇地震作用下先于主体结构破坏。本文的主要研究工作如下:1、系统地学习和梳理了国内外楼梯对框架结构抗震性能影响的研究论文,分析总结了所取得的主要成果与不足之处。2、对无楼梯的纯框架结构、有楼梯的框架-楼梯体系以及滑移楼梯和隔震橡胶支座楼梯进行模态分析、反应谱分析和弹性时程分析,分析表明:楼梯增强了主体结构的.刚度,且沿梯板方向增加的刚度大于垂直于梯板方向。梯段板下端采取弱连接对主体结构的影响程度较小,楼梯本身的受力情况也得到了一定的改善,但楼梯对结构的影响仍不容忽略。3、改变梯柱截面尺寸进行分析,发现梯柱截面尺寸越小,楼梯对框架整体结构角柱以及楼梯周边构件的影响越小,框架-楼梯体系的受力特性越接近无楼梯的纯框架结构。但楼梯刚度越大,梯柱分担的剪力越多。4、对框架-楼梯体系进行罕遇地震作用下的Push-over分析,得到罕遇地震下的基底剪力-位移曲线、塑性铰的发展情况、分布范围以及整体结构和楼梯构件的屈服机制;对滑移楼梯和隔震橡胶支座楼梯进行罕遇地震作用下的动力弹塑性分析,分析结果表明:塑性铰主要分布在底部三层,且沿楼梯周边集中分布,隔震橡胶支座楼梯即使在罕遇地震作用下,也不会出现类似于滑移楼梯的梯段板下端翘起或脱落的情况,楼梯不会先于主体结构破坏,可实现楼梯间作为地震时的“逃生通道”。
[Abstract]:Stairwell is not only the vertical passage in the building and the main evacuation passage in emergency, but also the only escape way in earthquake.However, a large number of earthquake damage investigation found that the damage of stairwell caused by earthquake often preceded the main structure damage, and the damage degree far exceeded the expected target.The correlation analysis shows that the seismic response between stairs can reach the peak in a very short time under the action of seismic wave.But usually in the design of the building structure, the stairwell is always considered separately, the staircase is simplified as the member that only bears vertical load, and the load acting on the staircase is simply equivalent to the surrounding member of the staircase.This simplification does not take into account the influence of seismic action or staircase on the main structure.Therefore, how to consider the influence of staircase on the main structure, how to design the staircase more scientifically and reasonably, and how to make the staircase become the safe escape way when the earthquake occurs, is the basic problem to be studied and solved in this paper.For the most commonly used reinforced concrete frame structure, if the platform beam and the frame column are cast-in-situ together, it is easy to make the frame column form a short column, which leads to brittle failure.In order to avoid the disadvantageous factors brought about by this method, this paper analyzes the influence of staircase on the main structure of frame by using the method of separate stair column in the stairway.This paper mainly studies the influence of staircase on the seismic behavior of frame structure and how to avoid the damage of staircase before the main structure under rare earthquake.The main research work of this paper is as follows: 1. The paper systematically studies and combs the influence of staircase at home and abroad on the seismic performance of frame structure, and analyzes and summarizes the main achievements and shortcomings.The frame-staircase system with staircase, sliding staircase and rubber isolation support staircase are analyzed by modal analysis, response spectrum analysis and elastic time history analysis. The analysis shows that the stair strengthens the main structure.Stiffness, and the increase along the direction of the ladder plate stiffness is greater than vertical to the direction of the ladder plate.The influence of weak connection at the lower end of the ladder plate on the main structure is relatively small, and the stress situation of the staircase itself has been improved to some extent, but the influence of the staircase on the structure should not be ignored. The influence of the staircase on the structure can not be ignored. The change of the section size of the ladder column is analyzed.It is found that the smaller the section size of the ladder column, the less the influence of staircase on the corner column of the frame structure and the surrounding members of the staircase, and the force characteristics of the frame-staircase system are closer to the pure frame structure without the staircase.However, the greater the stiffness of staircase, the more shearing force the ladder column shares. The Push-over analysis of frame-staircase system under rare earthquake is carried out, and the base shear displacement curve and the development of plastic hinge under rare earthquake are obtained.The distribution range, the yield mechanism of the whole structure and the stair members, the dynamic elastic-plastic analysis of sliding staircase and rubber bearing staircase under rare earthquake, the results show that the plastic hinge is mainly distributed in the bottom three floors.And concentrated distribution along the periphery of the staircase, even under the rare earthquake, the rubber bearing staircase will not appear similar to the slip staircase, the lower end of the ladder board will not be damaged before the main structure.The stairwell can be used as an escape way during an earthquake.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU352.11;TU375.4

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