基础隔震掉层框架结构设计若干问题研究

发布时间：2018-01-03 17:22

本文关键词：基础隔震掉层框架结构设计若干问题研究　出处：《重庆大学》2016年硕士论文　论文类型：学位论文

【摘要】：掉层框架结构能够充分利用山地地形,其抗震性能与普通框架结构有较大区别。有丰富的工程实践证明,基础隔震技术能有效的减轻地震灾害。将基础隔震与掉层框架结构相结合不失为一种有效的减轻震害的途径。但目前尚未开展基础隔震掉层框架结构设计的系统研究。本文以掉层平面框架为研究对象,对基础隔震掉层框架结构设计的若干关键问题进行研究,主要开展了以下几个方面的工作:(1)探讨了现有基础隔震分析及设计方法在掉层框架结构中的适用性问题,分析结果表明强制解耦的振型分解反应谱法是一种计算比较简便且精度满足要求的分析方法,现有的水平减震系数的取值与隔震设计方法对于基础隔震掉层框架结构均不适用。(2)给出了基于基底剪力比的基础隔震掉层框架结构的水平减震系数。对于掉层框架结构可以将隔震结构与非隔震结构上下接地处基底剪力之和的比值作为作为新的水平减震系数去评价减震效果。通过对基础隔震单层单跨与多层多跨掉层框架结构的分析,可知将基底剪力比作为水平减震系数来评价隔震结构的减震效果具有较好的适用性。(3)给出了基于水平减震系数的隔震层简化设计方法。首先推导出了结构考虑高阶振型影响的基底剪力的理论公式。然后采用等效总重力荷载系数来近似考虑高阶振型的影响,运用参数分析方法,研究了非隔震掉层框架结构等效总重力荷载系数的取值范围。对基础隔震掉层框架结构进行参数分析,分析结果表明在简化计算时可以把基础隔震掉层框架结构等效为单质点体系进行基底剪力的求解。在以上分析的基础上给出了基于水平减震系数的隔震层的简化设计方法。(4)提出了基础隔震掉层框架结构的分部分阶段设计方法。根据基础隔震掉层框架的特点提出分部设计思路,按非隔震固端模型进行上接地柱及以上各层(简称上部楼层)的设计,按非隔震上接地滑动模型(简称滑动模型)进行上接地层非接地柱及掉层部分(简称下部楼层)设计。建立了上部楼层最大层间剪力比与水平减震系数的关系、下部楼层最大层间剪力比与水平减震系数的关系以简化隔震层以上结构设计。提出了适合于基础隔震掉层框架结构的分部分阶段隔震设计方法,通过设计算例表明:该方法简单实用,适合推广应用。
[Abstract]:Falling floor frame structure can make full use of mountainous terrain, its seismic performance is different from that of common frame structure, which has been proved by engineering practice. Foundation isolation technology can effectively reduce earthquake disaster. It is an effective way to reduce earthquake damage by combining foundation isolation with falling floor frame structure. But at present, there is no system for the design of foundation isolation floor frame structure. This paper takes the falling plane frame as the research object. In this paper, some key problems in the design of base isolated floor frame structure are studied. The main work of this paper is as follows: 1) the applicability of the existing foundation isolation analysis and design method in the falling floor frame structure is discussed. The analysis results show that the forced decoupling mode decomposition response spectrum method is a simple and accurate analysis method. The existing horizontal damping coefficient and isolation design method are not suitable for the base isolated floor frame structure. In this paper, the horizontal damping coefficient of base-isolated frame structure based on the ratio of base shear force is given. The ratio of the sum of the base shear force between the isolated structure and the non-isolated structure can be regarded as a new method for the falling floor frame structure. The horizontal damping coefficient is used to evaluate the effect of seismic absorption. The analysis of single-story single-span frame structure and multi-story multi-span frame structure is carried out. It can be seen that the base shear ratio as the horizontal damping coefficient to evaluate the seismic absorption effect of isolated structures has a good applicability. A simplified design method of isolation layer based on horizontal damping coefficient is presented. Firstly, the theoretical formula of base shear force considering the influence of higher vibration modes is derived, and then the equivalent total gravity load coefficient is used to approximate consider high-order vibration. Type A effect. The parameter analysis method is used to study the range of the equivalent total gravity load coefficient of the frame structure with non-isolation floor. The parameter analysis of the frame structure with the base isolation floor is carried out. The analysis results show that the foundation isolated floor frame structure can be equivalent to a single mass system when the calculation is simplified and the base shear force can be solved. Based on the above analysis, the simplified isolation layer based on horizontal damping coefficient is given. Design method. 4) the design method of the frame structure with isolation floor is presented. According to the characteristics of the floor frame, the design ideas of each part are put forward. The design of the upper earthing column and the above layers (referred to as the upper floor) is carried out according to the model of non-isolating fixed end. According to the non-isolated ground sliding model (referred to as the sliding model), the ungrounded column and the falling part of the upper ground layer (the lower floor) are designed, and the relationship between the maximum interstory shear ratio of the upper floor and the horizontal damping coefficient is established. The relationship between the maximum interstory shear ratio of the lower floor and the horizontal damping coefficient is used to simplify the design of the structure above the isolation floor. A partial isolation design method suitable for the frame structure with the base isolation falling floor is proposed. The design example shows that the method is simple and practical and suitable for popularization and application.
【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TU352.12

【相似文献】