填充墙对于RC框架结构抗震性能的影响研究

发布时间：2018-10-25 20:25

【摘要】：带填充墙钢筋混凝土框架结构能够提供较大的使用空间,一直是我国多层房屋广泛采用的结构形式。传统设计中填充墙作为框架结构非受力构件,不承担水平荷载的作用,但历次震害研究表明,填充墙与框架是协同工作的。因此,我们不能简单的将填充墙看作非结构构件,应当考虑其与框架整体的协同作用。结合前人所做研究,本文主要完成的工作如下:(1)以某6层带填充墙框架结构为背景,根据刚度等效原则,采用等效斜撑模型来模拟填充墙,建立不同填充墙布置下的计算模型,通过模态分析将纯框架模型与填充墙框架模型进行对比,探讨现行规范对于框架结构周期折减系数的合理性。(2)采用振型分解反应谱法和时程分析法对填充墙框架结构进行了弹性和弹塑性分析。在多遇地震作用下,填充墙为结构提供了较大的侧向刚度,有效地减小了结构的侧向位移,承担了较大的水平剪力,起到了较好的耗能效果;在罕遇地震作用下,填充墙的刚度效应有所降低,但仍然能承担一部分水平剪力,对结构的位移起到一定的影响;填充墙的竖向不规则布置导致框架结构薄弱层的凸显,对抗震不利。(3)对纯框架模型和填充墙框架模型分别进行Pushover分析。通过梁、柱塑性铰的分布及发展程度可知,填充墙的加入有效的抑制了塑性铰的发展,但在未布置填充墙的楼层塑性铰发展迅速,加剧了薄弱层的破坏。通过对三种填充墙竖向不规则布置模型的性能点进行分析,得出了最不利的一种方案。(4)针对分析得出的填充墙最不利布置提出改进方案,建立相应的计算模型,通过非线性时程分析以及pushover分析等手段,围绕层间位移角、性能点和塑性铰等进行全面的有效性验证。(5)探究了不同填充墙材料对于框架结构抗震性能的影响。结果表明,在弹性分析下,轻质填充墙材料对结构位移的控制占有明显优势,对于填充墙竖向不规则布置的情况,轻质填充墙表现出较好的抗震性能;在罕遇地震作用下,由于传统砖墙的容重较大,使得结构吸收的地震作用较大,当填充墙发生破坏失效时,吸收的能量完全由原框架结构通过变形耗散,故传统砖墙对于框架结构的抗震更加不利,因此,选用轻质填充墙材料更加符合抗震设防的理念。
[Abstract]:Reinforced concrete frame structure with infilled walls can provide a large space for use and has been widely used in multi-story buildings in China. In the traditional design, the infilled wall, as a non-stress member of frame structure, does not bear the function of horizontal load, but previous earthquake damage studies show that the infilled wall and frame work together. Therefore, we can not simply regard the infilled wall as a non-structural component, we should consider its synergy with the whole frame. The main work of this paper is as follows: (1) based on the principle of stiffness equivalence, the infill wall is simulated by equivalent inclined brace model. The calculation model of different infill wall arrangement is established, and the pure frame model and the infilled wall frame model are compared by modal analysis. This paper discusses the rationality of the current codes for the periodic reduction coefficients of frame structures. (2) the elastic and elastoplastic analysis of infilled wall frame structures is carried out by using the mode decomposition response spectrum method and time-history analysis method. Under the action of frequent earthquakes, the infilled wall provides a large lateral stiffness for the structure, effectively reduces the lateral displacement of the structure, undertakes a large horizontal shear force, and plays a better energy dissipation effect. Under the rare earthquake, the stiffness effect of the infilled wall is reduced, but it can still bear some horizontal shear force, which has a certain effect on the displacement of the structure. The vertical irregular arrangement of infilled walls makes the weak story of frame structure prominent, which is unfavorable to earthquake resistance. (3) Pushover analysis of pure frame model and infilled wall frame model is carried out respectively. Through the distribution and development of plastic hinge in beam and column, it can be seen that the addition of infilled wall effectively inhibits the development of plastic hinge, but the plastic hinge of floor without infilled wall develops rapidly, which intensifies the failure of weak layer. By analyzing the performance points of three kinds of vertical irregular layout models of infilled walls, a most unfavorable scheme is obtained. (4) an improved scheme is put forward for the most unfavorable arrangement of infilled walls, and the corresponding calculation model is established. By means of nonlinear time-history analysis and pushover analysis, the effectiveness of different infilled wall materials on seismic behavior of frame structures is investigated by means of comprehensive validation of displacement angle, performance points and plastic hinges. The results show that, under the elastic analysis, the control of the structural displacement of the lightweight infilled wall has obvious advantages, and for the case of the vertical irregular arrangement of the filled wall, the lightweight infilled wall shows good seismic performance. Under rare earthquake, because of the large bulk density of traditional brick wall, the seismic action absorbed by the structure is greater. When the infilled wall fails, the absorbed energy is completely dissipated by the deformation of the original frame structure. Therefore, the traditional brick wall is more unfavorable to the earthquake resistance of the frame structure, so the choice of lightweight infilled wall materials is more in line with the idea of seismic fortification.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU352.11;TU375.4

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