砌体结构教学楼抗震性能及地震破坏机制控制研究

发布时间：2018-03-25 15:35

本文选题：砌体结构　切入点：震害分析　出处：《西南交通大学》2013年博士论文

【摘要】：2008年汶川大地震造成砖砌体结构教学楼大量破坏,部分教学楼受到严重破坏甚至倒塌,砌体结构教学楼在强震作用下的抗震性能和抗倒塌安全性引起学者们的广泛关注。砌体结构教学楼一般具有开间和进深较大、墙体数量少、纵墙开洞率高等不利于结构抗震的特点,目前对其抗震性能的认识主要基于震害调查分析,现行抗震设计规范针对大开间砌体结构的地震破坏模式设计缺少特别规定,对砌体结构教学楼的抗震性能、地震破坏机制控制以及窗间墙和进深较大墙体的抗震性能及其影响因素等研究不够。本文选取砌体结构教学楼为研究对象,对大开间砌体结构的抗震性能及地震破坏机制控制进行研究,主要研究工作和结论如下： 1)分析了砌体结构教学楼的组成特点和典型震害特征,比较了砌体结构“强柱弱梁”和“强梁弱柱”两种宏观破坏机制下结构抗震能力的差异,对结构震害原因进行了初步分析,针对结构抗震的薄弱环节提出了相关的抗震设计建议。 2)进行了5片纵墙试件的拟静力试验,研究了窗间墙的抗震性能及其影响因素。结果表明,按照规范要求设置构造柱的墙体具有较好的抗震能力,适当增大构造柱截面尺寸能够进一步改善墙体的破坏形态、延性和耗能能力,但增大中柱截面配筋率到一定程度时反而降低墙体的延性和耗能能力。 3)进行了5片横墙试件的拟静力试验,分析了圈梁与构造柱的布置方式对其破坏模式和抗震性能的影响。结果表明,圈梁与构造柱的设置方式决定了墙体的抗震性能,按照现行抗震设计规范在横墙两端设置构造柱,同时保证墙体与基础梁间不发生剪切滑移,则横墙的抗震性能相对较好；中间增设构造柱或同时加设圈梁墙体的抗震性能并没有得到有效改善,但增设圈梁和构造柱的试件,极限变形后破坏墙块的变形受到中间圈梁的约束,墙体具有较好的后期整体性。 4)通过1个两层砖砌体结构缩尺模型的拟静力试验,对窗间墙扶壁柱配筋率为1.67%的砌体模型的破坏特点、抗震性能、窗间墙的破坏模式以及纵墙的破坏机制等进行了研究。结果表明,窗间墙扶壁柱配筋率增大到一定程度时,扶壁柱与两侧砖砌体部分的协调变形能力很差,导致模型发生层间破坏机制,窗间墙剪切破坏,纵墙发生“强梁弱柱”式破坏,部分窗间墙出现垮塌破坏,最终形成倒塌机制,模型的延性和耗能能力均较差。 5)进行了2个砖砌体结构缩尺模型(窗间墙扶壁柱配筋率为0.77%)的拟静力试验,分别对普通砖砌体窗间墙模型和窗间墙锚固配筋模型的破坏特征、承载能力、变形能力、延性和耗能能力、窗间墙的破坏模式、纵墙的宏观破坏机制及其控制条件等进行了研究。结果表明,普通窗间墙模型发生层间破坏机制,窗间墙剪切破坏,纵墙发生“强梁弱柱”式破坏,模型最终形成倒塌机制；窗间墙锚固配筋模型发生整体型破坏,窗间墙弯曲破坏,纵墙的宏观破坏具有“强柱弱梁”特征,模型的破坏形态、延性和耗能能力等均得到显著改善,层间变形均匀。因此,窗间墙局部锚固配筋的抗震设计方法能够实现对结构地震破坏机制的有效控制,而保证相邻层两窗间墙的受弯承载力之和高于相邻两窗下墙承载力之和有利于“强柱弱梁”式破坏机制的形成。 6)采用钢筋网水泥砂浆面层对砌体结构教学楼的纵向窗间墙进行三面抗震加固并采取锚固措施,通过模型拟静力试验对加固窗间墙砖砌体结构模型的破坏特点、抗震性能、窗间墙的破坏模式、纵墙的破坏机制及其设计控制条件等进行了分析。结果表明,模型发生整体型破坏,窗间墙弯曲破坏,模型的延性和耗能能力比普通砖砌体窗间墙模型得到明显改善,承载能力和变形能力也得到提高,最终形成“强柱弱梁”抗倒塌机制。
[Abstract]:2008 Wenchuan earthquake caused massive destruction of brick masonry structure building, part of the teaching building suffered serious damage or even collapse, the seismic performance of masonry structure buildings under severe earthquake and anti collapse safety caused widespread concern of scholars. Masonry teaching building has great Wall Bay and depth, the quantity is less, with characteristics of vertical wall the higher rate is not conducive to seismic, the current understanding of the seismic performance is mainly based on the earthquake damage investigation and analysis, the current seismic design code for large bay masonry structure seismic damage model design lacks the special regulations, the seismic performance of masonry structure building, the seismic failure mechanism and seismic performance control and the influence of wall between windows and deep into larger the factors of wall is not enough. This paper selects masonry teaching building as the research object, the seismic performance of masonry structure and large bay earthquake The main research work and conclusions are as follows:
1) analysis of the characteristics of masonry structure teaching building and the typical damage characteristic, compares the differences of structural seismic capacity of masonry structure "strong column and weak beam" and "strong beam weak column" two macro failure mechanism and the structure damage reason was analyzed. Aiming at the weak link of the structure seismic forward seismic design suggestions related.
2) the 5 longitudinal wall hysteretic test, seismic performance and its influencing factors were studied. The results show that the wall between windows, according to the requirement of constructional column wall has better seismic capacity, increasing the columns size can damage form and further improve the wall, ductility and energy dissipation. But the increase in column reinforcement ratio to a certain extent but reduce the ductility and energy dissipation capacity of the wall.
3) the 5 transverse wall hysteretic test, analyzes the arrangement of circle beam and constructional column on the failure mode and seismic performance. The results show that the method of circle beam and constructional column setting determines the seismic performance of the wall, according to the current code for seismic design of constructional column in cross wall ends at the same time ensure shear slip occurs wall and foundation beam, transverse wall seismic performance is relatively good; the middle construction column and the seismic performance of a beam or wall has not been effectively improved, but the addition of beam and column specimens, limit deformation after the deformation and failure of wall blocks by middle beam constraint the wall has a good overall, late.
4) through the pseudo static test of 1 layer structure of two scale model of brick masonry wall, the wall between windows column reinforcement ratio for masonry model 1.67% damage characteristics, seismic performance, window wall failure mode and failure mechanism of longitudinal wall were studied. The results show that the wall between windows buttress columns reinforcement ratio increases to a certain extent, coordination and both sides of the brick masonry wall supporting column deformation ability is poor, leading to model delamination mechanism, window wall shear, longitudinal wall of the "strong beam weak column" type of failure, part of the wall between windows appear collapsed, and ultimately the formation of collapse mechanism, ductility and energy dissipation. The model is also poor.
5) the 2 scale model of brick masonry structure (the wall between windows wall reinforcement ratio of the column is 0.77%) the pseudo static test, respectively on the failure characteristics of ordinary brick masonry wall between Windows model and window wall anchorage reinforcement model of bearing capacity, deformation capacity, ductility and energy dissipation capacity and failure mode between windows the wall, the macro failure mechanism of longitudinal wall and control conditions were studied. The results show that the common wall between Windows model layer failure mechanism, window wall shear, longitudinal wall of the "strong beam weak column" failure model, and ultimately the formation of collapse mechanism; window wall anchorage reinforcement model of integral type destroy the wall between windows bending failure, the macroscopic failure of longitudinal wall has strong column and weak beam characteristics, failure model, ductility and energy dissipation capacity were significantly improved, the interlayer deformation. Therefore, the seismic design method of window wall anchor reinforcement can be realized The effective control of the seismic failure mechanism of the structure is ensured, and the sum of the bending capacity of the two windows between adjacent layers is higher than the sum of the bearing capacity of the adjacent two windows, which is beneficial to the formation of the failure mechanism of strong column and weak beam.
6) the reinforced mortar layers of masonry teaching building longitudinal wall between windows three surface seismic strengthening and take reinforcement measures, the pseudo static test model of damage characteristics, brick masonry structure model window reinforcement seismic performance, failure mode and failure mechanism of wall between windows, vertical wall and design control conditions were analyzed. The results show that the model has the overall destruction, window wall bending failure, ductility and energy dissipation capacity of the model than the ordinary brick masonry wall between Windows model is improved, the carrying capacity and deformation capacity is also improved, and ultimately the formation of "strong column and weak beam" anti collapse mechanism.

【学位授予单位】：西南交通大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TU352.11;TU364

【参考文献】