含嵌固墙体古建筑木结构震害数值模拟研究

以四川广元市某古建筑木结构为例,在考虑墙体嵌固作用的基础上,研究了汶川地震下古建筑的震害症状与地震响应状况。采用ANSYS软件对该古建筑榫卯节点的半刚性特征及砖砌体与木构架的嵌固作用进行了模拟,并建立了结构的有限元模型。通过模态分析,获得了结构的基频和主振型;通过将汶川波进行调幅作用于该结构,获得了结构在不同时刻的内力及变形峰值,并获得了典型节点的地震响应曲线。结果表明:考虑墙体的嵌固作用后,该古建筑的基频为1.59Hz,振动形式以第一振型为主,地震作用下木构架产生的位移很小,内力均在容许范围内,且保持稳定的振动状态;墙体由于强度不足,在某些部位将产生破坏,与震害现状基本吻合。     

陶粒粉煤灰配筋砌体墙抗震性能试验及理论研究

提出一种新型配合比的陶粒粉煤灰发泡混凝土作为砌体墙材料,对该种绿色材料进行基本力学性能试验,得到其砌块和砌体的力学指标和本构方程;设计了两榀陶粒粉煤灰配筋砌体墙,通过拟静力试验检验其抗震性能,并与其他绿色材料配筋砌体墙进行对比.建立与试验相关的数值模型,通过数值模型扩展分析,研究改变关键参数对墙体抗剪承载力的影响,并提...     

性能增强古建筑砌体墙抗震性能试验及有限元分析

为提高古建筑砌体结构抗震性能,设计制作了3组古建筑砌体试块和3片古建筑砌体墙试件,分别利用环氧树脂和甲基丙烯酸甲酯进行性能增强。通过试块的材料力学性能试验研究其力学性能,提出了性能增强古建筑砌体的本构关系;通过墙体的拟静力试验研究了性能增强古建筑砌体墙的破坏形态、滞回性能、延性、耗能能力等。结果表明:高分子材料能够有效约束古建筑砌体结构墙体裂缝的开展,提高墙体的承载力和变形能力,其中采用环氧树脂进行性能增强后,墙体承载力和延性相对于未增强墙体分别提高了30%和31%,采用甲基丙烯酸甲酯进行性能增强后,墙体承载力和延性分别提高了18%和42%;性能增强后墙体的滞回环面积和等效黏滞阻尼系数均大于未增强墙体,耗能能力得到增强;最后根据拟合试验曲线建立性能增强古建筑砌体的本构模型,并进行了有限元分析,有限元计算结果与试验结果吻合较好,可为古建筑砌体结构抗震保护提供参考。     

底层框架—抗震墙砖房抗震性能研究

通过对结构进行静力弹塑性分析,研究了底层设置不同数量抗震墙对结构薄弱楼层位置和整体结构抗震能力的影响,提出了应合理设置底层抗震墙的数量,使这类结构的底层与第二层的承载力尽量均匀。     

Parametrical study of masonry walls subjected to in-plane loading through numerical modeling

This paper deals with the numerical assessment of the influence of parameters such as pre-compression level, aspect ratio, vertical and horizontal reinforcement ratios and boundary conditions on the lateral strength of masonry walls under in-plane loading. The numerical study is performed through the software DIANA^® based on the Finite Element Method. The validation of the numerical model is carried out from a database of available experimental results on masonry walls tested under cyclic lateral loading. Numerical results revealed that boundary conditions play a central role on the lateral behavior of masonry walls under in-plane loading and determine the influence of level of pre-compression as well as the reinforcement ratio on the wall strength. The lateral capacity of walls decreases with the increase of aspect ratio and with the decrease of pre-compression. Vertical steel bars appear to have almost no influence in the shear strength of masonry walls and horizontal reinforcement only increases the lateral strength of masonry walls if the shear response of the walls is determinant for failure, which is directly related to the boundary conditions.     

配筋混凝土砌块砌体小高层框支结构抗震研究

论述了与配筋混凝土砌块砌体小高层框支结构相关的剪力墙及房屋抗震设计和性能的研究进展概况，介绍了其需要重点研究的几个方面，促进其在抗震设计中广泛地应用。     

平面不规则砌体结构房屋震害情况评估

结合GB50011-2010建筑抗震设计规范相关规定,针对三幢不规则砌体房屋在地震中的破坏情况进行了分析,并评估其震损程度,指出了房屋规则性在建筑和结构设计中的重要性。     

设置透风孔的超高层建筑风荷载特性

采用同步测压技术,进行设置透风孔的超高层建筑刚性模型风洞试验,对该类建筑物的风荷载特征进行研究。结果表明:孔洞附近,顺风向阻力表现出一定涡激力特性,横风向升力功率谱的谱峰下降幅度较大,阻力与升力系数的根方差均减小,但扭转向扭矩系数根方差的减小幅度有限。受孔洞影响的区域,阻力系数与扭矩系数的自相关性减弱,但升力系数的自相关性增强,阻力系数、升力系数的相干函数衰减程度减弱,相干系数的数值减小。设置透风孔后,超高层建筑升力系数、扭矩系数与阻力系数的互相关性不能再忽略不计,但升力系数与扭矩系数之间的互相关性有所减弱。     

GFRP复合材料加固带壁柱砖墙抗震性能试验研究

对玻璃纤维复合材料(Glass Fiber Reinforced Polymer,GFRP)加固带壁柱砖墙抗震性能进行试验研究。通过1片未加固带壁柱砖墙和8片GFRP加固带壁柱砖墙在低周往复荷载作用下的抗震性能试验,阐述了各试件的破坏特征;研究GFRP加固前后墙体的滞回特性、刚度及退化特性、变形性能、耗能性能等变化规律,以及加固方式、加固量和“对拉”锚固措施对加固效果的影响。研究结果表明:加固方式对墙体的刚度退化性能和变形性能影响不大,但对墙体的耗能性能影响较明显;按照本文提出的加固方式粘贴GFRP能够有效地提高墙体的极限荷载、减缓墙体的刚度退化、增强其变形能力和耗能能力;同时考虑采用混合加固方式、增大加固量、采用锚固措施三因素时,墙体的抗震性能较好。     

开洞矩形截面超高层建筑局部风压风洞试验研究

基于一栋立面上有多个开洞的矩形截面超高层建筑的刚性模型表面压力测量风洞试验结果,分析了矩形截面超高层建筑在长边立面上不同开洞工况下建筑各表面平均风压系数和最不利风压系数的变化规律。试验结果表明:当建筑长边迎风时,开洞使得背风面洞口附近的平均风压系数绝对值增大,但迎风面上的平均风压系数变化很小;当建筑短边迎风时,开洞对洞口附近的平均风压系数和最不利正风压系数均只有微弱影响,但对其最不利负风压系数却有很大影响,特别是中部开洞,将使其周围的最不利负风压系数增大一倍以上;开洞对短边立面上的最不利风压系数不产生明显的影响。为有结构开洞的高层建筑洞口附近的围护结构设计提供了参考数据。     

对多层砌体结构房屋抗震设计的反思

从力学角度出发,探讨了地震作用对砌体结构的影响,介绍了砌体结构房屋的震害情况,阐述了学校在抗震方面存在的缺陷,鉴于此提出了学校房屋设计时应注意的事项,以避免或减少地震灾害带来的损失.     

不同影响因子对砌体建筑震害影响程度的分析及研究

通过提出了一种主观、客观相结合的权重确立方法,研究不同影响因子对砌体建筑震害影响程度。采用模糊层次分析结合灰色关联度分析相结合,以确定影响因子对砌体建筑抗震性能的影响程度的综合权重。通过研究发现：层次分析法结合灰色关联度法确立的综合权重,既反映了专家意见及建议,又反映了实际样本数据的信息,使得综合评价结果更合理和客观。     

底部框架-抗震墙砌体房屋的转换层设计研究

从转换层的墙体设计、楼板设计以及侧移刚度比和强度比的控制四方面探讨了底部框架—抗震墙砌体房屋的转换层设计,提出了具体的处理措施和设计方法,并指出转换层的结构设计是底部框架—抗震墙砌体房屋设计的关键。     

开洞的钢板和型钢支撑-混凝土组合剪力墙抗震性能试验研究

根据实际工程,对长宽比为3.08的筒体的短边墙体进行模型试验。试验模型为钢管边框,内部设置型钢支撑、局部开洞的钢板-混凝土组合剪力墙。采用低周反复模式加载,分析试件极限承载力、构件延性和破坏特征。通过试验分析,钢板-混凝土剪力墙的钢管边框、钢板、钢框架能很好地协同工作,可较明显提高组合剪力墙的承载力和延性。试验结果同时也指出,开洞组合剪力墙在设计中应采取构造加强措施,有利于进一步提高结构的承载力和延性。     

底部框架砌体房屋设计方法新要点

结合2010新抗震规范,针对底部框架砌体房屋设计要点进行了总结归纳,分别阐述了该种结构的设计方案要求、结构布置要求、抗震墙设置、框架柱设置、构造柱设置等方面的注意事项,并提出了结构计算要点,以指导实践。     

Correlation analysis of a reinforced-concrete building under tsunami load pattern and effect of masonry infill walls on tsunami load resistance

The 26 December 2004 Indian Ocean tsunami caused damage to many buildings and killed a lot of people in several Indian Ocean countries, including Thailand. Several reinforced-concrete (RC) buildings in Southern Thailand that were gravity-load-designed buildings suffered damage due to the tsunami. To understand the behaviour of RC buildings under tsunami loads, the one-story building, which was the former office of the Thai Meteorological Department located in Phang-Nga province, was tested under tsunami load patterns. In this research, the RC building is modelled for three-dimensional non-linear static pushover analysis. In the building model, masonry infill walls are idealised as diagonal struts by using uniaxial non-linear springs, and plastic hinges are modelled by non-linear fibre elements. The results of the building model agree well with test results. The effect of masonry infill walls is investigated by considering various wall arrangement patterns. The building with masonry infill walls can resist the lateral load two times higher than the resistance of the building without masonry infill wall. The masonry infill walls with the appropriate arrangement can significantly improve the load-resisting capacity of the building under tsunami loads.     

Numerical analysis of concrete block masonry beams under three point bending

A parametrical study of masonry beams through numerical modelling has been performed in order to better understand the mechanical behaviour of these elements. Boundary conditions, geometry and reinforcement ratios are the main parameters analysed in this study. The numerical simulation is performed with DIANA^® software, based on the Finite Element Method. A comparison between numerical and experimental results is presented in order to validate the simulation. In conclusion, it was verified that the behaviour of masonry beams is greatly affected by the boundary conditions and geometry, as expected. With regard to reinforcement, it was noted that horizontal reinforcement increases the flexural strength of beams. On the other hand, variation in horizontal reinforcement had no influence on the shear resistance of masonry beams. Finally, the combination of horizontal and vertical reinforcements is shown to enhance the flexural and shear behaviour of masonry beams.     

多层砌体结构房屋的整体弯曲验算初探

通过两组算例，对砌体结构房屋承重墙水平截面抗震承载力进行验算，分析地震作用下倾覆弯矩产生的应力对砌体结构房屋承载能力的影响，同时提出了砌体结构房屋整体弯曲验算的方法。