带填充墙木框架抗震性能及加固方法研究

发布时间：2018-09-13 06:39

【摘要】：中国传统古建筑以木结构为主,并赓续近几千年,但如今完整保留下来的却是甚少。此外,在我国广西、云南等地的农村,以木构架作为承重结构、砌体作为围护墙房屋仍是居民住房的一种主要形式。目前国内外对木框架结构的研究不断增多,并取得一定的研究成果,但是对于带填充墙的木框架研究还是非常少。鉴于此,本文参照清代《工程做法则例》,制作了带砌体填充墙的燕尾榫木框架,对其抗震性能以及加固方法进行研究。本文首先完成了三榀带填充墙木框架低周反复荷载下的试验研究,第一榀框架直接进行低周反复加载试验,第二、三榀框架以最大程度不改变构件原貌(参考古建筑维修原则)为目的,并结合第一榀框架中填充墙破坏形态,对其填充墙采取了水平灰缝嵌筋、墙边缘湿法粘贴钢板进行加固。其中,第二榀框架中的填充墙需进行预开裂后再加固,而第三榀中的填充墙直接进行加固。基于试验研究与理论分析,得到三榀框架的破坏机制、滞回曲线、骨架曲线、承载力、强度退化、刚度退化、延性和耗能能力等抗震性能指标,并对此种加固方法的效果进行评估。试验研究结果表明,无论加固与否带填充墙木框架的滞回曲线都呈现Z型,破坏主要呈现剪切破坏,并存在明显剪切滑移,耗能能力较差,木框架对填充墙有较强的围护作用,当到达极限荷载后,强度并不会下降的很快,后期延性比较大；第二、三榀框架名义屈服荷载相对第一榀框架平均提高32.1%、30.2%,峰值荷载提高27.8%、20.6%；第二榀框架填充墙虽已预开裂(水平裂缝宽度不超过15mm),但是加固完后能恢复到原来的强度。在试验研究的基础上,利用ABAQUS有限元软件建立带填充墙木框架模型,并基于试验结果对带填充墙木框架模型进行修正。依据有限元模型,对带填充墙木框架在水平力作用下平面内受力、墙体裂缝发展趋势进行了详细的论述。并通过对不同影响因素的分析,包括框架跨高比、砌体平均抗压强度、填充墙厚度,得到了各参数对带填充墙木框架荷载-位移关系曲线的影响规律。此外,基于现有理论及试验结果,建立了带填充墙木框架的恢复力模型；利用有限元变参数拟合结果,提出带填充墙木框架三折线刚度公式,并与试验结果进行比较,为带填充墙木框架抗震弹塑性分析提供参考依据。
[Abstract]:Traditional Chinese architecture is dominated by wood structures and has lasted for thousands of years, but few of them remain intact. In addition, in the rural areas of Guangxi and Yunnan, the timber frame is used as the load-bearing structure, and the masonry as the enclosing wall house is still one of the main forms of residential housing. At present, there are more and more researches on wood frame structure at home and abroad, and some research results have been obtained, but the research on wood frame with infilled wall is still very few. In view of this, according to the code of practice of engineering in Qing Dynasty, this paper makes a dovetail tenon frame with masonry infilled wall, and studies its seismic performance and reinforcement method. In this paper, the experimental study of three wooden frames with infilled walls under low cyclic loading is first completed. The first frame is directly subjected to low cycle repeated loading. With the aim of not changing the original appearance of the members to the maximum extent (referring to the maintenance principle of the ancient buildings) and combining the failure form of the first frame with the infilled wall, the three frames adopted horizontal gray joint reinforcement, and the wall edge was strengthened with steel plate by wet method. Among them, the second one needs to be pre-cracked and then strengthened, while the third one is directly strengthened. Based on experimental research and theoretical analysis, three seismic performance indexes, such as failure mechanism, hysteretic curve, skeleton curve, bearing capacity, strength degradation, stiffness degradation, ductility and energy dissipation capacity, are obtained. The effect of this reinforcement method is evaluated. The experimental results show that the hysteretic curves of wooden frame with or without reinforcement are Z-shaped, and the failure is mainly caused by shear failure, and there is obvious shear slip, poor energy dissipation, and the wooden frame has a strong enclosing effect on the infilled wall, and the results show that the hysteretic curve of the frame is Z-shaped, and the failure is mainly caused by shear failure. When the ultimate load is reached, the strength does not decrease quickly and the ductility of the later stage is relatively large. Second, the nominal yield load of the three frames increases by 32.1and 30.2and the peak load increases by 27.8and 20.6in comparison with the first frame. Although the second frame infilled wall has been pre-cracked (the width of horizontal crack is not more than 15mm), it can be restored to the original strength after reinforcement. On the basis of the experimental research, the model of the frame with filled wall is established by using ABAQUS finite element software, and the model of the frame with filled wall is modified based on the test results. According to the finite element model, the development trend of wall cracks and the in-plane force under horizontal force are discussed in detail. Through the analysis of different influencing factors, including the ratio of span to height of frame, the average compressive strength of masonry, and the thickness of infilled wall, the influence of various parameters on load-displacement relationship curve of wooden frame with infilled wall is obtained. In addition, based on the existing theory and experimental results, the restoring force model of wooden frame with filled wall is established, and the three-fold stiffness formula of the frame with filled wall is put forward by using the finite element variable parameter fitting results, and the results are compared with the experimental results. It provides reference for seismic elastoplastic analysis of wooden frame with filled wall.
【学位授予单位】：东南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU352.11;TU366.2

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