一字形全钢防屈曲耗能支撑试验及抗震性能研究
发布时间：2019-02-19 21:43
【摘要】：上世纪以来，世界范围内的大地震已造成了惨痛的人员伤亡与巨大的经济损失。各国也愈发重视抗震工程的研究，因此消能减震技术得以迅速地发展。防屈曲支撑的发明初衷是为了防止普通支撑在地震往复荷载下的受压屈曲，而研究表明，防屈曲支撑不仅能够提高结构的侧向刚度，还可以耗散地震能量。目前的研究多集中于外围约束单元为钢筋混凝土、钢管混凝土或方钢管、圆钢管的防屈曲支撑，且对于以不同钢材作为内核芯材的防屈曲支撑对结构整体抗震性能的影响尚未有具体的研究成果。本文针对一种一字形内核外包双腹板工字形钢的新型防屈曲支撑进行了试验及数值研究，主要内容如下： 首先对采用LY225和SN490这两种不同芯材的8根防屈曲支撑构件进行循环往复加载试验，研究该一字形防屈曲支撑在循环往复荷载作用下的滞回曲线、受力性能、破坏模式，并通过对比试验，考察该支撑在不同内核芯材和不同支撑长度下的性能差异。结果表明以LY225为内核芯材的支撑的低周疲劳性能、塑性变形能力、附加阻尼比、延性等都优于以SN490为内核芯材的支撑，支撑长度增加，其低周疲劳性能和塑性变形能力会有所降低，支撑的受压段强化幅度则增大。 其次，通过有限元软件ABAQUS对试验的试件进行简化数值模拟。由于钢材的强化，目前广泛运用的双折线及三折线模型无法准确模拟往复荷载下支撑的响应，，构件的耗能能力与承载力水平明显被低估。本文利用随动强化和等向强化的组合模型提出试件的杆单元参数设定，旨在准确模拟不同芯材下支撑的滞回曲线形状，以进行带防屈曲支撑框架结构的弹塑性分析。 最后，设计了两栋混凝土框架结构，分别添加了以SN490、LY225和LY100为内核芯材的防屈曲支撑，并设定支撑刚度一致和屈服力一致两种工况，进行了各烈度下结构的弹塑性时程分析。结果表明：在支撑刚度已定的情况下：对于多层框架结构，选用SN490作内核芯材的支撑减震效果要优于LY225和LY100；对于高层结构，选用LY100为内核芯材则能得到更小的层间位移。在支撑屈服荷载已定的情况下，选用LY100为内核芯材的减震效果最好；人字形防屈曲支撑的交叉处梁容易出现塑性铰。
[Abstract]:Since last century, large earthquakes around the world have caused heavy casualties and huge economic losses. Various countries pay more and more attention to the research of seismic engineering, so the technology of energy dissipation and shock absorption has been developed rapidly. The original purpose of anti-buckling bracing is to prevent the buckling of ordinary braces under seismic reciprocating load. The research shows that buckle-resistant braces can not only improve the lateral stiffness of structures but also dissipate seismic energy. At present, most of the research focuses on the buckling-resistant brace of reinforced concrete, concrete-filled steel tube or square steel tube, and circular steel tube. Moreover, there has not been any concrete research results on the effect of anti-buckling braces with different steel core materials on the overall seismic performance of the structure. In this paper, an experimental and numerical study on a new type of anti-buckling bracing with double web I-shaped steel with one-zigzag core is carried out. The main contents are as follows: firstly, the cyclic loading tests of eight buckling bracing members with LY225 and SN490 cores are carried out, and the hysteretic curves of the zigzag buckling braces under cyclic reciprocating loads are studied. The performance of the support under different core material and different length of bracing is investigated by comparing the performance of the bracing with the failure mode and the performance difference of the brace under different core material and different supporting length. The results show that the low cycle fatigue performance, plastic deformation ability, additional damping ratio and ductility of LY225 as core material are better than those of SN490 core material, and the support length is increased. The low cycle fatigue performance and plastic deformation ability of the support will be decreased, and the strengthening range of the compression section of the brace will be increased. Secondly, simplified numerical simulation of the test specimen is carried out by finite element software ABAQUS. Due to the strengthening of steel, the widely used double-line and three-fold line models can not accurately simulate the response of braces under reciprocating load, and the energy dissipation capacity and bearing capacity of members are obviously underestimated. In this paper, the parameters of the bar element of the specimen are set up by using the combined model of the following strengthening and isotropic strengthening. The purpose of this paper is to accurately simulate the hysteretic curve shape of the bracing under different core materials, and to carry out the elastic-plastic analysis of the frame structure with buckle-resistant braces. Finally, two concrete frame structures are designed, and the anti-buckling braces with SN490,LY225 and LY100 as core materials are added respectively, and the elastic-plastic time-history analysis of the structures under different intensity is carried out by setting two conditions of uniform support stiffness and yield force. The results show that, for multi-story frame structure, the effect of SN490 as core material is better than that of LY225 and LY100; for high-rise structure, and LY100 as core material can get smaller layer displacement for multi-story frame structure. Under the condition that the yield load of the braces has been fixed, the damping effect of LY100 as the core material is the best, and the plastic hinge is easy to appear in the crossbeam with the herringbone buckling braces.
【学位授予单位】：清华大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU392.1;TU352.11
本文编号：2426906
[Abstract]:Since last century, large earthquakes around the world have caused heavy casualties and huge economic losses. Various countries pay more and more attention to the research of seismic engineering, so the technology of energy dissipation and shock absorption has been developed rapidly. The original purpose of anti-buckling bracing is to prevent the buckling of ordinary braces under seismic reciprocating load. The research shows that buckle-resistant braces can not only improve the lateral stiffness of structures but also dissipate seismic energy. At present, most of the research focuses on the buckling-resistant brace of reinforced concrete, concrete-filled steel tube or square steel tube, and circular steel tube. Moreover, there has not been any concrete research results on the effect of anti-buckling braces with different steel core materials on the overall seismic performance of the structure. In this paper, an experimental and numerical study on a new type of anti-buckling bracing with double web I-shaped steel with one-zigzag core is carried out. The main contents are as follows: firstly, the cyclic loading tests of eight buckling bracing members with LY225 and SN490 cores are carried out, and the hysteretic curves of the zigzag buckling braces under cyclic reciprocating loads are studied. The performance of the support under different core material and different length of bracing is investigated by comparing the performance of the bracing with the failure mode and the performance difference of the brace under different core material and different supporting length. The results show that the low cycle fatigue performance, plastic deformation ability, additional damping ratio and ductility of LY225 as core material are better than those of SN490 core material, and the support length is increased. The low cycle fatigue performance and plastic deformation ability of the support will be decreased, and the strengthening range of the compression section of the brace will be increased. Secondly, simplified numerical simulation of the test specimen is carried out by finite element software ABAQUS. Due to the strengthening of steel, the widely used double-line and three-fold line models can not accurately simulate the response of braces under reciprocating load, and the energy dissipation capacity and bearing capacity of members are obviously underestimated. In this paper, the parameters of the bar element of the specimen are set up by using the combined model of the following strengthening and isotropic strengthening. The purpose of this paper is to accurately simulate the hysteretic curve shape of the bracing under different core materials, and to carry out the elastic-plastic analysis of the frame structure with buckle-resistant braces. Finally, two concrete frame structures are designed, and the anti-buckling braces with SN490,LY225 and LY100 as core materials are added respectively, and the elastic-plastic time-history analysis of the structures under different intensity is carried out by setting two conditions of uniform support stiffness and yield force. The results show that, for multi-story frame structure, the effect of SN490 as core material is better than that of LY225 and LY100; for high-rise structure, and LY100 as core material can get smaller layer displacement for multi-story frame structure. Under the condition that the yield load of the braces has been fixed, the damping effect of LY100 as the core material is the best, and the plastic hinge is easy to appear in the crossbeam with the herringbone buckling braces.
【学位授予单位】：清华大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU392.1;TU352.11
【参考文献】
相关期刊论文 前7条
1 周云,徐彤,俞公骅,李希平;耗能减震技术研究及应用的新进展[J];地震工程与工程振动;1999年02期
2 李国强;胡宝琳;;屈曲约束支撑滞回曲线模型和刚度方程的建立[J];地震工程与工程振动;2007年02期
3 张涛;马小东;;防屈曲耗能支撑的性能简述及研究分析[J];装备制造技术;2009年04期
4 杨秋鸣;;防屈曲支撑框架体系按延性方法设计与按现行规范设计对比[J];工程抗震与加固改造;2013年01期
5 郭彦林,刘建彬,蔡益燕,邓科;结构的耗能减震与防屈曲支撑[J];建筑结构;2005年08期
6 汪家铭,中岛正爱,陆烨;屈曲约束支撑体系的应用与研究进展(Ⅰ)[J];建筑钢结构进展;2005年01期
7 陈敏;唐小弟;;粘弹性阻尼器附加等效阻尼比的计算[J];中南林业科技大学学报;2010年05期
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