基于应变能耗储的钢筋混凝土框架结构地震损伤演化研究     

苏佶智  刘伯权  宋猛  马煜东  黄娇 《震灾防御技术》2021,16(3):533-543

结构地震损伤破坏,本质上是地震动输入能量超出结构或构件耗能能力所致。“能量”参数能够综合反映地震动强度、频谱特性以及强震持时对结构破坏的影响,本文基于能量耗散原理建立结构损伤模型,采用有限元软件ABAQUS对3榀单层单跨钢筋混凝土平面框架结构抗震性能进行数值模拟,通过损伤指数量化研究了地震作用下钢筋混凝土框架结构的损伤演化规律。研究表明:基于应变能耗储的结构损伤模型,能够合理有效地反映“位移首超破坏”与“累积损伤破坏”模式,且上、下界收敛;模拟分析得到的滞回曲线和骨架曲线与试验数据吻合较好,数值建模方法适用于以梁、柱构件为主的框架结构抗震性能分析;耗能构件框架梁能够对结构损伤破坏发展和抗震性能劣化起到一定延缓作用,承力构件框架柱的损伤加剧会加速结构抗震性能的劣化;加载幅值较小时,结构依靠混凝土裂缝闭合摩擦消耗能量,“位移首超破坏”所致损伤所占比例较大,随着位移幅值及循环次数的增加,“累积损伤破坏”所致损伤所占比例逐渐增大。  相似文献   

双向水平地震动作用对某钢筋混凝土连续梁桥易损性的影响     

刘黎明  徐超  卜春尧  耿飞  温增平 《震灾防御技术》2021,16(4):671-679

以双向水平地震动作为输入,对钢筋混凝土连续箱梁高架桥开展非线性动力时程分析。建立基于双向水平地震动强度参数的桥梁结构易损性曲面,比较单向及双向水平地震动输入下桥梁结构易损性差异,分析双向水平地震动输入下横桥向地震动强度对桥梁整体易损性的影响规律。研究结果表明,双向水平地震动输入下的桥梁结构易损性明显高于单向地震动输入的情况,且随着横桥向输入地震动强度的增加,结构各破坏状态的超越概率明显增大。  相似文献   

Damages on reinforced concrete buildings due to consecutive earthquakes in Van     

《Soil Dynamics and Earthquake Engineering》2013

Consecutive earthquakes occurred on October 23rd, 2011 in Ercis and on November 9th, 2011 in Edremit that are townships located 90 km and 18 km far from Van city in Turkey, respectively. A total of 28,000 buildings were damaged or collapsed in the city center and the surrounding villages after the Ercis earthquake. This number reached 35,000 after the Edremit earthquake. In the area where the earthquakes occurred, almost all the reinforced concrete buildings were affected.This study presents field observations of damages on reinforced concrete buildings due to the consecutive earthquakes that occurred in Van, Turkey. Damages appearing in the buildings may occur due to several reasons such as site effect, poor construction quality, poor concrete strength, poor detailing in beam-column joints, detailing of stronger beam than column, soft stories, weak stories, inadequate reinforcement, short lap splices, incorrect end hook angle, and short columns. Aftershocks also caused progressive damages on the buildings within 17 days after the earthquakes. According to the results of this study, most of the damaged buildings were not designed and constructed according to the Turkish earthquake code, the so-called Specification for Buildings to be built in Seismic Zones.  相似文献   

钢筋混凝土构件修复加固与抗震性能比较          下载免费PDF全文

柴少峰  王平  王峻  王谦 《地震工程学报》2013,35(4):872-876

钢筋混凝土框架结构在地震作用下应满足强柱弱梁等抗震设计理念,但由于设计和施工各种综合原因所致,在历次地震中,规范要求的"强柱弱梁"理想破环机制始终没有出现,竖向承重构件遭受了不同程度的损伤和破坏,不满足现有规范的相关规定,为了保证钢筋混凝土竖向承重构件不先于水平构件破坏,对于一些重要位置的钢筋混凝土构件进行修复加固显得十分重要。本文以加大截面加固法、外贴碳纤维加固法、喷射混凝土技术加固法、外包钢加固法、外包粘钢加固法等加固处理方式为例,对钢筋混凝土构件的修复加固方法及其抗震性能进行对比分析。研究对于钢筋混凝土构件的修复加固工程具有一定的参考价值。  相似文献   

钢管混凝土边框内藏带斜肋钢板中高剪力墙抗震性能试验     

董宏英  张文江  曹万林  于传鹏 《地震工程与工程振动》2013,33(3)

提出了钢管混凝土边框内藏斜撑肋钢板组合中高剪力墙.为研究这种组合剪力墙的抗震性能,进行了5个不同构造的中高剪力墙模型低周反复荷载试验.分析了试件的损伤特征、承载力、耗能、滞回特性,提出了正截面抗弯承载力计算模型,计算结果与试验符合较好.研究表明:钢管混凝土边框内藏钢板组合剪力墙具有较高的承载力和良好的耗能性能;钢管混凝土边框内藏带斜撑肋钢板中高剪力墙,适于在墙体厚度小于钢管尺寸或内藏钢板厚度较薄的“强边框、弱墙体”情况下应用,可明显减轻钢管混凝土边框底部的损伤,延缓墙体性能退化,提高组合剪力墙的抗震能力.  相似文献   

方钢管混凝土框架抗震性能试验研究与非线性有限元分析     

王先铁  马尤苏夫  王连坤  郝际平  罗古秋 《地震工程与工程振动》2013,33(4)

为研究采用穿芯高强螺栓-端板节点的方钢管混凝土柱-钢梁平面框架的抗震性能,制作了3榀方钢管混凝土框架试件,通过低周反复荷载试验,研究了框架的抗震性能,分析了轴压比、梁柱线刚度比对框架抗震性能的影响.在考虑几何、材料及接触非线性的基础上,采用有限元软件ABAQUS 6.10对试验框架进行了低周反复荷载作用下的精细化数值模拟.与试验结果的比较表明,数值分析结果与试验结果吻合较好,具有较好的精度,可用于方钢管混凝土框架的分析.基于数值分析结果,剖析了框架梁柱连接节点、柱脚等关键受力部位的应力发展过程,明确了框架的受力机理和破坏机制.  相似文献   

Extension of direct displacement‐based design methodology for bridges to account for higher mode effects     

Andreas J. Kappos  Konstantinos I. Gkatzogias  Ioannis G. Gidaris 《地震工程与结构动力学》2013,42(4):581-602

An improvement is suggested to the direct displacement‐based design (DDBD) procedure for bridges to account for higher mode effects, the key idea being not only the proper prediction of a target‐displacement profile through the effective mode shape method (wherein all significant modes are considered), but also the proper definition of the corresponding peak structural response. The proposed methodology is then applied to an actual concrete bridge wherein the different pier heights and the unrestrained transverse displacement at the abutments result in an increased contribution of the second mode. A comparison between the extended and the ‘standard’ DDBD is conducted, while further issues such as the proper consideration of the degree of fixity at the pier's top and the effect of the deck's torsional stiffness are also investigated. The proposed methodology and resulting designs are evaluated using nonlinear response‐history analysis for a number of spectrum‐compatible motions. Unlike the ‘standard’ DDBD, the extended procedure adequately reproduced the target‐displacement profile providing at the same time a good estimate of results regarding additional design quantities such as yield displacements, displacement ductilities, etc., closely matching the results of the more rigorous nonlinear response‐history analysis. However, the need for additional iterations clearly indicates that practical application of the proposed procedure is feasible only if it is fully ‘automated’, that is, implemented in a software package. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

Experimental investigation on dynamic and quasi‐static behavior of low‐rise reinforced concrete walls     

Julian Carrillo  Sergio M. Alcocer 《地震工程与结构动力学》2013,42(5):635-652

Experimental evidence supporting the fact that results from quasi‐static (QS) test of low‐rise reinforced concrete walls may be safely assumed as a lower limit of strength and displacement, and energy dissipation capacities are still scarce. The aim of this paper is to compare the seismic performance of 12 reinforced concrete walls for low‐rise housing: six prototype walls tested under QS‐cyclic loading and six models tested under shaking table excitations. Variables studied were wall geometry, type of concrete, web steel ratio, type of web reinforcement and testing method. Comparison of results from dynamic and QS‐cyclic tests indicated that stiffness and strength properties were dependent on the loading rate, the strength mechanisms associated with the failure mode, the low‐cycle fatigue, and the cumulative parameters, such as displacement demand and energy dissipated. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

Cyclic testing of a single bay reinforced concrete frames with various types of masonry infill     

Jurko Zovkic  Vladimir Sigmund  Ivica Guljas 《地震工程与结构动力学》2013,42(8):1131-1149

In this paper, a contribution of various types of masonry infill to the behaviour of reinforced concrete frames under lateral loads is presented. As a part of the bigger project, ten one‐bay, one‐storey reinforced concrete frames were designed according to the EC8, built in a scale 1:2.5, infilled with masonry and tested under constant vertical and cyclic lateral load. The masonry wall had various strength properties, namely, high strength hollow clay brick blocks, medium strength hollow clay brick blocks and low strength lightweight autoclaved aerated concrete blocks. There were no additional shear connectors between the masonry and frame. The results showed that the composite ‘framed wall’ structure had much higher stiffness, damping and initial strength than the bare frame structure. Masonry infill filled in the load capacity gap from very low (0.05%) to drifts when the frame took over (0.75%). The structures behaved as linear monolithic elements to drifts of 0.1%, reached the maximum lateral capacities at drift of 0.3%, maintained it to drifts of 0.75% and after that their behaviour depended on the frame. Masonry infill had severe damage at drift levels of about 0.75% but contributed to the overall system resistance to drifts of about 1%. At that drift level, the frame had only minor damage and was tested to drifts of about 2% without any loss of capacity. Improvement of the ‘infill provisions’ in the codes could be sought by taking into account the contribution of a common masonry that reduces expected damages by lowering the drift levels. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

Evaluation of fundamental period of low‐rise and mid‐rise reinforced concrete buildings     

George D. Hatzigeorgiou  George Kanapitsas 《地震工程与结构动力学》2013,42(11):1599-1616

Fundamental period of vibration appears to be one of the most critical parameter for the seismic design of buildings because this period strongly affects the magnitude of seismic forces. In this paper, an empirical formula for estimating the fundamental period of reinforced concrete structures is recommended, on the basis of the vibration analysis of 20 different real building configurations. These structures have already been constructed in Greece, and they are analyzed by using in detail 3‐D finite element models and modal eigenvalue analysis. These models take into account the presence of external and internal infill walls, which are usually ignored as nonstructural elements. This neglect leads to unreliable evaluation of period because the infill walls' contribution to the lateral stiffness and therefore to the fundamental period of vibration is also ignored. Furthermore, taking into account that the flexibility of soil elongates the fundamental period, the soil–structure interaction effect is also considered. To achieve a unique, simple, and effective empirical expression for the fundamental period of vibration, a comprehensive nonlinear regression analysis is applied for the datasets of buildings under consideration. This empirical expression is also compared with the similar expressions from the pertinent literature. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献