节点文献
在役半刚性连接钢框架结构的抗震性能评估
Seismic Performance Evaluation of Existing Steel Frame Buildings with Semi-rigid Connections
【作者】 王宝峰；
【导师】 陈健云；
【作者基本信息】 大连理工大学 ， 防灾减灾工程及防护工程， 2010， 硕士
【摘要】 在役结构指正在使用中的结构,在役钢结构由于已经使用了一段的时间,在自然环境和使用环境的影响作用下,结构必然产生某种程度的损伤和材料的腐蚀老化等不利的现象,这些不利的现象将对在役钢结构的抗震性能产生较大的影响。在钢框架结构的分析与设计中,梁柱的连接通常被认作理想的刚性连接或完全的铰接连接,但采用这种理想的连接模型会造成理论与实际的较大差异,因为任何连接形式的刚度都是介于理想刚接和完全铰接之间的,相对于刚性连接来说,半刚性连接节点具有较强的转动性能和耗能能力,可以抵抗一定的地震荷载,具有很好的抗震性能。因此,研究在役半刚性钢结构的抗震性能及其评估方法对于减轻地震灾害更具实际意义。本文首先对处于不同年份的在役钢框架的节点性能进行了分析,用有限元分析软件ANSYS根据锈蚀的特性分别对锈蚀半刚性节点和刚性节点,采用Solid92实体单元建立不同年份的锈蚀节点模型,分别对刚性节点和半刚性节点进行单调加载以及循环加载分析,分析不同年代的节点性能以及不同的锈蚀程度对性能的影响。为了比较半刚性节点与刚性节点对钢框架性能的不同影响,分别建立了3层、6层、10层一榀两跨的半刚性连接钢框架和刚性连接钢框架,选用实际的地震记录,分别输入进行弹塑性时程分析,得出顶点位移时程曲线、基底剪力时程曲线以及层间位移的包络图,从不同的角度比较半刚性连接钢框架和刚接钢框架的不同反应,以及结构的高度对结构反应的影响。随着在役结构服役时间的增长,结构必然产生一定程度的损伤和材料老化,且在预期剩余使用年限内的地震动作用的超越概率也随之发生变化,在上述分析结果的基础上,对5层2跨的在役半刚性连接钢框架和刚性连接钢框架进行Pushover分析。在不同后续使用年限内的多遇地震和罕遇地震作用下,随着钢框架节点的初始转动刚度的降低,对比了刚性框架与具有不同节点初始转动刚度的半刚性框架的性能点以及易损性曲线,分析了半刚性连接对结构抗震性能的影响,以及同时考虑抗力和地震作用随着后续使用年限的变化,对结构抗震性能的影响。
【Abstract】 Existing structure is the being used structure. As the existing structures had been used for quite some time, under the natural environment and the using environment, existing structures that will inevitably produce some degree of damage and corrosion of materials and other unfavorable phenomena, these unfavorable phenomena will be had a greater impact on the seismic performance of the existing structures. In the traditional analysis and design of the steel frame, in order to simplify the analysis and design process, beam-column connection is recognized as the ideal articulated connection or completely rigid connections, but, this ideal link model will result in huge difference between theory and practice. Because all connections are rigid and fully articulated in between, Relative to the rigid connection, the semi-rigid connected steel frame has the larger rotation capability and energy dissipation capacity which can resist dynamic loads. Therefore, the study of the existing semi-rigid steel structures and their seismic performance evaluation method is more practical significance for the earthquake disaster mitigation.In this paper, firstly, the node performance of existing steel frame structure in different years is been analysed, and use the Solid92 in finite element analysis software ANSYS to establish the rigid connections’and the semi-rigid connections’solid element node models of corrosion in different years, respectively according to the characteristics of corrosion, then, the rigid and semi-rigid joints are conducted on monotonic loading and cyclic loading for nonlinear finite element analysis, then analyse the nodes’performance in different years and the impact of different corrosion on the node properties.To compare the semi-rigid connection with rigid connection on the performance of the steel frame, the elasto-plastic time-history analysis is performed on the 3-layer,6-layer, 10-layer semi-rigid steel frames and rigid steel frames with 3 actual earthquake acceleration records, the vertex displacement-time curves, base shear force-time curves and the story drift envelope diagram are established, in order to compare the reaction of semi-rigid steel frame with rigid steel frame from different angles, and the height of the structure impact on the reaction of the structure.Based on the semi-rigid connections, as the existing semi-rigid structures are been used for some time, the structures inevitably produce some degree of damage and corrosion of materials and other unfavorable phenomena, and with the structure of the growth of useful life, expected remaining useful life of the ground motion exceeding probability is been changed. It is necessary to take into account the characteristics of semi-rigid connections and the impact of corrosion. Some 5-layer exiting steel frames with different semi-rigid connections are established, that the pushover analysis is performed on. Under the frequent earthquake and the rare earthquake in different re-service term, with the reducing of the nodes’initial rotational stiffness, compare the performance points and the vulnerability curve of the rigid frame and different semi-rigid frame, and analyse the semi-rigid connections impact on the seismic performance of the structure. The seismic performance of the steel frame is discussed, under the resistance and seismic action with the change of the re-service term.