【作者】 刘洋；

【导师】 王新武； 张伟； 刘光军；

【作者基本信息】 河南科技大学 ， 工程硕士（专业学位）， 2020， 硕士

【摘要】 偏心支撑框架在承受较大的水平荷载时,可通过耗能梁段的屈曲变形消耗地震能量,从而保护其它结构在大震作用下保持弹性阶段或部分塑性阶段,具有较高的承载力和耗能能力。传统偏心支撑钢框架结构中,往往采用焊接连接的方式,耗能梁与框架梁作为一个整体进行设计,这样不利于框架的震后修复。为了解决这一问题,根据“强柱弱梁”的设计理念,采用较低屈服点的Q235钢作为耗能梁,Q345钢作为框架其他构件,将耗能梁设计为齐平式端板螺栓连接,梁柱节点采用半刚性连接的形式,防止了焊接连接造成的节点间脆性断裂的问题,同时,耗能梁采用可替换设计,有利于震后的修复,提高了结构的经济效益。本文通过拟静力试验和非线性有限元分析,对带有可替换耗能梁的半刚接偏心支撑钢框架进行了分析,具体内容如下:(1)对两个1:2缩尺比例单层单跨平面钢框架进行低周循环加载试验。通过试验分析了框架的变形特性、塑性发展情况及破坏模式,分析了框架的强度、刚度、滞回性能、耗能特性。(2)采用ABAQUS有限元分析软件,依据试验框架数据建立有限元实体模型,对模型进行非线性分析,结果表明,模型的应力发展情况、变形情况、荷载-位移曲线均与试验由较好的拟合效果。(3)通过改变耗能梁的长度、框架的轴压比,研究框架抗震性能的差异性。结果表明:破坏主要发生在耗能梁处,且耗能梁先于框架屈服并消耗能量;适当提高耗能梁处端板厚度可以提高框架的水平承载力。梁柱节点处在加载过程中始终没有屈曲破坏,梁柱节点处的螺栓所受荷载较小,采用半刚性连接对框架的抗震性能影响较轻。采用长度比较小的剪切型耗能梁具有较高的承载力和初始刚度,长度过长不利于耗能梁腹板处剪切变形消耗能量。轴压比在0.3以下时,轴压比对框架的抗震性能影响较小,轴压比达到0.6和0.8时,易导致柱脚在加载过程中的屈曲。更多还原

【Abstract】 When the eccentrically braced frame is subjected to a large horizontal load,it can consume seismic energy through the buckling deformation of the link,thereby protecting other structures from maintaining the elastic stage or part of the plastic stage under the action of large earthquakes,with higher bearing capacity and consumption ability.In the traditional eccentrically braced steel frame structure,the welding connection method is often used,and the energy dissipation beam and the frame beam are designed as a whole,which is not conducive to post-earthquake repair of the frame.In order to solve this problem,according to the design concept of "strong column and weak beam",Q235 steel with lower yield point is used as the link,and Q345 steel is used as other components of the frame,and the link is designed as flush end plate bolt connection The beam-column joints adopt the form of semi-rigid connection to prevent the brittle fracture between the nodes caused by the welded connection.At the same time,the link adopts the replaceable design,which is conducive to post-earthquake repair and improves the economic benefits of the structure.This paper analyzes the semi-rigid eccentrically braced steel frame with replaceable link through pseudo-static test and nonlinear finite element analysis.The details are as follows:(1)Carry out low-cycle loading test on two 1:2 scale single-layer single-span plane steel frames.The deformation characteristics,plastic development and failure modes of the frame were analyzed through experiments,and the strength,stiffness,hysteretic performance and energy consumption characteristics of the frame were analyzed.(2)Adopt ABAQUS finite element analysis software,establish a finite element solid model based on the test frame data,and perform nonlinear analysis on the model.The results show that the stress development,deformation and load-displacement curve of the model are in good agreement with the test.Fitting effect.(3)By varying the length of the link and the axial compression ratio of the frame,the difference in seismic performance of the frame is studied.The results show that the failure mainly occurs at the link,and the link yields and consumes energy before the frame;properly increasing the end plate thickness at the link can increase the horizontal bearing capacity of the frame.There is no buckling failure at the beam-column joint during the loading process.The bolts at the beamcolumn joint are less loaded,and the semi-rigid connection has less impact on the seismic performance of the frame.the shear link with a shorter length has higher bearing capacity and initial stiffness,and the longer length is not conducive to the energy consumption of shear deformation at the web of the energy dissipation beam.When the axial compression ratio is below 0.3,the axial compression ratio has little effect on the seismic performance of the frame.When the axial compression ratio reaches 0.6 and0.8,it is easy to cause the buckling of the column foot during loading.更多还原