考虑节点刚度的预制混合梁框架抗侧刚度研究  

Study on Lateral Stiffness of Precast Hybrid Beam Frames Considering Joint Stiffness

作　　者：张锡治 赵冬[3] 李星乾 陈昆 Zhang Xizhi;Zhao Dong;Li Xingqian;Chen Kun(Architectural Design&Research Institute of Tianjin University,Tianjin 300072,China;Key Laboratory of Coast Civil Structure Safety of Ministry of Education(Tianjin University),Tianjin 300072,China;School of Civil Engineering,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学建筑设计规划研究总院有限公司,天津300072 [2]滨海土木工程结构与安全教育部重点实验室(天津大学),天津300072 [3]天津大学建筑工程学院,天津300072

出　　处：《天津大学学报（自然科学与工程技术版）》2021年第3期228-236,共9页Journal of Tianjin University：Science and Technology

基　　金：国家自然科学基金资助项目(51578369);天津市科技计划资助项目(19YDLYSN00120).

摘　　要：基于边界条件为两端刚接的钢-混凝土预制混合梁,推导了考虑连接半刚性影响的预制混合梁刚度矩阵.当螺旋弹簧转动刚度趋于无穷大时,刚度矩阵将退化为两端刚接的预制混合梁单元刚度矩阵.通过引入无量纲参数p、δ对刚度矩阵进行简化处理.其中预制混合梁刚度系数p介于0~1之间,其反映了预制混合梁的半刚性特性.当节点为铰接时,刚度系数p趋近于0;当节点为刚接时,刚度系数p趋近于1.对单层单跨框架结构抗侧刚度进行分析,研究了预制混合梁钢梁长度与总长度比α、钢梁与混凝土抗弯刚度比e、结构柱线刚度i和螺旋弹簧转动刚度k对抗侧刚度的影响.结果表明:框架节点转动刚度、预制混合梁长度比及抗弯刚度比、框架柱线刚度均对框架抗侧刚度具有较大影响.随着节点转动刚度增大,结构抗侧刚度显著增大.随着α减小或e、i增大,节点转动刚度的变化对抗侧刚度的影响增大,抗侧刚度将对节点刚度更敏感.同时,计算了一个三层预制混合梁框架结构在水平荷载作用下的侧移量,并与有限元模拟计算结果进行对比分析.结果表明:采用推导刚度矩阵计算的理论值与模拟值吻合较好,随着节点转动刚度的增大,框架侧移量与层间位移角逐渐减小,且各层侧移量与层间位移角之间的差距也不不断减少.The stiffness matrix of precast hybrid steel-concrete beam with semi-rigid connections was deduced on the basis of the boundary conditions of the fixed precast hybrid beam.The stiffness matrix can degenerate into the stiffness matrix of fixed precast hybrid beam when the rotational stiffness of helical springs approaches infinity.The stiffness matrix was simplified by introducing dimensionless parameters p andδ.The stiffness coefficient of precast hybrid beam p which ranges between 0~1 reflects the characteristics of semi-rigid joints of precast hybrid beam frames.When the joints are hinged,the stiffness coefficient p tends to 0,and the stiffness coefficient p tends to 1 when joints are rigid.A one-story one-span frame was used to analyze and the effects of length ratioα,rigidity ratio e,linear rigidity of frame column i and rotational stiffness k on lateral stiffness was studied.The results show that the rotational stiffness of frame joints,length ratio and rigidity ratio of precast hybrid beams and linear rigidity of frame columns have a great influence on the lateral stiffness of frames.The lateral stiffness increases with the increase of k obviously.The change of rotational stiffness can cause more influence on lateral stiffness of frames which is more sensitive to connection rigidity with decreases ofαor increase of e and i.Moreover,the lateral displacements of three-story frames under horizontal loads were calculated and finite element method was used to compare with calculated results.The results show that the lateral displacements of frames fit well with the finite element analysis results,proving that the deduced stiffness matrix is accurate.The lateral displacements,the story drift angles of frames and the gap between different story lateral displacements and story drift angles will decrease with the increase of rotational stiffness of joints.

关 键 词：钢-混凝土预制混合梁 半刚性连接 刚度矩阵 抗侧刚度 有限元分析 

分 类 号：TU398.2[建筑科学—结构工程]