基于动力直接刚度法分析轴向变刚度钢-混组合梁自振特性  

Natural vibration characteristics of steel-concrete composite beams with axial variable stiffness based on dynamic direct stiffness method

作　　者：孙琪凯 张楠[1,3] 刘潇 陶晓燕 王章明 龚怡明 SUN Qikai;ZHANG Nan;LIU Xiao;TAO Xiaoyan;WANG Zhangming;GONG Yiming(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China;State Key Laboratory for Track Technology of High-Speed Railway,Beijing 100081,China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081 [3]高速铁路轨道技术国家重点实验室,北京100081

出　　处：《振动与冲击》2021年第15期296-302,共7页Journal of Vibration and Shock

基　　金：高速铁路轨道技术国家重点实验室开放课题基金(2018Y179)。

摘　　要：推导了基于动力直接刚度法的钢-混组合梁自振特性有限元计算模型。模型中考虑了混凝土板和钢梁之间的剪切滑移效应,得到了6个自由度的单元动力刚度矩阵。给出了边界条件为一般弹性支撑时,钢-混组合梁自振特性的求解过程。由于该模型推导过程中没有引入近似位移场或力场,而且可以分析一般弹性支撑的沿轴向变刚度的钢-混组合梁,因此计算结果是准确的。最后,通过两孔简支钢-混组合梁的室内试验,对比理论分析、ANSYS FEA和试验测试结果,验证该有限元计算模型的正确性。然后以已发表的文章中的具有简支-简支、固支-自由、固支-简支和固支-固支等四种常见边界条件的简支的数值模型计算结果为参考,进一步验证计算模型的适用范围。结果表明:推导得到的动力直接刚度矩阵可应用于求解一般弹性边界条件下,沿轴向变刚度的钢-混组合梁的自振特性。The finite element(FE)calculation model for natural vibration characteristics of a steel-concrete composite beam based on dynamic direct stiffness method was derived considering shear-slip effect between concrete slab and steel beam,and the element dynamic stiffness matrix with 6-DOF was obtained.The solving process for natural vibration characteristics of a steel-concrete composite beam with general elastic supports was deduced.As no approximate displacement field or force field was introduced in derivation process of the model and it could be used to analyze steel-concrete composite beams with general elastic supports and variable stiffness in axial direction,the calculation results were accurate.Finally,through laboratory tests of a two-hole simply supported steel-concrete composite beam,the correctness of the FE calculation model was verified by comparing the calculation results of theoretical analysis,ANSYS and the derived FE model with test results.Meanwhile,the application scope of the FE calculation model was further verified by referring to the calculation results of the simply supported beam numerical model published in literature under 4 common boundary conditions of simply supported-simply supported,fixed-free,fixed-simply supported and fixed-fixed.The results showed that the derived dynamic direct stiffness matrix can be used to solve natural vibration characteristics of steel-concrete composite beams with axial variable stiffness under general elastic boundary conditions.

关 键 词：钢-混组合梁 动力直接刚度法 一般弹性支承 固有频率 试验研究 

分 类 号：U441.3[建筑科学—桥梁与隧道工程] U24[交通运输工程—道路与铁道工程]