摘要
针对常用有限元软件中弹性连接单元的刚度矩阵开展研究。类似普通梁单元刚度矩阵的分析方法,将弹性连接单元的空间受力状态分解为伸缩、弯曲和扭转三种独立的模式进行分析,并提出两种方式推导弯曲受力模式下的刚度矩阵。对于弯曲受力状态下的刚度矩阵,明确了MIDAS中弹性连接单元输入参数包括弯曲和剪切刚度系数、弹性连接长度和剪切距离比R在刚度矩阵中的表现形式,给出了其刚度矩阵的理论表达式;阐明了剪切距离比R的力学意义,即用以考虑弹性支承两端因剪力传递的弯矩,其对结构的影响只体现在杆端位移结果中,杆端力始终满足静力平衡条件而不受R的影响,并且在R取0.5时,MIDAS中弹性连接的单元刚度矩阵与普通欧拉梁单元的刚度矩阵最为接近。同时通过分析对比,明确了ANSYS和ABAQUS中弹性连接单元的弯剪效应是独立的,这与MIDAS中弹性连接单元在不考虑剪切距离比R时的特性一致。研究成果既有助于理解弹性连接单元刚度矩阵,又为其工程应用提供了参考。
The study was initiated for the stiffness matrixes of elastic connection elements in Finite Element Method(FEM).The derivation was decomposed into three uncoupled conditions,including tension,torsion,and bending,as the derivation for beam elements.Two methods were proposed to derivate the matrix in the bending condition.Following the analysis of the participation of parameters of the elastic connection element in MIDAS,including the bending and shearing stiffness values,the connection length,and the shear distance ratio R,the theoretical expression of the stiffness matrix of the elastic connection element in MIDAS was obtained.Especially,the mechanical implications of the shear distance ratio R were also elaborated:it was used to transfer the bending moment from one end to another due to the shear force;it had influence on the displacement results but not on the static equilibrium condition;the matrix of elastic connection element in MIDAS was close to the matrix of Euler-beam element if R=0.5.Moreover,a comparative investigation was given on the elastic connection elements in ANSYS,ABAQUS and MIDAS.It was found that the shear and bending effects are independent for the elastic connection elements in ANSYS and ABAQUS,which is the case when R is not considered for the elastic connection element in MIDAS.The derivation process and conclusion are instructive for the understanding of stiffness matrixes of elastic connection elements and helpful for practical application.
作者
张军锋
胡连超
温珺博
耿玉鹏
李杰
ZHANG Junfeng;HU Lianchao;WEN Junbo;GENG Yupeng;LI Jie(School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;Communications Construction Company of CSCEC 7th Division Co.,LTD.,Zhengzhou 450003,China;Henan Puze Expressway Co.,LTD,Puyang 457000,China)
出处
《结构工程师》
2023年第6期28-34,共7页
Structural Engineers
关键词
弹性连接单元
刚度矩阵
平面弯曲受力
剪切距离比
有限元软件
elastic connection elements
stiffness matrixes
plane bending condition
shear distance ratio
FEM software
