Dynamic calculation of beam-column model based on three-variable element free Galerkin method
WU Chen;ZHOU Ruizhong;XIANG Hong;School of Civil Engineering,Fujian University of Technology;Fujian Provincial Key Laboratory of Advanced Technology and Informatization in Civil Engineering;College of Civil Engineering,Fuzhou University;
Element Free Galerkin Method( EFM) does not require the design of meshes,which is an extremely tedious and time-consuming process. Furthermore,when a construction is subjected to seismic motion,large deformations of the mesh may encounter re-meshing. Interpolation functions for three-variable is set up in this paper based on Moving Least Squares Method. In which,horizontal displacement,vertical displacement and rotation angle are included. Mass matrix and stiffness matrix in local coordinate are calculated and assembled into global coordinate after coordination transformation,and then structural dynamic characteristics can be calculated and the earthquake response can be gained through solving discrete dynamic equation. The influence of scaling factor to weight function,interpolation function and their derivatives are analyzed. It is indicated that with the increase of the scaling factor,the weight function has not remarkable change,but the absolute values of its derivative decrease obviously,and the change will affect the interpolation function. When the small changes in scaling factor,it has little effect on the axial component of the interpolation function and its derivative,but the transverse component and the rotationangle have great changes. After the trial,it is recommended that the scaling factor of three-variable EFG in dynamic calculation can be set as 3. 0 to 4. 0. Three-variable EFG is applied to displacement calculation of beam-column model under harmonic load and ground motion. With comparison of analytical solution and finite element solution,it's indicated that three-variable EFM can be applied in beam-column model and the parameter is reasonable.