Super element method for characteristic of modal-frequency behavior analysis of tall building considering torsional coupling vibration

This paper presents the super element method for calculating natural characteristic of tall building considering torsional coupling vibration.The laterally loaded structures are thought of as equivalent columns.When performed space cooperating analysis,this method is applied to calculate lateral stiffness matrix.After every lateral stiffness matrix is obtained,the lateral and torsional stiffness matrix of the whole system is assembled.Substituted into the free vibration equation of undamped system,the natural characteristic can be solved by the present numerical method.The degree of freedom can be greatly decreased.In addition,the lateral stiffness matrix has the unified formula for the frame,frame-shear wall structure as well as shear wall structure.The method is simper in calculation and programming.