DAMAGE DETECTION FOR TRUSS STRUCTURES BASED ON IMPROVED RESIDUAL FORCE VECTOR METHOD

A damage detection method for truss structures based on an improved residual force vector method is proposed.The stiffness connectivity matrix of the truss structures is obtained by the sensitivity analysis, and the stiffness matrix perturbation of the damaged structure can be expanded to a diagonal matrix by the stiffness connectivity matrix,then with its substitution into the residual force vector equation,a new residual force vector equation expressed by the stiffness connectivity matrix is obtained,which can be solved directly,so the stiffness perturbation of truss bars is obtained,therefore,the damaged bars and the damage extents can be detected.Because the complete modal shapes are difficult to get by measurement,the complete modal shapes are obtained by modal expansion.At last,a numerical example of a truss structure is given,the effectiveness of the proposed method is verified.