Experimental study of structural damage identification based on modal parameters and decay ratio of acceleration signals

摘要

A novel damage assessment method based on the decay ratio of acceleration signals(DRAS)was proposed.Two experimental tests were used to show the efficiency.Three beams were gradually damaged,and then the changes of dynamic parameters were monitored from initial to failure state.In addition,a new method was compared with the linear modal-based damage assessment using wavelet transform(WT).The results clearly show that DRAS increases in linear elasticity state and microcrack propagation state,while DRAS decreases in macrocrack propagation state.Preliminary analysis was developed considering the beat phenomenon in the nonlinear state to explain the turn point of DRAS.With better sensibility of damage than modal parameters,probably DRAS is a promising damage indicator in damage assessment.