Structural damage assessment by using strain frequency response function

Abstract

The damage detection of bridge structures by using modal assurance criteria (MAC) based damage index is carried out in this study. The basics principle of the modal assurance criteria is illustrated at first. The strain frequency response function is utilized to construct a damage index. The feasibility of the proposed detection approach is investigated through numerical simulation. The results from this study demonstrate that the detection approach proposed can identify the damage events can be determined without establishing mathematical model. The MACsfrf index is more sensitive to structural damage than MAC index. The observations from numerical investigation indicates that strain responses regarding higher mode shapes are more significant than those of the lower mode shapes in the damage detection. The damage indices can still identify the damage from the contaminated modal information for the designated noise intensity.