Supporting Condition Evaluation Method of Cable-Stayed Bridges Based on Modal Assurance Criterion

Abstract

In order to identify the supporting condition of cable-stayed bridges with semi-floating system by using the measured mode shapes, this paper proposed an actual supporting condition evaluation method of cable-stayed bridges based on the indicator of modal assurance criterion (MAC). Firstly, the measured mode shapes and theoretical mode shapes under different supporting conditions could be obtained. Then the corresponding MAC indicator values were calculated, which would be compared to evaluate the supporting condition of bridges. The experiment results revealed that the MAC values between the measured mode shapes and theoretical mode shapes were in good agreement with MAC values above 0.9, which indicated that the actual structural support condition was consistent with the theoretical calculation condition. The experimental results of actual bridges proved that the proposed method in this paper is feasible and effectiveness.