A Fuzzy Krill Herd Approach for Structural Health Monitoring of Bridges using Operational Modal Analysis

摘要

Monitoring bridges is an important issue in the structural safety assessment. As a consequence of inaccessible sections of these structures, the utilization of nondestructive damage identification techniques seems to be vital for maintaining safety and integrity. In this study, a new hybrid Fuzzy Krill Herd approach is performed based on online responses to assess the global structural integrity of an in-service bridge. While the algorithms have been studied previously in the literature, their efficiency in structural health monitoring of a real bridge structure has yet to be investigated. The methodology is applied to two types of steel girders and concrete bridges in this manuscript. The finite element (FE) modeling is considered for further numerical investigation of dynamic characteristics and structural behavior of the bridges. To evaluate the efficiency of the proposed technique, a three-dimensional FE model and a developed simple two-dimensional girders models are simulated. The results indicate the capability of the fuzzy logic approach in obtaining accurate information in the presence of noisy input data or the data with missing values. Based on the results, increasing the number of the measurement modes and using the torsional modes lead to an accurate damage diagnosis process even in symmetric structures.