Damage identification in a plate structure based on a cross-direction strain measurement method

摘要

Structural strain responses are extensively applied in the field of structural health monitoring (SHM); however, previous studies have focused on the damage identification methods based on strain responses. This paper focuses on measurement technology and proposes a new strain measurement method. Four strain gauges are set in a cross direction on the surface of the structure. Then, the Wheatstone full-bridge connection is used to measure the combined strain of the four strain gauges. The peak picking method is applied to estimate the strain modal shape and frequency of the structure under ambient excitation. The strain mode difference is used as a damage identification index. Finally, clamped plate experiments, including single-damage, multi-damage and damage distance experiments, are successfully implemented. Compared with traditional half-bridge strain measurements, the results show that the cross-direction strain measurement method is more sensitive to minor damage and has higher identification accuracy. (C) 2020 Elsevier Ltd. All rights reserved.