Abstract Summary
In this paper, a flexible strain sensing system for full-scale RC frame structures is presented. The system includes two flexible strain gauges in different configurations, a single full-bridge and a double half-bridge. It also includes a selector that can be switched between measuring axial and bending strains depending on where the sensor is mounted. The first part mainly introduces the development process of the flexible strain system, which is mainly designed to measure the requirement of strain field abnormality caused by structural damage. Then the development of a strain switching selector is introduced, which can switch two different strain measurements according to requirements without changing the sensor installation location and identify any anomalies as structural damage. To verify the sensitivity and performance of the flexible strain sensing system, sensors of both configurations were installed on the beams and columns of a full-size concrete frame structure, and cyclic loads were applied to them to measure the strain trend of critical elements. 14 LVDTs were also installed for monitoring the displacement changes of the structural model. The experimental results show that the flexible strain sensing sheet has high stretchability and sensitivity and can well monitor the strain trend of the full-scale frame model, it also can be used as an integrated Structural Health Monitoring (SHM) system to monitor the strain of local structural damage.
