Wave Method for Structural Health Monitoring: Testing Using Full-Scale Shake Table Experiment Data

Abstract

An algorithm of the wave method for structural health monitoring (SHM) is tested and calibrated using shake table experiment data of a full-scale, seven-story, reinforced-concrete building slice. The method is based on monitoring changes in the velocity of waves propagating vertically through the structure, identified by least-squares (LSQ) fit of beam models. The experiment was conducted by a team from the University of California, San Diego (UCSD) on the Network for Earthquake Engineering Simulations (NEES) outdoor shake table. Ambient noise, white noise, and earthquake response data for four progressive damage states were analyzed. The algorithm is tested for the first time on highly dispersive wave propagation, on a damaged structure, and on much shorter segments of ambient vibration data than used previously. The structure is modeled as a Timoshenko beam with large shear stiffness, and its compressional wave velocity, cL, is identified. The change in cL is measured for the different damage states and is compared with the change of the fundamental frequency of vibration, f1. The effectiveness of the method is discussed.