Cumulative Absolute Velocity as a Local Damage Indicator of Instrumented Structures

Abstract

This paper addresses the critical issue of localized damage detection in structural health monitoring. It evaluates the application of cumulative absolute velocity (CAV) as a local damage indicator for analyzing the acceleration response of a shaking table test specimen as well as real instrumented buildings. A bridge column test specimen instrumented with 18 accelerometers is subjected to increasing six levels of shaking corresponding to different damage states. The CAV analysis of the horizontal response of the accelerometers identified the elevation where damage is located. The vertical CAV analysis not only identified the existence of damage but also located the damage with high precision. This method is subsequently applied to two instrumented buildings damaged during earthquakes. The results show that for the seven-story Van Nuys hotel, the CAV can correctly locate the damage that occurred during the 1994 Northridge earthquake. For the Imperial county services building, the CAV is also able to correctly identify the location of damage. Thus, the presented CAV method enables identifying the onset and location of damage to evaluate the structural integrity.