Rapid Damage Detection in Buildings Through ARMAX Analysis of Wind Induced Vibrations

Abstract

After a seismic event, it is imperative that critical structural members that are damaged within a building are identified and analyzed as soon as possible to ensure proper remedial measures can be taken. Failure to detect damage or correctly analyze the severity of damage within the building could have catastrophic consequences. When a reinforced concrete building is subjected to a damaging event, the standard method for identifying and analyzing structural damage currently involves extensive surface-level visual inspections which often result in inconclusive and inconsistent damage analysis. Structural Health Monitoring (SHM) is a rapidly developing field which is vastly improving the way damage is assessed within buildings and other major infrastructure. In this thesis, an automated SHM Damage Detection Model (DDM), specifically tailored for buildings, is developed that uses time series analysis along with sensor clustering techniques to detect damage in a building from its vibration response due to ambient wind loading. The specific time series analysis methodology used throughout this thesis is an Auto-Regressive Moving Average model with eXogenous inputs (ARMAX). To validate the ARMAX DDM, a detailed wind simulation model that applies forces based on actual wind behaviour is created along with a numerical damage model applicable to reinforced concrete buildings. To evaluate the effectiveness of the proposed DDM in locating and quantifying damage at storey-level precision, six different buildings are modelled in SAP2000. The results from the numerical modelling proved the effectiveness of the ARMAX DDM at accurately locating and quantifying the degree of damage from wind induced floor vibrations at storey-level precision. The limitations of the DDM in its current state and recommendations for future work are discussed to conclude the thesis.