Applied Element Method Framework for Vibration-Based Condition Assessment

Abstract

The ultimate objective of structural health monitoring (SHM) is to track the progression of natural deterioration and event-driven damage in civil infrastructure to inform maintenance and prevent unforeseen failure. To be meaningful to engineers and maintenance officials, the information from the sensor network must be distilled into actionable measures, preferably in meaningful engineering quantities. This ability to physically quantify structural performance through SHM is particularly attractive within post-hazard environments, as it could be leveraged to inform first responders, inspectors, and owners of potential vulnerabilities within a structure. Although many techniques have been introduced in recent years to detect the presence and location of damage through vibration-based monitoring, a methodical approach for estimating the extent of damage in meaningful engineering quantities remains elusive and largely unproven on full-scale, real-world structures. Furthermore, case studies have been largely limited to traditional causes of damage such as, natural disasters and normal deterioration. This study investigates the use of vibration-based structural identification and damage detection techniques applied to structural evaluation of conventional building components subjected to survivable blast loading. Experimental testing was performed in a full-scale industrial building where a partially-grouted CMU infill wall, precast prestressed double-tee roof, and an interior steel frame were studied in depth. Modal parameter estimates of the infill wall, which is the focus of this paper, as well as the roof and steel frame, were obtained through experimental modal analysis both prior to and after blast testing to establish both baseline and post-damage datasets. As an alternative to finite element model updating, structural identification of the building components tested is currently being pursued through parameter tuning of an applied element model. The Applied Element Method (AEM) has proven to be particularly attractive for analysis of structures under extreme loads and offers several advantages over the finite element method (FEM) for