Structural Functionality Evaluation Based on Natural Frequency Measurement.

A method to calculate structural functionality for building structures based on structural natural frequency was proposed for seismic loading events. Structural functionality loss and recovery were determined by monitoring the change of structural natural frequency during the earthquake events or repair activities. A shape factor was introduced, structural functionality recovery function (SFRF), to consider the repair strategy and repair speed. As an example, this method was applied to obtain the structural functionality curve and seismic resilience of a half scale two-story reinforced concrete (RC) frame structure. This structure was subjected to a series of ground motions on a shake table and then repaired by carbon fiber cloth a total of four times. The results indicate that the SFRF is able to capture the recovery trend of a structure in the repair process. Meanwhile, a damage index-repair target (DI-RT) curve, representing the 5% difference between the proposed and traditional SFRFs, was used to investigate the impact of structural damage degree and repair target. The areas above the curve indicates that the difference between the proposed and traditional SFRFs cannot be ignored. [ABSTRACT FROM AUTHOR]