Intensity measure-damage relationship in instrumented school and nearby buildings under near-fault pulse-type ground motions

Abstract

This study presents a rare field-based investigation of the relationship between recorded ground-motion intensity measures (IMs) and observed seismic damage in instrumented school buildings and nearby residential structures subjected to near-fault pulse-type ground motions during the February 2023 Kahramanmaras & cedil; earthquake sequence in T & uuml;rkiye. A total of 26 instrumented reinforced-concrete school buildings, ranging from one to five stories and representing collapse, moderate, and slight damage performance states, were investigated using building-specific strong-motion records obtained from on-site stations. A comprehensive suite of IMs, including peak ground acceleration (PGA), peak ground velocity (PGV), spectral acceleration (Sa), Arias intensity (AI), and significant duration (D5-95), was evaluated and compared with observed structural and nonstructural damage patterns. In addition, the relationships among strong ground motion time histories, seismic energy fluxes, spectral representations (Sa, Sa-Sd, and Sa-Sv), and the observed damage in school buildings and nearby structures were examined. The recorded ground motions exhibited pronounced velocity and displacement pulses, including both single- and multi-pulse characteristics, together with concentrated seismic energy flux. The results indicate that the observed damage in school buildings and nearby structures is associated with the combined influence of multiple IMs, pulse-like characteristics, and structural capacity, underscoring the importance of velocity- and energy-based demand parameters for the seismic assessment of structures subjected to near-fault earthquakes.