Experimental Seismic Study of Pressurized Fire Sprinkler Piping Systems

Keywords: Nonstructural components, earthquakes, pressurized fire sprinkler piping systems, tee joint connections, numerical models

Abstract: This report presents the results from experimental and numerical studies on pressurized fire sprinkler piping systems to better clarify the behavior of tee joint connections and fire sprinkler systems under seismic loading. Two test series were carried out at the University at Buffalo. In the first series, 48 tee joint components for sprinkler piping systems were tested under reverse cyclic loading to determine where leakage and/or fracture may occur. In the second group of experiments, the University at Buffalo Nonstructural Components Simulator (UB-NCS) was used to test two-story full-scale fire extinguishing sprinkler piping subsystems. Numerical models were developed and simulations based on the UB-NCS seismic tests were conducted to validate the models. The results showed good agreement in terms of displacement, acceleration, and moment-rotation relation at piping joints. Finally, a hypothetical acute care facility equipped with full-scale fire sprinkler systems was used as an example in the numerical model to develop seismic fragility curves for sprinkler piping systems with floor accelerations as the demand parameter. Incremental Dynamic Analyses were conducted, and fragility curves associated with various performance objectives in terms of pipe leakage were developed.