This study investigated the seismic response characteristics of sprinkler piping systems through a comparative analysis of equivalent static and response-spectrum-based dynamic analyses. As a critical nonstructural component for fire safety, the post-earthquake functionality of sprinkler piping systems is essential. However, historical earthquake damage reports indicate that failures are more often associated with excessive displacement and joint disengagement than with material strength exceedance. In this study, a representative sprinkler piping system applied to actual buildings was modeled using a commercial piping stress analysis program. Modal analysis was conducted to identify the natural frequencies and mode shapes of the piping system, and to examine the potential for resonance resulting from the overlap between the system’s dynamic characteristics and dominant seismic frequency ranges. The key response indices, including piping displacement, stress ratios, and seismic brace reaction forces, were evaluated under various static and dynamic load combinations. The results show that the seismic brace reaction forces tend to be larger in the static analysis, whereas the piping displacement and stress responses can increase in the dynamic analysis under certain load combinations. These findings indicate that the seismic response characteristics vary depending on the selected response indices and analysis methods, suggesting that a comprehensive and rational seismic performance evaluation of sprinkler piping systems requires the integrated use of both static and dynamic analyses.
Choi et al. (2026) studied this question.