## 1 Introduction  
Earthquakes are unpredictable natural disasters that occur frequently worldwide. Earthquakes such as the 1989 Loma Prieta Earthquake in the U.S. (MW 6.9), the 1994 Great Hanshin Earthquake in Japan (MW 6.9), the 1995 Chi-Chi Earthquake in Taiwan (MW 7.7), the 2004 Indian Ocean Earthquake and Tsunami (MW 9.2-9.3), and the 2011 Great East Japan Earthquake (MW 9.0-9.1) caused substantial human and material damage [1]. Seismic fragility curves estimate the conditional probability of structural damage based on the response of a building to an earthquake. They are used to assess and predict damage to facilities caused by earthquakes [2, 3, 4]. They estimate the probability of damage to target facilities by considering earthquake intensity measures (IMs), such as peak ground acceleration (PGA) and spectral acceleration, from various ground motion records. This estimation allows for damage assessments of facilities affected by earthquakes [4, 5]. Typically, the characteristics and geographic location of the facility are analyzed to determine the type and number of input ground motions and IMs required. Nonlinear numerical analysis is then performed, and the results are used to generate seismic fragility curves. Determining the number of input ground motions and the type of earthquake intensity to be used in the dynamic numerical analysis of the target facility is crucial at this point [6]. [PERSON] et al. proposed empirical seismic fragility curves using bridge damage data from the 1995 Kobe Earthquake. They also performed nonlinear analysis on typical bridgesin Memphis, U.S., and used the results to present numerical analysis-based seismic fragility curves [4]. [PERSON] suggested a method for deriving effective numerical analysis-based seismic fragility curves using dynamic structural analysis results [7]. [PERSON] et al. derived seismic fragility curves for a 7-span continuous steel box girder bridge and 2 transmission towers (154 kV and 765 kV) by considering 27 ground motions (20 overseas-measured, 3 domestic-measured ground motions, and 4 artificial ground motions), accounting for Korean ground behavior [8]. [PERSON] et al. assessed the seismic fragility of a 15-story non-seismic design reinforced concrete shear wall apartment building, designed in the mid-1980s, using 30 ground motions and evaluating four performance levels [9]. [PERSON] and [PERSON] assessed the seismic fragility of a two-story piloti structure using incremental dynamic analysis (IDA), considering four ground conditions with twenty-eight ground motion pairs based on seven pairs of ground motions [10]. [PERSON] et al. derived seismic fragility curves for 5 performance levels using 33 ground motions for 4 prestressed concrete road bridges in Chile [11]. [PERSON] conducted a seismic fragility analysis for 6- and 16-story reinforced concrete structures. Two-hundred-and-forty synthetic ground motions were generated and used to assess seismic fragility for five damage levels for the Skopje area [12]. [PERSON] and [PERSON] performed seismic fragility analyses for five damage levels on various concrete buildings (2-, 4-, and 9-story) in Greece using 16 ground motions [13]. [PERSON] et al. analyzed seismic fragility for three damage levels on unreinforced masonry buildings (3-, 4-, 5-, and 6-story) using First Order Second Moment, Latin Hypercube Sampling (LHS), Monte Carlo Simulation (MCS) methods, and IDA. They used 20 measured ground motions from the PEER DB and performed seismic fragility analysis by increasing the ground motion magnitude from 0.05 g to 0.8 g in increments of 0.05 g PGA [14]. [PERSON] et al. performed seismic fragility analysis for unreinforced, masonry-reinforced, and composite-reinforced concrete structures using 20 ground motions [15]. This reveals that in many studies related to seismic fragility curves, a wide range of ground motion counts are used for seismic fragility analysis, and no clear definition exists regarding the appropriate number of ground motions. [PERSON] et al.