###### Abstract  
This study was based on a target spectrum (GB183062015) and synthesized different characteristic periods, pulse ground motions, and non-pulse ground motions utilizing EQsignal v1.2.1 software. It also investigated the dynamic behaviors of bridge pairs in seismic motions with varying characteristic periods, pulse and non-pulse effects, and the influence of 0 m and 10 m water depths. The findings indicated that the peak acceleration and stress behaviors vary significantly under different characteristic periods of ground motion. The maximum error in peak acceleration behavior of a bridge pier under ground motions of varying characteristic periods is 19.25%, while the maximum error in peak stress response is 11.35%. The acceleration and stress behaviors of a bridge pier under pulse ground motion action are more considerable than those under non-pulse seismic motion action. When the characteristic period is 0.40 s, the maximum error in peak acceleration of the bridge pier structure under pulse seismic motion and non-pulse seismic motion action is 86.08%, with the maximum error of the peak stress reaches 80.68%. The existence of water serves to minimize the natural frequency of the bridge pier. The pulse effects result in a maximum error of 40.49% for the peak acceleration and a maximum discrepancy of 323.08% for the peak stress of the bridge pier. The hydrodynamic effects result in a maximum error of 33.51% for the acceleration peak and 12.90% for the stress peak of the bridge pier. The effect of the pulse symptoms on the dynamic behavior of the bridge pier is considerably more pronounced than that of the hydrodynamic effects, with an intricate and complex influencing mechanism. In bridge flood protection and seismic design and optimization, it is essential to consider the impact of pulse seismic motion with varying characteristic periods. b 2024 14 10709 10.3390/APPL142210709 12 October 2024 16 November 2024 18 November 2024 18 November 2024 19 November 2  
the simplified hydrodynamic pressure expression [4], effective calculation methods [5; 6], and so forth. [PERSON] et al. [7] studied the seismic presentation of sea-crossing bridges and found that the size of the pier structure has a striking on the hydrodynamic force of the bridge. [PERSON] et al. [8] integrated the hydrodynamic effect caused by earthquakes into the new evaluation method and studied the influence of strong coupling caused by hydrodynamic pressure and structural flexibility changes on the seismic performance of the structure. [PERSON] et al. [9] proposed a correction approach for the calculation of added mass based on the dress of the added mass coefficient, and studied the influence of the added mass of a bridge structure on the hydrodynamics. [PERSON] et al. [10] examined the effects of hydrodynamic forces on the dynamic behavior of deep-water bridge piers by using displacement and internal force influence coefficients. Their findings verified that the coefficients accurately predict structural behavior, offering valuable tools for assessing the property of water flow on bridge pier stability in dynamic conditions. In comparison to non-pulse seismic waves, pulse ground motion causes more serious damage to a structure. Consequently, a greater number of scholars have examined the dynamic response of pulse seismic motion action to structures. For the influence of pulse ground motions, some structures may require measures such as strengthening steel bars to control displacement and other responses [11]. In light of the corroboration of the impact of pulse seismic motion through observational evidence, it is imperative to accord due consideration to the influence of pulse seismic motion when evaluating the seismic resilience of structures [12]. The characteristic period affects the magnitude, acceleration, velocity, and other parameters of the pulse seismic motion. The striking of the characteristic period on the structural behavior is discrete [13]. [PERSON] et al.