Dynamic time-history analysis of prefabricated shear wall structures with unconnected vertical distribution reinforcement

Unconnected vertically distributed reinforcement (SGBL) detailing offers convenient construction and simplified connections; however, the dynamic response and frequency-domain characteristics of the complete structural system under different ground motions remain insufficiently understood. In this study, a two-story SGBL prefabricated monolithic shear-wall structure was designed, and a refined finite element model was developed in ABAQUS. The material constitutive laws, interface relationships, and connection modeling method were first validated against published quasi-static tests on prefabricated shear walls, with errors in the predicted peak load-carrying capacity below 10%. Nonlinear dynamic time-history analyses were then conducted using a fitted artificial seismic wave, the EL-Centro record, and the Taft record under Intensity 7 frequent, Intensity 8 frequent, Intensity 7 rare, and Intensity 8 rare earthquake levels. Fourier spectra and power spectral density (PSD) were further examined to characterize the frequency content of the ground motions. The results show that ground-motion intensity is the primary factor controlling the global dynamic response. Top acceleration, Roof displacement, storey drift ratio, and base shear all increased markedly with seismic intensity. At the same seismic level, the fitted artificial seismic wave generally produced the largest Top acceleration and Roof displacement, followed by the EL-Centro and Taft records, whereas the peak base-shear values generated by the three motions were similar. Under the Intensity 8 rare earthquake, the maximum Roof displacement was 30.55 mm, the maximum storey drift ratio reached approximately 80% of the 1/120 limit, the second storey controlled the deformation response, and the mean peak base shear from the three ground motions was 375.15 kN. More than 74% of the energy of all three motions was concentrated within 0–5 Hz. The structural natural frequency was 4.7 Hz and did not substantially overlap the principal peak-frequency range of approximately 0.5–2.3 Hz. Under the selected ground motions and modeling assumptions, the risk of strong global resonance was relatively low; nevertheless, damage control remains important at the wall base, unconnected joints, opening edges, boundary elements, and other locally vulnerable regions. These findings provide a basis for the seismic design, connection-detail optimization, and local damage control of multistory SGBL prefabricated shear-wall structures.