This study examines the dynamic response of two adjacent 9- and 20-story benchmark steel buildings subjected to six near-fault earthquake records. Two-dimensional numerical models were employed to account for the complexities of structure-soil-structure interaction (SSSI). The research focuses on the separation gap between the buildings and the effects of pounding while considering Fixed Base (FB) and SSSI models, evaluated according to UBC 94 and ASCE 7–16 seismic codes. Key findings reveal that pounding occurs with the UBC 94 separation gap when earthquake frequency aligns with system frequency, leading to increased column stresses in the 9-story building. In contrast, the ASCE 7–16 standard effectively prevents pounding in both the FB and SSSI models. Additionally, drifts and displacements of lower floors in SSSI models exceed the allowable limits of ASCE 7-16, underscoring the impact of soil-structure interaction on seismic response.
