Broadband physics-based earthquake simulations are used to study the characteristics of near-fault ground motions and their impacts on building structures. The study focuses on two aspects of near-fault ground motion: (1) strong double-sided velocity pulses which are induced by forward rupture directivity effects, and (2) single-sided velocity pulses accompanying the permanent ground offset near the fault, which are known as fling step. The study examines the characteristics and impacts of both of these phenomena on engineering demand parameters, and assesses the need for explicitly incorporating them in the selection of representative ground motion records for nonlinear analysis of near-fault structures. The performance of simulated earthquake ground motions is compared against real records in a scenario-based seismic analysis context. Based on the findings of the study, guidance on using physics-based earthquake simulations in performance-based seismic engineering applications is developed, and opportunities for future improvements of earthquake simulations and near-fault ground motion selection procedures are highlighted.