The purpose of this paper is to investigate the effect of vertical ground motion input on horizontal seismic responses of two-story wooden houses with sliding base systems. The two-dimensional frame model of a two-story wooden house was developed in OpenSees, and time history response analysis was conducted with/without vertical ground motion input. The maximum sliding displacement increased by 10 cm due to the decrease of friction force at a sliding base caused by vertical ground motion. The story drift angle and horizontal acceleration of the superstructure increased when the strong vertical ground motion inputted during the sliding motion.
