Inclusion of the vertical seismic acceleration in one-story buildings analysis

The principal parameters that control the elastic behavior of one-story reinforced concrete building models are analyzed in this paper. Models are subjected to seismic ground motions considering the action of the thee-recorded ground accelerations,Ü_x,Ü_y, and Ü_z,. The horizontal components, Ü_x,Ü_y, are considered acting in a critical angle of incidence determined for each analyzed model. This effect has been thoroughly studied in previous works. The influence of the vertical ground acceleration on the seismic response has not been exhaustively studied. Adequate and simple methods to consider the combined effects of the thee ground motion components for seismic design are proposed in this work. Three-dimensional one-story models, characterized by parameters as the lateral period of vibration, the lateral-transverse period ratio and the lateral-torsional period ratio, the vertical period, the slenderness of the corner columns, the eccentricity, the aspect ratio of the plan, the beam-column stiffbess ratio, and the border conditions of the floor slab, are studied. Seismic responses are obtained using a time history response analysis method. Models are subjected to different ground motions. The compatibility of vertical deformations is enforced, and the transversal and torsional stiffhesses of the elements are considered. Maximum local and global responses are studied. The responses of vertically flexible models are especially affected by the inclusion of vertical ground acceleration. It should be considered in the seismic design. Additionally, a diaphragm behaves like a floor slab under vertical cyclic loads. It doesn't act like a rigid body in the vertical direction, particularly if its dimensions are large.