عنوان مقاله [English]
Earthquake accelerograms, recorded in near-fault areas, indicate severe vertical ground motion. The near-fault earthquakes, due to their destructive effects, are distinguished from the far-fault ones. The importance of this issue will be more noticeable in case of long span frames. The use of long span frames, in addition to making it possible to have open areas in buildings, can help the creation of more beautiful architectural spaces. However, these frames are highly vulnerable subjected to earthquake. In this study the effect of vertical earthquake component on the long-span frames is investigated by modeling two structures with different spans, and using Sap and Perform software. First, the structures are analyzed under the effect of horizontal earthquake components and the values of moment, shear, and axial force of columns, as well as mid-span deflection of long span beams are obtained. In the next stage, the vertical earthquake component is added to the input, and the abovementioned responses are obtained again. By comparison, it is concluded that the vertical earthquake component has a very increasing effect on the mentioned structural responses.