Seismic evaluation of special steel moment frames subjected to near-field earthquakes with forward directivity by considering soil-structure interaction effects

While the bottom soil of the foundation is supposed to be rigid and the flexibility effect is ignored, the seismic response of the structure is affected by dynamic properties of the structure, and the soil flexibility does not have any effect on the response of the structure. Hence, considering the results obtained by analyses based on the fixed base buildings can lead to the unsafe design of the structure. On the other hand, the proximity of the site to the earthquake production resource causes the most earthquake energy to be reached to the structure as a long-period pulse. Therefore, near-field earthquakes produce many seismic needs so that force the structure to dissipate this input energy with relatively large displacements. Accordingly, the primary objective of the present paper is the determination of the seismic response of the 3, 5 and 8-story steel buildings with special moment frame system and by considering the soil-structure interaction and panel zone modeling as well. The selected records of the near and far-field earthquakes in nonlinear time history analysis have been used, and the response of the structure was compared in both states.