Seismic inelastic behavior of two 7 and 17 levels buildings with structural steel frames located in soils transition and soft in Mexico City

The seismic inelastic behavior of two 7 and 17 levels buildings with structural steel frames, located in zones transition (II) and soft (III) in the Mexico City, is been calculated and compared. The dynamic analysis step by step in time dominion is used for the inelastic responses calculations, with the obtained resistances of the modal spectral analysis. For the transition zone the VIVE-EW-85 and ROMA-EW-89 accelerograms are employed, this last one affected by a 3.29 factor that allows to give an approximation of the action that might have occurred during the 1985 earthquake in that specific place in the city. For the soft zone the record SCT-EW-85 is used. It is determined how the seismic inelastic response variation of the structural steel buildings, so much global as local, as long as the vibrations periods of each studied building approach or separate, according to the dominating period of the soil movement.