On the nonlinear behavior of r.c. buildings in near-field areas

The paper shows the results of a nonlinear dynamic analysis performed on a fixed base reinforced concrete 2D frame subject to near-field earthquakes, i.e. seismic motions close to the epicentral area of the fault rupture. In these areas both the acceleration and velocity signals are impulsive-type and, consequently, the response of the structures requires a specific study. The r.c. frame here considered has six levels and two equal spans; it has been designed according to the instructions provided in Eurocode 2 exclusively under gravity loads, the same design as for lots of existing buildings. The nonlinearity of the frame has been assumed with a diffuse plasticity and a fiber modeling has been considered for the structural elements.