Nonlinear ground performance under a high shaking scenario similar to Boumerdes earthquake

Abstract. This paper studies the ground response at the Dar El Beida site in Algiers, Algeria, under a strong earthquake scenario equivalent to the Boumerdes earthquake using FLAC2D software. The input motion's two horizontal components (EW, NS) and vertical component (V) are applied independently at the bedrock level. By comparing numerical predictions with recorded data, we can assess the performance of nonlinear analysis compared with the equivalent traditional linear approach. Furthermore, the nonlinear response spectrum takes into account the nonlinear behavior of materials and structures, which is crucial when analyzing structures that may undergo significant deformations during an earthquake. This type of spectrum is particularly relevant for ductile structures, which can undergo plastic deformation under heavy loads. The first simulation of this communication is carried out by DEEPSOIL software, which implements equivalent linear and nonlinear procedures; the results show good agreement in terms of acceleration. The second simulation was carried out by FLAC2D software using the Ramberg-Osgood model limited by the Mohr-Coulomb criterion. The examination focuses on the first 30 meters of soil. This depth is crucial for determining the dynamic behavior of the soil during seismic occurrences. The Ramberg-Osgood model limited by the Mohr-Coulomb criterion used in the nonlinear analysis is quite good at predicting ground motion.