PSI - Issue 41

Abdoullah Namdar et al. / Procedia Structural Integrity 41 (2022) 403–411 Author name / Structural Integrity Procedia 00 (2019) 000–000

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deformation and displacement, and to improve embankment-subsoil seismic stability, and the statistical models are developed for interpretation, predication, and comparing the results of the numerical simulation. 2. Method for simulation It well knowns that the seismic resistance of the embankment-subsoil is changing with strengthening the shear strength of the subsoil. The geogrid-soil interaction and finding the best place to improve the strength and stiffness of the model need to investigate by using the nonlinear finite element method. To estimate embankment-subsoil nonlinear deformation and displacement through the reinforcing subsoil the numerical simulation was performed. Table 1 illustrates the mechanical properties of the soil and the steel (A36M). The mechanical properties of the soil are the modulus elasticity of 24 (MPa), friction angle of 40 (deg), dilatancy angle of 2 (deg), the cohesion of 17 (kPa), unit weight of 18.5 (kN/m 3 ), and Poisson’s ratio of 0.2 (Valleti et al., 2018). The important mechanical properties of the steel used in the numerical simulation are modulus elasticity of 200,000 (MPa), Poisson’s ratio of 0.3, shear modulus of 77,000 (MPa), and yield stress of 250 (MPa) (AISC, 2009). In the ABAQUS finite elements software, the steel bar was used for the assembly of the geogrid, and finally the geogrid was embedded in the different locations of the subsoil. In the ABAQUS FE software, soil-steel interaction was simulated using the nonlinear numerical simulation. The geogrid embedded in the soil was proposed to improve the shear strength of the soil and enhance the subsoil for nonlinear acceleration mitigation. Figure 1 depicts the seismic acceleration was applied to the model. The seismic acceleration collected from the literature (CESMD), and applying seismic acceleration on the model supports to realizing the embankment-subsoil seismic response. The statistical techniques proposed for considering the geogrid impact on nonlinear deformation and displacement of the model when the subsoil is reinforcing in a different location. For statistical modeling, the data were collected from the several stages of the numerical simulation. The results of the nonlinear numerical simulation in the loading stages were used for identifying the best location to install geogrid.

Norcia Earthquake with 6.2 magnitude (24 August 2016).

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Characteristics of acceleration at Z direction

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Fig. 1. Seismic acceleration physiognomies subjecting to the embankment-subsoil [CESMD].

To simulate the nonlinear displacement of the embankment-subsoil model, according to the report in the literature (Namdar, 2021b), all stages of the numerical simulation have been used. The simulation of the nonlinear