PSI - Issue 39

Abdoullah Namdar / Procedia Structural Integrity 39 (2022) 57–64 Author name / Structural Integrity Procedia 00 (2019) 000–000

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1. Introduction The seismic failure of an earth structure has several reasons such as the inadequate bearing capacity of the soil, high nonlinear vibration of the soil, unallowable linear and differential settlement, and undesirable deformation, among these reasons the crack developing on soil is very important for seismic stability design of an earth structure and needs suitable exploration. Nomenclature Cracked zone Solid zone Earth pressure at beneath Earth pressure at the top E Modulus elasticity ϕ Friction angle ψ Dilatancy angle C Cohesion γ Unit weight ν Poisson’s ratio The soil bearing capacity variation using analytical method investigated concerning mixed soil parameters and change footing dimensions. (Namdar et al., 2014). The impact of the mechanical properties of the soil on the bearing capacity of the soil foundation was studied (Namdar et al., 2009). The mixing soil and modification of concrete footing dimensions are modifying the mechanical properties of the soil. It is well known with the high level of the soil bearing capacity still is the possibility of the cracking of the soil. The cracking of some part of the soil leads to the reducing bearing capacity of the soil. It needs to study the influence of the crack developing of soil on the displacement mechanism of the soil. It has been described the impact of the cracking of the several types of materials under biaxial loading (Namdar, 2021) static and nonlinear loading (Namdar et al., 2016). There is damage and microstructure crack path reporting due to fatigue (Iacoviello et al., 2005; Iacoviello et al., 2013; Iacoviello et al., 2014). The clay soil, in the backfill parts, has a crack zone due to applied static load. Further investigation is requiring basis on applying dynamic load on soil clay when the crack initiating on the soil because of the mechanical properties of the clay and geometry of the infrastructure, which causes failure of earth structure due to the development of the crack zone area. The crack zone may be starting from the backfill zone and extending to the other parts of the structures. Applying nonlinear cyclic loading on the material creates the nonlinear strain energy (Branco et al., 2019), and the nonlinear strain energy accelerates the fatigue on the materials (Susmel et al., 2019). Additionally, the nonlinear displacement of the substructure is associated with the nature of the loading is applied to the model (Namdar, 2021a), also the boundary condition of the model significantly enhancing the level of results accuracy (Namdar, 2021b). Using linear regression analysis and artificial neural networking were showed improving geotechnical engineering design, the prediction results showed the successful application of the mixing soil technique for improving soil stability in the point view of economic and acceptable design accuracy (Namdar, 2020a; Namdar, 2020b). The fatigue, damage, failure mechanism, and strain energy density have been predicted (Albinmousa et al., 2020; Marsavina et al., 2019; Foti et al., 2018). The results of numerical simulation, analytical method, and experimental laboratory research works are requiring for interpretation and verification. The soil and earth structure have a very complicated loads response. Geotechnical engineering similar to the other parts of science and technology needs more prediction in the experimental, analytical, and numerical investigation. In general, the low tensile strength of soil is the main factor in initiating and accelerate a crack. In this study, the impact of soil crack on backfill seismic stability is simulated. At the analytical method, the cohesion and density of the clayey soil are the main parameters for calculating the thickness of the crack zone. To realizing the displacement mechanism on a cracked backfill, the nonlinear finite element method (NFEM) needs performing, for verifying the