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The city growth and development with all the dynamics are currently going on quite rapidly demand, the provision of facilities and city infrastructure is getting better and more adequate. Urban infrastructure development, especially those related to waste management, is an urgent need in the context of efforts to prevent environmental pollutions. Several factors need to be considered to building infrastructure, one of which is the security factor. The safety factor is a major factor in the construction of the retaining wall. The purpose of this study is to investigate mechanical effects of soil retaining wall in the three types of designs of the landfills by 2D finite element analysis. The results could provide a reference for building to withstand the active lateral compressive forces of soil and water. The contribution of this study is sufficient for providing a functional strength of retaining walls. FEM (Finite Element Method) is a numerical method that is often used in analysing the compressive strength of retaining wall. In this study, 2D analysis is used to determine the compressive strength of the soil on the retaining wall of the landfill in Manokwari City. The retaining wall in this study is varied based on these three forms of the retaining wall. It is according to the literature and the three different finite element numbers based on the software. Ansys software is used to simulate the compressive strength of retaining walls against the ground. The results found were compared. The results obtained indicated that the geometry design 2 has a better safety value when compared to the others. This is reinforced by the results of the numerical calculations obtained, namely A2 = 29497.3 N/mm2, B2 = 42579.2 N/mm2, and C2 = 82138.8 N/mm2.

Selective laser sintering (SLS) is an important additive manufacturing method for polymers and is increasingly used for industrial applications. To improve the quality of printed products a thorough understanding of the process is necessary. Simulations are a convenient way to assess the sintering in detail. In literature several numerical studies can be found on the sintering process of two particles. Both 2D and 3D geometries are used and sometimes the assumption of axisymmetry is made. If the effect of the laser beam in temperature-dependent sintering is taken into account, axisymmetry cannot be assumed anymore and full 3D simulations are required. However, these simulations are complex and computationally expensive. In this work, we assess if 2D simulations are representative for the 3D case of the temperature-dependent sintering process of two viscous particles. We find that 2D simulations are a good alternative for 3D simulations for the sintering problem of two particles, if the correct geometrical scaling factors are taken into account.

The disposal of waste tyres in a landfill has been outlawed in Europe since 2000, with some exceptions being made for construction works. Since then, tyre-derived products have been widely used in road applications. One of these applications is in tyre bales, comprising 100–140 car vehicle tyres compressed into a lightweight block and secured by galvanised steel tie wires running around the length and depth of the bale. In the scope of the project reported here, the authors conducted comprehensive laboratory and field tests on applying tyre bales and shreds as a backfill to integral bridges. In this paper, a full-scale experiment is described in which the pressure of a tyre-baled backfill supplemented with medium sand filling and a tyre shreds buffer layer has been evaluated. The experiment was prepared and conducted by means of a special full-scale trial built to simulate real bridge abutment conditions. Test results clearly revealed the efficiency of the backfill composed of tyre bales, tyre shreds and medium sand filling in terms of pressure reduction on a bridge abutment in comparison with pressure distribution of homogeneous soil pressure. A finite element 2D analysis was also conducted to model the behaviour of a waste tyre/sand backfill. Since there was pretty good agreement between numerical and experimental results, the validated FE analysis might be reliably adopted in further design for a sustainable bridge solution. The first Polish application of the abutment backfill from waste tyres has been briefly described as well.

Pressure ulcers occur due to sustained mechanical loading. Deep tissue injury is a severe type of pressure ulcer, which is believed to originate in subcutaneous tissues adjacent to bony prominences. In previous experimental-numerical studies the relationship between internal tissue state and damage development was investigated using a 2D analysis. However, recent studies suggest that a local analysis is not sufficient. In the present study we developed a method to create animal-specific 3D finite element models of an indentation test on the tibialis anterior muscle of rats based on MRI data. A detailed description on how the animal specific models are created is given. Furthermore, two indenter geometries are compared and the influence of errors in determining the indenter orientation on the resulting internal strain distribution in a defined volume of tissue was investigated. We conclude that with a spherically-shaped indenter errors in estimating the indenter orientation do not unduly influence the results of the simulation.

Efficient and versatile BEM-FEM coupling procedures are discussed.Nonlinear and non-matching adaptive analyses are considered.Optimized and unified iterative approaches are employed. In this work, two iterative BEM-FEM coupling procedures are discussed, taking into account nonlinear models and adaptive spatial discretizations. In both procedures, optimal relaxation parameters are computed (speeding up the convergence of the iterative coupling) and non-matching discretizations at common interfaces are allowed (enabling more versatile adaptive approaches). A single unified iterative loop is considered in order to deal with all the focused iterative solutions simultaneously (i.e., nonlinear analysis, adaptive analysis and coupling analysis), rendering a very efficient methodology. At the end of the paper, numerical results are presented, illustrating the good performance of the proposed technique.

Lumbar interbody fusion is currently the gold standard in treating patients with disc degeneration or segmental instability. Despite it having been used for several decades, the non-union rate remains high. A failed fusion is frequently attributed to an inadequate mechanical environment after instrumentation. Finite element (FE) models can provide insights into the mechanics of the fusion process. Previous fusion simulations using FE models showed that the geometries and material of the cage can greatly influence the fusion outcome. However, these studies used axisymmetric models which lacked realistic spinal geometries. Therefore, different modeling approaches were evaluated to understand the bone-formation process. Three FE models of the lumbar motion segment (L4–L5) were developed: 2D, Sym-3D and Nonsym-3D. The fusion process based on existing mechano-regulation algorithms using the FE simulations to evaluate the mechanical environment was then integrated into these models. In addition, the influence of different lordotic angles (5, 10 and 15°) was investigated. The volume of newly formed bone, the axial stiffness of the whole segment and bone distribution inside and surrounding the cage were evaluated. In contrast to the Nonsym-3D, the 2D and Sym-3D models predicted excessive bone formation prior to bridging (peak values with 36 and 9% higher than in equilibrium, respectively). The 3D models predicted a more uniform bone distribution compared to the 2D model. The current results demonstrate the crucial role of the realistic 3D geometry of the lumbar motion segment in predicting bone formation after lumbar spinal fusion.

A combined ground-improvement method has recently been adopted for embankments on soft soil that involves the use of both deep mixed (DM) columns and prefabricated vertical drains (PVDs) to increase the bearing capacity and accelerate the consolidation of the soft soil. A well-instrumented embankment was constructed in a field using this ground-improvement method to verify its performance. Three- (3D) and two-dimensional (2D) finite-element analyses were conducted to evaluate the performance of an embankment constructed over soft soil improved by the DM columns and PVDs. In the 2D analysis, a plane-strain conversion method was used to simulate the 3D condition. The finite-element software ABAQUS was used for these analyses. The computed settlements, excess pore-water pressure, load transfer from the surrounding soil to the columns, and lateral displacements in both analyses are compared with the field data, and good agreement was found between the computed and measured data. The field and numerica...

A mesh partition based explicit integration method for dynamic structure FEA is proposed in this article. With this method, the whole finite element mesh is partitioned into several zones according to the elements increment feature size, and then variable time increments are applied to the mesh zones for explicit integration while the parameter transfer and interpolation is performed over the interfaces to ensure the continuity. This method has the capability of boost the analysis efficiency without much precision loss to the analysis results of interested zones, which is proven by some 2D analysis examples.

This paper deals with the characteristic analysis of small power brushless DC (BLDC) motor considering the rotor magnet overhang flux. In the driving characteristics analysis using 2D FEA (Finite Element Analysis), the rotor magnet overhang effect can't be considered and it should be neglected. To consider rotor magnet overhang effect, 3D FEA should be required. But 3D FEA requires very long calculation time even though the high specification computer is used. In this paper, the 3D electromagnetic model of BLDC motor is approximated as the 2D electromagnetic model considering overhang effect. In this paper, the concept of overhang coefficient is applied, and the coefficient according to load torque variance is deduced.

In this paper, we present an analysis of a two-dimensional electric circuit-electromagnetic field coupled problem using the wavelet-Galerkin method. For illustration, the bar-plate configuration, a basic model for analysing eddy cur rent phenomenon in electrical apparatus, is chosen. Firstly, a brief description of wavelet theory and its application in co mputational electromagnetics is provided. Then, a description of the two-dimensional coupled problem formulation and its solution using the wavelet-Galerkin method is given. Finally, results obt ained using simulation are presented.

A new a posteriori error estimate for finite element stress analysis is proposed. This engineering approach is characterized by using local reference systems that allows establishing which stress components must be continuous and which may not be continuous at interfaces between two elements. It is shown that, for a 3D analysis, only three stress components are sufficient to evaluate the stress error, and for a 2D analysis only two stress components are needed. Some 2D examples are considered and excellent results are obtained for both homogenous and heterogeneous materials.

Foundation is a critical element for any dam. Understanding the foundation and the required treatment is critical to developing the final dam design. However, the design of the foundation does not end with the final design drawings for the Project. During construction foundation conditions need to be evaluated as excavation and construction proceeds to determine if foundation conditions are consistent with assumptions and expectations. Adjustments to the planned excavation or to the design of the dam, including changes in the grout curtain, dam geometry, and other features are often required during construction. This paper discusses the foundation conditions encountered during construction of concrete gravity dam and the associated treatments that were required. To ensure the safety of project, foundation was treated and design adjustments were made. A 2D analysis was carried out using ABAQUS Finite Element Method (FEM) software.

In a previous 2D parametric study, it was found that the die size appear to have no significant effect on the likelihood of delamination at the pad-encapsulant interface in a plastic-encapsulated IC package. This trend appears to be counter intuitive since in practice, it is known that larger dies are more likely to delaminate in comparison with smaller ones. The authors had speculated that this could be due to the limitations of 2D analysis. Hence this finding is re-investigated using 3D analysis. In this parametric study, 3D finite element models that incorporate an initial delamination a corner delamination of different shapes (concave, convex, straight) were analyzed. The geometric parameters varied include the size of the pad, the die and the package. Both the energy release rate and mode mixity were calculated. It was found that in 3D analysis, different shapes of initial delaminations result in similar trends in the propensity to delaminate from the corners. From the results of the 3D analyses of a package with an initial corner delamination, it was found that increasing the die size leads to an increase in ERR, and hence an increase in the likelihood of delamination from the corners of a package. This trend is in contrast to that predicted from the 2D analyses, that ERR do not increase with increasing die sizes. The above findings seem to suggest that for predicting delamination from the corners of a package, which is usually where the highest stress is located, only a 3D analysis will be adequate.

A 2D analysis of the deformation process in the rolling gap is presented. Flat strip rolling is considered for a low carbon steel at a temperature of 1000°C. 2D — Finite Element models with a rotating workroll have been installed using the Abaqus/Explicit-Code. The workroll is modelled as a rigid body. The main subject of the analysis is to show the influence of the phenomena taking place at the entrance to the rolling gap on the development of the stress and the strain fields in the rolled material. It can be shown that due to the shearing process the backward slip exists of the three zones A, B, C. The importance of these zones depends strongly on the shape coefficient Δ. The elastic — plastic modelling of the material behaviour allows the calculation of the residual stresses.

LGEP 2010 ID = 636; International audience; This paper presents a 3D numerical model of magnetoelectric sensors based on the finite element method. It is obtained using the association of magnetoelastic and piezoelectric behaviour laws. The 3D finite element formulation is evaluated on a bi-layer beam, combining magnetostrictive and piezoelectric materials, submitted to magnetic fields. These results are compared to the ones obtained with a validated 2D finite element model. At last, a cylindrical magnetoelectric sensor, which can not be modelled with a 2D analysis, is evaluated.

In this study a rotational single sheet tester is simulated using a 2D finite element software Flux2D. Its main goal is to find the best geometrical structure of the device which reaches the largest homogeneity of the magnetic field in the sheet plane. This imposes the size of the sheet area in which the measurements have to be achieved. The simulations have been performed using the magnetic vector potential A formulation and have been limited to a magnetostatic case. The results point out that the square shaped specimen is the best one. The influence of the yokes width is also shown and discussed.

The presence of a very thin layer of material whose permeability differs significantly from that of the surrounding soil can impose the adoption of a very dense finite element mesh, because of the small element dimensions required for the modeling of the thin layer. This paper presents the formulation of an isoparametric thin-layer element for 2D analysis which can be employed with advantage for the modeling of such zones, allowing for greater economy in mesh development and analysis time, while at the same time providing accurate results. The proposed thin-layer element is derived from a quadrilateral element by making one dimension converge to zero and it can handle flow in both the normal and tangential directions.

Comparison of the results of 3-dimensional (3D) and 2-dimensional (2D) finite element analyses (FEA) shows that the 2D analysis is accurate enough for calculating the shape factor for narrow sandwich seals and is considerably less expensive. The 2D analysis confirms the accuracy of an earlier approximate theoretical solution, particularly for seals with skin-to-core thickness ratios of 0.5 to 2. For seals with extremely thin or thick skin the use of 2D FEA is recommended. The FEA results show that the shape factor does not change appreciably either with the modulus ratio, Es/Ec, or with the composite Poisson's ratio, v, although it has a marked dependence on the aspect ratio of the core layer. Experimental values of the shape factor show fairly good agreement among theory, FEA, and experiment and provide confidence in the proposed theory and the 2D FEA.