A 2D numerical analysis by using the Finite Elements Method of the Modeling Methods of Closed Shield Tunneling and the Surface Subsidence induced by that

In this paper, the modeling methods of tunneling and the surface subsidence induced by that have been studied by using two-dimensional numerical analysis according to the FEM method, assuming the green field condition، which means that there is no load on the soil surface above the tunnel. A FE study was conducted in which an elasto-plastic constitutive model was adopted to model the soil behavior (HS, HSsmall). This article includes a comparison between the results of numerical analysis and field measurements to executed projects، and a suggested method for modeling tunnel excavation and surface subsidence induced by that.

Numerical Analysis and Model tests of the Bearing Capacity of shallow Strip Footing resting on Multi-layered Soils

In present investigation attempt has been made to study the bearing capacity and settlement characteristics of footings subjected to central vertical load and resting on layered soil with the help of model tests and with the application of finite element method (FEM) to calculate bearing capacity of a strip footing on one-layer and two-layer soil (Sand and Clay). To investigate the effect of various parameters on soil bearing Capacity a commercial finite element software, PLAXIS, has been used. Soil profile contains two soil types including sand and clay. Soil behavior is represented by the elasto-plastic Mohrcoulomb (MC) -model. For a one-layer case, the bearing capacity also is calculated which has a good agreement with theoretical equations. For a layered soil, soft-over strong soil, parametric study was carried out. It is concluded that the bearing capacity of footing decreases as the height of clayey soil increases whilst the displacement under footing increases. There is a critical depth where the stronger bottom layer does not affect ultimate bearing capacity and failure mechanism of footing.

Numerical Analysis on Performance of strip footing on Clay Soil reinforced with Geogrid bags

This research study aims at investigating the potential benefits of using the reinforcement to improve the bearing capacity and reduce the settlement of strip footing on clay. To implement this objective, many numerical 2D-analyses by finite element method / Plaxis program were performed to study the behavior of reinforced soil foundation. And then we carry out a parametric study of the most effective parameter on bearing capacity. The results showed that the inclusion of reinforcement can significantly improve the bearing capacity and reduce the footing settlement. The strain developed along the reinforcement is directly related to the settlement. The results also showed that the inclusion of reinforcement can redistribute the applied load to a wider area, thus minimizing stress concentration and achieving a more uniform stress distribution. The redistribution of stresses below the reinforced zone can result in reducing the settlement of the underlying weak clayey soil.

Behavior of Steel Frame with Thin Steel Infill Plate or Steel Bracing Under Cyclic Loading-Comparative Study

Braced frames and steel plate shear walls (SPSWs) have both been shown to be useful in the seismic retrofit of buildings. While both these systems have merit, no guidance exists to determine which of the two approaches is preferable in terms of providing maximum displacement ductility and energy dissipation per cycle for a given strength. This paper describes and compares results from numerical evaluation using FEM, in which the nonlinearity of materials and the nonlinear effects of the large displacement was included for tow frames. The results of numerical study was identical to the experimental tests, then a barometric study was achieved by changing the thickness of infill plate then the area of the cross sections of braces, after that the width of the frame was modified. The result shown that using steel infill plate is preferable when the dimension of bay is three times the height, while using braces is more adequate for frames in which the dimension of bay is less than three times the height.

Evaluation of Modal Pushover Analysis for R.C. Structures

This study has provided an accurate description of the traditional nonlinear static analysis and modal pushover analysis and then these two analyzes applied for a set of concrete buildings.

Numerical Analysis on improvement of Bearing Capacity of Strip footing on reinforced Clay with Geogrid layer

This research study aims at investigating the potential benefits of using the reinforcement to improve the bearing capacity and reduce the settlement of strip footing on clay. To implement this objective, many numerical 2D-analyses by finite element method / Plaxis program were performed to study the behavior of reinforced soil foundation. And then we carry out a parametric study of the most effective parameter on bearing capacity. The results showed that the inclusion of reinforcement can significantly improve the soil’s bearing capacity and reduce the footing settlement. The strain developed along the reinforcement is directly related to the settlement. The results also showed that the inclusion of reinforcement can redistribute the applied load to a wider area, thus minimizing stress concentration and achieving a more uniform stress distribution. The redistribution of stresses below the reinforced zone can result in reducing the settlement of the underlying weak clayey soil.

Design of high selectivity tri-band microstrip BPF using tri-section stepped impedance resonator

In this research, tri-band microstrip band pass filter (BPF) has been designed at frequencies (2.37,3.32 ,5.2)GHz which are located at the domain of WiMAX and WLAN systems’ application by using tri-section stepped impedance resonators TSSIRs with open stub and zero feed line. By changing ratios of impedance of stepped impedance resonator.

3D-FEM-Analysis on the Seismic Behavior of Foundation Piles and Soil Structure Interaction

This research deals with the study of the behavior of piles under the influence of seismic loads through (3D) modeling using FE-Method-program (ABAQUS) with special reference to the most important parameters affecting the displacements and internal forces generated in piles. This study has been completed in two phases: the first phase is a case study of the single Pile (reference case), where a study of the behavior of a single pile assigning structure is modeled with a degree of freedom. The parametric study results show that the presence of structure causes the application of a large load in the upper part of the pile resulting from the impact of inertia dominating the kinetic effect. The forces of inertia increases with the increasing mass of structure, and when the frequency of structure nears the frequency of seismic load. The second phase deals with the study of the situation of the group of piles, where the study handles the effect of a number of piles, piles spacing, and locations on the internal force and displacements generated in the piles. The parametric study results have shown for this phase of this research that an increase the number of piles in the group causes a significant increase of internal forces generated at the top of the pile and a slight decrease for those forces in the central part of the pile, that seismic loads are not distributed equally for all piles, and that corner piles are subject to greater loads while mid. Piles are subject to less load.

Modeling and Simulation of Electromagnetic Fields in Three-Phase Induction Motors Using ANSYS Software

The study of electromagnetism in electrical machines is critical, especially in the field of design, investment and optimal performance. To achieve this, there are many ways in which varying degrees of accuracy . The main aim of this piece of research is to study electromagnetic fields distribution in 3ph-induction machines using computational numerical methods and proper software, because these fields form the basic principle in machine 's work. It has been used the finite element method aided computer to solve magnetic equations (Maxwell equations). The simulation of magnetic field in induction machine performed by ANSYS-software. The paper shows technique for finding the electromagnetic fields distribution in all parts inside 3phinduction machine to get optimal design.