Influencing Factors of Laws of Bending Force on Railway Bridge

2014 ◽  
Vol 926-930 ◽  
pp. 584-588
Author(s):  
Bao Ru Guo ◽  
Dun Jin Cai ◽  
Ping Wang ◽  
Yi Wen Deng
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Calculation Model ◽  
Railway Bridge ◽  
The Finite Element Method ◽  
Load Range ◽  
Simply Supported ◽  
Railway Line ◽  
Bending Force ◽  
Girder Bridge

Based on the finite element method and the theory of interaction between beam and rail, for girder bridge and the simply supported girder bridge which are common rail continuous bridge as an example, this establishes on railway line - bridge - bridge pier integration calculation model and analyzes the influence of the type of load and load range on the bending force law.

Study on Flexibility of Intracranial Vascular Stents Based on the Finite Element Method

2018 ◽  
Vol 35 (4) ◽  
pp. 465-474 ◽  
Author(s):  
L. Liu ◽  
H. Jiang ◽  
Y. Dong ◽  
L. Quan ◽  
Y. Tong
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Cantilever Beam ◽  
Beam Model ◽  
The Finite Element Method ◽  
Simply Supported Beam ◽  
Bending Deformation ◽  
Vascular Stents ◽  
Simply Supported ◽  
Loading Method

ABSTRACTFlexibility is a particularly important biomechanical property for intracranial vascular stents. To study the flexibility of stent, the following work was carried out by using the finite element method: Four mechanical models were adopted to simulate the bending deformation of stents, and comparative studies were conducted about the distinction between cantilever beam and simply supported beam, as well as the distinction between moment-loading method and displacement-loading method. A complete process as implanting a stent including compressing, expanding and bending was also simulated, for analyzing the effects of compressing and expanding deformation on stent flexibility. At the same time, the effects of the arrangement and the number of bridges on stent flexibility were researched. The results show that: 1. A same flexibility index was obtained from cantilever beam model and simply supported beam model; displacement-loading method is better than moment-loading for simulating the bending deformation of stents. 2. The flexibility of stent with compressing and expanding deformation is lower than that in the initial form. 3. Crossly arranging the neighboring bridges in axial direction, can effectively improve the stent flexibility and reduce the flexibility difference in various bending directions; the bridge number, has proportional non-linear correlation with the stent rigidity as well as the maximum moment required for bending the stent.

Seal Analysis and Optimization of Large Diameter Gate Valve Based on ANSYS

2013 ◽  
Vol 415 ◽  
pp. 498-501 ◽  
Author(s):  
Shu Xun Li ◽  
Lian Cui Li ◽  
Ying Zhe Hou
Keyword(s):  
Numerical Simulation ◽  
Finite Element Method ◽  
Finite Element ◽  
Theoretical Calculation ◽  
Circular Plate ◽  
Theoretical Basis ◽  
Gate Valve ◽  
Large Diameter ◽  
The Finite Element Method ◽  
Simply Supported

Aiming at the leakage problem on the top of gate valve, the finite element method is used to analyze the gate valves seal face and body, as well as the distributing laws of the stress, deformation and seal pressure are obtained. The shutter is simplified as the circular plate simply supported on the whole circle, and the gate valve is optimized according to the relevant formula to meet sealing requirement. The results show that: the combination of the numerical simulation and theoretical calculation, not only the more accurate theoretical basis for the optimization of the large diameter gate valve can be provided, but also the time of the development and design can be shorten greatly.

Study on the Static Performance of Sand Washing Tower Based on ANSYS

2014 ◽  
Vol 578-579 ◽  
pp. 917-920
Author(s):  
Jiang Hua Lv ◽  
Jia Peng Shi ◽  
Wei Hua Zhu ◽  
Feng Zhu ◽  
Chang Yan
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Stress Distribution ◽  
Finite Element Model ◽  
Element Model ◽  
Static Stability ◽  
Calculation Model ◽  
The Finite Element Method ◽  
Static Performance ◽  
The Finite Element Model

In this paper, using the finite element method,check for the Ken Swart project sand flushing water all operating tower in static stability. First of all, select unit and a calculation model, establish the finite element model; Then analys the displacement distribution and stress distribution of the structure in the five conditions.

scholarly journals Reluctance Network Model of a Permanent Magnet Tubular Motor

2017 ◽  
Vol 11 (3) ◽  
pp. 194-198 ◽  
Author(s):  
Andrzej Waindok ◽  
Bronisław Tomczuk
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Permanent Magnet ◽  
Network Model ◽  
Magnetic Circuit ◽  
Calculation Model ◽  
Air Gap ◽  
The Finite Element Method ◽  
Reluctance Network ◽  
Analytical Expressions

Abstract The reluctance network model of a permanent magnet tubular motor (PMTM) has been presented in the paper. The reluctance values of the magnetic circuit have been calculated with using analytical expressions. The air gap reluctance has been determined with using both analytical expressions and the finite element method (FEM). Using the calculation model, the flux values coupled with the windings have been obtained and used in the calculations of force value. The calculated results have been compared with numerical and measured ones.

Jacking Technology for a Simply Supported Girder Bridge

2013 ◽  
Vol 477-478 ◽  
pp. 675-680
Author(s):  
Li Ge Xu ◽  
Yi Li Wang ◽  
Chang Jie Xu
Keyword(s):  
Finite Element ◽  
Reference Value ◽  
The Finite Element Method ◽  
Stress Monitoring ◽  
Element Analysis ◽  
Simply Supported ◽  
Allowable Error ◽  
Girder Bridge ◽  
Jack Up ◽  
Engineering Projects

Numerous bridges have to be lifted to meet increased navigation capacity. However, no relevant technical standard for the jack-up technique is yet available. This paper presents a study on the integral lifting of simply supported girder bridge which implements the finite element method. Finite element analysis provides a reliable basis in controlling construction. Research shows that stress concentration is evident near support points in the lifting process. Thus, stress monitoring is necessary. These points should be near to the bridge web. Moreover, beam span and section rigidity should also be considered when jacking up a bridge. The value of allowable error in the jacking-up process decreases with increasing beam span or decreasing section stiffness. Therefore, jacking up a bridge will be safer when section rigidity is large enough and beam span is not extremely long. This paper offers tremendous reference value with regard to engineering projects.

scholarly journals Modeling of a piled foundation in a Femap with NX Nastran

2020 ◽  
Vol 16 (4) ◽  
pp. 250-260
Author(s):  
Elvira R. Kuzhakhmetova
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Pile Foundation ◽  
Strain State ◽  
Calculation Model ◽  
The Finite Element Method ◽  
Stress Strain ◽  
Foundation Soil ◽  
Stress Strain State ◽  
Building Foundation

Relevance. The underground part of the building (foundation and soil) has a significant impact on its stress-strain state and behavior under the influence of operational loads. Therefore, the existing regulatory and technical documentation regulates the design of buildings (structures), taking into account the joint work of their aboveground and underground parts. In practice, such accounting becomes possible on the basis of a comprehensive engineering analysis of the building as a large mechanical system building - foundation - soil, which today can be carried out using the finite element method. In the case of pile foundations, the correctness of the result depends largely on the reasonable choice of the design model of the pile-soil subsystem. The article analyzes three design models of piles operating in an array of soil foundation. The first model is discrete. In it, the pile is modeled by bars and is based on elastic supports (Spring) with generalized stiffnesses. Second model - spatial, in which the pile and soil are typed in by volumetric elements (Solid). Third model - spatial-bar or combined, in which the bar pile is embedded in the mesh of the soil mass using a rigid substructure formed by bars of high rigidity. The aim of the work - to determine a rational calculation model of the pile - soil subsystem, which allows, on the one hand, to reduce the general order of the system of resolving equations, and, on the other hand, to maintain the accuracy of the assessment of the stress-strain state of the calculation model of pile - soil and the building as a whole. Materials and methods. The numerical results of the analysis of the pile foundation statics using the three pile - soil calculation models were performed in the CAE software package - the Femap with NX Nastran class, which implements the finite element method. Results. Comparative-numerical analysis of the stress-strain state of the pile foundation - soil subsystem made it possible to determine the advantages, disadvantages, and also the areas of rational use of bar, spatial combined calculation models. In the next articles, it is planned to consider the calculation of piles for vertical loads, as well as a comparative analysis of numerical results with experimental data (in the labo-ratory or in field conditions) for horizontal and vertical effects.

Active Vibration Quenching Using Inverse Dynamics

1995 ◽  
Author(s):  
Thomas A. Trautt ◽  
Eduardo Bayo
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Frequency Domain ◽  
Inverse Dynamics ◽  
Equations Of Motion ◽  
Input Function ◽  
Degree Of Freedom ◽  
The Finite Element Method ◽  
Simply Supported ◽  
Active Vibration

Abstract An inverse dynamics algorithm is derived for active vibration quenching of structures. The algorithm uses frequency domain technicques to compute an input function needed to produce a desired response at a particular degree of freedom. The desired response is a transition from the initial vibrating condition to a non-vibrating condition. The algorithm can also be used to modify the input function to correct for system disturbances while the input function is already being applied to the system. The algorithm is demostrated in a simulation of a simply supported beam controlled by a torque actuator at one end of the beam. The finite element method is used to discretize the equations of motion of the beam.

scholarly journals Analysis of the braking longitudinal force considered by NBR7187 (2003) through a case study

2014 ◽  
Vol 7 (5) ◽  
pp. 801-816
Author(s):  
G. C. Bettazzi ◽  
T. B. Dumêt
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Mechanical Behavior ◽  
Cross Section ◽  
Longitudinal Force ◽  
Railway Bridge ◽  
The Finite Element Method ◽  
Fem Method ◽  
Real Behavior

This paper analyzed the mechanical behavior of a railway bridge by the Finite Element Method and by monitoring strain deformations with extensometry during its operation. To represent the situations that occur in its operation, tests were made with train braking. The results of monitoring the bottom cross section of column P15 of the bridge are presented. Based on the obtained data, the deformations occurring during the tests are verified against the calculated values obtained by the FEM method and those prescribed by NBR 7187(2003). The comparison between the real behavior of the structure, recorded experimentally through extensometry, and the numerical forecast and its assumptions from the project conceived was done. From this comparison, it verified that the value of longitudinal force due to braking recommended by the standard is appropriate.

scholarly journals Analysis of vibration of beams with regularly located openings

2021 ◽  
pp. 22-28
Author(s):  
А.И. Притыкин
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Comparative Analysis ◽  
Natural Frequencies ◽  
The Finite Element Method ◽  
Program Complex ◽  
Simply Supported ◽  
Analytical Relations ◽  
Element Method

В справочной литературе содержатся расчетные зависимости для частот свободных колебаний балок со сплошной стенкой, но отсутствуют данные по собственным колебаниям перфорированных балок. В то же время в судостроении и строительной практике широко распространены балки с перфорированной стенкой, содержащей вырезы круглой, овальной и прямоугольной формы. В статье проведен анализ влияния вырезов на частоту свободных колебаний перфорированных свободно опертых балок. При этом первоначально рассматривались балки со сплошной стенкой, а затем балки таких же размеров с вырезами. Для удобства практических вычислений известная зависимость была трансформирована к виду, позволяющему оценить частоту колебаний только по соотношению площадей полки и стенки и габаритным размерам балки без необходимости определения ее момента инерции и погонной массы. Аналогичные зависимости были получены и для перфорированных балок с круглыми и прямоугольными вырезами, в которых дополнительными факторами являлись параметры перфорации: относительная высота вырезов и относительная ширина перемычек. При отсутствии вырезов формулы для перфорированных балоксводятся к формуле для балки со сплошной стенкой.Сравнительный анализ частот проводился путем расчета по аналитическим зависимостям и методом конечных элементов с использованием программного комплекса ANSYS. На основе проведенного анализа сделан вывод, что наличие регулярно расположенных вырезов с высотой, не превышающей рекомендации Морского Регистра РФ, в зависимости от параметров перфорации приводит к разному повышению частот собственных колебаний однопролетных балок, хотя степень их повышения невелика. Предложенные аналитические зависимости для балок разного конструктивного оформления удовлетворительно согласуются с результатами расчетов МКЭ. In manual on the ship structural mechanics the analytical relations for determination of the natural frequencies of the beams with solid web are given, but there are no data about proper vibration of perforated beams. At the same time in shipbuilding and in structural industry the perforated beams with circular, rectangular and oval openings are widely used. In this article the analysis of influence of openings on the natural frequencies of the simply supported perforated beams is performed. Initially it was considered beams with solid web and then beams of the same dimensions with openings. For commodity of practical calculations, the well-known relation was transformed to the form allowing to appreciate frequency of vibration only with knowledge of ratio of areas of shelves and web without necessity of finding their moment of inertia and running mass of beam. Similar relations were obtained for perforated beams with circular and rectangular openings, in which additional arguments were such parameters of perforation as related depth of openings and related width of web-posts. In case of absence of openings, the formulas for perforated beams are reduced to formula for beam with solid web. Comparative analysis was performed by calculations according to analytical relations and with the finite element method using the program complex ANSYS. On base of performed analysis it was made conclusion that existence of regularly located openings with depth not extending recommendations of Russian Maritime Register, in dependence on parameters of perforation brings to different increasing of natural frequencies of vibration of one span beams, although degree of this increasing is not high. Suggested analytical relations for beams of different constructive design are in a good correlation with results obtained by the finite element method.

Sign in / Sign up

Export Citation Format

Share Document