scholarly journals Numerical Simulation of Some Steel Structural Elements with Uncertain Initial Porosity

Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 689
Author(s):  
Marcin Kamiński ◽  
Michał Strąkowski
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Probabilistic Method ◽  
Bending Test ◽  
Plastic Behavior ◽  
Structural Elements ◽  
Engineering Structures ◽  
Porous Plasticity ◽  
Reliability Method ◽  
Element Method

The main research purpose of this work was to study the elasto-plastic responses of some fundamental steel structural elements exhibiting stochastic volumetric microvoids. The constitutive model of the steel material was consistent with the deterministic Gurson–Tvergaard–Needleman (GTN) porous plasticity model, where some of the microvoids parameters have additionally been defined as Gaussian random variables. The iterative stochastic finite element method implemented based on the-tenth order stochastic perturbation technique was utilized in numerical experiments. An interoperability of the computer algebra system MAPLE 2019 and the finite element method system ABAQUS was employed to study the influence of the initial microvoids f0 with uncertainty in the structural steel on the statistical scattering of the resulting stresses and deformations. The basic probabilistic characteristics of the structural response were computed and contrasted with statistical estimators inherent in the Monte–Carlo simulation and also with the results obtained from the semi-analytical probabilistic method. Reliability indices according to the first-order reliability method (FORM) were also calculated. Two numerical illustrations included the (i) tension test of the round cylindrical steel rebar and the (ii) bending test of the steel I-beam restrained at both its ends. Expectations and coefficients of variation of the structural responses confirmed here the importance of the microvoids for the stochastic elasto-plastic behavior of some basic engineering structures, where tensile stress plays an important role in designing procedures.

scholarly journals Reliability Modeling in Some Elastic Stability Problems Via the Generalized Stochastic Finite Element Method / Modelowanie Niezawodnosci W Pewnych Zagadnieniach Statecznosci Sprezystej Z Wykorzystaniem Uogólnionej Stochastycznej Metody Elementów Skonczonych

2011 ◽  
Vol 57 (3) ◽  
pp. 275-295 ◽  
Author(s):  
M. Kaminski ◽  
P. Swita
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Civil Engineering ◽  
Elastic Stability ◽  
Stochastic Finite Element Method ◽  
Stochastic Finite Element ◽  
Engineering Structures ◽  
Reliability Method ◽  
Civil Engineering Structures ◽  
Element Method

Abstract The main idea of this work is to demonstrate an application of the generalized perturbation-based Stochastic Finite Element Method for a determination of the reliability indicators concerning elastic stability for a certain spectrum of the civil engineering structures. The reliability indicator is provided after the Eurocode according to the First Order Reliability Method, and computed using the higher order Taylor expansions with random coefficients. Computational implementation provided by the hybrid usage of the FEM system ROBOT and the computer algebra system MAPLE enables for reliability analysis of the critical forces in the most popular civil engineering structures like simple Euler beam, 2 and 3D single and multi-span steel frames, as well as polyethylene underground cylindrical shell. A contrast of the perturbation-based numerical approach with the Monte-Carlo simulation technique for the entire variability of the input random dispersion included into the Euler problem demonstrates the probabilistic efficiency of the perturbation method proposed.

Structural Strength Analysis and Measurement of Composite Laminate Using Finite Element Method and FBG Sensor

2016 ◽  
Vol 851 ◽  
pp. 720-727
Author(s):  
Yu Chuan Lin ◽  
Wen Jeng Hsueh
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Cantilever Beam ◽  
Composite Laminate ◽  
Structural Strength ◽  
Measuring System ◽  
Bending Test ◽  
Strength Analysis ◽  
Fbg Sensor ◽  
Element Method

The aim of this study is to develop structural strength analysis technique and real-time measuring system of composite laminate using finite element method (FEM) and fiber bragg grating (FBG) sensor. A composite laminate of cantilever beam was designed and fabricated using glass fiber reinforced plastic (GFRP) for structural mechanics behavior research. Six design cases of different orientations composite laminate were considered for the better combinations by using FEM program. The bending test of a composite laminate of cantilever beam was performed by using FBG sensor to obtained relationship between strain and displacement. The study result shows that the higher stiffness of composite laminate of cantilever beam was obtained in the [0/90/0/90] orientation. The first natural frequency is 34.83 Hz and corresponding mode shape is bending mode in Z-direction. The FEM and FBG sensor have been successfully used in variety of composite laminate design with different layering sequences by this article.

Seismic Analysis of Soil Nailed Wall Using Finite Element Method

2012 ◽  
Vol 535-537 ◽  
pp. 2027-2031 ◽  
Author(s):  
Jian Chun Wu ◽  
Rong Shi
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Seismic Analysis ◽  
Retaining Wall ◽  
Plastic Behavior ◽  
Soil Nailing ◽  
Nonlinear Fem ◽  
Elastic Plastic ◽  
Flexible Retaining Wall ◽  
Element Method

Using dynamic elastic-plastic finite element method, on the base of works together and interaction between loess and flexible retaining wall, 3-D nonlinear FEM (ADINA) is used to analyze and discussed the dynamic response of slope protected by soil nailing retaining wall under the EL-Centro and man-made Lanzhou accelerogram. A model that is capable of simulating the nonlinear static and dynamic elastic-plastic behavior of soil is used to model the soil, and a bilinear elastic-plastic model that has hardening behavior is used to model the soil nailing. Friction-element is employed to describe the soil-structure interaction behavior.The results show that the method is safe and credible. The results of the FEM dynamic analysis can be a useful reference for engineers of the design and construction of the soil nailed wall.

scholarly journals NUMERICAL ANALYSIS OF STRUCTURAL ELEMENTS BETWEEN 3D CAD SOLIDWORKS AND CODE_ASTER

2020 ◽  
Vol 7 (10) ◽  
pp. 458-470
Author(s):  
Benício de Morais Lacerda ◽  
Alex Gomes Pereira
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Complex Problem ◽  
Numerical Results ◽  
Good Precision ◽  
Institutional Research ◽  
Structural Elements ◽  
The Finite Element Method ◽  
Numerical Application ◽  
Element Method

This study aimed to investigate numerically the validation of the use of the free license program Code_ Aster, with numerical results of the SolidWorks program. For this, four metal elements were modeled, all of them subjected to the tensile stress, they are: a cylindrical bar, two plates with a hole and a metal console. The objective is to validate the use of a free program for analysis of structural elements in engineering office projects and institutional research to verify if the results obtained from the free program show significant differences in the numerical application of a commercial program. All programs have in their design of analysis the use of the finite element method (FEM). The finite element method (FEM) consists to divide a continuous object into a finite number of parts. This allows a complex problem to be transformed into a set of simple problems (finite element) in addition to solving a set of finite elements by approximations with good precision of the results and to model the problem in a real physical way. It was observed that the numerical results between the SolidWorks program and the free program Code_ Aster were close with differences of less than 5%, which indicates the reliability of the use of Code_ Aster for numerical analyzes of structural elements of engineering projects and also in institutional research.

Deformation Behavior of Bellows Pipes for Laying Cables Under Ground by Axial Load and Bending Moment

2005 ◽  
Author(s):  
Satoshi Tehara ◽  
Hisashi Naoi ◽  
Hideki Okada ◽  
Makoto Osaku
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Numerical Analysis ◽  
Deformation Behavior ◽  
Axial Load ◽  
Bending Moment ◽  
Bending Test ◽  
Ground Subsidence ◽  
Buried Pipe ◽  
Element Method

Recently, electricity demand is rising steeply with advance of science. Additionally quantity of cables such as telephone and optical fiber is rising with communications development and increase of residence. These cables are untidily wired in the air with telephone pole. They impair cityscape and disturb pedestrian safety. Therefore improvement of procedures installing cables is requested. In order to solve it, the plan [1] which buries cables protected in pipes under ground is progressing. They are called buried pipes and consist of straight pipe made from stainless steel or plastic. However there is concern that the buried pipe is crushed and broken by the complex load due to earthquake and ground subsidence. Thus, it is necessary to develop the buried pipe with function of flexibly against damage or rupture. We focus attention to U-type bellows pipe with function of flexibly. In this study, we conduct tensile, compressive, bending test and numerical analysis of those tests using finite element method. From result, we investigate for the relationship between mechanical characteristic and deformation behavior. We study application of bellows pipe to buried pipe. In this study, we examined and analyzed deformation behavior when axial load and bending moment were given to specimens. Examinations items are as (1) we measured load, elongation bending radius by using are experimental device which modeled ground subsidence. (2) We obtained deformation behavior by numerical analysis by using constituted equations of solid mechanics. (3) We conducted simulation analysis of models constructed by finite element method. By comparing these three items, the deformation behavior is clarified.

Probabilistic Fracture Mechanics Using Fractal Finite Element Method

2008 ◽  
Author(s):  
R. M. Reddy ◽  
B. N. Rao
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Fracture Mechanics ◽  
Mixed Mode ◽  
Fracture Parameter ◽  
Shape Sensitivity ◽  
Probabilistic Fracture Mechanics ◽  
Reliability Method ◽  
Cracked Structures ◽  
Element Method

This paper presents probabilistic fracture-mechanics analysis of linear-elastic cracked structures subjected to mixed-mode (modes I and II) loading conditions using fractal finite element method (FFEM). The method involves FFEM for calculating fracture response characteristics; statistical models of uncertainties in load, material properties, and crack geometry; and the first-order reliability method for predicting probabilistic fracture response and reliability of cracked structures. The sensitivity of fracture parameters with respect to crack size, required for probabilistic analysis, is calculated using continuum shape sensitivity analysis. Numerical examples based on mode-I and mixed-mode problems are presented to illustrate the proposed method. The results show that the predicted failure probability based on the proposed formulation of the sensitivity of fracture parameter is accurate in comparison with the Monte Carlo simulation results. Since all gradients are calculated analytically, reliability analysis of cracks can be performed efficiently using FFEM.

Analysis of forced vibrations of frameworks by finite element method using dynamic finite element.

2015 ◽  
Vol 2015 (2) ◽  
pp. 93-103 ◽  
Author(s):  
Екатерина Цуканова ◽  
Ekaterina Tsukanova
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Dynamic Stress ◽  
Forced Vibrations ◽  
Structural Elements ◽  
Dynamic Finite Element ◽  
Base Functions ◽  
Deformed State ◽  
Element Method

The analysis of forced vibrations of frameworks using finite element method is considered. The dynamic finite element, the base functions of which represent exact dynamic shapes of structural elements, is used for system discretization. The assessment of errors as a result of classic FEM application is given. The efficiency of application of dynamic finite element for analysis of forced vibrations and dynamic stress-deformed state of structures is shown.

Damage Mechanics-Finite Element Method for Vibrational Fatigue Life Prediction of Engineering Structures with Damping

2014 ◽  
Vol 472 ◽  
pp. 17-21 ◽  
Author(s):  
Lin Lin Sun ◽  
Wei Ping Hu ◽  
Miao Zhang ◽  
Qing Chun Meng
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Fatigue Life ◽  
Life Prediction ◽  
Damage Mechanics ◽  
Fatigue Crack Initiation ◽  
Engineering Structures ◽  
Engineering Structure ◽  
Crack Initiation Life ◽  
Element Method

This paper provides a new method which is damage mechanics to predict the fatigue life of engineering structure with damping under resonant loading. The material parameters are obtained by the results of the fatigue test of standard specimens. And based on the further development of APDL language, damage mechanics-finite element method for vibration life prediction under resonant loading is used in ANSYS. Finally, the vibrational fatigue crack initiation life of an aluminum alloy beam with damping carrying load of various frequencies is calculated. Whats more, this research provides a feasible way to predict the fatigue live of an engineering structure by means of damage mechanics.

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