Dissertations / Theses on the topic 'Linearly Elastic Analysis'
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1
Lee, J. Xiang (James Xiang) Carleton University Dissertation Engineering Mechanical. "Vibration analysis of linearly elastic non-conservative systems using integral equations." Ottawa, 1991.
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2
Phạm, Phú Tinh [Verfasser]. "Upper bound limit and shakedown analysis of elastic-plastic bounded linearly kinematic hardening structures / Phu Tinh Pham." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2011. http://d-nb.info/1018189491/34.
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Unal, Orhan. "3-d Soil Structure Interaction Analyses Of Three Identical Buildings In Sakarya City After 17 August 1999 Kocaeli Earthquake." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1053362/index.pdf.
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ABSTRACT
3-D SOIL STRUCTURE INTERACTION ANALYSES OF THREE
IDENTICAL BUILDINGS IN SAKARYA CITY AFTER 17 AUGUST 1999
KOCAELI EARTHQUAKE
Ünal,Orhan M.S., Department of Civil Engineering, Supervisor: Assist. Prof. Dr Kemal Ö
nder Ç
etin October 2003, 116 Pages The aim of this study is to analyze the soil structure interaction of three identical buildings on ª
ahinler Street of Sakarya city which had no damage to heavy damage after the Kocaeli (1999) earthquake. For the purpose of 3-D dynamic nonlinear analysis of the soil site and the overlying structures, Flac3D software was chosen as the numerical modeling framework. Soil properties were determined by using the results of available site investigation studies. A three dimensional mesh was created to represent the topographic and geometric constraints of the problem. Linearly elastic perfectly plastic constitutive model was implemented to model the soil behavior. The results of 3-D dynamic numerical analyses in the forms of acceleration, displacement, strain, stress and pore pressure were presented. The higher acceleration, strain and stress levels calculated under the collapsed building can be attributed as the major cause of poor performance of the structure.
4
AZEGAMI, Hideyuki, and Zhi Chang WU. "Domain Optimization Analysis in Linear Elastic Problems (Approach Using Traction Method)." 日本機械学会, 1996. http://hdl.handle.net/2237/12156.
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SEREBRENICK, GUSTAVO. "STABILITY ANALYSIS OF SLENDER COLUMNS PARTIALLY BURIED IN A NON-LINEAR ELASTIC FOUNDATION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6168@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORO presente trabalho tem por objetivo estudar o comportamento de colunas esbeltas parcialmente enterradas, quando submetidas a um carregamento axial de compressão. A fundação é representada, ora por um modelo linear, o qual considera que a reação exercida pelo solo é proporcional às deflexões da coluna, ora por um modelo não-linear no qual esta relação de proporcionalidade não é mais verificada. Para a modelagem da coluna, é usada a teoria inextensional de barras esbeltas. Inicialmente, mostra-se como são deduzidas as equações diferenciais do problema a partir dos funcionais de energia da coluna. No problema linear, buscam-se obter as cargas críticas e modos críticos da coluna. Neste caso, sua solução analítica é encontrada a partir da resolução do problema de valor de contorno usando-se um programa de álgebra simbólica. Também é obtida uma solução aproximada através do método de Ritz. Um estudo paramétrico detalhado analisa a influência das condições de apoio da coluna e altura e rigidez da fundação na carga e modo críticos. Entretanto, no caso nãolinear, as equações diferenciais são mais complexas, não permitindo a obtenção de uma solução analítica. É utilizado, então, o método de Ritz, no qual as soluções analíticas obtidas para o problema linear (autofunções) são usadas como funções de interpolação. Em seguida, chega-se à uma equação não- linear de equilíbrio, da qual se obtém o caminho pós-crítico da coluna. Os resultados do problema nãolinear são comparados com os obtidos através do método dos elementos finitos.
In this thesis the behavior of slender, partially embedded columns under axial compressive forces is studied. The foundation is either represented by a linear model, which considers that the soil reaction is proportional to the column’s deflections or by a non-linear model in which this proportionality relation is not observed. The inextensional slender beam theory is used to model the column. Initially, the governing differential equations are deduced from the energy functional of the column-foundation system. In the linear problem, the critical loads and corresponding critical modes are looked for. In this case, an analytic solution is obtained by the solution of the associated boundary value problem, using a symbolic algebra software. An approximate solution is also found by Ritz’s method. A parametric study is conducted to study the influence of the column boundary conditions and foundation’s height and stiffness on critical loads and modes. However, in the non-linear case, differential equations are much more complex and an analytical solution is not possible. So, the Ritz’s method is used once again, in which the analytic solutions of the linear problem (eigenfunctions) are used as interpolation functions. After that, a non-linear equilibrium equation is obtained together with the column post-buckling path. These results are compared with the ones obtained using the finite element method.
6
Esmen, Ekrem Alp 1977. "Three-dimensional mixed mode linear elastic fracture mechanics analysis using domain interaction integrals." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28377.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references (p. 109-111).
Three-dimensional mixed-mode linear elastic fracture mechanics analysis is presented using domain interaction integrals. An out-of-plane sinusoidal crack was analyzed using a commercially available finite element package to extract the stress intensity factors and the J-Integral. The results were then compared with those obtained from crack face relative displacements as a post-processing step. The model has been tested on various geometries and the performance of focused and non-focused meshing algorithms are compared. The behavior of the stress intensity factors under far-field K-load for growing surface roughness in the form of a sinusoidal crack have been modelled as a cosine series.
by Ekrem Alp Esmen.
S.M.
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Kendrick, John Thomas. "Design of High-Performance, Dual-Motor Liquid-Cooled, Linear Series Elastic Actuators for a Self-Balancing Exoskeleton." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83236.
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As a valuable asset in human augmentation and medical rehabilitation, exoskeletons have become a major area for research and development. They have shown themselves to be effective tools for training and rehabilitation of individuals suffering from limited mobility. However, most exoskeletons are not capable of balancing without the assistance of crutches from the user. Leveraging technology and techniques developed for force controlled humanoid robots, a project was undertaken to develop a fully self-balancing, compliant lower-body robotic exoskeleton. Due to their many beneficial features, series elastic actuators were utilized to power the joints on the exoskeleton. This thesis details the development of four linear series elastic actuators (LSEA) as part of this project. All 12-degrees of freedom will be powered by one of these four LSEA's. Actuator requirements were developed by examining human gait data and three robot-walking simulations. These four walking scenarios were synthesized into one set of power requirements for actuator development. Using these requirements, analytical models were developed to perform component trade studies and predict the performance of the actuator. These actuators utilize high-efficacy components, parallel electric motors, and liquid cooling to attain high power-to-weight ratios, while maintaining a small lightweight design. These analyses and trade studies have resulted in the design of a dual-motor liquid-cooled actuator capable of producing a peak force 8500N with a maximum travel speed of 0.267m/s, and three different single-motor actuators capable of producing forces up to 2450N continuously, with a maximum travel speeds up to 0.767m/s.Master of Science
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Schwarzer, Norbert, and Peggy Heuer-Schwarzer. "Qualitative failure analysis on laminate structures of windsurfing boards using analytical linear elastic modelling." Universitätsbibliothek Chemnitz, 2006. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200600107.
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Recently developed mathematical tools for the modelling of contact problems on thin film structures are adapted to allow the investigation of arbitrarily mixed purely isotropic and transversally isotropic laminate structures. The new tool is applied to model a variety of load problems resulting in the failure of windsurfing boards consisting of a relatively thin laminate shell and a soft polymer foam core. It is shown that local impact and distributed bending loads due to “bad landing” after high jumps or contact with parts of the sailing gear (the so called rig) especially the front part of the boom are leading to the most critical stress distributions resulting in failure. So most of the investigated boards were damaged because the rider (windsurfer) landed flat and thus produced a sudden impact force under his feet (impact defect). Other overloading occurred due to overturning of so called loop movements or the landing of the board exactly on respectively between two waves and this way producing high bending moments. Some of those typical loads are analysed in detail and the stresses occurring in the complex structure of the windsurfing boards are evaluated.
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Bellinger, Nicholas C. (Nicholas Charles) Carleton University Dissertation Engineering Mechanical. "Linear elastic fracture mechanics analysis of flat oval Bourdon tubes using finite element methods." Ottawa, 1987.
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Ozen, Onder Garip. "Comparison Of Elastic And Inelastic Behavior Of Historic Masonry Structures At The Low Load Levels." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12608248/index.pdf.
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Conventional methods used in the structural analysis are usually insufficient for the analysis of historical structures because of the complex geometry and heterogeneous material properties of the structure. Today&rsquos computing facilities and methods make FEM the most suitable analysis method for complex structural geometry and heterogeneous material properties. Even the shrinkage, creep of the material can be considered in the analysis. Because of this reason Finite Element Method (FEM) is used to analyze such structures. FEM converts the structure into finite number of elements with specific degree of freedoms and analyses the structure by using matrix algebra. However, advanced FEM methods considering the inelastic and time dependent behavior of material is a very complex and difficult task and consumes considerable time. Because of this reason, to analyze every historical structure is not feasible by applying advanced inelastic FEM, whereas elastic FEM analysis at low load levels is very helpful in understanding the behavior of the structure.The analysis of a masonry gate in the historical city, Hasankeyf is the case study of this thesis. Different common software are used in FEM to compare the stresses, deformations, modal shapes etc. of the same structure. Besides the inelastic behavior of the structure is investigated and compared with the elastic behavior of the structure. The study is intended to show that at the low load levels elastic FEM analysis is sufficient to understand the response of the structure and is preferable to the inelastic FEM analysis unless a very complex analysis is required
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del, Mar Diaz del Pino Maria, and Mesa Francisco Javier Cuadrado. "DESIGN AND ANALYSIS OF A CRYOGENIC PRESSURE VESSEL : Design and analysis of a static and standing pressure vessel, specifically for liquid methane." Thesis, Högskolan i Skövde, Institutionen för teknik och samhälle, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-5339.
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The project is a research on liquid methane. It is stored in a standing and static pressure vessel specially calculated for cryogenic purposes. All the simulations have been done using the finite element method. The finite element method (FEM) or finite element analysis (FEA) is a numerical technique to find approximate solutions for partial differential equations and it is used to simulate the strength of materials. FEM allows the user to visualize the distribution of stresses and displacements. There is a wide range of software to do FEM simulations, the software chosen for the project is Pro/Engineer Wildfire 4.0. Pro-Engineer is a CAD/CAM/CAE software developed by Parametric Technology Corporation (PTC). It provides solid modeling, assembly modeling and finite element analysis. The results obtained in the mechanical analysis executed with the application Pro-mechanica show that the designed container holds the loads applied and stands stable. The thermal analysis of the insulation verifies that the amount of heat exchanged with the environment is on acceptable levels. Finally, to protect the integrity of the structure the proper paints have been selected.
12
Pang, Zhoubao. "Modeling, Analysis, and Experimental Validation of an Electric Linear Series Elastic Actuator for an Exoskeleton." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/99159.
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Exoskeletons and humanoid robots require high-power, low-weight, and back-driveable actuators. This paper describes the design and analysis of a high-force linear series elastic actuator for a lower body exoskeleton. The actuator is powered by two motors and utilize a liquid cooling system to increase its maximum continuous torque. The actuator is capable of outputting a maximum continuous force of 4800N and a maximum speed of 0.267 m/s with a maximum continuous motor current of 18A. The Titanium leaf spring was used in the actuator to provide compliance. The spring has a median stiffness of 587 N/mm with standard deviation of 38 N/mm, validated by experiments. Dynamic model was created to analyze the normal modes and can be used for developing model-based controllers.Master of Science
Compliant Linear actuators with ball screw have become popular for humanoids robots and exoskeleton. The use of ball screw lead to high efficiency, high gear ratio and high back-drivability. The compliance or the ''softness'' of the actuator comes from Titanium leaf spring, which can storage energy during gait cycle and protect motor and the ball screw from impacts of walking. The custom liquid cooling system improves the force density for the actuator. Beam theory analysis, heat transfer analysis, and dynamics analysis were performed to provides insights for the actuator system.
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INZARULFAISHAM, Abd Rahim, and Hideyuki AZEGAMI. "Solution to Shape Optimization Problem of Linear Elastic Continuum with Prescribed Vibrational Eigen-mode." 日本機械学会, 2001. http://hdl.handle.net/2237/12180.
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Huang, Liping. "STATISTICAL METHODS IN MICROARRAY DATA ANALYSIS." UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_diss/795.
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This dissertation includes three topics. First topic: Regularized estimation in the AFT model with high dimensional covariates. Second topic: A novel application of quantile regression for identification of biomarkers exemplified by equine cartilage microarray data. Third topic: Normalization and analysis of cDNA microarray using linear contrasts.
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Blignaut, Caitlyn. "A Non-linear Visco-elastic Model for Dynamic Finite Element Simulation of Bovine Cortical Bone." Master's thesis, Faculty of Engineering and the Built Environment, 2021. http://hdl.handle.net/11427/33433.
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Modelling and simulation of the human body during an impact situation such as a car accident, can lead to better designed safety features on vehicles. In order to achieve this, investigation into the material properties and the creation of a numerical model of cortical bone is needed. One approach to creating a material model of cortical bone suitable for these situations is to describe the material model as visco-elastic, as reported by Shim et al. [1], Bekker et al. [2] and Cloete et al. [3]. The work by Shim et al. and Bekker et al. developed three-dimensional models, but do not accurately capture the transition in behaviour in the intermediate strain rate region, while Cloete et al. developed a phenomenological model which captures the intermediate strain rate behaviour in one dimension. This work aims to verify and extend these models. The intermediate strain rate regime (1 s−1 to 100 s−1 ) is of particular interest because it is a key characteristic of the behaviour of cortical bone and several studies have been conducted to gather experimental data in this region [3, 4, 5, 6]. The behaviour can be captured using non-linear viscoelastic models. This dissertation focuses on the development and implementation of a material model of cortical bone based on non-linear visco-elastic models to capture the intermediate strain rate regime behaviour. The material model was developed using uni-axial test results from cortical bone. The model by Cloete et al. has been improved and extended, and issues of local and global strain rate with regards to the viscosity have been clarified. A hereditary integral approach was taken in the analysis and implementation of discrete models and was found to be consistent with mathematical models. The model developed was extended to three dimensions in a manner similar to that of Shim et al. and Bekker et al. for implementation in commercial finite element software (LS-Dyna and Abaqus).
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Torlak, Muris. "A finite volume method for coupled numerical analysis of incompressible fluid flow and linear deformation of elastic structures /." Hamburg : Techn. Univ., Arbeitsbereiche Schiffbau, 2006. http://www.gbv.de/dms/ilmenau/toc/527629162.PDF.
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RODRIGUEZ, JORGE GUILLERMO DIAZ. "LINEAR ELASTIC FRACTURE MECHANICS ANALYSIS OF FATIGUE CRACK GROWTH UNDER COMPLEX LOADING USING THE DIGITAL IMAGE CORRELATION TECHNIQUE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36283@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
A avaliação da propagação de trincas de fadiga inclui a identificação da direção da trinca, o conhecimento do Fator de Intensidade de Tensões (SIF) equivalente, a determinação de uma taxa de crescimento de comprimento de trinca por número de ciclos da/dN e o estabelecimento de uma regra de propagação de trinca conectando SIF e da/dN, como uma regra de tipo Paris. Quando ocorrem cargas mistas e não proporcionais, esses parâmetros ainda não são totalmente compreendidos. Esta tese trata de algumas das variáveis que influenciam a propagação de trincas sob carregamento no modo misto não proporcional. A técnica de Correlação de Imagens Digitais (DIC) foi utilizada para a aquisição de imagens de corpos de prova submetidos a carregamento proporcional e não proporcional cíclico. Dois tipos de corpos de prova foram utilizados. Primeiramente, dois corpos de prova planos foram testados; um disk compact tension (DCT, em inglês) e um compact tension modificado (C (T) em inglês). Eles foram submetidos a carregamento cíclico induzindo o modo I de abertura de trinca ou modos I e II de abertura de trinca proporcionais. Em segundo lugar, os dados DIC adquiridos anteriormente, e em outro lugar, para cinco tubos finos sujeitos a carregamento cíclico foram analisados. Os tubos finos tiveram entalhes usinados a partir dos quais as trincas por fadiga iniciaram e se propagaram. Esses cinco tubos finos foram submetidos a diferentes casos de carga proporcional e não proporcional. Um corpo de prova tipo tubo fino foi exposto a carga axial e apresentou modo de abertura de trinca tipo I. Os outros quatro foram submetidos a carregamento de torção ou carga axial-torcional mista e exibiram todos os três modos de abertura de trinca I, II e III. Os campos de deslocamento adquiridos experimentalmente com a técnica DIC foram processados para calcular independentemente o SIF para cada modo de abertura existente usando formulações de mecânica de fratura elástica linear (MFLE). Uma formulação delas utilizou dados de deslocamento de campo completos adquiridos em pequenas áreas que circundavam a ponta da trinca. Outra formulação usou dados adquiridos de um par de pontos localizados ao longo dos flancos opostos das faces da trinca. Os SIFs determinados foram usados para encontrar os SIFs equivalentes e faixas de SIF equivalentes usando o critério da tensão máxima de tração (para ambas as versões 2D e 3D de combinações dos modos I-II e modos I-II-III respectivamente) que implicitamente incluíram o ângulo de propagação de trinca. Verificou-se que a inclusão do SIF no modo III experimentalmente determinado efetivamente faz diferença nas faixas do SIF e dos SIF equivalentes estimados. A curva da/dN versus faixa do SIF equivalente foi elaborado com as taxas de crescimento de trinca medidas experimentalmente e as faixas de SIF que foram encontradas usando a suposição amplamente aceita de que as trincas cresceram na direção que maximiza a tensão de tração. Para isso, extensões do modelo de Schollmann et. al. e bem como o modelo de Erdogan-Sih, que são geralmente aplicados ao carregamento proporcional, foram usados para determinar os SIFs equivalentes e faixas de SIF equivalentes para os casos de carregamento proporcional e não proporcional. Finalmente, a segunda zona da regra de Paris (da/dN versus faixa do SIF equivalente) foi plotada para os cinco casos de carregamento nos tubos finos mostrando que eles caíram dentro de uma faixa razoavelmente fina e dispersa.
Fatigue crack propagation assessment includes identifying the crack direction, knowing the equivalent Stress Intensity Factor (SIF) range, determining a crack length growth rate per number of cycles (da/dN), and establishing a crack propagation rule connecting the equivalent SIF and da/dN rate, such as a Paris type of rule. When mixed and non-proportional loading occur, those parameters are not fully understood yet. This thesis deals with some of the variables that influence crack propagation under non-proportional mixed mode loading. The Digital Image Correlation (DIC) technique was used to acquire images of test specimens subjected to cyclic proportional and non-proportional loading. Two types of specimen samples were used. Firstly, two different plate test specimens were tested; a disk compact tension (DCT), and a modified compact tension, C(T). They were subjected cyclic loading inducing crack opening mode I or proportional crack opening modes I and II. Secondly, the previously and elsewhere acquired DIC data for five thin tubes subject to cyclic loading were analyzed. The thin tubes had pre-fabricated slit-notches from which fatigue cracks initiated and propagated. Those five thin tubes were subjected to different cases of proportional and non- proportional loading. One tube specimen was exposed to axial loading and presented mode I crack opening. The other four were subjected to torsion loading or mixed axial-torsional loading and exhibited all three I, II and III crack-opening modes. The experimentally acquired DIC displacement fields were processed to independently calculate SIF for each existing opening mode using linear elastic fracture mechanics (LEFM) formulations. One formulation used full field displacement data acquired in small areas that surrounded the crack tip. Another formulation used data acquired from a pair of points located along the opposite crack flanks. The determined SIFs were used to find equivalent SIFs and equivalent SIF ranges using the maximum tensile stress criterion (for both 2D and 3D versions of combinations of modes I-II and modes I-II-III respectively) which implicitly included the crack propagation angle. It was found that the inclusion of the experimentally determined mode III SIF indeed makes a difference in the determined equivalent SIF and equivalent SIF ranges. A da/dN versus equivalent SIF ranges plot was drafted with the experimentally measured crack growth rates and the SIF ranges that were found by using the widely accepted assumption that the cracks grew in the direction that maximizes the tensile stress. For this, extensions of the Schollmann et. al. model as well as of the Erdogan-Sih model, which are generally applied to proportional loading, were used to determine equivalent SIFs and equivalent SIF ranges for the cases of proportional and non-proportional loading. Finally, the second stage of the Paris rule (da/dN versus SIF range) was plotted for the five thin tubes loading cases showing that they fell inside a reasonably thin scattered band.
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SHIMODA, Masatoshi, Hideyuki AZEGAMI, and Toshiaki SAKURAI. "Multiobjective Shape Optimization of Linear Elastic Structures Considering Multiple Loading Conditions (Dealing with Mean Compliance Minimization problems)." 日本機械学会, 1996. http://hdl.handle.net/2237/12155.
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Le, Gros Brian Neil. "Three-dimensional, non-linear finite element analysis, and elastic modulus optimization of a geometry for a non-metallic femoral stem." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ65632.pdf.
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Pluto, Malin. "Tank Shell Design According to Eurocodes and Evaluation of Calculation Methods." Thesis, Karlstads universitet, Institutionen för ingenjörsvetenskap och fysik (from 2013), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-68668.
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Tanks are storage vessels for liquids. They can have different appearances; some are short and wide, others are tall and slim, some are small, others are large. In this thesis a tank of 6 m in both diameter and height has been used to obtain numerical results of the stresses in the tank. Tanks are most often thin-walled with stepwise variable shell thickness with thicker wall sections at the bottom of the tank and thinner at the top. Since they are thin-walled they are susceptible to buckling and there are conditions the shell construction must meet. The conditions that has to be met are determined by the laws and regulations that govern tank design. The National Board of Housing, Building and Planning (Boverket) is the new Swedish authority for rules of tank design and the Eurocodes are the new family of standards that should be followed. Sweco Industry AB is the outsourcer of this thesis and wants to clarify what rules that apply now when the Eurocodes are to be followed. The thesis project has produced a calculation document in Mathcad for tank shell design according to the Eurocodes with stress calculations according to membrane theory and linear elastic shell analysis. This thesis has also produced a comparison of stresses calculated using membrane theory, linear elastic shell analysis and finite element method (FEM). The comparison has been made for numerical results given for an arbitrarily designed tank wall. The loads acting on the tank included in the description were self-weight, internal and hydrostatic pressure as well as wind and snow loads. The loads were described in accordance with the Eurocodes. Some assumptions had to be made where the standard was vague or deficient in order to make calculations by hand possible. For example, the wind load had to be described as an axisymmetrically distributed load rather than an angularly varying. The stresses in the tank wall were calculated through creating free-body diagrams and declaring equations for force and moment equilibrium. The loads and boundary conditions were set in a corresponding manner in the FEM software Ansys as in the calculation document in order to obtain comparable results. When compared, the stress results calculated with membrane theory and FEM were quite similar while the stresses calculated with linear analysis were a lot larger. The bending moments were assumed to be too large which make the results of the linear analysis dominated by the moments. The arbitrarily dimensions set for the tank did thus not fullfill the conditions when linear analysis was used but did so for membrane theory and FE-analysis. Since the results calculated with membrane theory were very close to FEM in most cases, even without expressions for local buckling, it was assumed to be an adequate method in this application. Expressions for local buckling are although needed for the meridional normal stress. The conclusions of the results obtained are that membrane theory is a simple and adequate method in most cases. Linear analysis thus becomes redundant since it is more complicated and more easily leads to faulty results. Furthermore it cannot be used for higher consequence classes than membrane theory. FEM, with a computer software such as Ansys, is although the most usable calculation method since it can conduct more complicated calculations and is allowed to be used for all consequence classes.
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Amireghbali, Aydin. "Elastic Analysis Of A Circumferential Crack In An Isotropic Curved Beam Using Modified Mapping-collocation Method." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615675/index.pdf.
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The modified mapping-collocation (MMC) method is applied to analyze a circumferential
crack in an isotropic curved beam. Based on the method a MATLAB code was developed to
obtain the stress field. Incorporating the stress correlation technique, the opening and sliding
fracture mode stress intensity factors (SIF)s of the crack for the beam under pure bending
moment load case are calculated.
The MMC method aims to solve two-dimensional problems of linear elastic fracture mechanics
(LEFM) by combining the power of analytic tools of complex analysis (Muskhelishvili
formulation, conformal mapping, and extension arguments) with simplicity of applying the
boundary collocation method as a numerical solution approach.
Qualitatively, a good agreement between the computed stress contours and the fringe shapes
obtained from the photoelastic experiment on a plexiglass specimen is observed. Quantitatively,
the results are compared with that of ANSYS finite element analysis software. The
effect of crack size, crack position and beam thickness variation on SIF values and mode
mixity is investigated.
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David, Sergio Adriani. "Modelagem dinamica, simulação e validação experimental de estruturas flexiveis." [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265325.
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Orientador : João Mauricio RosarioTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Neste trabalho desenvolveu-se a modelagem dinâmica de estruturas flexíveis, a investigação de seu comportamento não linear por meio de simulações numéricas e a validação experimental através da montagem de um protótipo. Ressalta-se que em se tratando de sistemas não lineares, embora existam métodos de procedimento, não existe uma teoria única que possa atender às diferentes aplicações e necessidadesde análise não linear. Dessa maneira, abordou-se formas específicas de se tratar duas aplicações distintas, uma envolvendo manipuladores robóticos flexíveis e a outra um oscilador mecânico flexível. Desenvolveu-se ferramentas de modelagem, simulação, análise e implementação. A aplicação envolvendo o oscilador mecânico flexível teve âmbitos experimentais e os resultados de alguns ensaios sugerem uma boa concordância com o modelo teórico. Os resultados obtidos desse trabalho e o aparato experimental montado, ambos, permitem que diversas investigações futuras ainda possam ser realizados definidas e podem agregar conhecimento sobretudo aos interessados em temas relacionados à estruturas flexíveis e análise não linear
Abstract: This work deserihes the dynamic modeling of flexible structures. the investigation about its nonlinear behaviour through numerical simulations and the construction of an experimental appararus in order to validate the model. I outline the fact that to deal with nonlinear systems, although there are conduct method, there isn't a unique theory that could to attend to different applications and necessities of nonlinear analysis. For this reason, specific approach had been presented to deal with two applications, flexible robot manipulators and flexible mechanical oscillator. Dynamic modeling, numerical simulation, analysis and implement are performed. The application which involves the flexible mechanical oscillator have experimental scope and the results have showed a good agreement with the theoretical model. The results obtained and the experimental apparatus COnstructed. both, allow sundry future investigations and can add knowledge specially to the interested in flexible structures and nonlinear analysis
Doutorado
Mecanica dos Sólidos e Projeto Mecanico
Doutor em Engenharia Mecânica
23
Yildirim, Suat. "Comparative Study Of Commercial Structural Analysis Programs In View Of Seismic Assessment Procedures In Turkish Earthquake Code 2007." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12612864/index.pdf.
Full textAbstract:
In Turkey, most of the existing buildings have been designed according to Turkish Earthquake codes of 1975 and 1997. It is a well known fact that, poor material quality, poor design, poor control on site and inadequate workmanship makes existing buildings vulnerable to earthquake. In addition, change in function of buildings becomes another problem. These problems increase the importance of assessment of existing buildings. For this purpose, a new chapter has been added to the new code and assessment methods of existing buildings is regulated. 2007 Turkish Earthquake Code offered two analysis methods, linear and nonlinear analysis methods. Due to comprehensive computational, modeling and assessment challenges involved in applying the code procedures that are generally not well understood by practicing engineers, the use of commercial package computer programs is preferred. There are widely used three software&rsquos in Turkey
Idestatik, Sta4 and Probina. These programs currently handle linear assessment method only. This study aims to compare the assessment results of the most widely used three structural analysis and design softwares in Turkey. For this purpose, four v different structures having different property and plan were employed. These buildings were selected to be representative of the mostly common building types. Each building has been modeled and identified with the same material properties, the same reinforcement details and the same geometric properties in each software. The results of the assessment are compared in order to determine the inconsistencies among the software&rsquo
s and their reliability.
24
Ozturk, Ismail. "A Comparative Assessment Of An Existing Reinforced Concrete Building By Using Different Seismic Rehabilitation Codes And Procedures." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608036/index.pdf.
Full textAbstract:
Lateral load carrying capacities of reinforced concrete structures which are designed
by considering only gravity loads or according to outdated earthquake codes can be
insufficient. The most important problem for these buildings is the limited ductility
of the frame elements. How to evaluate the performance of an existing structure and
to what level to strengthen it had been major concerns for structural engineers.
Recent earthquakes which occurred in the Marmara Region in the last decade have
increased the number of seismic assessment projects drastically. However, there
was no special guideline or code dealing with the assessment of existing buildings.
In order to have uniformity in assessment projects, a new chapter has been included
in the revised Turkish Earthquake Code (2006).
In this study, the existing and retrofitted conditions of a reinforced concrete
building were assessed comparatively by employing linear and nonlinear
assessment procedures according to different seismic rehabilitation codes. The
study was carried out on a six storey reinforced concrete telephone exchange
building. Although there was no damage in the structure due to the recent
earthquakes that occurred in the Marmara Region, the building was assessed and
retrofitted in 2001 by using equivalent lateral load analysis results. The results of
linear and nonlinear assessment procedures performed in the scope of this thesis,
were also compared with the assessment results of this previous study.
In the nonlinear assessment procedures, pushover analysis results were used. In
addition to comparison of the assessment procedures, efficiency of a widely used
approximate pushover method was also investigated.
25
Masada, Teruhisa. "Structural performance of profile-wall plastic pipes under relatively shallow soil cover and subjected to large surface load." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1174611925.
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26
Rizik, Vivian. "Analysis of an elasto-visco-plastic model describing dislocation dynamics." Thesis, Compiègne, 2019. http://www.theses.fr/2019COMP2505.
Full textAbstract:
Dans cette thèse on s'intéresse à l'analyse théorique et numérique de la dynamique des densités des dislocations, où les dislocations sont des défauts cristallins, apparaissant à l'échelle microscopique dans les alliages métalliques. En particulier, on considère en premier temps l'étude du modèle de Groma-Czikor-Zaiser (GCZ) et en second temps l'étude du modèle de Groma-Balog (GZ). Il s'agit en réalité d'un système d'équations de type paraboliques et de type Hamilton-Jacobi non-linéaires. Au départ, nous démontrons un résultat d'existence et d'unicité d'une solution régulière en utilisant le principe de comparaison et un argument de point fixe pour concernant le modèle GCZ. Ensuite, nous démontrons un résultat d'existence global en temps pour le modèle de GB, en se basant sur les notions des solutions de viscosités discontinues et sur une nouvelle estimation sur la variation totale de la solution, ainsi que sur la propagation à vitesse finie des équations régissantes. Ce résultat est étendu aussi au cas des systèmes d'équations d'Hamilton-Jacobi général. Enfin, nous proposons un schéma numérique semi-explicite permettant la discrétisation du modèle de GB. Nous montons, en s'appuyant sur l'étude théorique, que la solution discrète convergent vers la solution continue, ainsi qu'une estimation d'erreur entre la solution continue et la solution numérique. Des simulations montrant la robustesse du schème numériques sont également présentéesIn this thesis, we are interested in the theoretical and numerical analysis o the dynamics of dislocation densities, where dislocations are crystalline defects appearing at the microscopic scale in metallic alloys. Particularly, the study of the Groma-Czikor-Zaiser model (GCZ) and the study of the Groma-Balog model (GB) are considered. The first is actually a system of parabolic type equations, where as, the second is a system of non-linear Hamilton-Jacobi equations. Initially, we demonstrate an existence and uniqueness result of a regular solution using a comparison principle and a fixed point argument for the GCZ model. Next, we establish a time-based global existence result for the GB model, based on notions of discontinuous viscosity solutions and a new estimate of total solution variation, as well as finite velocity propagation of the governed equations. This result is extended also to the cas of general Hamilton-Jacobi equation systems. Finally, we propose a semi-explicit numerical scheme allowing the discretization of the GB model. Based on the theoretical study, we prove that the discrete solution converges toward the continuous solution, as well as an estimate of error between the continuous solution and the numerical solution has been established. Simulations showing the robustness of the numerical scheme are also presented
27
Sohrabi, Maria, and Loarte José Sanchez. "Crack propagation in concrete dams driven by internal water pressure." Thesis, KTH, Betongbyggnad, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211648.
Full textAbstract:
Concrete structures are in general expected to be subjected to cracking during its service life. This is the reason why concrete is reinforced, where the reinforcement is only activated after cracks occur. However, cracks may be a concern in large concrete structures, such as dams, since it may result in reduced service life. The underlying mechanisms behind crack formations are well known at present day. On the other hand, information concerning the crack condition over time and its influence on the structure is limited, such as the influence of water pressure within the cracks. The aim of this project is to study crack propagation influenced by water pressure and to define an experimental test setup that allows for crack propagation due to this load. Numerical analyses have been performed on an initial cracked specimen to study the pressure along the crack propagation. The finite element method has been used as the numerical analysis tool, through the use of the software ABAQUS. The finite element models included in these studies are based on linear or nonlinear material behavior to analyze the behavior during a successively increasing load. The numerical results show that a crack propagates faster if the water is keeping up with the crack extension, i.e. lower water pressure is required to open up a new crack. When the water does not have time to develop within the crack propagation, more pressure is required to open up a new crack. The experimental results show that the connection between the water inlet and the specimen is heavily affected by the bonding material. In addition, concrete quality and crack geometry affects the propagation behavior.
28
Solomon, Mary Joanna. "Multivariate Analysis of Korean Pop Music Audio Features." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1617105874719868.
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Barsoum, Zuheir. "Residual Stress Analysis and Fatigue Assessment of Welded Steel Structures." Doctoral thesis, Stockholm : Farkost och flyg, Kungliga Tekniska högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4687.
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Paucar, Casas Walter Jesus. "Concepção otima de sistemas elasto-acusticos interiores acoplados." [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265126.
Full textAbstract:
Orientador: Renato PavanelloTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Neste trabalho desenvolveram-se metodologias para a obtenção de formas ótimas em sistemas vibroacústicos acoplados, via mudança de parâmetros geométricos, usando a análise de sensibilidade e ferramentas de programação não linear. As equações matriciais do problema são determinadas com o método dos elementos finitos, e expostas de forma a se tornarem dependentes dos parâmetros estruturais. Uma formulação não simétrica em deslocamento da estrutura e pressão do fluido é utilizada para descrever o sistema. Obtidas as freqüências e modos próprios para um conjunto de parâmetros, executa-se o processo de otimização usando a análise de sensibilidade modal. O objetivo é maximizar o afastamento de freqüências naturais adjacentes, ou diminuir a resposta numa região do sistema para uma faixa predefinida de freqüências de excitação, modificando para isso os parâmetros de forma. O efeito do amortecimento proporcional é incluído na modelagem. Os resultados obtidos são validados a partir de soluções numéricas disponíveis na literatura. A utilização da predição modal no processo de otimização também é analisada. A implementação da metodologia desenvolvida encontra aplicação, por exemplo, na melhora do conforto vibroacústico
Abstract: In this research some methodologies for obtaining optimal forms in coupled vibroacoustic problems are developed, through geometrical parameter changing, using sensitivity analysis and non linear programming tools. The matrix equations of the problem are determined through the finite element method, and then put in such a form that they become functions of the structural parameters. A non symmetrical formulation in structural displacement and tluid pressure is used to describe the system. Once the natural frequencies and modes for a set of parameters are found, the optimization process is conducted using the modal sensitivity analysis. The objective is either to maximize the gap between some adjacent natural frequencies,or to minimizethe frequency response in a specific region of the system for one set of excitation frequencies.This is done by modifying the shape parameters. The effect of proportional damping is included in the model. The results are validated with numerical solutions available in the literature. Additional results using the modal prediction in the optimization are also analyzed. The implemented methodology can be applied, for example, in the improvement of the vibroacoustic confort
Doutorado
Mecanica dos Sólidos e Projeto Mecanico
Doutor em Engenharia Mecânica
31
畔上, 秀幸, Hideyuki Azegami, 志強 呉, and Zhi Chang Wu. "線形弾性問題における領域最適化解析（力法によるアプローチ）." 日本機械学会, 1994. http://hdl.handle.net/2237/7239.
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32
Kurniawan, Cyrilus Winatama. "Flexural behaviour and design of the new LiteSteel beams." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16674/1/Cyrilus_Kurniawan_Thesis.pdf.
Full textAbstract:
The flexural capacity of the new hollow flange steel section known as LiteSteel beam (LSB) is limited by lateral distortional buckling for intermediate spans, which is characterised by simultaneous lateral deflection, twist and web distortion. Recent research based on finite element analysis and testing has developed design rules for the member capacity of LiteSteel beams subject to this unique lateral distortional buckling. These design rules are limited to a uniform bending moment distribution. However, uniform bending moment conditions rarely exist in practice despite being considered as the worst case due to uniform yielding across the span. Loading position or load height is also known to have significant effects on the lateral buckling strength of beams. Therefore it is important to include the effects of these loading conditions in the assessment of LSB member capacities.
Many steel design codes have adopted equivalent uniform moment distribution and load height factors for this purpose. But they were derived mostly based on data for conventional hot-rolled, doubly symmetric I-beams subject to lateral torsional buckling. In contrast LSBs are made of high strength steel and have a unique crosssection with specific residual stresses and geometrical imperfections along with a unique lateral distortional buckling mode. The moment distribution and load height effects for LSBs, and the suitability of the current steel design code methods to accommodate these effects for LSBs are not yet known. The research study presented in this thesis was therefore undertaken to investigate the effects of nonuniform moment distribution and load height on the lateral buckling strength of simply supported and cantilever LSBs.
Finite element analyses of LSBs subject to lateral buckling formed the main component of this study. As the first step the original finite element model used to develop the current LSB design rules for uniform moment was improved to eliminate some of the modelling inaccuracies. The modified finite element model was validated using the elastic buckling analysis results from well established finite strip analysis programs. It was used to review the current LSB design curve for uniform moment distribution, based on which appropriate recommendations were made.
The modified finite element model was further modified to simulate various loading and support configurations and used to investigate the effects of many commonly used moment distributions and load height for both simply supported and cantilever LSBs. The results were compared with the predictions based on the current steel code design rules. Based on these comparisons, appropriate recommendations were made on the suitability of the current steel code design methods. New design recommendations were made for LSBs subjected to non-uniform moment distributions and varying load positions. A number of LSB experiments was also undertaken to confirm the results of finite element analysis study.
In summary the research reported in this thesis has developed an improved finite element model that can be used to investigate the buckling behaviour of LSBs for the purpose of developing design rules. It has increased the understanding and knowledge of simply supported and cantilever LSBs subject to non-uniform moment distributions and load height effects. Finally it has proposed suitable design rules for LSBs in the form of equations and factors within the current steel code design provisions. All of these advances have thus further enhanced the economical and safe design of LSBs.
33
Kurniawan, Cyrilus Winatama. "Flexural behaviour and design of the new LiteSteel beams." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16674/.
Full textAbstract:
The flexural capacity of the new hollow flange steel section known as LiteSteel beam (LSB) is limited by lateral distortional buckling for intermediate spans, which is characterised by simultaneous lateral deflection, twist and web distortion. Recent research based on finite element analysis and testing has developed design rules for the member capacity of LiteSteel beams subject to this unique lateral distortional buckling. These design rules are limited to a uniform bending moment distribution. However, uniform bending moment conditions rarely exist in practice despite being considered as the worst case due to uniform yielding across the span. Loading position or load height is also known to have significant effects on the lateral buckling strength of beams. Therefore it is important to include the effects of these loading conditions in the assessment of LSB member capacities. Many steel design codes have adopted equivalent uniform moment distribution and load height factors for this purpose. But they were derived mostly based on data for conventional hot-rolled, doubly symmetric I-beams subject to lateral torsional buckling. In contrast LSBs are made of high strength steel and have a unique crosssection with specific residual stresses and geometrical imperfections along with a unique lateral distortional buckling mode. The moment distribution and load height effects for LSBs, and the suitability of the current steel design code methods to accommodate these effects for LSBs are not yet known. The research study presented in this thesis was therefore undertaken to investigate the effects of nonuniform moment distribution and load height on the lateral buckling strength of simply supported and cantilever LSBs. Finite element analyses of LSBs subject to lateral buckling formed the main component of this study. As the first step the original finite element model used to develop the current LSB design rules for uniform moment was improved to eliminate some of the modelling inaccuracies. The modified finite element model was validated using the elastic buckling analysis results from well established finite strip analysis programs. It was used to review the current LSB design curve for uniform moment distribution, based on which appropriate recommendations were made. The modified finite element model was further modified to simulate various loading and support configurations and used to investigate the effects of many commonly used moment distributions and load height for both simply supported and cantilever LSBs. The results were compared with the predictions based on the current steel code design rules. Based on these comparisons, appropriate recommendations were made on the suitability of the current steel code design methods. New design recommendations were made for LSBs subjected to non-uniform moment distributions and varying load positions. A number of LSB experiments was also undertaken to confirm the results of finite element analysis study. In summary the research reported in this thesis has developed an improved finite element model that can be used to investigate the buckling behaviour of LSBs for the purpose of developing design rules. It has increased the understanding and knowledge of simply supported and cantilever LSBs subject to non-uniform moment distributions and load height effects. Finally it has proposed suitable design rules for LSBs in the form of equations and factors within the current steel code design provisions. All of these advances have thus further enhanced the economical and safe design of LSBs.
34
Schifani, Guido. "Forme et dynamique de boîtes quantiques sous contraintes élastiques." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4069/document.
Full textAbstract:
Le but de cette thèse est l'étude théorique de la dynamique du murissement des boites quantiques auto-organisées. Pour cela, nous déduisons en utilisant les outils de la mécanique des milieux continus, une équation pour l'évolution spatio-temporelle d'un film cristallin en hétéroépitaxie en prenant en compte les effets de diffusion de surface, les effets élastiques, les effets capillaires et les effets d'anisotropie d'énergie de surface. Nous étudions tout d'abord la morphologie 2D et la dynamique de boites quantiques isotrope et anisotrope. Dans chaque cas, nous trouvons de manière quasi analytique une famille continue de solution qui décrit la forme et la taille des ilots. Ces solutions sont en accord avec nos simulations numériques. Dans les deux cas, nous trouvons que le temps de murissement dépend linéairement de la distance entre ilots et en particulier dans le cas anisotrope nous mettons en évidence le fait que le temps de murissement est soit réduit ou soit accéléré en fonction de la hauteur des pair d'ilots. Dans un second temps, motivé par des résultats expérimentaux sur les boites quantiques de GaN, nous étudions la dynamique tridimensionnelle d'ilots avec une énergie d'énergie de surface avec symétrie hexagonale. Nos simulations numériques montrent que le temps de murissement est fortement réduit dû à la présence de l'anisotropie d'énergie de surface et qu'une transition entre des ilots hexagonaux et allongés apparait en fonction de l'épaisseur du film. Finalement, nous prenons en compte dans notre modèle numérique la présence de l'évaporation préférentielle et nous mettons en évidence la présence d'ilots sans couche de mouillage. Ces ilots sont observés expérimentalement et ont une haute efficacité d'émission par photoluminescence dans le spectre UVThe aim of this thesis is to theoretically study the coarsening dynamics of self-organized quantum dots. To this end, we derive the spatio-temporal evolution equation for a hetero-epitaxial system which takes into account surface diffusion, elastic effect, capillary effect and anisotropic effect, using the continuous mechanics framework. We first investigate theoretically the 2D morphology and the dynamics of an isotropic and an anisotropic system of self-organized islands (quantum dots). In both cases, we find a quasi-analytical continuous family of solution which describes the shape and the size of the islands and is favorably compared to our numerical simulations. We find in both cases that the coarsening time depends linearly on the distance between the islands and remarkably that in the anisotropic case the coarsening time can be reduced or accelerated depending on the islands heights. Secondly, motivated by experimental results on GaN quantum dots we study a three-dimensional system with a hexagonal surface energy anisotropy symmetry. Our numerical simulations reveal that the coarsening time is strongly slowed down due to the presence of the surface energy anisotropy and that a transition from hexagonal to elongated islands appears as the initial height of the film increases. Finally, we include the effect of preferential evaporation and we recover islands without a wetting layer that are observed experimentally and have a high photo-luminescence emission efficiency in the UV spectrum
35
Walubita, Lubinda F. "Comparison of fatigue analysis approaches for predicting fatigue lives of hot-mix asphalt concrete (HMAC) mixtures." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/3898.
Full textAbstract:
Hot-mix asphalt concrete (HMAC) mixture fatigue characterization constitutes a fundamental component of HMAC pavement structural design and analysis to ensure adequate field fatigue performance. HMAC is a heterogeneous complex composite material of air, binder, and aggregate that behaves in a non-linear elasto-viscoplastic manner, exhibits anisotropic behavior, ages with time, and heals during traffic loading rest periods and changing environmental conditions. Comprehensive HMAC mixture fatigue analysis approaches that take into account this complex nature of HMAC are thus needed to ensure adequate field fatigue performance. In this study, four fatigue analysis approaches; the mechanistic empirical (ME), the calibrated mechanistic with (CMSE) and without (CM) surface energy measurements, and the proposed NCHRP 1-37A 2002 Pavement Design Guide (MEPDG) were comparatively evaluated and utilized to characterize the fatigue resistance of two Texas HMAC mixtures in the laboratory, including investigating the effects of binder oxidative aging. Although the results were comparable, the CMSE/CM approaches exhibited greater flexibility and potential to discretely account for most of the fundamental material properties (including fracture, aging, healing, visco-elasticity, and anisotropy) that affect HMAC pavement fatigue performance. Compared to the other approaches, which are mechanistic-empirically based, the CMSE/CM approaches are based on the fundamental concepts of continuum micromechanics and energy theory.
36
Tan, Mustafa Tumer. "Seismic Strengthening Of A Mid-rise Reinforced Concrete Frame Using Cfrps: An Application From Real Life." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610562/index.pdf.
Full textAbstract:
SEISMIC STRENGTHENING OF A
MID-RISE REINFORCED CONCRETE FRAME
USING CFRPs: AN APPLICATION FROM REAL LIFE
Tan, Mustafa Tümer M.S., Department Of Civil Engineering Supervisor: Prof. Dr. Gü
ney Ö
zcebe Co-Supervisor: Assoc. Prof. Dr. BariS Binici May 2009, 162 pages FRP retrofitting allows the utilization of brick infill walls as lateral load resisting elements. This practical retrofit scheme is a strong alternative to strengthen low to mid-rise deficient reinforced concrete (RC) structures in Turkey. The advantages of the FRP applications, to name a few, are the speed of construction and elimination of the need for building evacuation during construction. In this retrofit scheme, infill walls are adopted to the existing frame system by using FRP tension ties anchored the boundary frame using FRP dowels. Results of experiments have previously shown that FRP strengthened infill walls can enhance lateral load carrying capacity and reduce damage by limiting interstory drift deformations. In previous, analytical studies, a detailed mathematical model and a simplified version of the model for compression struts and tension ties was proposed and verified by comparing model estimations with test results. In this study, an existing 9-storey deficient RC building located in Antakya was chosen to design and apply a hybrid strengthening scheme with FRPs and reduced number of shear walls. Linear elastic analysis procedure was utilized (force based assessment technique) along with the rules of Mode Superposition Method for the reftrofit design. FRP retrofit scheme was employed using the simplified model and design was conducted such that life safety performance criterion is satisfied employing elastic spectrum with 10% probability of exceedance in 50 years according to the Turkish Earthquake Code 2007. Further analytical studies are performed by using Modal Pushover and Nonlinear Time-History Analyses. At the end of these nonlinear analyses, performance check is performed according to Turkish Earthquake Code 2007, using the strains resulting from the sum of yield and plastic rotations at demand in the critical sections. CFRP retrofitting works started at October 2008 and finished at December 2008 for the building mentioned in this study. Eccentric reinforced concrete shearwall installation is still being undertaken. All construction business is carried out without evacuation of the building occupants. This project is one of the first examples of its kind in Turkey. Keywords: CFRP, Carbon Fiber Reinforced Polymers, Masonry Infill Walls, Reinforced Concrete Infill Walls, Mid-Rise Deficient Structures, Turkish Earthquake Code 2007, Modal Pushover Analysis, Nonlinear Time History Analysis, Linear Elastic Building Assessment
37
Baklouti, Sana. "Vibration Analysis and Reduction of Cable-Driven Parallel Robots." Thesis, Rennes, INSA, 2018. http://www.theses.fr/2018ISAR0034/document.
Full textAbstract:
Cette thèse vise à améliorer le positionnement statique et la précision de suivi de trajectoire des Robots Parallèles à Câbles (RPC) tout en prenant en compte leur élasticité globale. A cet effet, deux stratégies de commandes complémentaires valables pour toute configuration de RPC sont proposées.Tout d'abord, une analyse de robustesse est réalisée pour aboutir à une commande robuste des RPC référencée modèle. Un modèle de RPC approprié est défini en fonction de l'application visée et les principales sources d'erreurs de pose de la plate-forme mobile sont identifiées.Une première méthode de commande est proposée sur la base des résultats de l'analyse de robustesse. Cette première méthode réside dans le couplage d'une commande référencée modèle d’un contrôleur PID.Dans le cadre de cette thèse, un modèle élasto-dynamique de RPC est exprimé afin de compenser le comportement oscillatoire de sa plate-forme mobile dû à l'élongation des câbles et de son comportement dynamique.La deuxième méthode de commande utilise des filtres "input-shaping" dans la commande référencée modèle proposée afin d'annuler les mouvements oscillatoires de la plate-forme mobile. Ainsi, le signal d'entrée est modifié pour que le RPC annule automatiquement les vibrations résiduelles. Les résultats théoriques obtenus sont validés expérimentalement à l'aide d'un prototype de RPC non redondant en actionnement et en configuration suspendue. Les résultats expérimentaux montrent la pertinence des stratégies de commande proposées en termes d'amélioration de la précision de suivi de trajectoire et de réduction des vibrationsThis thesis aims at improving the static positioning and trajectory tracking accuracy of Cable- Driven Parallel Robots (CDPRs) while considering their overall elasticity. Accordingly, two complementary control strategies that are valid for any CDPR configuration are proposed.First, a robustness analysis is performed to lead to a robust model-based control of CDPRs. As a result, an appropriate CDPR model is defined as a function of the targeted application and the main sources of CDPR moving-platforms pose errors are identified.A first control method is determined based on the results of the robustness analysis. This first method lies in the coupling of a model-based feed-forward control scheme for CDPR with a PID feedback controller.Here, an elasto-dynamic model of the CDPR is expressed to compensate the oscillatory motions of its moving-platform due to cable elongations and its dynamic behavior.The second control method uses input-shaping filters into the proposed model-based feed-forward control in order to cancel the oscillatory motions the movingplatform. Thus, the input signal is modified for the CDPR to self-cancel residual vibrations.Experimental validations are performed while using suspended and non-redundant CDPR prototype. The proposed feed-forward model-based control schemes are implemented, and their effectiveness is discussed.Results show the relevance of the proposed control strategies in terms of trajectory tracking accuracy improvement and vibration reduction
38
Morton, Ellen C. "Static testing of large scale ground support panels." Thesis, Curtin University, 2009. http://hdl.handle.net/20.500.11937/2067.
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The Western Australian School of Mines (WASM) developed a large area static test facility to enable the evaluation of three forms of surface support; namely, mesh, shotcrete and membranes. The purpose of this thesis is to document the test conditions and procedures under which these tests were conducted and to document the outcomes from testing.A review of previous mesh testing established that the most common method used for the evaluation of mesh types was two-dimensional linear elastic analyses, often using catenary principles. These analysis techniques have been used to estimate the tension in the wires of mesh and the strength characteristics of the mesh. These methods assume that forces are only transferred along directly loaded wires and that failure of the mesh is only related to the tensile strength of the wire.The force – displacement response from fully restrained mesh tests conducted at the WASM test facility have been characterised into distinct phases, clearly demonstrating the non-linear behaviour of mesh. The initial force response to displacement is slow; however the force response increases dramatically with further displacement. This behaviour has been shown to follow a cubic relationship.The force – displacement results have also been used to develop load transfer concepts for both weld mesh and chain link mesh. These concepts suggest that forces are transferred away from the directly loaded wires through adjoining wires, distributing forces over a greater area of the mesh. The force capacity of the weld mesh is not only dependent on the tensile strength of the wire but also the quality of the welding process. Likewise, the force capacity of chain link mesh is not only dependent on the tensile strength of the wire but also diamond configuration which allows load to be shared across a greater area of mesh.Several other test conditions were evaluated as part of the test program, including mesh sheet overlaps and wire orientation. The results have demonstrated that the boundary conditions and mesh orientation alters the force – displacement response of mesh.Most current shotcrete testing techniques focus on quality assurance and quality control. Shotcrete support mechanism and failure mechanisms are complex and not well understood. The WASM punch test method was developed to evaluate shotcrete using realistic shotcrete failure mechanisms such as shear and flexural failure and adhesion loss.The behaviour of shotcrete is characterised by an initial stiff reaction followed by rupture of the cement matrix. Rupture generally occurs at displacements of less than 5mm. The rupture force of fibre reinforced shotcrete is dependent only on the cement content of the shotcrete mix and the thickness of the layer, and not on the fibre type. The post rupture reaction of shotcrete is dependent on the reinforcing material; namely fibres or mesh. Mesh reinforced shotcrete had much greater force and displacement capacity compared with fibre reinforced shotcrete.Membranes have two theoretical support models (Norcroft, 2006); namely, the membrane support model and the beam support model. A total of 6 tests were undertaken to investigate the behaviour of a particular membrane product under the two theoretical support models. These tests were aimed at determining a suitable test method that could determine the capacity of the membrane and the behaviour of the membrane under realistic loading conditions.The results from both test programs demonstrated that the membrane has limited force and displacement capacity and cannot be compared with conventional mesh and shotcrete as suggested in the product data sheet. The failure mechanism was shear failure with minimal adhesion loss observed.The development of the WASM test facility has enabled the evaluation and comparison of various surface support elements. The results of this testing have provide a valuable insight into the performance of each of the individual products.
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Vrba, Pavel. "Kalibrace nepřímých metod pro zjišťování vlastností alkalicky aktivovaných betonů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226970.
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This work solves creation of calibration relations to determine cube compressive strength, dynamic and static elastic modulus of alkali-activated concrete by non-destructive methods. Alkali-activated concrete is spoken of as a new material used in civil engineering. It shows different properties than normal concrete based on Portland cement. That's why the modification of common calibration relation seems necessary. Fresh concrete was made in the concrete plan ŽPSV a.s., Uherský Ostroh in three mixtures and always in the number of 18 cubes and 3 prisms. The samples were tested by impact hammer Schmidt type L, type N, SilverSchmidt PC-N and by ultrasound in 6 time periods of three specimens. After that, the cube compressive strength was determined. Status of static elastic modulus was determined in a time period of 28 days. The results are calibration relations to determine the progress of compressive strength and modulus of elasticity for each method and their combination.
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Bai, Yang. "Study of viscoelastic instabily in Taylor-Couette system as an analog of the magnetorotational instability." Thesis, Le Havre, 2015. http://www.theses.fr/2015LEHA0015/document.
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Cette thèse est consacrée à la vérification de l'analogie entre l'instabilité viscoélastique (VEI) et l'instabilité magnéto-rotationnel (MRI) dans un écoulement képlérien, afin de mieux comprendre le transport du moment dans les disques d'accrétion. Le discriminant de Rayleigh élasto-rotationnel est établi pour clarifier le rôle de l'élasticité dans le VEI. L'analyse de stabilité linéaire (LSA) avec le modèle d’Oldroyd-B est effectuée pour prédire les paramètres critiques des modes viscoélastiques. Il fait apparaître également l'influence de l'élasticité, la viscosité polymérique et d'autres paramètres de contrôle pour le VEI. Des expériences bien contrôlées avec des solutions aqueuses de polyoxyéthylène (POE) et de polyéthylène glycol (PEG) sont effectuées. Nous avons observé le mode stationnaire axisymétrique supercritique avec des solutions de faible élasticité et modes désordonnés sous-critiques avec des solutions de grande élasticité. Les formes et les valeurs critiques de ces modes sont en bon accord avec les prédictions théoriques de LSA. Selon l'analogie, le mode axisymétrique stationnaire est probablement l'analogue de MRI standard, tandis que le mode désordonné est probable que l'analogue de MRI hélicoïdale. La thèse contient aussi des résultats théoriques expérimentaux sur quatre autres régimes de rotation et un cas de limite d'élasticité infinieThis thesis is devoted to the verification of the analogy between the viscoelastic instability (VEI) and the magnetorotational instability (MRI) in a Keplerian flow, in order to get better understanding of the momentum transportation in accretion disks.The elasto-rotational Rayleigh discriminant is deduced to clarify the role of the elasticity in the VEI. The linear stability analysis (LSA) with Oldroyd-B model is performed to predict critical parameters of viscoelastic modes, and it reveals the influence of the elasticity, polymer viscosity on the VEI. Experiments with well controlled aqueous solutions of polyoxyethylene (POE) and polyethylene glycol (PEG) are conducted. We have observed supercritical stationary axisymmetric mode with solutions of small elasticity and subcritical disordered modes with solutions of large elasticity. Both the flow patterns and the critical values of these modes are in good agreement with the LSA predictions. According to the analogy, the stationary axisymmetric mode is likely the analog of the standard MRI while the disordered mode is likely the analog of the helical MRI. The thesis contains also theoretical and experimental results with four other rotation regimes and the limit case of infinite elasticity
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Heitz, Jean-François. "Propagation d'ondes en milieu non linéaire : applications à la reconnaissance des sols et au génie parasismique." Grenoble 1, 1992. http://www.theses.fr/1992GRE10120.
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La propagation d'ondes en milieu non lineaire est etudiee sur les plans theorique, experimental et numerique. Des applications touchant les domaines du genie parasismique et de la reconnaissance in situ des sols sont proposes. Apres un etat des connaissances acquises a ce jour sur le comportement du sol sous sollicitation dynamique, un modele de comportement viscoelastique non lineaire est introduit dans l'equation fondamentale de la dynamique. L'equation du mouvement du sol obtenue exhibe au second membre un terme de source contenant l'ensemble des termes caracteristiques lies a la non-linearite du sol. Une analyse dans l'espace des frequences montre que le comportement non lineaire deviatoire du sol est a l'origine de modifications du contenu spectral au cours de la propagation par rapport au contenu frequentiel de la sollicitation. Une methode iterative de resolution de l'equation du mouvement est utilisee. A chaque iteration, la solution est obtenue explicitement par l'utilisation de transformations fonctionnelles integrales appropriees. Deux essais dynamiques in situ en surface et en puits avec excitation harmonique sont interpretes sur la base de l'approche theorique precedente. Le premier essai a permis essentiellement de mettre en evidence in situ le comportement non lineaire du sol sous sollicitation sinusoidale. Pour le second essai, des calculs simulent la reponse du sol a distance du puits et une methode d'identification de parametres caracteristiques du comportement non lineaire du sol est proposee. Une autre application de l'approche theorique proposee permet d'etudier les effets de site unidimensionnels caracteristiques du comportement non lineaire d'un horizon de sol reposant sur un demi-espace et subissant une sollicitation transitoire de type sismiques. Une extension du calcul en configuration bidimensionnelle est ensuite proposee
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LIN, XIN-MAO, and 林新茂. "Linear elastic fracture analysis on arbitrarily inclined surface cracks." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/16289957349240094183.
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Carka, Dorinamaria. "Non-Linear Analysis of Ferroelastic/Ferroelectric Materials." 2012. http://hdl.handle.net/2152/19499.
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Abstract
Ferroelectric/ferroelastic ceramics are used in a range of smart structure applications, such as actuators and sensors due to their electromechanical coupling properties. However, their inherent brittleness makes them susceptible to cracking and understanding their fracture is of prominent importance.
A numerical study for a stationary, plane strain crack in a ferroelastic material is performed as part of this work. The stress and strain fields are analyzed using a constitutive law that accounts for the strain saturation, asymmetry in tension versus compression, Bauschinger effects, reverse switching, and remanent strain reorientation that can occur in these materials due to the non-proportional loading that arises near a crack tip. The far-field K-loading is applied using a numerical method developed for two-dimensional cracks allowing for the true infinite boundary conditions to be enforced. The J -integral is computed on various integration paths around the tip and the results are discussed in relation to energy release rate results for growing cracks and for stationary cracks in standard elastic–plastic materials.
In addition to the fracture studies, we examine the far field electromechanical loading conditions that favor the formation, existence and evolution of stable needle domain array patterns, using a phase-field modeling approach. Such needle arrays are often seen in experimental imaging of ferroelectric single crystals, where periodic arrays of needle-shaped domains of a compatible polarization variant coexist with a homogeneous single domain parent variant. The infinite arrays of needles are modeled via a representative unit cell and the appropriate electrical and mechanical periodic boundary conditions. A theoretical investigation of the generalized loading conditions is carried out to determine the sets of averaged loading states that lead to stationary needle tip locations. The resulting boundary value problems are solved using a non-linear finite element method to determine the details of the needle shape as well as the field distributions around the needle tips.text
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WU, PAI-HONG, and 吳派宏. "Non-linear analysis of elastic planar frames with members under transverse loadings." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/18622678660393164631.
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Huynh, Dinh Bao Phuong, Jaime Peraire, Anthony T. Patera, and Guirong Liu. "Real-Time Reliable Prediction of Linear-Elastic Mode-I Stress Intensity Factors for Failure Analysis." 2005. http://hdl.handle.net/1721.1/30374.
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Modern engineering analysis requires accurate, reliable and efficient evaluation of outputs of interest. These outputs are functions of "input" parameter that serve to describe a particular configuration of the system, typical input geometry, material properties, or boundary conditions and loads. In many cases, the input-output relationship is a functional of the field variable - which is the solution to an input-parametrized partial differential equations (PDE). The reduced-basis approximation, adopting off-line/on-line computational procedures, allows us to compute accurate and reliable functional outputs of PDEs with rigorous error estimations. The operation count for the on-line stage depends only on a small number N and the parametric complexity of the problem, which make the reduced-basis approximation especially suitable for complex analysis such as optimizations and designs. In this work we focus on the development of finite-element and reduced-basis methodology for the accurate, fast, and reliable prediction of the stress intensity factors or strain-energy release rate of a mode-I linear elastic fracture problem. With the use of off-line/on-line computational strategy, the stress intensity factor for a particular problem can be obtained in miliseconds. The method opens a new promising prospect: not only are the numerical results obtained only in miliseconds with great savings in computational time; the results are also reliable - thanks to the rigorous and sharp a posteriori error bounds. The practical uses of our prediction are presented through several example problems.Singapore-MIT Alliance (SMA)
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Lucking, William Michael. "Analysis of edge problems in statically-loaded fiber-reinforced laminated plates by linear elastic theory." Thesis, 1989. http://spectrum.library.concordia.ca/2509/1/NL49122.pdf.
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Liou, U. N., and 劉勇男. "Deterministic and Random Vibration Analysis of a Non-linear Beam on an Elastic Foundation Subjected to a Moving Load." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/41927625607328133016.
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碩士國立中興大學
應用數學研究所
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In this paper, the deterministic and random vibration analysis of a nonlinear beam on an elastic foundation subjected to a moving load, which may simulate railway track, runway, etc, has been performed. The effects of longitudinal deflection and inertia have been considered so that the coupled equations of longitudinal and transverse deflections can be derived based on Bernoulli-Euler hypothesis. The randomness of the beam profile has been considered in such a way that the mean line of the beam is variable with respect to position in the vertical plane and is superimposed by stochastic uncertainty, and the moving load travells along the beam with constant velocity or acceleration. The deterministic and statistical dynamic responses of the beam have been calculated by using the Galerkin's method in conjunction with the finite element method, and the derived nonlinear system differential equation has been solved by using the implicit direct integration method. In particular, the standard deviation of the transverse deflection of the nonlinear beam have been calculated and presented by using the Monte Carlo simulation technique. Besides, the distribution of the midpoint deflection of the beam has been investigated by using the probability paper plot.
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Mois, Joao Gabriel Ribeiro. "Modelação de estruturas mistas com aço e betão em edifícios." Master's thesis, 2020. http://hdl.handle.net/10316/94044.
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Dissertação de Mestrado Integrado em Engenharia Civil apresentada à Faculdade de Ciências e TecnologiaO presente documento é dividido em duas partes principais: uma referência bibliográfica para abordar a teoria acerca das estruturas mistas, e uma parte analítica. A referência bibliográfica abrange assuntos como o enquadramento histórico do estudo e utilização destes elementos e as principais soluções utilizadas no mercado atual para diversos elementos estruturais, além da apresentação das principais vantagens na utilização das estruturas mistas em projetos de edifícios. A parte principal da revisão bibliográfica é basicamente o levantamento da maioria dos pormenores que a norma europeia considera importante na fase de modelação de estruturas mistas, além da apresentação das diferentes possibilidades se tratando de análise estrutural e as diferenças entre análise fendilhada ou não fendilhada. No que diz respeito aos pormenores de modelação, sempre que possível foi exemplificado como são consideradas as diferentes situações através do software comercial Robot Structural Analisys. Após a revisão bibliográfica, são apresentados todos os modelos que foram analisados no software em causa. Primeiramente foram realizadas análises em vigas simplesmente apoiadas e isoladas de forma a encontrar as metodologias de modelação que geram modelos com os resultados mais próximos da realidade, buscando sempre a metodologia mais eficiente. Após comparar os resultados obtidos na primeira análise, foram escolhidas as modelações mais confiáveis e eficientes para serem utilizadas na análise de um edifício genérico. Foi modelado um edifício misto para cada metodologia em causa, comparando os resultados obtidos e então tirando conclusões acerca da eficiência destas metodologias.
The objective of this document is to present alternatives in regards structural modeling, its analysis and different composite solutions. In order to do so, the document is divided into twomain parts: a bibliographic review of composite structures theories, and an analytical part. The bibliographic review covers subjects like the historical framework of the study and use ofthese elements and the actual usual solutions of composite elements, in addition to the main advantages in the use of various composite solutions. The main part of the bibliographic reviewis a survey about the most important aspects considered by the European Regulation when modeling composite structures is presented as well as different options for a structural analysis, and the difference between cracked and un-cracked analysis. When the aspects of modeling are presented, whenever possible it was exemplified how the different situations are considered through the software Robot Structural Analysis. Following the bibliographic review, all models that were analyzed in the preparation of this document are presented. Focusing on the finding of the most efficient modeling methodology,combined with outcome models with realistic results, analysis where performed on beams with perfect hinge and isolated. After comparing the results, the most reliable and efficient modelswere chosen to be used in building project, therefore considered different methodologies. A composite building was then modeled for each explored methodology, comparing the resultsand drawing conclusions about the efficiency of these methodologies.
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Araújo, Vital Nai Quei Pereira. "Análise comparativa de modelos de cálculo de estruturas de betão armado." Master's thesis, 2013. http://hdl.handle.net/10316/38510.
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Dissertação de Mestrado Integrado em Engenharia Civil apresentada à Faculdade de Ciências e Tecnologia da Universidade de CoimbraNesta tese realizou-se uma abordagem não linear de uma viga contínua de betão armado, de dois tramos de um trabalho experimental anteriormente feito por Ana Maria S. Teixeira Bastos (1997, FEUP), e compara-se os resultados com programas comerciais de cálculo de elementos finitos. Na análise não linear utilizaram-se modelos elasto-plásticos e fendilhação para betão, aplicados através do Método de Elementos Finitos (MEF). Efectuou-se o dimensionamento de uma estrutura com modelos de análise-linear elástica com ou sem redistribuição. Comparou-se os resultados experimentais das vigas com os obtidos com os programas comerciais de software midas® FEA e Abaqus® CAE 6.10-1, usando elementos finitos bidimensionais, modelo elasto-plástico e modelo de fendilhação distribuída (“Smeared Crack”). E obteve-se conclusões relativas aos modelos utilizados, documentando de forma conveniente os casos de aplicação das ferramentas e modelos.
This thesis made an approach to linear and non-linear analysis of a reinforced concrete beam, the two spans of structure an experimental work previously done by Ana Maria S. Teixeira Bastos (1997, FEUP). The results were compared with commercial software’s of finite elements calculations. The elasto-plastic and smeared crack models are applied to twodimensional formulations of Finite Element Methods (FEM). The design of the structure considering the linear elastic behaviour with or without redistribution was made. The comparison of experimental results of beams with midas® FEA and Abaqus® CAE 6.10-1 commercial software´s was made, using two-dimensional finite elements with elasto-plasticity and the Smeared Crack models. The conclusions were made about the results obtained with the models used in the cases of application of the tools were documented in an appropriate way.
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Durães, Diogo André Santiago. "Caracterização estrutural de um equipamento de elevação de girders." Master's thesis, 2019. http://hdl.handle.net/10316/93541.
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Dissertação de Mestrado Integrado em Engenharia Mecânica apresentada à Faculdade de Ciências e TecnologiaA análise estrutural é um tema próspero na engenharia, uma vez que ao longo dos últimos anos tem surgido cada vez mais o desenvolvimento de algoritmos para a resolução de problemas estruturais. Estes algoritmos associados a um software, permitem a sua correta e eficiente utilização.O motivo do presente estudo é a análise estrutural de uma estrutura metálica elevatória que permite a movimentação de peças por ação de vácuo. A estrutura em análise, comparativamente com a fornecida originalmente pelo fabricante, sofreu uma alteração através da incorporação de uma treliça metálica, com o intuito de movimentar componentes da pá eólica de dimensões superiores às idealizadas pelo fabricante.A caraterização da estrutura com o aumento foi realizada através do método de elementos finitos utilizando o SolidWorks®. Para a correta definição de todos os parâmetros inerentes à modelação foi imprescindível a validação do modelo, através da realização de um teste experimental, que permitiu equiparar os deslocamentos da estrutura aos da modelação e atingir um erro de cerca de 5%.Os resultados obtidos para o regime linear-elástico demonstram que a inclinação que a estrutura sofre terá efeitos sobre as tensões sentidas por esta, uma vez que uma inclinação positiva provocará o aumento das tensões, e para uma inclinação contrária ocorre a diminuição das tensões sobre a estrutura. Ao mesmo tempo, foi verificado que praticamente toda a estrutura se manteria sobre o regime elástico, com a exceção de uma pequena região na qual ocorre a ligação entre a estrutura original e a nova, acontecendo apenas no caso mais crítico, cuja probabilidade de ocorrência é diminuta.
Structural analysis is a thriving topic in engineering, since over the last few years there has been a growing development of algorithms for solving structural problems. These algorithms associated with a software, allow for its correct and efficient use.The reason of the present study is the structural analysis of a metallic lifting structure that allows the movement of parts by vacuum action. The structure under analysis compared to the one originally provided by the manufacturer was changed by the incorporation of a metal truss in order to move components of the wind blade of dimensions larger than those idealized by the manufacturer.The characterization of the altered structure was performed using the finite element method using SolidWorks®. For the correct definition of all the parameters inherent to the modeling, it was essential to validate the model, by means of an experimental test, which made it possible to equate the displacements of the structure with those of the modeling and to achieve an error about 5%.The results obtained for the linear-elastic regime shows that the slope that which the structure undergoes will have effects on the stresses felt by this, since a positive slope will cause the increase of the stresses, and for a contrary slope the decrease of the stresses on the structure. At the same time, it was verified that the whole structure would remain on the elastic regime, with the exception of a small region in which the connection between the original structure and the new one occurs, occurring only in the most critical case, whose probability of occurrence is tiny.