Дисертації з теми "Linearly Elastic Analysis"
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Lee, J. Xiang (James Xiang) Carleton University Dissertation Engineering Mechanical. "Vibration analysis of linearly elastic non-conservative systems using integral equations." Ottawa, 1991.
Знайти повний текст джерелаPhạm, 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.
Повний текст джерелаUnal, 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.
Повний текст джерелаnal,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.
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.
Повний текст джерелаSEREBRENICK, 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.
Повний текст джерелаO 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.
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.
Повний текст джерелаIncludes 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.
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.
Повний текст джерелаMaster of Science
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.
Повний текст джерелаBellinger, 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.
Знайти повний текст джерелаOzen, 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.
Повний текст джерелаs 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
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.
Повний текст джерелаPang, 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.
Повний текст джерелаMaster 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.
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.
Повний текст джерелаHuang, Liping. "STATISTICAL METHODS IN MICROARRAY DATA ANALYSIS." UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_diss/795.
Повний текст джерелаBlignaut, 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.
Повний текст джерелаTorlak, 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.
Повний текст джерелаRODRIGUEZ, 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.
Повний текст джерелаCOORDENAÇÃO 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.
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.
Повний текст джерелаLe, 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.
Повний текст джерелаPluto, 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.
Повний текст джерелаAmireghbali, 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.
Повний текст джерелаDavid, Sergio Adriani. "Modelagem dinamica, simulação e validação experimental de estruturas flexiveis." [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265325.
Повний текст джерелаTese (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
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.
Повний текст джерелаs 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.
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.
Повний текст джерелаMasada, 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.
Повний текст джерелаRizik, Vivian. "Analysis of an elasto-visco-plastic model describing dislocation dynamics." Thesis, Compiègne, 2019. http://www.theses.fr/2019COMP2505.
Повний текст джерелаIn 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
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.
Повний текст джерелаSolomon, 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.
Повний текст джерелаBarsoum, 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.
Повний текст джерелаPaucar, Casas Walter Jesus. "Concepção otima de sistemas elasto-acusticos interiores acoplados." [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265126.
Повний текст джерелаTese (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
畔上, 秀幸, Hideyuki Azegami, 志強 呉 та 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.
Повний текст джерелаKurniawan, 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.
Повний текст джерелаKurniawan, Cyrilus Winatama. "Flexural behaviour and design of the new LiteSteel beams." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16674/.
Повний текст джерелаSchifani, Guido. "Forme et dynamique de boîtes quantiques sous contraintes élastiques." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4069/document.
Повний текст джерелаThe 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
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.
Повний текст джерелаTan, 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.
Повний текст джерелаmer 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
Baklouti, Sana. "Vibration Analysis and Reduction of Cable-Driven Parallel Robots." Thesis, Rennes, INSA, 2018. http://www.theses.fr/2018ISAR0034/document.
Повний текст джерелаThis 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
Morton, Ellen C. "Static testing of large scale ground support panels." Thesis, Curtin University, 2009. http://hdl.handle.net/20.500.11937/2067.
Повний текст джерелаVrba, 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.
Повний текст джерелаBai, 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.
Повний текст джерелаThis 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
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.
Повний текст джерелаLIN, XIN-MAO, and 林新茂. "Linear elastic fracture analysis on arbitrarily inclined surface cracks." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/16289957349240094183.
Повний текст джерелаCarka, Dorinamaria. "Non-Linear Analysis of Ferroelastic/Ferroelectric Materials." 2012. http://hdl.handle.net/2152/19499.
Повний текст джерелаtext
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.
Повний текст джерелаHuynh, 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.
Повний текст джерелаSingapore-MIT Alliance (SMA)
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.
Повний текст джерелаLiou, 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.
Повний текст джерела國立中興大學
應用數學研究所
82
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.
Mois, Joao Gabriel Ribeiro. "Modelação de estruturas mistas com aço e betão em edifícios." Master's thesis, 2020. http://hdl.handle.net/10316/94044.
Повний текст джерелаO 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.
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.
Повний текст джерелаNesta 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.
Durães, Diogo André Santiago. "Caracterização estrutural de um equipamento de elevação de girders." Master's thesis, 2019. http://hdl.handle.net/10316/93541.
Повний текст джерелаA 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.