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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Fringe Projection Technique for Deformation Measurements under Impact Loading

Rai, Mani Ratnam January 2017 (has links) (PDF)
High-resolution three-dimensional (3D) shape reconstruction of objects has huge potential for applications in the field of design, security, entertainment, biomedicine, industrial quality control etc. Of the available techniques, optical methods have the distinctive advantage of facilitating non-contact and non-intrusive measurements. Of late, integration of optical measurement system with the computer based data processing has improved the quality of the results. Of the available techniques, structured-light illumination (Fringe Projection) is the most effective, owing its simplistic experimental architecture and analysis. Traditional Fringe Projection techniques function with the use of fringes generated using interferometric methods. With the advent of digital light projectors, digitally generated fringes have taken the place of interferometry based fringes. Despite the technological advances that this field has witnessed over last couple of decades, digital fringe projection technique still suffers from various shortcomings. This thesis presents a strategic solution to the challenges faced by the technique in its application to out-of-plane deformation measurement of objects under impact loading. First part of the thesis reports the developmental work on building an LED-Grating based optical projection system for implementation of linear-fringe projection profilometry. Successful use of the developed system in measuring out-of-plane deformation experienced by multiple targets under impact loading with a time sapling of 20,000 frames per second is re-ported. However, for performing ballistic impact measurements using the liner-fringe projection method, an order of magnitude higher time-sampling is needed. This is due to the disadvantages associated with linear fringe projection technique: (1) results in wrapped phase map (2p ambiguity) estimation, and (2) the deformation/shift of the recorded fringe pattern in the modulation direction sets a limit on unambiguously measurable whole-plane displacement. Typically, fringe pitch dictates the limit of maximum detectable displacement, and thus to be able to capture larger deformation from the earlier state, coarser fringe pitch is required to be projected; while this adversely affects the resolution of measurement system. Hence, there is a need to develop a fringe projection system which has capability for whole-plane displacement without affecting the resolution and/or necessitating higher temporal-sampling. Circular Fringe Projection (CFP) technique is proposed in the second part of the thesis as a novel solution to address the above issues. CFP technique offers additional advantage of relaxing the temporal resolution requirements of the imaging system by decoupling the maximum measurable deformation rate and the frame rate of camera. A new image analysis method is also developed to extract the underlying phase distribution of the recorded circular-fringe patterns, as the conventionally used single-frame linear-fringe analysis methods are incompetent at demodulating the circular fringes. Experimental results obtained in 3D shape measurement and whole-field out-of-plane displacement measurements of a deforming object reported in this thesis, not only confirms the ability of the proposed CFP technique in overcoming the shortcomings of the widely used linear-fringe projection technique, but also its suitability for deployment in ballistic-impact measurements.
362

A influência das ações repetidas na aderência aço-concreto / The influence of repeated loads on the steel-concrete bond

Rejane Martins Fernandes 25 April 2000 (has links)
Este trabalho descreve o comportamento da aderência do concreto armado sob ações monotônicas e repetidas através de uma revisão bibliográfica e de ensaios de arrancamento padronizados. A influência de alguns parâmetros foi analisada, como diâmetro da armadura, tipo e amplitude de carregamento. Os resultados dos ensaios monotônicos foram comparados com as recomendações do CEB-FIP MC 1990, EUROCODE 2 e NB-1/78. Também foi realizada a análise numérica da aderência monotônica por meio de elementos finitos. Considerou-se a barra lisa, elementos de contato entre o aço e concreto e comportamento elástico-linear dos materiais; pois a ruína experimental da ligação ocorreu pelo corte do concreto entre as nervuras. A resistência monotônica da ligação ficou compreendida entre condições boas e ruins de aderência. Os resultados calculados de acordo com as normas foram muito diferentes em relação aos valores experimentais, e apresentaram uma dispersão muito grande. A força repetida ocasionou a perda de aderência pelo crescimento progressivo dos deslizamentos. Os modelos numéricos não representaram o comportamento experimental, devido à resposta força-deslizamento não-linear. / This research describes the bond behaviour in reinforced concrete under monotonic and repeated loading through a state-of-art and standard pull-out tests. The influence of some parameters was analysed as deformed bar diameter, type and amplitude of loading. The monotonic test results were compared with recommendations of CEB-FIP MC 1990, EUROCODE 2 and NB-1/78. The numerical analysis of monotonic bond was realized through finite elements. It was considered smooth bar, contact elements between the steel and concrete, and materials as of linear-elastic behaviour, because the experimental degradation of bond was caused by concrete between the ribs sheared off. The monotonic bond resistance resulted between good and bad bond conditions. The results calculated according to the codes were very different from the experimental values and very disperse. The repeated loading causes bond degradation by progressive increase of slip. The numerical specimens did not represent the experimental behaviour because of the non-linear load-slip response.
363

Resposta dinâmica dos reatores UASB (Upflow Anaerobic Sludge Blanket) submetidos a cargas senoidais / not available

Kátia Bakker Batista 16 November 2000 (has links)
Esta pesquisa consistiu na verificação do comportamento do reator UASB de bancada (volume igual a 10,5 litros), quando submetido a variações senoidais de vazão afluente, comparando-se com a eficiência no seu funcionamento com vazão constante, através de análises de amostras de afluentes e efluentes. O reator UASB utilizado foi montado no Laboratório de Processos Biológicos da EESC-USP dentro de uma câmara com temperatura constante de 30 ± 3°C, e alimentado com esgoto sintético, com DQO de 500 mg/l, 750 mg/l e 1000 mg/l. O reator foi inoculado em abril de 1999, com 3,5 litros de lodo anaeróbio proveniente de um reator compartimentado, também situado na EESC-USP. Devido à dificuldade de atingir um valor esperado para a eficiência de remoção de Matéria orgânica, foi dada nova partida no reator, em julho de 1999, desta vez com lodo proveniente de outro UASB. Após a segunda partida, o reator operou com vazão constante e DQO afluente em torno de 500 mg/l até setembro de 1999, com média de remoção de DQO bruta de 75% no período, passando-se, então, à fase de variação senoidal de vazão de forma que o máximo e o mínimo fossem de ±30%, ±45% e ±60% da vazão média. Para este regime, obteve-se 80% de eficiência média de remoção de DQO bruta. Os valores de pH, alcalinidade e ácidos voláteis foram praticamente constantes durante a operação. Os perfis de remoção de DQO ao longo do dia mostraram uma pequena queda na eficiência do reator, aproximadamente 1,5 vezes o tempo de detenção hidráulica médio (8 horas), após os máximos de vazão para o regime de variação de vazão de ±30% e ±45% e 2,5 vezes o tempo de detenção hidráulica médio, para variação e ±60%. O mesmo experimento foi repetido para DQO afluente de 1000 mg/l e obteve-se, em média, eficiências de 65% de remoção de DQO. / This research consisted in the UASB reactor performance verification when it was submitted to sine-based variations of loading rate, in comparison to its normal operation. The UASB reactor used was set up at the Biological Process Laboratory of EESC-USP, inside a camera with temperature of 30°C ± 3°C. It was fed with synthetic sewage (COD = 500, 750 and 1000 mg/l). After start-up, the reactor was operated with constant loading rate (COD = 500 mg/l) until September 1999. The organic matter removal average in this period was 75%. Then, it was initiated the phase of sine-based variation loading rate (±30%, ±45% and ±60%). In this regime, it was obtained a medium gross COD removal efficiency of 80%. The pH values, alkalinity and volatile acids were practically constant during the operation. The COD removal profiles during the day showed a subtle fall in the reactor efficiency after 1.5 times the medium hydraulic detection time, for the loading rate variation of ±30% and ±45%. For ±60% variation, the answer time was approximately 2.5 times the medium hydraulic detection time. The efficiency of gross COD removal stay however over 78,53% until the experiment 9, witch showed that the reactor can stand the loading rate variations. The efficiency of filtered COD removal decreased on the second experiment, came back to the initial values and decreased again. The values of variation didn\'t surpass 6,6% for gross COD and 8,43% for filtered COD.
364

Samonakládací přepravník balíků / Self-loading trailer for the round balers

Václavík, Lukáš January 2015 (has links)
This thesis deals with the conceptual solution of self-loading container on straw bales. It is the issue of these machines' distribution according to specified criteria at the beginning. Research part follows with describing the individual components cosequently included in the conceptual design. The third point is the design of the solution itself and its rationale. There are itemized individual structural components and visualization. The last part contains strength calculations for structural nodes.
365

Meta-heurísticas para problemas integrados de roteamento e carregamento de veículos / Meta-heuristics for integrated vehicle routing and loading problems

Santini, Luigi Tavolaro 23 February 2017 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2018-01-24T20:35:47Z No. of bitstreams: 1 Luigi Tavolaro Santini.pdf: 2357766 bytes, checksum: b70528f7db6bf88f1285744982eb4234 (MD5) / Made available in DSpace on 2018-01-24T20:35:47Z (GMT). No. of bitstreams: 1 Luigi Tavolaro Santini.pdf: 2357766 bytes, checksum: b70528f7db6bf88f1285744982eb4234 (MD5) Previous issue date: 2017-02-23 / The present work deals with the Capacitated Vehicle Routing Problem with Three-Dimensional Loading Constraints. This problem is difficult to solve exactly, still relatively little studied, but important in the logistics activities of movement, warehousing and transportation. This problem consists in minimizing the total traveled distance by a homogeneous fleet of vehicles that address the issue of deliveries of customer demands, in which these demands are composed of items that have three relevant spatial dimensions. The objective of the present work is to develop heuristic and metaheuristic algorithms to solve the problem in question. The algorithms are based on the Clarke & Wright and George & Robinson heuristics, and on the Iterated Local Search and Adaptive Large Neighborhood Search metaheuristics. In the proposed algorithm, the routing problem is firstly addressed by adapting the Clarke & Wright heuristic, creating routes that are used to verify the loading pattern, thus obtaining an initial solution. In the following, an extensive search in the solution neighborhood is applied with the Iterated Local Search metaheuristic. For the best results of this search, it is checked if the loading pattern is feasible using an adapted George & Robinson algorithm. If it is not feasible, the Adaptive Large Neighborhood Search metaheuristic is executed in an attempt to find a feasible solution to the loading problem. Instances from the literature are used to evaluate the efficiency of the developed methods. The results obtained for the routing problem individually were of paramount importance to ensure the effectiveness of the Iterated Local Search metaheuristic. For the loading problem individually, the tests were also satisfactory, allowing for several feasible loading patterns using the adapted George & Robinson algorithm and the Adaptive Large Neighborhood Search metaheuristic. The results obtained with the proposed algorithm for the integrated problem were also good, being very close to those in the literature and with computational time relatively lower. As perspectives for future research, it is intended to investigate more efficient ways of exploring the solution space of the integrated problem, as well as the use of other metaheuristics. / O presente trabalho trata do Problema de Roteamento de Veículos Capacitado com Restrições de Carregamento Tridimensional. Este é um problema de difícil solução exata, ainda relativamente pouco estudado, porém importante nas atividades logísticas de movimentação, armazenagem e transporte de produtos. Este problema consiste em minimizar a distância total percorrida por uma frota homogênea de veículos que supram a questão das entregas das demandas de clientes, em que tais demandas são compostas por itens que possuem três dimensões espaciais relevantes. O objetivo do presente trabalho consiste em desenvolver algoritmos heurísticos e meta-heurísticos para resolver o problema em questão. Os algoritmos são baseados nas heurísticas de Clarke & Wright e de George & Robinson, e nas meta-heurísticas Iterated Local Search e Adaptive Large Neighborhood Search. No algoritmo proposto, primeiro trata-se o problema de roteamento adaptando-se a heurística de Clarke & Wright, criando roteiros que são utilizados para a verificação do padrão de carregamento, tendo-se assim uma solução inicial. Em seguida, é aplicada uma busca extensiva na vizinhança com a meta-heurística Iterated Local Search. Para os melhores resultados desta busca, verifica-se se o padrão de carregamento é viável utilizando o algoritmo de George & Robinson adaptado. Nos casos em que não é viável, a meta-heurística Adaptive Large Neighborhood Search é executada na tentativa de se encontrar soluções viáveis para o problema de carregamento. Instâncias da literatura são utilizadas para avaliar a eficiência dos métodos desenvolvidos. Os resultados obtidos para o problema de roteamento separadamente foram de suma importância para assegurar a eficiência do meta-heurística Iterated Local Search. Para o problema de carregamento separadamente, os testes utilizando o algoritmo de George & Robinson adaptado e a meta-heurística Adaptive Large Neighborhood Search também foram satisfatórios, permitindo a obtenção de vários padrões de carregamento factíveis. Os resultados obtidos com o algoritmo proposto para o problema integrado também foram bons, sendo bastante próximos aos da literatura e com tempo computacional relativamente menor. Como perspectivas de pesquisas futuras, pretende-se estudar formas mais eficientes de se explorar o espaço de busca do problema integrado, bem como a utilização de outras meta-heurísticas.
366

Balisticky odolné betony / Ballistic-Proof Concretes

Koutný, Ondřej January 2019 (has links)
Doctoral thesis „Ballistic-proof concretes“ deals with description, design and development of material based on ultra-high performance fibre reinforced cementitious composite with increased ballistic resistance i.e. increased resistance against high-strain rate dynamic loading induced by interaction of high-velocity moving objects. High mechanical properties, essential for such a material, are reached especially by maximal reduction of water-to-binder coefficient using high-range water reducing agents, high-strength aggregates and dense structure by precise selection and dosage of raw materials in the recipe. The main goal is to prepare a methodology for design of such a materials, observation of material behaviour on ballistic loading and quantitative description of material response for protective structures design. Properties of designed materials within this thesis are comparing with properties of commercially available and commonly used cementitious composites in order to create a concept for material limits in the field of ballistic protection. This concept enables to estimate ballistic protection of present or newly-designed materials and structures.
367

Vysokovýklopná lopata pro nakladač / High loading shovel for loader

Rajdl, Marek January 2015 (has links)
This diploma thesis deals with design of the high loading shovel for the loader Komatsu WA380. The aim is to find constructional solutions of the high loading shovel for a minimal dumping height of 4 500 mm, for the bucket width of 3 000 mm and for the bucket volume of 5 m3. The thesis contains a brief description of the high loading shovel and description of basic constructional components. It also contains choices of basic constructional components, a calculation of the necessary force to tilt the bucket and a static analysis. Stress control of the bucket, the frame and the pegs forms the final part of the thesis. The thesis is accompanied by the necessary technical drawings.
368

Comportement des structures en nids d'abeilles sous sollicitations dynamiques mixtes compression/cisaillement et effet de l'orientation des cellules / Dynamic honeycomb behaviour under mixed shear-compression loading and in-plane orientation cells effect

Tounsi, Rami 11 March 2014 (has links)
Les nids d'abeille d’aluminium combinent légèreté et grande capacité d’absorption d'énergie. Ils sont alors de plus en plus utilisés dans les secteurs du transport (automobile, aéronautique …) pour contribuer conjointement à l’allègement structural et à la sécurité. Dans cette thèse, le comportement à l’écrasement des nids d'abeille est étudié en tenant compte de l'effet combiné de l'angle d'orientation dans le plan des cellules, de l’angle de chargement et de la vitesse de sollicitation, que la littérature ne relate pas. Un dispositif de chargement mixte compression/cisaillement est conçu pour mener l’étude expérimentale. L’analyse des résultats porte sur le pic initial d’effort, le plateau d’effort, ainsi que sur les modes de déformation. Les résultats montrent une augmentation de la résistance sous sollicitation dynamique dépendante de l’angle de chargement Ψ. Elle devient moins significative quand l’angle de chargement augmente jusqu’à atteindre un angle critique. Pour Ψ > Ψcritique, les réponses quasi-statiques sont même plus élevées que les réponses dynamiques. Une étude numérique est alors entreprise. Elle permet de comprendre ce phénomène qui est imputé aux mécanismes de déformation locaux des cellules. Les résultats numériques montrent également que l’effet de l’angle d’orientation □ dans le plan est plus prononcé sur la force tangentielle que sur la force normale, que cela influence également les modes d’effondrement et donc la réponse mécanique. Ces simulations numériques, couplées aux résultats expérimentaux, permettent alors de dissocier les composantes normale et tangentielle de la réponse des nids d’abeille et d’identifier les paramètres d'un critère macroscopique de résistance exprimé en fonction de la vitesse d'impact, de l'angle de chargement et de l'angle d'orientation dans le plan. Finalement, dans le but de réduire le coût des simulations numériques, un modèle élément fini (EF) réduit basé sur un critère de périodicité tenant compte de l'angle d'orientation dans le plan est proposé et son domaine de validité est évalué. / Aluminium honeycombs combine lightweight with an efficient energy absorption capability (specific energy). They are widely used as crash energy absorbing and protective structures in a wide range of transport applications (automotive, aircraft …) to reduce energy consumption and greenhouse gas emission. Reducing vehicle mass has however to be done while at least maintaining the same safety levels. In this thesis, the honeycomb behaviour is investigated under mixed shear-compression loadings taking into account the combined effect of the in-plane orientation angle and the impact velocity, which has not been deeply investigated in the literature. Experimental study based on an improvement of a mixed shear-compression loading device is realised. Experimental analysis focuses on the initial peak and average crushing forces as well as the deforming pattern modes. Comparing quasi-static and dynamic results, a dynamic enhancement depending of the loading angle Ψ is observed under mixed shear-compression loading until a critical loading angle (Ψcritical). Beyond, a negative enhancement is observed. Thus, a numerical study is carried out. The negative enhancement phenomenon is attributed to the collapse mechanisms which are affected by the loading angle Ψ. Numerical results also highlight that the in-plane orientation angle has an effect on the collapse mechanisms and consequently on the mechanical response. This effect is more pronounced on the tangential force than the normal force. The combined effect of the in-plane orientation angle and the loading angle is analysed on the three identified deforming pattern modes. Combining numerical and experimental results, the average crushing normal and shear forces are dissociated. Therefore, the parameters of a macroscopic yield criterion for the mixed shear-compression honeycomb behaviour depending of the impact velocity, the loading angle and the in-plane orientation angle are identified. Finally, in order to optimise the cost in CPU-time of the numerical simulation, a reduced FE model based on the periodicity procedure taking into account the in-plane orientation angle is proposed and its validity range is evaluated.
369

Tailored Preloading, Precaching and Prefetching Loading Strategies for Applications Through a Multi-Component AI

Öfver, Martin January 2022 (has links)
When using a personal computer the user could experience starting an application for the first time, loading a level in a video game or any tedious arbitrary loading process. These loading processes often load mostly the same data each time and consume time where the user is waiting. Making it faster is often preferred. The file-caching tactics Preloading, Precaching and Prefetching (PPP) have received past research, mostly to make generic improvements or better algorithms. The gap in the work is a lack of non-generic file-caching optimisation algorithms. To improve loading times during a Mostly Deterministic File-Loading Process (MDFLP), this research suggests a Multi-Component Artificial Intelligence (MCAI) that analyses the application's runtime results. The proposed MCAI would not be a one size fits all kind of solution but rather generate a tailored File-Loading Strategy (FLS) for the application. The aim of the research is to investigate if a MCAI could improve loading speeds of arbitrary application's MDFLPs. The objectives are to implement a test synthesiser for generating synthetic test environments to use MCAI on, to implement the MCAI and perform the experiments. The research questions regard how the MCAI can analyse inefficient operations during a MDFLP, propose measures that increase efficiency and aid developers independently of the high-level technology used. They also regard how the MCAI through iterative runs of an application can generate an application-specific FLS which is better in terms of PPP performance. The method section goes into detail about how the test synthesiser, the MCAI and the host application is implemented. It also explains how the experiment was made, what the experiment tested, what data was collected and what hardware and software were used. The result first shows in detail how the MCAI works on a simple test and then moves on to three extensive tests. Two of the tests show positive results, where the MCAI manages to generate an optimal FLS, whilst the MCAI fails in the third test. The third test highlights inherent weaknesses in the MCAI. The conclusion is that the MCAI shows potential. In its weakest form, it still manages to produce good results, where the MCAI generates a FLS that improves the load time performance. There is improvement potential for the MCAI to make it more smart, efficient, reliable and make it able to generate a FLS for test three. The research leaves room for follows ups and projects, like developing the MCAI further and performing case studies. / När en dator används kan användaren uppleva starten av en applikation för första gången, inladdningen av en nivå i ett TV-spel eller någon tråkig, godtycklig inladdningsprocess. Dessa laddningsprocesser laddar ofta mestadels samma data varje gång och förbrukar tid där användaren väntar. Att göra det snabbare är ofta att föredra. Det har tidigare forskats om filcachningstaktikerna Preloading, Precaching och Prefetching (PPP), mest för att göra generiska förbättringar eller bättre algoritmer. Klyftan i forskningen är bristen på icke-generiska filcachande-optimeringsalgoritmer. För att förbättra laddningstiderna under en övervägande deterministisk filladdningsprocess (MDFLP), föreslår denna forskning en Multi-Komponents Artificiell Intelligens (MCAI) som analyserar programmets körtidsresultat. Den föreslagna MCAIn skulle generera en skräddarsydd filladdningsstrategi (FLS) för applikationen. Syftet med forskningen är att upptäcka om en MCAI kan förbättra laddningshastigheterna för godtyckliga applikationers MDFLP:er. Målen är att implementera en testsyntetiserare för att generera syntetiska testmiljöer att använda MCAI på, att implementera MCAI och utföra experimenten. Forskningsfrågorna handlar om hur MCAI kan analysera ineffektiva operationer under en MDFLP, föreslå åtgärder som ökar effektiviteten och hjälper utvecklare oberoende av vilken högnivåteknik som används. Det handlar också om hur MCAI genom körningar av en applikation kan generera en FLS som är bättre i PPP-prestanda. Metodavsnittet går in i detalj om hur testsyntesen, MCAI och värdapplikationen implementeras. Den förklarar också hur experimentet gjordes, vad experimentet testade, vilken data som samlades in och vilken hårdvara och mjukvara som användes. Resultatet visar först i detalj hur MCAI fungerar på ett enkelt test och går sedan vidare till tre omfattande tester. Två av testerna visar positiva resultat, där MCAI lyckas generera en optimal FLS, medan MCAI misslyckas helt i det tredje testet. Det tredje testet belyser inneboende svagheter i MCAI. Slutsatsen är att MCAI visar potential. Det finns förbättringspotential för MCAI för att göra den mer smart, effektiv, pålitlig och lyckas generera en bra FLS för test tre. Forskningen lämnar utrymme för uppföljningar och projekt, som att vidareutveckla MCAI och utföra fallstudier.
370

Development of Novel Computational Simulation Tools to Capture the Hysteretic Response and Failure of Reinforced Concrete Structures under Seismic Loads

Moharrami Gargari, Mohammadreza 26 July 2016 (has links)
Reinforced concrete (RC) structures constitute a significant portion of the building inventory in earthquake-prone regions of the United States. Accurate analysis tools are necessary to allow the quantitative assessment of the performance and safety offered by RC structures. Currently available analytical approaches are not deemed adequate, because they either rely on overly simplified models or are restricted to monotonic loading. The present study is aimed to establish analytical tools for the accurate simulation of RC structures under earthquake loads. The tools are also applicable to the simulation of reinforced masonry (RM) structures. A new material model is formulated for concrete under multiaxial, cyclic loading conditions. An elastoplastic formulation, with a non-associative flow rule to capture compression-dominated response, is combined with a rotating smeared-crack model to capture the damage associated with tensile cracking. The proposed model resolves issues which characterize existing concrete material laws. Specifically, the newly proposed formulation accurately describes the crack opening/closing behavior and the effect of confinement on the strength and ductility under compressive stress states. The model formulation is validated with analyses both at the material level and at the component level. Parametric analyses on RC columns subjected to quasi-static cyclic loading are presented to demonstrate the need to regularize the softening laws due to the spurious mesh size effect and the importance of accounting for the increased ductility in confined concrete. The impact of the shape of the yield surface on the results is also investigated. Subsequently, a three-dimensional analysis framework, based on the explicit finite element method, is presented for the simulation of RC and RM components under cyclic static and dynamic loading. The triaxial constitutive model for concrete is combined with a material model for reinforcing steel which can account for the material hysteretic response and for rupture due to low-cycle fatigue. The reinforcing steel bars are represented with geometrically nonlinear beam elements to explicitly account for buckling of the reinforcement. The strain penetration effect is also accounted for in the models. The modeling scheme is validated with the results of experimental static and dynamic tests on RC columns and RC/RM walls. The analyses are supplemented with a sensitivity study and with calibration guidelines for the proposed modeling scheme. Given the computational cost and complexity of three-dimensional finite element models in the simulation of shear-dominated structures, the development of a conceptually simpler and computationally more efficient method is also pursued. Specifically, the nonlinear truss analogy is employed to capture the response of shear-dominated RC columns and RM walls subjected to cyclic loading. A step-by-step procedure to establish the truss geometry is described. The uniaxial material laws for the concrete and masonry are calibrated to account for the contribution of aggregate interlock resistance across inclined shear cracks. Validation analyses are presented, for quasi-static and dynamic tests on RC columns and RM walls. / Ph. D.

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