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Objekt pro průmyslovou výrobu / The Building For Industrial ProductionMalý, Jan January 2017 (has links)
The subject of this diploma´s thesis is the design and assessment of steel structure two-bay building for industrial production. The width of the side aisles is 15 meters and the width of the main aisles is 35 meters. The length of industrial building is 90 meters. The height of the building is 17.4 meters. Steel structure of main aisles consists of main truss, the distance is 6 meters. The main truss consists of truss girder and fixed column. In the main aisles traversed, by bridge crane with a capacity of 20 tons. Steel structure of side aisles consists frame construction. The building for industrial production is designed for the area of Blansko.
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Lávka pro pěší / FootbridgeBlaška, Jan January 2017 (has links)
The subject of the final thesis is timber footbridge for pedestrians and cyclists over the Desna river in Loucna nad Desnou village. The length of the footbridge is 30 m, width 3 m and height is variable from 4 to 5 m. The footbridge is covered with roof inclination of 20° in transverse direction and the roof is arch in longitudinal direction. Roofing is metal sheet. The structure is three-dimensional truss consists of two truss connected by rafters, floor beams and by members of bracing. The 2D-truss consists of bottom chord, top arch chord and webs. There are end posts made of streel bracing frames. The material of structure is mostly glued laminated timber, then timber and steel. The steel is used for connectors and steel bracing frames.
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Byggnation av takstolar Lwengo Basilla : Tillverkning och beräkning av erforderliga dimensioner på takstolar för att uppnå en jämn och säker byggprocess i Demokratiska Republiken Kongo / Roof Truss Construction in Lwengo Basilla : A minor field study with focus on constructing and calculating required dimensions of roof trusses on a school in Democratic Republic of CongoDelshad Raouf, Schwan January 2014 (has links)
Denna rapport är en del av ett examensarbete på avdelningen för "Byggteknik och design" med inriktning "husbyggnad, projektering och konstruktion" på Kungliga Tekniska högskolan i Stockholm, Sverige. Rapporten handlar om byggandet av ett tak för en skolbyggnad i byn Lwengo Basilla som ligger i sydöstra delarna av Demokratiska republiken Kongo. Skolprojektet finansieras av en ideell organisation i Sverige som heter "Elikia na Biso" och leds av Miza Landström. Designen och konstruktionen av skolan har tagits fram med hjälp av studenter från olika avdelningar inom Kungliga Tekniska högskolan (KTH). En grupp studenter från KTH hjälpte till att lägga grunden och väggarna i skolan. Nästa grupp av studenter skickades för att hjälpa till med byggandet av skolans tak. Denna rapport fokuserar på att dimensionera och konstruera taket på skolan med hjälp av lokala material på ett effektivt sätt. Stegen för att bygga en geringslåda (precisionslåda), samt sågning och spikning av takstolen, och uppsättning av takstolarna på rätt plats har beskrivits i detalj. Virket som användes till takstolarna var mycket mer hållbara än vad som förväntades, och detta förstärker stabiliteten och säkerheten av hela taket. Taket på den första skolan blev klar, och de anställda kommer att bygga taket på den andra skolan själva med de erfarenheter de fått under byggandet av den första skolan. / This report is a part of a thesis in the department of “Construction engineering and Design” with specialization in “house building, planning and construction” at the Royal Institute of Technology in Stockholm, Sweden. The report is about the construction of a roof for a school building in the village of Lwengo Basilla located in south eastern parts of Democratic Republic of Congo. The school project is funded by a non-profit organization in Sweden named “Elikia na Biso” headed by Miza Landström. The design and construction of the school has been put forth with the help of students from different departments of the Royal Institute of Technology (KTH). A group of students from KTH helped to lay the foundation and the walls of the school. The next group of students was sent to help with the construction of the school roof. The focus of this report is to dimension and construct the roof of the school using local materials in an efficient way. The steps of constructing a mitre box(precision box), the sawing and nailing of the roof truss, and raising the roof trusses into place are all described in detail. The timber used for the roof trusses was much more durable than what was expected, this ensures the stability and safety of the roof. The roof of the first school was finished, and the workers will build the roof of the second school by themselves with the experience they gained during the construction of the first school.
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Strypų konstrukcijų prisitaikomumo analizė inkrementiniu-iteratyviniu metodu / An incremental-iterative method for shakedown analysis of bar structuresBlaževičius, Gediminas 17 June 2011 (has links)
Darbo tikslas – tampriųjų-plastinių strypų konstrukcijų (santvaros, rėmų), veikiamų kartotinės kintamosios apkrovos, prisitaikomumo proceso ir būvio įtempių ir deformacijų analizė optimalaus konstrukcijų projektavimo kontekste. Darbo aktualumas grindžiamas prisitaikančių konstrukcijų optimizavimo uždaviniuose figūruojančių standumo sąlygų-apribojimų kokybės gerinimo būtinumu. Prisitaikančių konstrukcijų deformacijų būvis priklauso nuo apkrovimo istorijos, o poslinkių ribojimui taikoma nepakankamai tiksli Koiterio sąlyga arba liekamųjų poslinkių influentinė matrica, nepagrįstai laikant, kad plastinio deformavimo procesas yra išimtinai holonominis. Anotuojamame darbe apkrovimo istoriją siūloma įvertinti, atliekant papildomą inkrementinę deformacijų būvio analizę. Tyrimai atlikti taikant idealiai tamprių plastinių santvarų ir rėmų techniškosios skaičiavimo teorijos prielaidas (maži poslinkiai ir deformacijos). Taikomi ekstreminiai energiniai mechanikos principai, matematinio programavimo teorija ir metodai. Inkrementinės analizės matematiniai modeliai sudaryti, besikeičiančias plastines deformacijas tapatinant su distorsijomis. Taip nustatomos konkrečios apkrovimo istorijos liekamųjų poslinkių kitimo maksimalios ir minimalios reikšmės. Gautieji rezultatai panaudoti optimizavimo uždavinių sprendiniams tikslinti ir, esant būtinumui, leidžiantys keisti pradines pagrindinio optimizavimo uždavinio sąlygas. Pateikti išsamūs skaitinių eksperimentų rezultatai. / The purpose of this work is analysis of stress-deformation state of perfectly elastic-plastic shakedown structures (truss, frames) subjected to repeated variable load in the context of optimal design. Relevance of this work is based on a need of improvement of accurateness of stiffness constrains in optimization problems of structures. Stress-deformation state of shakedown structures depends on its loading history, while for the restriction of displacements inaccurate Koiter’s condition or an influence matrix of residual displacements, on the wrong supposition that the process of plastic deformation is exclusively holonomic, is used. In this work is proposed to evaluate loading history by performing an additional incremental analysis of stress-deformation state. This research was performed invoking the assumptions of technical computing theory of perfectly elastic-plastic trusses and frames (small deformations and displacements). Mechanics extremum energy principles, mathematical programming theory and methods are applied. Mathematical models of incremental analysis are composed by indentifying volatile plastic deformations with distortions. Thus particular maximum and minimum values of residual displacements are found. Obtained results are used to verify optimal design problems solutions and change the restrictions of main optimimization problem if necessary. Comprehensive results of numerical experiments presented.
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Utformning av tak och möjligheter med automation av takstolstillverkning i trä / Design of roofs and possibilities with automation of the production of wooden trussesHalldén, Gustav, Örtenblad, Emelie January 2016 (has links)
Purpose: The purpose of this work is to increase the possibilities of designing building components for specific demands to increase the building’s value, and to investigate how the possibilities can be affected by automating the production process. Method: The theoretical framework, which this study is based on, was collected using literature studies and was thereafter combined with the empirics, which were retrieved from qualitative methods as interviews and planned observations. A case study was made of the building Ormhuset in Jönköping. Findings: The objective of this work is to investigate the possibilities for designing roofs by using new automation methods for the production process of wooden roof structures. This study implies that parametric design can be used to generate new innovative shapes and designs that are optimised according to specific criteria. Furthermore, an increased use of automation in the production process of wooden roof trusses result in cheaper roof trusses, regardless of their shapes. The generated optimized designs are therefore cheaper and easier to produce using more automation in the production process. Implications: If parametric design is used, almost any kind of shapes can be generated and optimised. To ensure manufacturability of a design, an early connection between architect and manufacturer is important. Furthermore, increased use of automation can lead to easier and faster production of roof trusses and investing in more automation can be relevant for companies with large production volumes. Using digital files to control the manufacturing machines is time saving. There are alternative manufacturing methods for advanced roof structurers in wood, which are better suited for production, which cannot be rationalized as for roof trusses. Constraints for increased automation are often a high investment cost and limited space. Limitations: If the study is performed on another case than Ormhuset and with other respondents, the result might have differed but could be similar, why this study is not generally valid but only shows one possible outcome. / Syfte: Syftet med detta arbete är att öka möjligheterna att utforma byggnadsdelar efter specifika behov för att öka en byggnads värde, samt undersöka hur möjligheterna kan påverkas genom att automatisera tillverkningsprocessen. Metod: Den teori som arbetet grundas på har samlats in via litteraturstudier och har därefter kombinerats med empiri som framkommit genom kvalitativa insamlingsmetoder i form av intervjuer och planerade observationer. En fallstudie av byggnaden Ormhuset i Jönköping har genomförts. Resultat: Målet med detta arbete är att studera möjligheter inom utformning av tak som ges av nya automationsmetoder vid tillverkning av takkonstruktioner i trä. Studien har visat att parametrisk design kan användas för att generera nya innovativa former och utformningar som är optimerade utefter specifika kriterier. Vidare kan ökad användning av automation vid tillverkning av takstolar i trä leda till billigare takstolar oberoende av form. De optimerade utformningar som tagits fram blir alltså billigare och lättare att tillverka vid en mer automatiserad tillverkningsprocess. Konsekvenser: Om parametrisk design används kan i stort sett vilka utformningar som helst tas fram och optimeras. För att säkerställa producerbarheten av en utformning är en tidig koppling mellan arkitekt och tillverkare viktig. Vidare kan en ökad automation medföra enklare och snabbare tillverkning av takstolar, och en investering i mer automation kan vara relevant för företag med stora produktionsvolymer. Används digitala produktionsfiler för att styra de tillverkande maskinerna kan tid sparas in. Det finns alternativa produktionssätt för avancerade takkonstruktioner i trä som är bättre lämpade då tillverkningen inte kan rationaliseras på samma sätt som för takstolar. Begränsande faktorer för en ökad automation är ofta en hög investeringskostnad och utrymmesbrist. Begränsningar: Om studien istället utförs för ett annat fall än Ormhuset och därmed med andra respondenter hade kunnat resultera i andra, men kanske snarlika, resultat, varför denna studie inte är generellt giltig utan enbart visar ett möjligt utfall.
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Análise numérica, via MEF, de ligações em treliças metálicas espaciais / Numerical analysis, using FEM, of connections in metallic space trussesSampaio, Taís Santos 01 October 2004 (has links)
As treliças espaciais vêm sendo freqüentemente utilizadas, de forma bastante diversificada, mas seu principal uso é como cobertura de grande vãos. Recentemente, vários acidentes com este tipo de estrutura têm acontecido, principalmente devido a uma série de considerações adotadas para dimensionamento, as quais não condizem com a realidade. Neste contexto, foi feito um estudo do comportamento seguido por estas estruturas. Este trabalho apresenta uma análise teórica, via método dos elementos finitos, de modelos de treliça espacial de seção tubular circular. Tem como objetivo verificar o comportamento de cada sistema de ligação, modelado tridimensionalmente com elementos de casca, associado à treliça espacial, modelada em elementos lineares. Foram estudadas as tipologias usuais de ligação deste tipo de estrutura abordando os problemas causados pelas peculiaridades de cada sistema. / Space trusses have been very frequently used in many applications, but its main employment is as roofs of great areas. Recently, many accidents have been occurring with this type of structure, mainly because of a series of adopted design assumptions, which does not fit reality. In this context, the behavior of this type of structure was studied. This study presents a theoretical analysis, using finite element method, of space trusses composed by circular tubular sections. It has as an objective to verify the behavior of each connection system, modeled in 3D by shell finite elements, associated to a space truss, modeled in linear finite elements. The usual typology of connections used in this kind of structure was studied, considering the problems caused by peculiarities of each system.
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A equação unidimensional de difusão de nêutrons com modelo multigrupo de energia e meio heterogêneo : avaliação do fluxo para problemas estacionários e de cinética / The one dimensional diffusion equation with multi group energy model and heterogeneous media: flux evaluation to stationary and kinetic problemsCeolin, Celina January 2014 (has links)
Na presente tese é resolvida a equação de difusão de nêutrons estacionária, bem como problemas de cinética, em geometria unidimensional cartesiana multi-região considerando o modelo de multigrupos de energia. Um dos objetivos e inovação neste trabalho é a obtenção de uma solução aproximada com estimativa de erro, controle de precisão e na forma de uma expressão analítica. Com esse tipo de solução não há a necessidade de recorrer a esquemas de interpolação, geralmente necessários em caso de discretizações do domínio. O fluxo de nêutrons é expandido em uma série de Taylor cujos coeficientes são encontrados utilizando a equação diferencial e as condições de contorno e interface. O domínio é dividido em várias células, cujo tamanho e o grau do polinômio são ajustáveis de acordo com a precisão requerida. Para resolver o problema de autovalor é utilizado o método da potência. A metodologia é aplicada em um benchmark que consiste na solução da equação de difusão como condição inicial e na solução de problemas de cinética para diferentes transientes. Os resultados são comparados com sucesso com resultados da literatura. A convergência da série é garantida pela aplicação de um raciocínio baseado no critério de Lipschitz para funções contínuas. Cabe ressaltar que a solução obtida, em conjunto com a análise da convergência, mostra a solidez e a precisão dessa metodologia. / In the present dissertation the one-dimensional neutron diffusion equation for stationary and kinetic problems in a multi-layer slab has been solved considering the multi-group energy model. One of the objectives and innovation in this work is to obtain an approximate solution with error estimation, accuracy control and in the form of an analytical expression. With this solution there is no need for interpolation schemes, which are usually needed in case of discretization of the domain. The neutron flux is expanded in a Taylor series whose coefficients are found using the differential equation and the boundary and interface conditions. The domain is divided into several layers, whose size and the polynomial order can be adjusted according to the required accuracy. To solve the eigenvalue problem the conventional power method has been used. The methodology is applied in a benchmark problem consisting of the solution of the diffusion equation as an initial condition and solving kinetic problems for different transients. The results are compared successfully with the ones in the literature. The convergence of the series is guaranteed by applying a criterion based on the Lipschitz criterion for continuous functions. Note that the solution obtained, together with the convergence analysis, shows the robustness and accuracy of this methodology.
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Design Optimization Of Truss Structures Using Genetic AlgorithmsUnalmis, Dilek 01 October 2012 (has links) (PDF)
Design optimization of truss structures is a popular topic in aerospace,
mechanical, civil, and structural engineering due to benefits to industry.
Common design problem for the structures is the weight minimization.
Especially in aerospace engineering the minimization of the weight of the total
structure gets the highest importance in the design.
This study focuses on the design optimization of 2D and 3D truss structures.
The objective function is the total mass of the structure which is subjected to
stress and nodal displacement constraints. To optimize the design, Genetic
Algorithm (GA) is preferred due to its efficiency in dealing with problems with
discrete design variables as in the case of truss structures. This technique
yields more realistic results than linear programming methods.
In the thesis, a finite element code is developed for the analysis of planar and
space truss structures. The developed finite element solver is coupled with a
genetic algorithm optimization code which is also developed as a part of the
thesis study. Different truss optimization case studies are performed to
demonstrate the performance of the finite element solver and the genetic
algorithm optimization code that are developed. It is shown that with the use
of adaptive penalty function employing scaled fitnesses, the arbitrariness
issue of the factor multiplying the error term in the augmented fitness
function can be resolved. It is also shown that significant weight reduction can
v
be achieved by employing shape optimization together with size optimization
compared to pure size optimization.
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Structural health monitoring the Traffic Bridge in Saskatoon using strain gaugesMacLeod, Alison Barbara 12 April 2011
The steel through-truss Traffic Bridge, located in Saskatoon, Saskatchewan is over one hundred years old. The bridge has been subject to ongoing maintenance throughout its service life. However, inspection reports from 2005 and 2006 highlighted
the severe deterioration experienced primarily by the steel members immediately above and below the deck surface. These reports prompted the City of Saskatoon (COS) to implement a rehabilitation project that involved the installation of a post-tensioning system to relieve the badly corroded bottom chord members of the axial loads due to the
self-weight of the structure, in 2006. Due to the severe deterioration and the structural modifications that the Traffic Bridge has endured, a limited scope structural health monitoring (SHM) system, based on strain measurements, was implemented to reduce some of the uncertainty regarding the active load paths occurring at the deck level.<p>
The objectives of the SHM study were to obtain more information regarding the actual load paths and ascertain possible types of structural redundancy, to determine how to best model this type of structure, and to find ways to track ongoing deterioration using instrumentation. The SHM study involved controlled truck loading scenarios to permit measurement of the load paths and provide data to compare the measured results to a finite element (FE) model of the instrumented span. In addition, random loading
scenarios were used to capture the vertical dynamic response of the structure in order to further refine the FE model.<p>
This study focused on the response of one-half of one interior span. A total of 72 strain gauges were installed. The downstream truss was highly instrumented at ten locations, three members of the upstream truss were instrumented to measure the distribution, and the floor joists in the downstream lane were instrumented to establish
possible redundancy paths.<p>
Using an FE model in combination with the measured strain data, it was found that redundant load paths only existed at the level of the deck. The bottom chord members experienced non-zero strains once the control vehicle was past the span, possibly indicating some level of redundancy. The members believed to relieve a
portion of the bottom chord tensile forces included the car joists, edge joists, and the
timber deck. The amount of force transferred from the bottom chord to the deck members was found by FE analysis to be highly related to the lateral stiffness of the floor beams.<p>
The FE model was adjusted to match the measured results by modifying various modelling parameters. The most important features of the model were that all deck elements were modelled to be located at the elevation of the bottom chord, that the lateral stiffness of the floor beams was reduced by 50% to best represent the transfer of forces to deck elements, and that the stiffness of bottom chord members was reduced to
80% of their pristine values. In combination with calibrated modification factors applied to the measured values, this FE model is believed to be a useful tool to represent the behaviour of the structure to assist in detecting further damage by modelling the strain differential between members, and components of members.
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Structural health monitoring the Traffic Bridge in Saskatoon using strain gaugesMacLeod, Alison Barbara 12 April 2011 (has links)
The steel through-truss Traffic Bridge, located in Saskatoon, Saskatchewan is over one hundred years old. The bridge has been subject to ongoing maintenance throughout its service life. However, inspection reports from 2005 and 2006 highlighted
the severe deterioration experienced primarily by the steel members immediately above and below the deck surface. These reports prompted the City of Saskatoon (COS) to implement a rehabilitation project that involved the installation of a post-tensioning system to relieve the badly corroded bottom chord members of the axial loads due to the
self-weight of the structure, in 2006. Due to the severe deterioration and the structural modifications that the Traffic Bridge has endured, a limited scope structural health monitoring (SHM) system, based on strain measurements, was implemented to reduce some of the uncertainty regarding the active load paths occurring at the deck level.<p>
The objectives of the SHM study were to obtain more information regarding the actual load paths and ascertain possible types of structural redundancy, to determine how to best model this type of structure, and to find ways to track ongoing deterioration using instrumentation. The SHM study involved controlled truck loading scenarios to permit measurement of the load paths and provide data to compare the measured results to a finite element (FE) model of the instrumented span. In addition, random loading
scenarios were used to capture the vertical dynamic response of the structure in order to further refine the FE model.<p>
This study focused on the response of one-half of one interior span. A total of 72 strain gauges were installed. The downstream truss was highly instrumented at ten locations, three members of the upstream truss were instrumented to measure the distribution, and the floor joists in the downstream lane were instrumented to establish
possible redundancy paths.<p>
Using an FE model in combination with the measured strain data, it was found that redundant load paths only existed at the level of the deck. The bottom chord members experienced non-zero strains once the control vehicle was past the span, possibly indicating some level of redundancy. The members believed to relieve a
portion of the bottom chord tensile forces included the car joists, edge joists, and the
timber deck. The amount of force transferred from the bottom chord to the deck members was found by FE analysis to be highly related to the lateral stiffness of the floor beams.<p>
The FE model was adjusted to match the measured results by modifying various modelling parameters. The most important features of the model were that all deck elements were modelled to be located at the elevation of the bottom chord, that the lateral stiffness of the floor beams was reduced by 50% to best represent the transfer of forces to deck elements, and that the stiffness of bottom chord members was reduced to
80% of their pristine values. In combination with calibrated modification factors applied to the measured values, this FE model is believed to be a useful tool to represent the behaviour of the structure to assist in detecting further damage by modelling the strain differential between members, and components of members.
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