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Feng, Ran. "Design of cold-formed stainless steel tubular joints". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41290628.
Pełny tekst źródłaZhou, Feng. "Web crippling of cold-formed stainless steel tubular sections". Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37228316.
Pełny tekst źródłaFeng, Ran, i 馮然. "Design of cold-formed stainless steel tubular joints". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41290628.
Pełny tekst źródłaUygar, Celaletdin. "Seismic Design Of Cold Formed Steel Structures In Residential Applications". Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607294/index.pdf.
Pełny tekst źródłaetin Yilmaz May 2005, 82 pages In this study, lateral load bearing capacities of cold formed steel framed wall panels are investigated. For this purpose lateral load bearing alternatives are analyzed numerically by computer models and results are compared with already done experimental studies and approved codes. In residential cold formed steel construction, walls are generally covered with cladding material like oriented strand board (OSB) or plywood on the exterior wall surface and these sheathed light gauge steel walls behave as shear walls with significant capacity. Oriented strand board is used in analytical models since OSB claddings are most commonly used in residential applications. The strength of shear walls depends on different parameters like screw spacing, strength of sheathing, size of fasteners used and aspect ratio. SAP2000 software is used for structural analysis of walls and joint force outputs are collected by Microsoft Excel. The yield strength of shear walls at which first screw connection reaches its shear capacity is calculated and load carrying capacity per meter length is found. The nonlinear analysis is also done by modeling the screw connections between OSB and frame as non-linear link and the nominal shear capacities of walls are calculated for different screw spacing combinations. The results are consistent with the values in shear wall design Guide and International Building Code 2003. The other lateral load bearing method is flat strap X-bracing on wall surfaces. Various parameters like wall frame section thickness, flat strap area, aspect ratio and bracing number are investigated and results are evaluated. The shear walls in which X-bracing and OSB sheathing used together are also analyzed and the results are compared with separate analyses.
Davies, Russell John. "The behaviour of press-joining in cold-formed steel structures". Thesis, University of Edinburgh, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.534541.
Pełny tekst źródłaZhou, Feng, i 周鋒. "Web crippling of cold-formed stainless steel tubular sections". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37228316.
Pełny tekst źródłaZhao, Wen-Bin. "Behaviour and design of cold-formed steel hollow flange sections under axial compression". Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16909/1/Wen-Bin_Zhao_Thesis.pdf.
Pełny tekst źródłaZhao, Wen-Bin. "Behaviour and design of cold-formed steel hollow flange sections under axial compression". Queensland University of Technology, 2006. http://eprints.qut.edu.au/16909/.
Pełny tekst źródłaCheng, Shanshan. "Fire performance of cold-formed steel sections". Thesis, University of Plymouth, 2015. http://hdl.handle.net/10026.1/3316.
Pełny tekst źródłaShamim, Iman. "Seismic design of lateral resisting cold-formed steel framed (CFS) structures". Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=117113.
Pełny tekst źródłaDispositions de conception sismique pour les murs de contreventement encadrés de l'acier formé à froid (CFS) ou gainés en bois sont disponibles dans les normes AISI S213-07. Toutefois, le Code national du bâtiment du Canada (NBCC), la CSA S136 et les normes AISI S213, à l'heure actuelle, ne répondent pas à la conception sismique pour les murs de contreventement encadrés en CFS pour utilisation au Canada. La directive existante sur la conception des murs de contreventement encadrés en CFS est basé sur les données obtenues à partir des essais statiques menés sous les protocoles de chargement cyclique monotones et aussi inversées.Cette recherche visait à élaborer des dispositions de conception sismique pour les murs de contreventement encadres en CFS comme une partie du système de résistance contre des forces sismiques de bâtiment. Ces conceptions peuvent être inclus dans le NBCC et AISI S213. Cette approche a consisté les essais avec la table de vibration sur les murs de contreventement, sur une ou deux étages, encadrés en CFS ou gainés en bois, la modélisation numérique des murs de contreventement, et enfin, analyses non linéaires dynamiques de construction de archétypes suivant la méthodologie de la Federal Emergency Management Agency (FEMA) P695. Au total, sept murs de contreventement gainés en bois et dix encadrés en CFS ont été mesurées en utilisant la table de vibration au laboratoire de structure de l'Ecole Polytechnique de Montréal. Les échantillons de mur étaient de pleine échelle en simple ou double étages et, la plupart, ont été faites avec un blocage dans le cadre CFS. Un mur de contreventement gainé en bois a été testé avec un panneau de gypse dans un côté de l'échantillon afin d'étudier des effets des éléments non structurels. L'essai dynamique a compris des testes de choc, de vibration harmonique forcée, et de mouvement du sol, représentant le danger sismique au Québec et à Vancouver, au Canada. La performance sismique des murs de contreventement, c'est à dire la force contre le comportement hystérétique de déplacement des modes de défaillance, était essentiellement similaire aux essais statiques. Inclusion du blocage augmente la résistance des murs de contreventement de près de 50%. Le logiciel OpenSees a été utilisé pour la modélisation numérique des murs qui était dynamiquement testés. Le comportement inélastique des murs de contreventement a été reproduit en utilisant le matériel Pinching04; des éléments de ressort supplémentaire de longueurs zéro ont été inclus dans le modèle pour représenter la rigidité du cadre, de la tige d'ancrage et le cadrage CFS. Les modèles des murs ont été calibrés sur la base des résultats des essais dynamiques, ainsi que les données obtenues par la calibration des testes statistiques qui obtenues auparavant. En outre, pour fournir des données expérimentales pour compléter la procédure de calibration du modèle, une série de tests statiques a été fait sur des cadres en CFS bloqués et les connexions stud-to-track. Les bâtiments (douze au total) étaient en deux, quatre, et cinq étages de type commercial et résidentiel à Halifax, Montréal et Vancouver, au Canada. Les bâtiments conçus avec Rd = 2.0 et Ro = 1.3 satisfait aux exigences de capacité d'effondrement FEMA P695. L'inclusion de panneau de gypse dans deux des bâtiments archétype augmente le ratio de CMR de 20% en moyenne.
Sapiee, Siti Fairuz Binti. "Behaviour and strength of screw connections in cold-formed steel structures". Thesis, Curtin University, 2013. http://hdl.handle.net/20.500.11937/1367.
Pełny tekst źródłaLui, Wing Man. "Design of cold-formed high strength stainless steel tubular columns and beam-columns /". View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202004%20LUI.
Pełny tekst źródłaIncludes bibliographical references (leaves 149-154). Also available in electronic version. Access restricted to campus users.
Blum, Hannah Beth. "Long-Span Cold-Formed Steel Double Channel Portal Frames". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/16290.
Pełny tekst źródłaYoung, B. (Ben). "The behaviour and design of cold-formed channel columns". Thesis, Faculty of Engineering, 1997. http://hdl.handle.net/2123/13673.
Pełny tekst źródłaRinchen. "Long-span cold-formed steel single C-section portal frames". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/18882.
Pełny tekst źródłaRasmussen, Kim J. R. "Stability of thin-walled structural members and systems". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/18194.
Pełny tekst źródłaHenriques, De Sena Cardoso Francisco Manuel. "System reliability-based criteria for designing cold-formed steel structures by advanced analysis". Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/14498.
Pełny tekst źródłaWilkinson, Simon James. "An investigation into the behaviour of steel proprietary support structures". Thesis, Nottingham Trent University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369256.
Pełny tekst źródłaGunawan, Leonardus. "Numerical models to simulate the thermal performance of LSF wall panels". Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/49856/1/Leonardus_Gunawan_Thesis.pdf.
Pełny tekst źródłaMorello, Denise. "Seismic performance of multi-storey structures designed with cold-formed steel wood sheathed shear walls". Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40764.
Pełny tekst źródłaLa construction de structures en acier formé à froid est beaucoup utiliser au Canada dans le secteur résidentiel et commercial. De plus, les murs de refends créés à l’aide des panneaux de bois faisant déjà parti du bâtiment sont un système efficace pour résister les forces latérales provenant d’un séisme. Malgré l’aspect pratique présenté par ces murs de refends, le Code National du Bâtiment du Canada (CNB) et la norme CSA S136 de l’Association Canadienne de Normalisation ne fournissent aucune directive pour leur conception. Pourtant, une limite de 20 mètres pour la hauteur et des facteurs de modification de force (Rd, Ro) compatible avec le CNB ont été incluses par l’American Iron and Steel Institute dans la norme américaine, AISI S213. Cette norme adresse la conception des systèmes de reprise des forces latérales en acier formé à froid. L’importance de valider les directives incluses dans le AISI S213 avec des analyses dynamiques et des essais dynamiques était la motivation derrière cette recherche.Quatorze structures (4, 6 & 7 étages) ont été conçues et ensuite modélisées à l’aide de deux logiciels : Ruaumoko et SAPWood. Deux systèmes de murs de refends ont été traités : un système constitué de murs de refends en acier formé à froid avec des panneaux de bois (Rd = 2.5 and Ro =1.7) et un autre système comprenant de ces mêmes murs de refends mais travaillant avec les murs de gypse (Rd = 1.5 and Ro =1.7). De plus, deux régions de forte séismicité, Montréal, QC et Vancouver, BC, ont été incluses dans la recherche. La performance de ces structures a été évaluée selon l’ATC-63, développé pour le Federal Emergency Management Agency (FEMA) au États-Unis.Le niveau de performance des modèles, déterminé selon le ATC-63, a confirmé la réussite de ces deux systèmes. Les murs ont démontré une résistance au cisaillement suffisante alors qu’ils étaient soumis à 45 séismes calibrés au-delà
Li, Xilin. "Modal decomposition of instabilities and its applications in analysis and design of cold-formed steel structures". Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/18962/.
Pełny tekst źródłaKoen, Damien Joseph. "Structural Capacity of Light Gauge Steel Storage Rack Uprights". Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/3880.
Pełny tekst źródłaKoen, Damien Joseph. "Structural Capacity of Light Gauge Steel Storage Rack Uprights". University of Sydney, 2008. http://hdl.handle.net/2123/3880.
Pełny tekst źródłaThis report investigates the down-aisle buckling load capacity of steel storage rack uprights. The effects of discrete torsional restraints provided by the frame bracing in the cross-aisle direction is considered in this report. Since current theoretical methods used to predict the buckling capacity of rack uprights appear to be over-conservative and complex, this research may provide engineers an alternative method of design using detailed finite element analysis. In this study, the results from experimental testing of upright frames with K-bracing are compared to finite element predictions of displacements and maximum axial loads. The finite element analysis is then used to determine the buckling loads on braced and un-braced uprights of various lengths. The upright capacities can then be compared with standard design methods which generally do not accurately take into account the torsional resistance that the cross-aisle frame bracing provides to the upright. The information contained in this report would be beneficial to engineers or manufacturers who are involved in the design of rack uprights or other discretely braced complex light gauge steel members subject to axial loads.
Talebian, Nima. "Upright Frame Shear Stiffness and Upright Biaxial Bending in the Design of Cold-Formed Steel Storage Rack-Supported Buildings". Thesis, Griffith University, 2018. http://hdl.handle.net/10072/381685.
Pełny tekst źródłaThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
Full Text
Freitas, Márcio Felix de. "Ligações metálicas constituídas por parafusos auto-atarraxantes". Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-22032016-101755/.
Pełny tekst źródłaThe use of screws in steel connections has increased significantly in recent years, mainly as connecting devices between light-gage components in steel construction, as, for example, in joints between metal roofing and purlins. These connections exhibit different failure modes from those displayed by conventional bolted connections, due to the type of fastener and the reduced thicknesses of the connected elements, defined as pull-out and pull-over. In Brazil, the lack of specific studies of this theme was one of the reasons for the omission of specific procedures for the design of screw connections from the new edition of the brazilian code for cold-formed steel members - NBR 14762:2001. The work reported here involved a comprehensive study of steel connections using screws, with emphasis on the sheating-purlin connection. A presentation is made of the procedures and recommendations of the main foreign codes, as well as of standardized tests for characterizing screws and evaluating the structural behavior and strength of connections. Also presented are the results of an experimental investigation based on the standard test of the AISI (1996) (American Iron and Steel Institute) applied to 27 test specimens with varying screw diameters and connector component thicknesses (purlin and sheeting), whose main purpose was to evaluate the AISI\'s design equations (2001b e 1996). To conclude, a report is made of the difficulties associated with the standard test, which, despite its simple conception, leads to considerably variable results, indicating the need for the adoption of more representative and reliable tests.
Mendes, Cristiane Lopes. "Estudo teórico de perfis formados a frio em situação de incêndio". Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-05042016-134851/.
Pełny tekst źródłaThe interest in design of steel structures in fire situation carried out in consequence of publication of Brazilians codes ABNT/NBR 14323:1999 named \"Steel structures fire design - Procedure\" and ABNT/NBR 14432:2000 \"Fire-resistance requirements for building construction elements - Procedure\". When the steel is exposed to elevated temperatures (for example, fire situation) reductions in the strength and deformation properties must be considered. In this sense, the code ABNT/NBR 14432:2000 prescribes values of parameter TRRF (Fire strength required time), with are used for design of steel structures using a simplified method prescribed in ABNT/NBR 14323:1999, or specifying fireproofing. However, this last code doesn\'t prescribe a simplified method for cold-formed steel in fire condition, and the fireproofing materials largely used in Brazil are the sprays, which are not appropriate to cold-formed profiles. In this sense, the main goal of the present work is show a brief context about steel structures in fire conditions, in special cold-formed profiles in room temperature and fire situation, and many types of fire protection materials used in steel structures and its applications. Finally, is suggested a design method to cold-formed profiles in fire, adopting the code ABNT/NBR 14762:2001 \"Design of cold-formed steel structures\", in which appropriate adaptations are considered, as well as a protection procedure to this profiles in fire conditions.
Júnior, Enio Carlos Mesacasa. "Comportamento estrutural e dimensionamento de cantoneiras de aço formadas a frio submetidas à compressão". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-17052012-093741/.
Pełny tekst źródłaOn the well known behavior of equal-leg angle columns, some questions apparently paradoxical have been reported in experimental results from several authors, including the occurrence of different instability modes from the expected by the elastic stability analysis, and maximum axial compressive load expressly different (generally conservative) from theoretical previsions. Therefore, the aim of this work is to improve the knowledge about the equal-leg angle columns behavior, contributing to the understanding of the features that complicate the interpretation of experimental results, among which, the longitudinal distance between the end sections and the center of hinges (pin-ended columns), and also the direction of the minor-axis flexural initial imperfection, which proved to play a key role in the post-critical column behavior, specially for column lengths near of the transition between global buckling modes (major-axis flexural-torsional and minor-axis flexural modes). On this range of lengths, different modal interaction amplitudes can be obtained, only with the direction of the minor-axis flexural initial imperfection (i.e., the amplitude of this imperfection plays a negligible influence on the column behavior). Furthermore, putting together a fairly large column ultimate strength data bank comprising experimental test results performed by several authors, collected from the available literature, and new experimental results on fixed-ended angle columns performed in this work, important comparisons with theoretical studies can be showed as well as evaluation of several ultimate strength theoretical prevision procedures, either those suggested by another authors as those arising from interpretations of normative procedures in the light of theoretical behavior verified in the first stage of labor. In conclusion, only one procedure based on Direct Strength Method and two procedures based on Effective Width Method exhibited accurate results, all of which neglecting the flexural-torsional mode as a global mode. Thus, it is important to mention that some additional studies are needed, because if adopted a procedure based only in the minor-axis flexural mode, despite being statistically advantageous, it is verified the possibility to occurs quite unconservative results.
Javaroni, Carlos Eduardo. "Perfis de aço conformados a frio submetidos à flexão: análise teórico-experimental". Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-11122017-112750/.
Pełny tekst źródłaNowadays, the cold-formed steel members have intense application as structural elements in constructions and, in consequence, they are subjected to several types of loads. This work presents the general aspects of the study of cold-formed steel members subjected to flexion used as beams and, also, as purlins. Sections of type U, type C and type Z are analysed. The tests in beams were carried out under three different conditions of loads, with two distinct spans, in total of sixty four tests. For the purlins connected to roof system, the tests were in a \"suction box\", developed especially for this project. The purlins were connected to the roof system by the flange by using self-drilling screws, being carried out fifteen tests. The results of those tests are compared with the theoretical results, design specification provisions and results of some approximated procedures.
Maia, Wanderson Fernando. "Análise teórica e experimental de barras em dupla cantoneira de aço formada a frio submetidas à compressão". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-10102012-083428/.
Pełny tekst źródłaDouble-angle members with batten plates consist of two identical angles set up in parallel, spaced apart, and connected to each other by batten plates at specified points along the length. The system presented herein is widely used, especially in light truss structures; however, there are no standard design procedures specific for the design of this structural component. Studying the behavior of double angle members is interesting, because in this case, besides the critical modes of the single angle, they also show critical modes, due to the presence of the batten plates that sometimes interfere with the behavior of the system. This work presents a numerical and experimental study of members under concentric and eccentric axial compression. The number of batten plates is changed to study the influence on the nominal axial strength. The use of batten plates significantly increases the strength of the system, especially for members under eccentric compression. The buckling modes observed were flexural-torsional, flexural and combination of the modes. Initially, two design hypotheses are compared to the results obtained: (i) non-composite action (no interaction between angles), with only local, flexural, and flexural-torsional buckling considered; (ii) composite action (full interaction between angles), and only considering local and minor-axis flexural buckling of the pair of angles. The two design hypotheses ignore load eccentricity. The hypotheses are based upon recommendations in ABNT NBR 14762:2010. In general, numerical and experimental results for angles connected by bolted batten plates fall in between the design curves defined by methods (i) and (ii). With the results obtained in numerical and experimental analysis, procedures are recommended for the design of this structural component.
Neto, Alomir Hélio Fávero. "Terças em perfis de aço formados a frio com continuidade nos apoios: ênfase ao estudo das ligações de alma parafusadas com transpasse ou luva". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-07012014-142940/.
Pełny tekst źródłaCold-formed steel purlins are widely used in roofs and wall systems. The continuity of long runs of cold-formed steel purlins is guaranteed by sleeve and overlap bolted connections, which allows a better load distribution and material savings. The structural behavior of these connections is highly dependent on their geometric configuration and load level. The strength and stiffness of these connections were determined through a series of nine experiments, numerical and analytical analysis. Results have shown that distortional buckling has a major contribution on the stability analysis of the cold-formed steel purlin. To safely determine the flexural strength of the purlin, one must consider unrestrained bending stress distribution and distortional buckling. The connection type influences the rigidity of the purlin thus the vertical displacement. Purlins with overlapped connections are stiffer than physically continuous ones, although purlins with sleeved connections are not. The bearing deformation at the connection region is responsible for a reduction in the system stiffness. To account for the change in stiffness and determine the vertical displacement, an expression for the bearing stiffness and a beam model are proposed. The results of this model show good agreement with experimental data. The general conclusion of this research is: overlapped bolted connections enhance the structural response of the purlins when compared to physically continuous ones. The same does not hold true for purlins with sleeved connections.
Junior, Luiz Carlos Marcos Vieira. "Análise numérica do comportamento estrutural e da resistência de terças de aço restringidas pelas telhas". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-01102007-091559/.
Pełny tekst źródłaThe structural behavior of purlin-sheeting system is complex and the complete analysis should consider the physical and geometrical nonlinearity, as well as the influence of the purlin-sheeting contact and connection. The brazilian code NBR 14762:2001 provides a design procedure to consider the interaction between a purlin or girt connected to the sheeting (factor R method). In Brazil purlins and girts are typically designed as isolated beams, without consideration for this purlin-sheeting combination. Numerical models proposed in the literature were analyzed and a finite element model (FEM) was developed considering nonlinearities and the contact between purlin and sheeting. The model was validated through experimental results and then implemented in a parametrical analysis. Expressions were generated using the parametrical results to relate the loading (wind uplift) to the displacements. The direct strength method (DSM) was analyzed to the designed of purlins restrained by sheeting. The finite strip method (FSM) was used for elastic buckling determination. The restraint applied to the sheeting was modeled using an elastic foundation on the flange connected to the sheeting. Two stress distributions were considered: (i) bending stresses and (ii) bending and warping stresses. In both cases the nominal flexural strength presented considerable differences compared to the factor R design method, reflecting the necessity of a specific study to evaluate the viability of the DSM approach for purlin design.
Chodraui, Gustavo Monteiro de Barros. "Flambagem por distorção da seção transversal em perfis de aço formados a frio submetidos à compressão centrada e à flexão"". Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-18072003-124917/.
Pełny tekst źródłaCold-formed steel members present, in many cases, an elevated width/thickness ratio (thin-walled members), which probably lead up to the local buckling, which is characterized by a plate buckling, and also may lead up to another buckling mode, called distortional buckling, not considered on the design of hot-rolled members, but which may result critical in cold-formed members, specially in the ones with edge stiffeners and made with high strength steel. Such phenomena is characterized by the instability of the group formed by the compression flange and its stiffener, changing the initial shape of the cross section. Nowadays, codes present procedures to evaluate members resistance also due to distortional buckling, as the simplified method in the Australian code, AS/NZS 4600:1996, proposed by HANCOCK, which was adopted by the new Brazilian code, NBR 14762:2001, the Direct Strenght Method, recently proposed as an AISI (American Iron and Steel Institute) Draft, and the GBT (Generalilzed Beam Theory).This work talks about procedures proposed to evaluate distortional buckling in members under compression and bending, comparing results obtained by the method showed in the brazilian code, by numerical Finite Strip Method elastic analisys - FSM, and by Finite Element Method analisys FEM, on members with and without initial imperfections. It is also done an explanation related to other international procedures to evaluate the phenomena.
Almeida, Saulo José de Castro. "Análise numérica de perfis de aço formados a frio comprimidos considerando imperfeições geométricas iniciais". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-03122007-093434/.
Pełny tekst źródłaThe work presents a numerical analysis on cold-formed steel members compressed between pinned ends. One is about an inquiry carried through in finite elements in which it was studied the influence of initial geometric imperfections, existing in plain channels and lipped channels, under the aspects of its form, magnitude and signal. The geometric imperfection is adopted on the forms of the local, global and distortional buckling modes, observing the susceptibility to such modes for each type of section. Each imperfection is evaluated on the isolated way and after that of associated way. Referring aspects to the strategy of modeling adopted in the construction of the numerical models are presented, as well as aspects of interest with regard to the developed nonlinear analyses. For ends of attainment of the ultimate load, it is examined the possibility to use isolated buckling modes to represent the geometric imperfections, as long as the amplitude it is adjusted. The cases that had applied coupled imperfection to represent the geometric imperfection detach the paper of the signal of the imperfection of the global type with regard to its association to the imperfections of the types local and distortional for lipped channels and, to the one of the local type for plain channels.
Bolandim, Emerson Alexandro. "Análise de confiabilidade em ligações parafusadas em chapas finas e perfis de aço formados a frio". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-27062011-140302/.
Pełny tekst źródłaThis work presents an investigation of analytical models for predicting the tensile strength to bolted connections in thin sheets and cold-formed steel members, according to four design specifications (ABNT NBR 14762:2010, ANSI AISI S100:2007-S, AS/NZS 4600:2005 and Eurocode 3 Parte1.3:2010). The study involved 404 experimental results of bolted connections, as follows: 232 connections in thin sheets, 104 connections in angles and 68 connections in channels, in which various geometric configurations were analyzed. A total of 1616 strength analysis were performed so that statistics of the random variable model error could be constructed. Thus, the model error analysis consists of plotting the probability of error model, then for the adherence tests could then be applied satisfactorily validating theoretical functions of probability distribution for the statistical representation of random variable. A regression was used in bolted connections to describe the variation of the model error with the thickness of the sheet and to describe the model uncertainty. The analysis showed that the models can predict Brazilians and Americans, on average, net section fracture more efficiently than the other specifications, for use of coefficient of reduction of net area, and also note that all models showed a great variability of results around the mean, which makes the reliability of the models is affected. The reliability analysis used to assess the safety level of design specifications, included the model error and other random parameters such as tensile strength of steel, dead (D) and live (L) loads, totaling 7092 analysis on bolted connections, revealing that the contribution the random variable model error in the security of these connections is considerable, especially for load ratios (Ln/Dn) between 0.50 and 2.50. It should also be noted that the design specifications were evaluated according to sufficient and uniform reliability criteria showing that uniformity is achieved more easily for the four specifications, for load ratios (Ln/Dn) higher than 2.0, and that the sufficiency of security, most of the analysis, is not achieved, especially for the failure modes of bearing of the hole, in which the reliability index for the connections are located around 2.0 to 2.5, below the target value of 3.5 indicated by AISI and 3.8 indicated by EUROCODE. Furthermore, when dealing with the net section fracture, the models Brazilian, American and Australian also did not reach desirable levels of security, however, provided failure probabilities well below those obtained for the failure modes of bearing. Finally, sensitivity analysis revealed that the parameters x/L and d/g, present in the analytical models for predicting the net section fracture, the specification for Brazilian and U.S., do not affect the structural safety of the connections.
Baságlia, Cilmar Donizeti. "Sobre o comportamento estrutural de terças de aço considerando a interação com as telhas". Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-06042016-104944/.
Pełny tekst źródłaRecent years have seen a significant reduction in the use of heavy sheeting such as fiber cement roof sheets in industrial buildings, and an increasing preference for lighter sheeting that allows for greater rationalization of the construction, such as metallic sheeting (zinc-coated and aluminum). Thus, fixing by means of hooks was naturally replaced by screws, allowing for high structural efficiency of the purlin-sheeting combination, and purlins, which heretofore had been treated as independent structural elements, began to be designed based on their combined behavior with sheeting. This paper discusses the findings of a comprehensive on the structural behaviour of steel purlins under wind uplift considering the purlin-sheeting combination, with emphasis on lateral distortional. To this end, an analysis is made of the theoretical models available in the literature and in standard procedures, and systems representative of roofs are analyzed numerically via the finite elements method (FEM), including the effects of physical and geometrical nonlinearity. Based on these numerical models, which are validated by the experimental results of tests conducted at School of Engineering of São Carlos - University of São Paulo, an evaluation is made of the influence of the purlin\'s flexural stiffness, the sheeting-purlin connection, the type of purlin section (channel and Z-sections), and the number of rows of bridging (bracing). In this context, it was concluded that sheeting, provided it is properly fixed to the purlins, contributes toward lateral stability, imposing failure modes that differ considerably from the classic mechanisms of the theory of elastic stability.
Gilio, Fernando Henrique Santana. "Terças de aço formadas a frio com continuidade nos apoios por meio de luvas". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-06042016-111403/.
Pełny tekst źródłaThere are basically two systems employed to promote the continuity of multi-span purlins: overlap and sleeve. From the point of view of transport and assemblage, the sleeve system is advantageous in relation to the overlap system since it leads to shorter length bars. However, the use of sleeves has not been hardly explored mainly due to lack of knowledge about the system structural behavior and, therefore, the absence of design recommendations provided by standards and technical manuals. This study analyzed the stiffness and strength of continuous Z-section purlins with sleeved bolted connection. In order to develop the study a series of fifteen prototype were tested in bending; their cross-section height, thickness, sleeve length and span were varied. A viability analysis of the Direct Strength Method (DSM) for design of continuous sleeve purlins was conducted. In relation to stiffness, moment-rotation curves were calibrated experimentally and implemented in numerical models through rotational springs to simulate the nonlinear behavior of the connection. Afterwards, a moment-rotation expression based on the studied variables and a parametric analysis was proposed. This expression represents the connection stiffness and, when implemented in a simple spring-beam model, allows a more accurate prediction of the internal efforts and displacements in the purlin-sleeve system.
Silva, Julio Cesar Martins da. "Análise teórica-experimental de perfis de aço formados a frio devido à instabilidade por distorção na flexão". Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-03062016-135325/.
Pełny tekst źródłaThis work present a study theoretical-experimental about the distortional buckling of cold-formed steel members under bending. The distortional buckling is common for members with edge-stiffened sections and manufactured with steel of high strength. The theorical part present the analitic and numerical methods for stability analysis by distortional buckling. The experimental part included the study of cold-formed with sections channel altering flange width and thickness by proof in flexural members. Included too the numerical analysis by Direct Strength Method in Finite Strip Method on members with the same configurations of experimental investigation. Based on the experimental measurements, numerical analysis and in the theorical analysis of work, verified the procedures adopted in brazilian code NBR14762/2001 and compared with others distortional curve proposed for to design of cold-formed members under bending. Verified that the distortional buckling may control the design being the critical mode for the ultimate limit state.
Branquinho, Maria Ávila. "Sobre o comportamento estrutural e o dimensionamento de cantoneiras de aço formadas a frio submetidas à compressão e conectadas por uma aba". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-30032017-103451/.
Pełny tekst źródłaThe equal-leg angle is found hot-rolled or cold-formed. When hot-rolled, it usually has compact legs, that is, if subjected to compression it does not present local buckling and it does not present a global flexo-torsion buckling mode as dominant for the usual range of lengths. When cold-formed, these modes predominate, since the width-to-thickness ratio becomes high. The high slenderness of the legs, together with the peculiarities of its mechanical behavior, can lead to significant divergences between the axial strength (experimental) and the values from standard\'s procedures. The divergences are even greater when considering the angle in its most usual loading situation: under eccentric compression due to bolted or welded connection in one leg. In the present work the mechanical behavior of the cold-formed angles connected by the leg by two bolts was analyzed in order to propose a formulation based on the equivalent buckling length method, as well as, to define its buckling modes and the respective modal participation for different slenderness ranges. To validate this formulation, a reliability analysis was performed that resulted in reliability indexes (β) according to the design standards requirements.
Anapayan, Tharmarajah. "Flexural behaviour and design of hollow flange steel beams". Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/36210/1/Tharmarajah_Anapayan_Thesis.pdf.
Pełny tekst źródłaAbdel-Rahman, Nabil Mahmoud. "Cold-formed steel compression members with perforations". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ30065.pdf.
Pełny tekst źródłaN'emedi, Zsolt V. "Development of performance sections for cold-formed steel residential construction". Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-08222009-040502/.
Pełny tekst źródłaKyvelou, Pinelopi. "Structural behaviour of composite cold-formed steel systems". Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/50694.
Pełny tekst źródłaHuynh, Minh Toan. "Structural Behaviour of Cold-Formed Steel Screwed Connections". Thesis, The University of Sydney, 2020. https://hdl.handle.net/2123/22098.
Pełny tekst źródłaZhang, Jiahui, i 张佳慧. "Cold-formed steel built-up compression members with longitudinal stiffeners". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206457.
Pełny tekst źródłapublished_or_final_version
Civil Engineering
Doctoral
Doctor of Philosophy
Silva, Juliana Maria Mazzeti. "Terças de aço em perfis formados a frio com alma enrijecida: ênfase na força cortante e na interação momento fletor-força cortante". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-05062018-095440/.
Pełny tekst źródłaThe use of high strength steel in cold-formed purlins leads to a reduction in thickness and, as a consequence, the instability becomes more significant. In order to improve the structural efficiency of the sections, longitudinal stiffeners can be inserted into the web, increasing the strength in relation to local buckling. Although the use of sections with stiffened web is a common practice, the appropriate procedures for design are rarely discussed in scientific literature. The purpose of this work was to study the structural behavior of cold-formed steel purlins ZAE-sections, with 90º lips and two longitudinal stiffeners in the web. Therefore, theoretical and experimental analyses were performed, involving a set of purlins with stiffened web ZAE-sections and their equivalent plain web, the Z-sections with 90º lips. Although emphasis was given in shear and combined bending and shear, additional experimental tests were performed to evaluate the predominance of bending. Changes in critical elastic buckling stresses due to longitudinal stiffeners were evaluated and experimental and numerical data were used to predict the interation. Theoretical results indicated that longitudinal stiffeners of the ZAE-sections have little influence on distortional and global buckling. However, it has a great influence on local buckling, promoting a significant increase of the critical stresses in relation to the Z-sections. Experimental results showed that the ultimate strength of the Z-sections was higher than ZAE-sections, mainly due to the development of tension field action and the rotational restraint of the web conferred by the connection. The prototypes without distortion restraint presented premature failure, caused by rotation of the web in the region of the supports. Considering the distortion-constrained prototypes, the results satisfied the \"circular\" and \"trilinear\" interaction curves. It was concluded that design of purlins with stiffened web can be performed using the \"trilinear\" interaction expression and the distortional buckling moment capacity.
Padilla-Llano, David Alberto. "A Framework for Cyclic Simulation of Thin-Walled Cold-Formed Steel Members in Structural Systems". Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/52904.
Pełny tekst źródłaPh. D.
Leal, Davi Fagundes. "Sobre perfis de aço formados a frio compostos por dupla cantoneira com seção \"T\" submetidos à compressão". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-15072013-104844/.
Pełny tekst źródłaNowadays, among cold-formed steel members (PFF) commonly used in current structural systems, deserve to be highlighted those composed by two angles connected through intermediate fastener (stitch-fillers) forming a \"T\" section. Although its widespread use, little is known about its structural behavior, especially in what concerns instability modes. In this study, based on tools available on the ANSYS code, numerical finite element models were developed in order to investigate the structural behavior of these profiles under compression to contribute to future revisions of the ABNT NBR 14762:2010 specifications regarding PFF compounds. By using non-linear analysis, we investigated the influence of various factors in the structural response, namely, the loading introduction (compression-centric or eccentric), the boundary conditions, the global slenderness, the geometric imperfections, the angle thickness and the number stitch-fillers. The numerical results indicated that the compression resistance, obtained according to ABNT NBR 14762:2010, it is quite conservative, especially in cases of small global slenderness. Additionally, the stitch-fillers distribution proved its great influence both in the bearing capacity as in the determination of the instability modes. Finally, the study makes an introductory research on double angle profiles under high temperatures, in order to verify its performance under fire. The thermal analysis showed fire resistance results inferior to the minimum specified by ABNT NBR 14432:2001, indicating the need of using fire protection and further studies this subject.
Zhang, Hanwen. "Connections in cold-formed steel modular building structure systems". Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8181/.
Pełny tekst źródłaAfshan, Sheida. "Structural behaviour of cold-formed stainless steel tubular members". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/23660.
Pełny tekst źródłaGanesan, Karthik. "Resistance Factor for Cold-Formed Steel Compression Members". Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/33694.
Pełny tekst źródłaMaster of Science