Steel load-bearing structure of a museum will serve to exhibit the museum's exhibits and organizing exhibitions for the public. The structure is elliptical in shape with a length of 30 m in direction of the major axis and 22 m in the direction of the minor axis. Construction height is 9 m. There is located gallery structure in the inner part of the museum with access by an internal staircase. The main load-bearing elements of museum structure are designed from steel S235. The roof deck is made from Kingspan panels and cladding consists of laminated safety glass.

The analysis and design of bracing systems for complex frame geometries typically found in metal buildings can prove to be an arduous task given current methods. The American Institute of Steel Construction's Appendix 6 from the 2010 Specification for Structural Steel Buildings affords engineers a means for determining brace strength and stiffness requirements, but only for the most basic cases. Specifically, there are a number of aspects of metal building systems that place their designs outside the scope of AISC's Appendix 6 (Stability Bracing for Columns and Beams). Some of the aspects not considered by Appendix 6 include: the use of web-tapered members, the potential for unequally spaced or unequal stiffness bracing, combination of bracing types including panel and flange diagonal bracing, and the effects of continuity across brace points. In this research, an inelastic eigenvalue buckling procedure is developed for calculation of the ideal bracing stiffness demands in general framing systems. Additionally, the software provides a method of calculating the elastic lateral-torsional buckling load of members with generally stepped and tapered cross-sections, which satisfies an important need for rigorous design assessment. Extensive benchmarking to load-deflection simulations of geometrically imperfect systems is performed and recommendations are developed for determining the required design stiffness and strength of the bracing components based on the use of this type of computational tool.

In the last 35 years, several researchers have proposed, developed and tested different friction devices for seismic control of structures. Their research has demonstrated that such devices are simple, economical, practical, durable and very effective. However, research on passive friction dampers, except for few instances, has not been given appropriate attention lately. This has caused some of the results of old studies to become out-of-date, lose their validity in the context of today's design philosophies or to fall short on the expectations of this century's structural engineering. An analytical study on the behavior of friction devices and the effect they have on the structures into which they are incorporated has been undertaken to address the new design trends, codes, evaluation criteria and needs of today's society. The present study consists of around 7,000 structural analyses that are used to show the excellent seismic performance and economic advantages of Friction Damped Braced Frames. It serves, at the same time, to improve our understanding on their dynamic behavior. Finally, this thesis also sets the basis for future research on the application of this type of seismic energy dissipating systems.

Seismic provisions for steel buildings present limiting width-thickness and slenderness ratios for bracing members. Most of these limits were established based on experimental observations. The number of experimental studies is limited due to the costs associated with them. With the rapid increase in computing power / however, it is now possible to conduct finite element simulation of brace components using personal computers. A finite element study has been undertaken to evaluate the aforementioned limits for pin-ended pipe section steel braces. Fifty four tubular pipe brace models possessing different diameter-to-thickness ratios varying from 5 to 30 and slenderness ratios varying from 40 to 200 were analyzed. The effect of cyclic hardening modulus on the response of braces was explored. In all analysis, the models were subjected to reversed cyclic displacements up to ten times the yield displacement. Local buckling was traced during the loading history using a criterion based on local strains. Results are presented in terms of the ductility level attained by the member at the onset of local buckling. It is shown that local buckling of the section is influenced by the diameter-to-thickness and the slenderness ratios of the member. Moreover, the amount of hardening modulus was found to affect the local buckling response significantly. The need to include this material property into seismic provisions is demonstrated. Finally, the hysteretic energy dissipated by the member was quantified for each displacement excursion.

Structures in high seismic risk areas may be susceptible to severe damage in a major earthquake. Structures designed to meet older code requirements may be at even greater risk. When these structures are evaluated with respect to current code criteria, it is observed that they lack of lateral strength and/or ductility. Since safety and economic considerations are major problems, these structures become viable candidates for retrofit and seismic strengthening. For the variety of structures and possible deficiencies that arise, several retrofitting techniques can be considered. Diagonal bracing system is one of the retrofitting techniques and it provides an excellent approach for strengthening and stiffening existing building for lateral forces. Also, another potential advantage of this system is the comparatively small increase in mass associated with the retrofitting scheme since this is a great problem for several retrofitting techniques. In this study, the use of steel bracing for the strengthening of low, intermediate, and relatively high rise reinforced concrete frames are investigated analytically. The ultimate lateral load capacities of the strengthened frames are determined by a load controlled push-over analysis. The post-tensioning effect of preloading is also investigated.

This research investigates the application of the AISC Direct Analysis Method for stability bracing design of columns, beams, beam-columns and frames. Emphasis is placed on out-of-plane flange bracing design in metal building frame systems. Potential improvements and extensions to the 2005 AISC Appendix 6 stability bracing provisions are studied and evaluated. The structural attributes considered include various general conditions encountered in practical metal building design: unequal brace spacing, unequal brace stiffness, nonprismatic member geometry, variable axial load or bending moment along the member length, cross-section double or single symmetry, combined bending and axial load, combined torsional and lateral bracing from girts/purlins with or without diagonal braces from these components to the inside flanges, load height, cross-section distortion, and non-rigid end boundary conditions. The research addresses both the simplification to basic bracing design rules as well as direct computation for more complex cases. The primary goal is improved assessment of the demands on flange bracing systems in metal building frames.

The use of knee braces prophylactically is still considered as an approach for injury mitigation for those in high-risk sporting activities, though their use is not fully supported. The purpose of this thesis was to examine biomechanical and neuromuscular effects of prophylactic brace wear following standardized repetitive exercise. Twelve participants participated and acted as their own control. The participants were required to participate in two sessions, one control session with no brace and one intervention session with the application of a off-the-shelf prophylactic knee brace. Pre-and post-exercise intervention single leg drop landings were recorded to examine the effects of an acute exercise stimulus on the neuromuscular and biomechanical effects of brace wear. Additionally, trials were collected at 30-minutes post-exercise to examine residual effects of the brace wear on landing kinematics and kinetics. Difference tests using analysis of variance (ANOVA) showed that there was a minimal effect of the prophylactic knee brace on biomechanical and neuromuscular variables following exercise as well as 30-minutes following knee brace removal. Further research may be required to identify if braces can be worn prophylactically to reduce the risk of injury during activity.

Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2016-09-21T13:53:20Z No. of bitstreams: 1 DissLFS.pdf: 15776549 bytes, checksum: d345f39604b7efb99df0f362ce8001a2 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-21T18:26:06Z (GMT) No. of bitstreams: 1 DissLFS.pdf: 15776549 bytes, checksum: d345f39604b7efb99df0f362ce8001a2 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-21T18:26:13Z (GMT) No. of bitstreams: 1 DissLFS.pdf: 15776549 bytes, checksum: d345f39604b7efb99df0f362ce8001a2 (MD5) / Made available in DSpace on 2016-09-21T18:26:19Z (GMT). No. of bitstreams: 1 DissLFS.pdf: 15776549 bytes, checksum: d345f39604b7efb99df0f362ce8001a2 (MD5) Previous issue date: 2015-08-25 / Não recebi financiamento / The use of precast concrete system in multi-storey buildings demand for structural solutions that enable its horizontal stability without implicating the architectural and economic aspects, its challenge is borne by the structural engineer, who often need to assign additional structures (substructures of bracing) that provide the rigidity necessary to ensure the overall stability of the assembly. This study aims to analyze and evaluate the technical and economic performance of bracing systems applied to buildings with multiple floors with precast concrete structure and can be justified by the current need to develop appropriate technically ways of choice in the constructive system. The development of this study is the analysis of global stability in multi-storey buildings with the application of bracing systems, evaluating the influence of the stiffness and the arrangement of these elements in the performance of the structure, and comparing the concrete consumption values of the structures formed by beams and columns (disregarding the slabs and the foundation), and also values of the efforts in the foundation. To develop this study we used the commercial software STRAP® as a support tool for calculations, where the results gotten by it, showed that the bracing substructures improved the behavior of the structures analyzed in the issue of global stability. Finally, they were provided the necessary subsidies for the proper choice of the wind bracing system to be employed on the structures analyzed in this work. / O emprego do sistema pré-moldado de concreto em edifícios de múltiplos pavimentos demanda por soluções estruturais que viabilizem a sua estabilidade horizontal, sem o comprometimento dos aspectos arquitetônicos e econômicos, tal desafio fica a cargo do engenheiro de estruturas, que muitas vezes necessita atribuir estruturas complementares (subestruturas de contraventamento) que ofereçam a rigidez necessária para garantir a estabilidade global do conjunto. Este estudo tem como objetivo analisar e avaliar o desempenho técnico e econômico dos sistemas de contraventamento aplicados em edifícios de múltiplos pavimentos com estrutura prémoldada de concreto e pode ser justificado pela necessidade atual de desenvolver maneiras tecnicamente adequadas de escolha do sistema construtivo. O desenvolvimento deste estudo consiste na análise da estabilidade global em edifícios de múltiplos pavimentos com a aplicação dos sistemas de contraventamento, avaliando a influência da rigidez e da disposição desses elementos no desempenho da estrutura, e comparando os valores dos consumos de concreto das estruturas formadas por vigas e pilares (desconsiderando as lajes e a fundação), e também os valores dos esforços na fundação. Para o desenvolvimento deste estudo foi utilizado o software comercial STRAP® como ferramenta de auxílio para os cálculos, onde os resultados obtidos através do mesmo, demonstraram que as subestruturas de contraventamento melhoraram o comportamento das estruturas analisadas na questão da estabilidade global. Por fim, foram fornecidos os subsídios necessários para a escolha adequada do sistema de contraventamento a ser empregados sobre as estruturas analisadas neste trabalho.

This master thesis concerns gait in patients with idiopathic scoliosis. Idiopathic scoliosis constitutes about 80 % of all scoliosis cases and its adolescent type is the most common form of spine deformity in the child population. The theoretical part outlines existing knowledge on this medical condition and its treatment, focusing on conservative therapy by corrective spinal orthoses. It further describes the physiological stereotype of gait and differences observed in patients with idiopathic scoliosis. It also discusses the effect exerted on bipedal locomotion by corrective spinal orthoses. The aim of the practical part is to examine whether there is a relationship between the severity of the main spinal curvature in subjects with scoliosis and the degree of asymmetry between their lower limbs for selected parameters of gait. Since this part concerns gait both without and with bracing, it can also analyse the impact of corrective spinal orthoses on the degree of the given asymmetries. The selected parameters of gait are ascertained by the method of dynamic plantography using a Zebris FDM- T System device. The research sample consists of 14 subjects (12 girls and 2 boys) between the age of 9 and 17 years with idiopathic scoliosis who receive conservative treatment including bracing. The results...

The aim of this thesis is design and assessment of the steel structure of the multi-storey administration center in Martin. Floor plan dimensions are in the shape of a square 40 x 40 m. Column spacing is 8mx8x. Building has 6 floors and total height is 22,2m. Floor and roof structure is made of steel-concrete composite slab . Part of the work is analyze two different versions. Version A has longitudinal rigidity due to truss bracing. Rigidity of Version B has is ensured by frame conections between beams and columns.Version A was selected as better solution. All parts, except truss braicing is made of rolled beams. The whole structure is made of steel S355.