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.

Thesis (M. Dev.) -- University of Limpopo, 2002 / Refer to document

Terrorism has become a serious threat in the world, with bomb attacks carried out both inside and outside buildings. There are already many unreinforced masonry buildings in existence, and some of them are historical buildings. However, they do not perform well under blast loading. Aiming on protecting masonry buildings, retrofitting techniques were developed. Some experimental work on studying the effect of retrofitted URM walls has been done in recent years; however, these tests usually cost a significant amount of time and funds. Because of this, numerical simulation has become a good alternative, and can be used to study the behaviour of masonry structures, and predict the outcomes of experimental tests. This project was carried out to find efficient retrofitting technique under blast loading by developing numerical material models. It was based on experimental research of strengthening URM walls by using retrofitting technologies under out-of-plane loading at the University of Adelaide. The numerical models can be applied to study large-scaled structures under static loading, and the research work is then extended to the field of blast loading. Aiming on deriving efficient material models, homogenization technology was introduced to this research. Fifty cases of numerical analysis on masonry basic cell were conducted to derive equivalent orthotropic material properties. To study the increasing capability in strength and ductility of retrofitted URM walls, pull-tests were simulated using interface element model to investigate the bond-slip relationship of FRP plates bonded to masonry blocks. The interface element model was then used to simulate performance of retrofitted URM walls under static loads. The accuracy of the numerical results was verified by comparing with the experimental results from previous tests at the University of Adelaide by Griffith et al. (2007) on unreinforced masonry walls and by Yang (2007) on FRP retrofitted masonry walls. To study the de-bonding behaviours of retrofits bonded to masonry, and find appropriate solution to protect certain masonry walls against blast loading, various retrofitting technologies were examined. The simulation covers explosive impacts of a wide range of impulses. Based on this work, pressure-impulse diagrams for different types of retrofitted URM walls were developed as a design guideline for estimating the blast effect on retrofitted masonry walls. The outcomes of this research will contribute to the development of numerical simulation on modelling retrofitted URM walls, improving the technique for explosion-resistant of masonry buildings, and providing a type of guideline for blast-resistant design. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1349719 / Thesis (M.Eng.Sc.) - University of Adelaide, School of Civil, Environmental and Mining Engineering, 2009

Terrorism has become a serious threat in the world, with bomb attacks carried out both inside and outside buildings. There are already many unreinforced masonry buildings in existence, and some of them are historical buildings. However, they do not perform well under blast loading. Aiming on protecting masonry buildings, retrofitting techniques were developed. Some experimental work on studying the effect of retrofitted URM walls has been done in recent years; however, these tests usually cost a significant amount of time and funds. Because of this, numerical simulation has become a good alternative, and can be used to study the behaviour of masonry structures, and predict the outcomes of experimental tests. This project was carried out to find efficient retrofitting technique under blast loading by developing numerical material models. It was based on experimental research of strengthening URM walls by using retrofitting technologies under out-of-plane loading at the University of Adelaide. The numerical models can be applied to study large-scaled structures under static loading, and the research work is then extended to the field of blast loading. Aiming on deriving efficient material models, homogenization technology was introduced to this research. Fifty cases of numerical analysis on masonry basic cell were conducted to derive equivalent orthotropic material properties. To study the increasing capability in strength and ductility of retrofitted URM walls, pull-tests were simulated using interface element model to investigate the bond-slip relationship of FRP plates bonded to masonry blocks. The interface element model was then used to simulate performance of retrofitted URM walls under static loads. The accuracy of the numerical results was verified by comparing with the experimental results from previous tests at the University of Adelaide by Griffith et al. (2007) on unreinforced masonry walls and by Yang (2007) on FRP retrofitted masonry walls. To study the de-bonding behaviours of retrofits bonded to masonry, and find appropriate solution to protect certain masonry walls against blast loading, various retrofitting technologies were examined. The simulation covers explosive impacts of a wide range of impulses. Based on this work, pressure-impulse diagrams for different types of retrofitted URM walls were developed as a design guideline for estimating the blast effect on retrofitted masonry walls. The outcomes of this research will contribute to the development of numerical simulation on modelling retrofitted URM walls, improving the technique for explosion-resistant of masonry buildings, and providing a type of guideline for blast-resistant design. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1349719 / Thesis (M.Eng.Sc.) - University of Adelaide, School of Civil, Environmental and Mining Engineering, 2009

Terrorism has become a serious threat in the world, with bomb attacks carried out both inside and outside buildings. There are already many unreinforced masonry buildings in existence, and some of them are historical buildings. However, they do not perform well under blast loading. Aiming on protecting masonry buildings, retrofitting techniques were developed. Some experimental work on studying the effect of retrofitted URM walls has been done in recent years; however, these tests usually cost a significant amount of time and funds. Because of this, numerical simulation has become a good alternative, and can be used to study the behaviour of masonry structures, and predict the outcomes of experimental tests. This project was carried out to find efficient retrofitting technique under blast loading by developing numerical material models. It was based on experimental research of strengthening URM walls by using retrofitting technologies under out-of-plane loading at the University of Adelaide. The numerical models can be applied to study large-scaled structures under static loading, and the research work is then extended to the field of blast loading. Aiming on deriving efficient material models, homogenization technology was introduced to this research. Fifty cases of numerical analysis on masonry basic cell were conducted to derive equivalent orthotropic material properties. To study the increasing capability in strength and ductility of retrofitted URM walls, pull-tests were simulated using interface element model to investigate the bond-slip relationship of FRP plates bonded to masonry blocks. The interface element model was then used to simulate performance of retrofitted URM walls under static loads. The accuracy of the numerical results was verified by comparing with the experimental results from previous tests at the University of Adelaide by Griffith et al. (2007) on unreinforced masonry walls and by Yang (2007) on FRP retrofitted masonry walls. To study the de-bonding behaviours of retrofits bonded to masonry, and find appropriate solution to protect certain masonry walls against blast loading, various retrofitting technologies were examined. The simulation covers explosive impacts of a wide range of impulses. Based on this work, pressure-impulse diagrams for different types of retrofitted URM walls were developed as a design guideline for estimating the blast effect on retrofitted masonry walls. The outcomes of this research will contribute to the development of numerical simulation on modelling retrofitted URM walls, improving the technique for explosion-resistant of masonry buildings, and providing a type of guideline for blast-resistant design. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1349719 / Thesis (M.Eng.Sc.) - University of Adelaide, School of Civil, Environmental and Mining Engineering, 2009

Cette recherche s'intéresse aux matériaux de construction et aux architectes. Elle explore les circuits le long desquels circulent les matériaux et étudie les dispositifs dont ils sont munis pour rendre cette circulation possible. Elle se penche sur les rôles que jouent et sur ceux que pourraient jouer les concepteurs au sein de ces circuits et en regard de ces dispositifs.<p>Ce travail s'inscrit dans le cadre d'une réflexion sur les pratiques de l'aménagement de l'espace bâti. Au cours de son trajet entre son site de production et celui de sa mise en œuvre (c'est-à-dire le chantier de construction) – et même au-delà, lorsqu'une transformation libère des éléments constructifs – un matériau passe par de nombreuses étapes. Parmi toutes celles-ci, le passage par le moment de la conception est un élément central de cette recherche (même si d'autres étapes seront également explorées au fil de pages de ce travail). Quels rôles les concepteurs jouent-ils au sein de ces vastes assemblages d'acteurs et de dispositifs qui se déploient le long des trajectoires des matériaux de construction ? Comment les concepteurs sont-ils affectés par ces assemblages et comment peuvent-ils les affecter en retour ?<p>Répondre à ces questions engage une exploration des principales trajectoires des matériaux de construction et un examen attentif des dispositifs dont ils sont munis au fil de ce processus. C'est ce à quoi s'attache la première partie de cette recherche, dont la portée est plutôt descriptive. Mais elle ne s'arrête pas à ce stade. Elle comporte également une seconde partie, plus prospective et critique. Cette recherche propose en effet d'explorer certaines pistes de reconfiguration au sein de ces assemblages. Elle examine plusieurs questions touchant aux limites des circuits de l'économie matérielle : par quelles modifications faudrait-il en passer pour que des matériaux actuellement exclus des circuits les plus courants de l'économie matérielle puissent malgré tout y circuler ? D'autres arrière-plans axiologiques pourraient-ils être mis en jeu dans les circuits de l'économie matérielle ?<p>La présente recherche repose sur l'hypothèse que les concepteurs peuvent effectivement contribuer à la transformation progressive des circuits de l'économie matérielle. Ils ont vraisemblablement un rôle à jouer dans la possibilité d'ouvrir ces circuits à de nouveaux matériaux, et de contribuer ainsi à établir des pratiques plus à même de répondre aux enjeux écologiques et politiques auxquels sont confrontés notre planète et ses habitants. Bien sûr, les concepteurs n'ont pas l'exclusivité de tels changements. D'autres acteurs peuvent, et même doivent, participer à de tels efforts. Ce sont pourtant principalement les concepteurs qui retiendront l'attention de cette recherche. Il s'agit dans ce cadre d'explorer les conditions d'un tel changement, et ce tant d'un point de vue méthodologique que d'un point de vue pratique.<p>/<p>This research investigates the relation between construction materials and architects. It examines the circuits along which the materials circulates and it studies the devices that are embedded in the materials in order to render this circulation feasible. It looks into the roles that are played, and those that could be played, by the designers within these circuits and in regard with these devices.<p>This work is part of a reflection on the practices of designing and constructing the built environment. During its journey between its production site and that of its implementation (i.e. the construction site) – and even beyond, when a transformation frees again constructive elements – a construction material travels through many steps. Among all these, the passage through the design process is a key element. What role do the designers perform within these networks of actors and devices? How are they affected by these assemblages and how can they affect them in return?<p>Answering these questions undertakes an exploration of the main trajectories of construction materials and of the devices that are embedded throughout these processes. This is the topic of the first part of the research. At this point, the scope is mainly descriptive. But the research goes further: it also involves a more critical and prospective dimension. It proposes indeed to discuss several possible reconfigurations within these assemblages. What would be necessary in order to include new materials that are currently excluded from the main circuits of material economy? Could other axiological backgrounds be represented within these circuits?<p>This research is based on the assumption that designers can effectively contribute to the gradual transformation of the circuits of material economy. They can probably help alternative materials to circulate in more standard circuits, and thus help to establish new practices that are more likely to respond to environmental and social issues. Of course, the designers do not have a monopoly on such changes. Other actors may, and even must, participate in such efforts. Yet, the main focus of this research is the designer. It explores the conditions of such a change, both from a methodological and practical perspective. / Doctorat en Art de bâtir et urbanisme / info:eu-repo/semantics/nonPublished