Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 256-262). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 429-435). Available also in a digital version from Dissertation Abstracts.

A confined masonry (CM) wall consists of a masonry wall panel surrounded by reinforced concrete (RC) members on its perimeters. Low-rise CM structures are widely used in earthquake-risked (EQ-risked) rural or suburban areas all over the world. Most of these structures fail in shear pattern under lateral EQ loads, and some of them collapse under a severe or even a moderate EQ due to inappropriate design. On the other hand, buildings constructed of RC frames have much better performance in resisting EQs, since their RC members have larger dimensions and heavier reinforcing ratios than those in CM structures. Nonetheless, RC-frame buildings are normally too expensive for most inhabitants in less developed regions. In this study, as an improvement to the conventional CM buildings for EQ resistance and for the sake of post-EQ restoration, a hybrid masonry – RC (HMR) structure, whose working mechanism is different from that of a conventional CM structure, is proposed. The RC members (i.e. “tie beams” and “tie columns”), which function only as confinement in a CM building, will resist most of gravity load and part of lateral EQ load in an HMR structure, while the wall panels will take most of lateral EQ load and part of gravity load. This is achievable by slightly increasing the sizes and reinforcing ratios of RC members in HMR structures. Such buildings will not collapse in the absence of masonry wall panels because the gravity load bearing system is still intact. On the other hand, as the wall panels in the proposed HMR structure will absorb most of the energy induced by lateral EQ load, severe damages will be controlled within the wall panel region, so that only the wall panels need to be replaced instead of rebuilding the whole structure after the EQ event. To investigate the mechanical behaviours of masonry assemblages to be used in HMR structures, a series of experimental tests were conducted. Having established the relevant material properties for HMR structures, finite element (FE) simulation was performed to verify its work mechanism. Prior to applying the FE simulation to HMR structures, the FE technique was first applied to simulate the behaviours of two concrete-brick masonry panels under diagonal compression loading and a CM wall under cyclic lateral loading. The results show a good correlation between the experimental results and the simulated ones. This has validated the feasibility of using the FE software to study the proposed HMR structure. The theoretical simulation results show that in a properly designed HMR wall, depending on the masonry reinforcing details and the boundary conditions of simulated load cases, about 70% of the gravity load imposed on the RC beam will be transferred to the RC columns and more than 80% of the seismic energy (in terms of strain energy) will be absorbed by the masonry panel. Therefore, it is obvious that the proposed HMR structure is very feasible to replace the conventional CM structure in resisting EQ attacks with no risk of collapse. / published_or_final_version / Civil Engineering / Master / Master of Philosophy

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Reinforced concrete buildings may be vulnerable to progressive collapse due to a lack of continuous reinforcement. Progressive collapse is an extreme form of collapse that is disproportionate to the originating cause. Such collapses cause not only significant damage to buildings, but also greater loss of life and injuries. Carbon fiber reinforced polymer (CFRP) may be used to retrofit existing reinforced concrete beams and provide the missing continuity needed to resist progressive collapse. This research focuses on retrofitting the beams in a reinforced concrete building to provide sufficient continuity to reach catenary action. The catenary action may allow the beam to carry vertical loads at large displacements if a supporting column were removed. The CFRP can provide continuity through the negative moment reinforcement or through the positive moment reinforcement. The research was broken into three major components. Anchorage tests form the design basis of the CFRP retrofit and ensure that the capacity of the retrofit can be accurately predicted. Continuity tests determine if the CFRP retrofit is capable of providing continuity and if the retrofit will allow the beam to reach catenary action and sustain a load representing resistance to progressive collapse. The analysis model forms a set of equations for catenary action so the results can be applied to reinforced concrete beams in general. Forty anchorage tests, eight continuity tests, and one analysis model were constructed and evaluated. The anchorage tests found that carbon fiber anchors enabled improved utilization of the tensile capacity of a CFRP sheet and improved the efficiency of material usage in CFRP retrofits. The continuity tests found that beams without continuous reinforcement can reach catenary action (depending on design details) and a CFRP retrofit, if designed correctly (placed in locations that do not cause rebar fracture before catenary), may be able to reduce vulnerability to progressive collapse. The analysis model was able to accurately predict the load-deflection behavior of a reinforced concrete beam in catenary action. The overall conclusion is that a CFRP retrofit can reduce vulnerability to progressive collapse in reinforced concrete buildings. / text

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No description available.

Šiame bakalauro baigiamajame darbe suprojektuotas trijų aukštų kareivinių pastatas su sporto sale ir rūsiu. Pastatą numatyta statyti Šiaulių rajone Mumaičių kaime esančioje karinio dalinio teritorijoje. Pirmajame, antrajame ir trečiajame aukšte išdėstomos patalpos skirtos vienai kuopai. Rūsyje įrengiamos patalpos ginklų saugykloms, ginklų valymui ir kuopų daiktų saugyklos. Prieš pastatą įrengiama rikiuotės aikštė, šaligatviai pėstiesiems, numatyta galimybė privažiuoti prie pastato transportui, likusi sklypo dalis apželdinama.Projektą sudaro architektūrinė, konstrukcinė, technologinė-ekonominė dalys, bei brėžiniai.Pirmojoje – architektūrinėje – dalyje aprašomas sklypas, pastato charakteristika, jo inžineriniai tinklai, bei konstrukciniai ir apdailos sprendimai. Brėžiniuose pateikiami sklypo ir pastato planai, fasadai, pjūvis bei mazgai. Konstrukcinėje dalyje projektuojama plieninė sija S1 ir gelžbetoninė stendinio formavimo perdangos plokštė PK-53-14-S600. Pridedami šių konstrukcijų darbo brėžiniai. Technologinėje-ekonominėje dalyje pateikiami kai kurių darbų technologijos, technologinė kortelė, darbų kiekių žiniaraštis bei pagal tuos kiekius parengta lokalinė sąmata, kiti žiniaraščiai. Grafinėje dalyje pateikiamas statybvietės planas, kuriame numatytas eismas statybų teritorijoje, medžiagų aikštelės, darbuotojų buitinės patalpos, parinktas kranas. / This Bachelor’s work of designing three-story barracks building with a gym and a basement. The building is planned to construct Siauliai district Mumaičiai village in the territory of the military unit. The first, second and third floor space arranged for one company. Installed in the basement room weapon storage, gun cleaning and companies storage. Before building equipped formation Square, sidewalks for pedestrians, the possibility of approaching the building of transport, the remaining part of the plot plante. The project consists of architectural, structural, technological-economic parts and drawings. The first - the architecture - describes the plot, building characteristics, the engineering systems, and the construction and finishing solutions. The drawings presented in the site and building plans, elevations, sections and assemblies.The constructive part of the design of steel beam S1 and reinforced concrete floor slab forming poster PK-53-14-S600. These structures are attached drawings.Technological-economic section describes some of the work, technological card, work records and quantities of quantities prepared by local estimate, the other sheets. The graphic layout of the building, which includes traffic building sites, material sites, employee household premises, selected The project is carried out in accordance with the Ministry of construction law, building regulations (STR), the rules and background material provided in the reference list.