A finite element modeling and geometrically nonlinear static analysis of the top portion of a glued-laminated timber dome is presented. The modeling assumptions and analysis procedures are applied to a dome model whose geometry is based on an existing glulam timber dome of 133 ft. span and 18 ft. rise above the tension ring. This dome consists of triangulated network of curved southern pine glulam members connected by steel hubs. The dome is covered with a tongue-and· groove wood decking. The role of decking towards the stability of the overall structure is studied. The lateral resistance of the nail fasteners connecting the beams and the purlins to the decking is considered . The stabilizing effect of the decking is shown to be mathematically analogous to that acting on the beams along the line of the deck attachment. The axial pull, in this study is modeled by truss members. Three distinct analyses are performed for rigid and flexible joints: a linear analysis to check design adequacy of the members, a linearized eigenvalue buckling prediction analysis to estimate the buckling load, and finally an incremental, iterative, geometrically nonlinear analysis to trace the complete response of the structure up to failure. Analyses are done for the structure with and without the decking on top of the beams and purlins to assess the role of decking on the overall stability of the structure. It is shown that decking plays a considerable role in the load-carrying behavior of the whole structure. A discussion of the results is presented and recommendations for future extensions are included. / Master of Engineering

Student Number : 0003370N - MSc dissertation - School of Civil and Environmental Engineering - Faculty of Engineering / This dissertation investigates the different design and construction considerations involved when building a masonry dome. A detailed shape investigation was undertaken in order to summarize the best shaped dome structures. General recommendations are given for the shapes that produce the least tension and the most useable space. The effects of openings, temperature loading and wind loading were considered and a finite element analysis of the final structure was undertaken. It was found that regions of high tension exist around openings, especially under temperature loading, and materials suitable to resisting this tension were investigated (fibre plaster, chicken wire mesh and wire wrapping around openings). The final structure was built using an inflatable formwork. The construction procedure was well documented and a study of alternative methods of construction is presented. This dissertation shows that a durable, architecturally and structurally efficient low-cost masonry dome can be built if proper attention is given to minimizing and resisting tension within the structure.

No description available.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 59-61). Also available via the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2008. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file and four media files (media file 1.pdf, media file 2.pdf, media file 3.pdf, and media file 4.pdf) Title from title screen of research.pdf file (viewed on August 25, 2008) Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [129]-138).

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 160-165). Also available via the Internet.

Disseratation--Hamburg.

The Thor-Odin gneiss dome is one of several structural culminations along the eastern margin of the Shuswap terrain. The gneiss domes have previously been ascribed both to diapiric uprise of granitic gneisses and to interference of late-stage buckle folds. The ages of rocks in the gneiss domes have also been the subject of controversy. Age estimates range from Archean to Mesozoic. This study provides the basis for a detailed model for a new interpretation of the structural evolution of the Thor-Odin gneiss dome. Prior to doming, this area was characterized by the formation of large-scale nappe structures and imbrication of Archean basement rocks with the cover rock sequence. The first period of deformation (Phase One) consisted of large-scale infolding of the cover rock sequence into the basement rocks. The Pingston fold in the core of the dome is a product of this event. The second period of deformation (Phase Two) was marked by the forcing of wedges of basement into the cores of northerly-moving nappes. The third period of deformation (Phase Three) was co-axial with Phase Two and consisted of imbrication and refolding of the upper levels of the stack of Phase Two nappes. Strain analysis based on fold shape, distorted lineation patterns and elliptical strain markers demonstrate that finite strains are highest in the imbricated zone between the Basement Cored Nappe Domain and the Cover Rock Domain. Flattening strains are anomalously low in the Autochthonous Core Gneiss Domain. Analysis of Phase Two fold axes distorted into flattened small circles by Phase Three folds shows that Phase Three strain magnitude √(λ₂/ λ₁) varies from 0.81 to 0.49. Rb-Sr whole rock geochronometry has revealed evidence for three Precambrian events within the basement gneisses. Unmigmatized metasedi-mentary basement gneisses form a six-point errorchron with an age of 2.73±0.20 Ga. Granitic gneisses previously dated at 1.96 Ga by the U-Pb zircon technique, give reset ages for gneiss/vein whole rock suites with ages in the range 750 to 860 Ma. Common lead systematics of stratabound sulfide deposits in the cover rock sequence suggest that the cover rocks are Cambrian in age, in agreement with earlier lithological correlations. The lead isotope ratios suggest the deposits were ultimately derived from an approximately 2.0 Ga basement terrain. The outcropping gneissic basement rocks of the Shuswap are dominantly granitic gneisses which give 2.0 to 2.2 Ga Rb-Sr whole rock dates.; Ductile deformation in the terrain appears to have ended by 150 Ma, as this corresponds to the ages of several post-tectonic intrusions which crosscut Phase Three folds and impose a contact metamorphic overprint on the regional metamorphic pattern. The Nelson Batholith is a post-tectonic batholith which intrudes both the Shuswap terrain and the Kootenay Arc to the east. Two sample suites were collected from the different batho-lithic phases and analyzed by Rb-Sr whole rock methods with the following results: Suite I - Porphyritic monzonite with alkali feldspar megacrysts from the West Arm of Kootenay Lake give a seven-point isochron with an age of 158 ± 16 Ma and an initial ratio of 0.7069 ± 0.0001. Suite I has a Rb-Sr feldspar, date of 153 ± 26 Ma, a K-Ar hornblende date of 143 ± 5 Ma, and a K-Ar biotite date of 60 ± 2 Ma. It seems likely that the K-Ar dates have been disturbed by thermal events subsequent to emplacement of the batholith. Suite II- Medium grained granodiorite from the southern tail of the Nelson Batholith gives a nine-point whole rock isochron with an age of 162 ± 6 with an initial ratio of 0.7065 ± 0.0001. Taken together, these data provide significant new information on the nature and timing of the events that formed the metamorphic core zone of the southern Canadian Cordillera. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

In order to predict the ultimate load capacity and failure modes of a glued-laminated timer dome, two dome models are analyzed by two finite element methods. I-DEAS is utilized to generate shell elements and to compute nodal forces for the dome model. Wind load requirements are studied, and the effect of wind loads is investigated. At first, linear and nonlinear analyses of a space frame are carried out for four load combinations of dead load and snow load. The results are applied as a basis for the modeling of flexible joints and bracings. Then, the 3-D, 3-noded, curved, isoparametric beam element in the first model is replaced by a 3D, 2-noded, straight beam element for the second model. Purlins consist of truss elements. Flexible joints are modeled by adding connector elements to the ends of each beam. A bracing of truss element is applied to simulate the contribution of the decking. The dome is analyzed for two load conditions. The buckling pressures, buckling modes and the material behavior prior to buckling are examined. Finally, conclusions are made and several topics are recommended for future studies. / Master of Science