265 research outputs found

    Visualizing Kitchener: Geocoding Historical Street Information

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    When studying and investigating the history of a property or neighbourhood, common resources often sought by researchers include air photos, fire insurance plans and historical maps. These will provide information about what an area looked like, often offering the building’s footprint and surrounding landscape. Timespan studies will no doubt show growth, development and possibly changes to the buildings of interest. But what the rich resources don’t tell the researcher is information about the people connected to those buildings. Who lived or worked there? What did they do for a living? Did they move often? Did they change jobs regularly? These types of questions can’t be answered with just maps alone as they require a detailed census to go along with it. To fill this type of need, Geospatial Centre staff at the University of Waterloo Library embarked on a massive-scale digitization and geo-location city directory project – one that had started in 2019, has involved at least 40 staff members, and still has a couple years to go before completion. This paper will summarize the project thus far, with a focus on the journey of geocoding historical streets

    An analytical approach to modelling shear panels in steel beams at elevated temperatures

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    Shear buckling of beam webs in the vicinity of beam-to-column connections has been observed in many full-scale fire tests. This phenomenon can lead to force redistribution within the adjacent connections, and even influence the performance-based analysis of full-scale structures in fire. However, beam-web shear buckling for Class 1 beams at either ambient or elevated temperatures has not been well studied previously. In this work an analytical model has been created to predict the shear buckling behaviour of Class 1 beams in the vicinity of beam-to-column connections at ambient and elevated temperatures. The model considers the reduction of resistance of the beam after web shear buckling has occurred. It is capable of predicting the shear resistance and transverse drift of the shear panel from its initial loading to final failure. Several 3D finite element models have been created using the ABAQUS software, in order to validate the analytical model over a range of geometries. Comparisons between the theoretical and FE models have shown that the proposed method provides sufficient accuracy to be implemented and used in performance-based global modelling

    Large displacement FEM modelling of the cone penetration test (CPT) in normally consolidated sand

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    A new finite element model based on a large strain formulation has been developed to study cone penetration in normally consolidated sand. An auto-adaptive remeshing technique was utilized for handling the very large distortion of sand surrounding the cone tip. A frictional contact interface utilizing Mohr–Coulomb's theory was chosen to represent interactions between the surface of the cone and sand. To model the sand behaviour, the non-associated Drucker–Prager constitutive model was selected. ABAQUS, a commercial finite element software package, was used to implement the model. The explicit solution algorithm was chosen due to its effectiveness for complicated contact problems. Analysis results proved that the model successfully captured the cone penetration behavior in sand. In addition, a chart to predict internal friction angles based on cone tip resistance for different vertical effective stresses was provided. This paper also shows a typical distribution of sleeve resistance, tip resistance—penetration relationship, and typical contours of vertical, horizontal, and shear stresses in normally consolidated sand. Finally, a non-uniform resistance was found along the length of the friction sleeve. Copyright © 2003 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34878/1/287_ftp.pd

    Thermal-elastic stresses and the criticality of the continental crust

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    Heating or cooling can lead to high stresses in rocks due to the different thermal-elastic properties of minerals. In the upper 4 km of the crust, such internal stresses might cause fracturing. Yet it is unclear if thermal elasticity contributes significantly to critical stresses and failure deeper in Earth's continental crust, where ductile creep causes stress relaxation. We combined a heating experiment conducted in a Synchrotron microtomograph (Advanced Photon Source, USA) with numerical simulations to calculate the grain-scale stress field in granite generated by slow burial. We find that deviatoric stresses >100 MPa can be stored during burial, with relaxation times from 100's to 1000's ka, even in the ductile crust. Hence, grain-scale thermal-elastic stresses may serve as nuclei for instabilities, thus rendering the continental crust close to criticality

    The biomechanical effects of stapes replacement by prostheses on the tympano-ossicular chain

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    Hearing is a sequence of processes in which the ear translates sound waves into electrical signals, which are then sent to the brain where they are interpreted as sound. The ossicular chain of the middle ear is formed by three ossicles (malleus, incus, and stapes), of which the last and smallest, the stapes, vibrates, thus communicating with the inner ear through the stapes footplate. When abnormal bone formation immobilizes the stapes (otosclerosis), the passage of sound does not correctly occur and hearing can be compromised. In most cases, surgery is an option for its treatment. The stapes is totally or partially replaced by a prosthesis (stapedectomy or stapedotomy, respectively) allowing the passage of sound to the inner ear. This work presents a study on the behavior of different stapes prostheses, considering their biomechanical characteristics. The stapes was replaced by different prostheses, made of dissimilar materials: stainless steel, teflon, and titanium. The umbo and stapes footplate displacements for the models with these prostheses were obtained and compared with the displacements obtained with the model representative of the normal ear. In the models with prostheses, the displacements are found in the hole where the prosthesis is attached.info:eu-repo/semantics/publishedVersio
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