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Publication Experimental Assessment of the Current Load Rating Procedures for a Corroded Steel Ridge Girder in Massachusetts(2020-01-01) Knickle, Brendan T.The work conducted for this project involves an experimental assessment of the Massachusetts Department of Transportation’s (MassDOT) existing procedure for determining the resistance of a corroded steel girder end when load rating a bridge. Three steel girders with significant corrosion developed over a 79-year service life were obtained from a recently rehabilitated bridge and loaded to determine the girders corroded resistance. A testing rig was designed in the UMass Amherst Brack Structural Testing Laboratory to both apply a shear dominated load to the corroded girder and withstand the developed lateral loads throughout the analysis. Reaction force data obtained from the load testing was compared against the corroded web factored resistance determined from the MassDOT LRFD Bridge Design Manual. Resistances were under predicted by 75% for specimen 1, 37% for specimen 2 and the manual predicted no resistance for specimen 3. Lastly influences for the discrepancies between manual resistance and experimental resistance are determined.Publication Integrated Solar Technologies with Outdoor Pedestrian Bridge Superstructure Decking(2015-01-01) Racz, RichardSolar technology has been a major topic in sustainable design for many years. In the last five years, however, the solar technology industry has seen a rapid growth in installations and technological advances in cell design. Combined with a rapidly declining overall system cost, the idea of introducing solar technology into a wider range of applications is becoming a focus for engineers and scientists around the world. So many variables which alter solar energy production, such as the sun and surrounding environment, determine whether a solar design is beneficial. This thesis presents a bridge deck surface integrated with solar cells tested under all AASHTO LRFD pedestrian bridge loadings. A detailed solar analysis of the University of Massachusetts’s campus is presented to determine if solar integration is even plausible for the Northeastern United States with the energy limitations created by the deck integration, as well as an economic evaluation of the deck design. The purpose of this thesis was to determine if a walking surface could be integrated with solar technology and be a plausible alternative to conventional walking surfaces, while providing a source of sustainable power.Publication NONLINEAR FASTENER-BASED MODELING OF COLD-FORMED STEEL SHEAR WALLS UNDER LATERAL LOADS(2019-01-01) Derveni, FaniAs cold-formed steel (CFS) has increasingly been used in low- and mid-rise construction across United States, it becomes necessary to capture and evaluate its lateral response in both, sub-system/member level and system level. The main lateral resisting system in cold-formed steel construction is shear walls; shear walls are the focus of this work. In particular, the present study aims to shed light on the response of wood sheathed coldformed steel (CFS) shear walls exposed to earthquake events through nonlinear high fidelity fastener-based modeling. The numerical approach is fastener-oriented including nonlinear experimental-determined connector elements for steel-to-sheathing connections, orthotropic oriented strand board (OSB) modeling for sheathing material, contact implementation and linear spring hold-down simulation for preventing uplift. The numerical results are compared and validated by a previous experimental study, assessing the efficiency of fastener-based modeling to capture the peak load and displacement, the failure mechanisms and the overall structural behavior of sheathed cold-formed steel shear walls. Furthermore, cold-formed steel to sheathing shear fastener response is computationally examined and validated by a previous experimental work. The main goal of this work is to introduce a robust computational tool capable of demonstrating how wood sheathed cold-formed steel framed shear walls behave during a lateral load event with potential use in any cold-formed steel screw-fastened connection system, such as diaphragms and in any fastener-based cold-formed steel full building simulation.