Stay-In-Place (SIP) formwork systems are widely used for concrete slabs in industry due to their relative ease and speed of construction. Conventionally, corrugated metal sheets or precast panels are used as formwork. In recent years, the SIP formwork technique has been proposed in conjunction with Fiber Reinforced Polymer (FRP) composites. The resulting system combines the construction advantages of SIP formwork with the durability and corrosion resistance of FRP materials. Bridge decks are a particularly enticing application due to their exposure to harsh environmental conditions and the need for rapid construction to minimize traffic disruptions. This study broadly evaluates FRP SIP formwork for concrete bridge decks both experimentally and numerically. In total, 9 full scale bridge deck sections, 32 small scale decks and more than 40 auxiliary tests were conducted, including the construction and testing of a full bridge at scale. Additionally, a numerical model was developed to predict punching shear failure based on the theory of plates and shells. Experimental testing was conducted on two FRP SIP form configurations, namely flat plates with T-shape stiffeners and corrugated plates, and used a variety of different detailing and geometries. Some of the investigated parameters included the width effect of bridge deck section tests, the effect of deck span, the effect of bond at the FRP-concrete interface, the panel-to-panel splice configuration, concrete strength, and boundary condition at support, including a monolithic connection with precise girders. Results of the study include the determination of a critical aspect ratio for bridge deck sections, optimization of the panel-to-panel splice detail, and an assessment of the in-plane restraint available to interior span bridge decks. The numerical model, based on the Levy solution for loaded plates, produces a flexural response for a variety of bridge deck configurations and geometries. A failure criterion was applied to establish the punching shear capacity. The model was evaluated against experimental results and provided good correlation. It was then used to investigate a variety of FRP plate thicknesses, spans and effective widths for full scale FRP SIP formwork bridge decks. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2013-10-11 15:55:26.546

Terraces have been a common design element in Mid-Atlantic formal landscapes during the eighteenth century. Their roots in recorded Western history can be traced back to the Roman Empire and the Italian Renaissance. Because of the scattered research and a lack of a systematic approach to the study of historic landscapes, terraces have been an overlooked design feature. This thesis serves to synthesize research into a terrace typology that can be used to systematically document a terrace site, determine its significance, choose a preservation strategy, and interpret the landscape. To validate the effectiveness of the proposed terrace typology and its components. this project studied the Virginia plantation Menokin and its terraced landscape. The terrace typology is one possible tool to be employed as a first step in the examination of systematic approaches to the study of historic landscapes that can contribute to the development of the profession and expand the knowledge of the cultural environment. / Department of Landscape Architecture

No description available.

Full-depth precast panels are used in concrete bridges to provide several benefits such as faster construction, lower cost and reduced constructional hazard. However, one construction drawback is that connectors are required to transmit horizontal shear across the interface between the girder and deck. Shear connector performance is characterized by a series of experiments performed on part of a bridge system that mimics a full-depth precast deck on concrete girder with a pocket-connector-haunch system. Following initial breakaway of the adhesive bond within the haunch region, the specimens slide with frictional resistance provided by the clamping force of the anchor bolt. This leads to bolt yield with an observed sliding friction coefficient of 0.8 (+/- 20%) with lower values occurring at higher displacements. It is concluded that for a viable connector system to be developed a key feature is to have sufficient stirrups in the neighborhood of the anchor bolt to form a non-contact splice and to ensure the high pull-out force can be sustained without leading to premature beam failure. The successful implementation of a full-depth precast deck-panel system requires the use of a viable design methodology that properly accounts for system behavior. The design of a deck-haunch-girder system uses a truss modeling approach to design for the shear forces created by service loading. The truss model approach is considered more suitable for a concrete member due to the premise that the member will be substantially cracked at an ultimate limit state and that traditional beam theory does not account for the decreased ability of shear stresses to transfer across open cracks. Experimental results from Chapter II, such as the friction coefficient mu, are used along with a previously developed crack angle model to layout the geometry of the truss within a deck-panel span. Design solutions are presented utilizing the Rock Creek Bridge in Parker County, Texas as an example structure.

Most of the pollution found in highway runoff is both directly and indirectly contributed by vehicles such as cars and trucks. The constituents that contribute the majority of the pollution, such as metals, chemical oxygen demand, oil and grease, are generally deposited on the highways. These can become very harmful and detrimental to human health when they come in contact with our water system. The connecting tie between these harmful highway-made pollution and our water system, which includes our ground waters and surface waters, is rainfall. The main objective of this runoff study was to characterize and assess the quantity and quality of the storm water runoff of a bridge deck that discharged into a receiving water body. The bridge deck and the creek were located in the coastal margin region in the southeast area of Texas on the border of Harris and Galveston counties. Flow-activated water samplers and flow-measuring devices were installed to quantitatively determine the rate of flow of the bridge deck and determine different pollutant loading by sampling the receiving water body (Clear Creek). The collected samples were analyzed for total suspended solids, toxic metals, and other relevant constituents of concerns. The results illustrated that the runoff from the bridge deck exhibited low total suspended solids concentrations (which were highest in the creek). However, other metal constituents like the zinc and cooper concentration were high and above standards. The phosphate concentrations in the creek were the highest and exceeded EPA standards. Several nitrate concentrations were also noticeably above EPA standards.

This research focuses on the creation, validation, automation, and deployment of a nondestructive vertical electrical impedance (VEI) bridge deck assessment apparatus. A multichannel impedance analyzer with a moving platform is developed that can assess the deterioration state of a bridge deck without stationary traffic control. The multichannel apparatus is capable of taking over 500 impedance samples a second and can scan a bridge deck over 500 times faster than more traditional techniques. This research also shows VEI measurements are inversely proportional to the diffusivity of ions through concrete and that an impedance measurement frequency of 25 kHz is the most predictive measurement frequency of diffusivity. Finally, this research demonstrates the utility of VEI measurements by inspecting five asphalt overlaid bridges. VEI measurements were sensitive to defects in membranes and are one of the only nondestructive measurements that provide useful information about the deterioration state of asphalt overlaid bridge decks.

No description available.

No description available.

Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 83-87). Also available on the World Wide Web.

No description available.