Annual Report 1998/1999

Research Program ISIS Canada is a multidisciplined research network encompassing 11 universities, 217 researchers, 84 associated companies and organizations, and 40 multidisciplinary research projects. The research introduces a new spin to filament wound and pultruded FRP composites in civil engineering. Infrastructure both new and repaired is outfitted with the latest generation of fibre optic sensing technology for remote monitoring. This program is unique in the world as it brings together ground-breaking research in civil, mechanical, materials, aerospace, and electrical engineering. Fibre Optic Sensing Two former research Themes have been merged to form one cohesive program focussing on fibre optic sensor technology for civil engineering structures. The ultimate goal is to ensure fibre optic sensing becomes as user friendly to install as conventional strain gauges, but with increased sophistication. The research is based on a new sensing device formed within an optical fibre called a Bragg grating. ISIS has applied the short gauge length fibre Bragg grating sensors in new bridges to monitor slow change over time as well as the bridge's response to passing traffic. This technology provides a new, unintrusive way to monitor the impact of traffic and excess loads, long-term structural health, structural components rehabilitated with FRP wraps, and vibration frequency and seismic responses of structures. Notable benefits include: reducing the tendency to over design structures, monitoring actual load history, and detecting internal weak spots before deterioration becomes critical. Research Projects Fibre Optic Structural Sensor Development Material Integration and Applications of Fibre Optic Structural Sensing Sensor and Optoelectronic Demodulation System Integration Serial Multiplexed Bragg Sensor Network Tunable Split-Electrode DFB Lasers Oxide Deposition for Bandgap Shifting of DFB Lasers Theme Director: Roderick Tennyson, Ph.D., P.Eng., University of Toronto Remote Monitoring Projects within this Theme cover designing economical data acquisition and communication systems for monitoring structures remotely. This includes developing a system whereby the data can be processed intelligently in order to assess its significance. By modeling new structural systems, predictions can be made on how specific sensing data gathered will affect the service life of the structure. To date, several bridges and structures across Canada have been equipped with fibre optic remote monitoring devices. A combination of commercially available components and those developed by ISIS have been used in the measurement configurations. Both new and rehabilitated structures are currently being monitored. One of the major challenges of this Theme is to develop a standardized intelligent processing framework for use with data records obtained from the various ISIS field applications. Also included in this Theme (in close cooperation with the Theme on fibre optic sensing), is the development of smart reinforcements. Using pultrusion technology, fibre optic sensors can be built into FRP reinforcements. Smart reinforcements and connectors eliminate meticulous installation procedures at the work site, resulting in construction savings. Research Projects Remote Monitoring Intelligent Processing of Sensor Data Smart Reinforcements and Connectors Field Assessments:   - Chatham Bridge   - Confederation Bridge   - Crowchild Bridge   - Hall's Harbour   - Headingley Bridge   - Joffre Bridge   - Sainte Émélie de l'Énergie Bridge   - Salmon River Bridge   - Waterloo Bridge Theme Director: Aftab Mufti, Ph.D., P.Eng., Dalhousie University Innovative Structures Creative approaches to new FRP reinforced structures are researched within this Theme. Aspects such as strength requirements, serviceability, performance, and durability are examined. The experimental program includes building and testing full-scale or scaled models to examine behaviour and provide design guidelines for construction details to be used in a field application. Glass and carbon FRPs can be used for reinforcing cast in-place and pre-cast concrete. It can take the shape of rebars, stirrups, grating, pavement joint dowels, tendons, anchors and more. In bridge design, this material is used where longer, unsupported spans are desirable, or where a reduced overall weight, combined with increased strength, could mean greater seismic resistance. A light-weight, FRP-reinforced structure can reduce the cost of columns and foundations and can accommodate the increasing demands of heavier traffic loads. Field applications resulting from research in this Theme are outfitted with the newest generation of fibre optic sensing systems for remote monitoring. Accurate monitoring of internal strain is key to securing infrastructure owners' confidence in the material and design configuration. The practical significance of monitoring a structure is that changes which could affect the structural behaviour and load capacity are detected as they occur, thereby enabling important engineering decisions to be made regarding safety and maintenance considerations. Research Projects Innovative Bridge Deck Structural System Integrated Sensors and FRP for Concrete Concrete Structures Reinforced with Smart FRP Rebars and Grids Corrosion-Free Prestressed Masonry FRP Anchor for External Prestressing Serviceability of FRP Reinforced Concrete Structures Effect of Temperature on FRP Reinforced Concrete Structures Innovative FRP Ground Anchorage Application of Filament Winding Technology Theme Director: Sami Rizkalla, Ph.D., P.Eng., University of Manitoba Rehabilitated Structures The high strength and light weight of FRP and the fact that the material is now available in the form of very thin sheets, make it an attractive and economical solution for strengthening existing concrete bridges and structures. In rehabilitation projects, FRP serves to either confine concrete subjected to compression, or improve flexural and/or shear strength as an externally bonded reinforcement. There are numerous opportunities to apply this research as steel- reinforced concrete structures are in a continuous state of decay due to the corrosive effects of de-icing and marine salt, environmental pollutants, and from the long-term effects of traffic loads that exceed design limits. FRP patching and wrapping is the state-of-the-art method of repair and strengthening of structures. Research projects in this Theme address issues of performance and durability of FRP rehabilitation methods, and investigate the monitoring of structures through the use of integrated fibre optic instrumentation. This new technology will lead to the optimum maintenance and repair of infrastructure. Research projects include developing smart repair technologies whereby fibre optic sensors are embedded in the FRP wraps. Field applications resulting from this Theme cover a diverse range of structures under corrosive and cold climatic conditions. Research Projects Rehabilitation and Strengthening of Concrete Structures Smart Wraps for Corrosion Repair and Monitoring Evaluating the Effect of FRP Wraps on the Rate of Corrosion in Chloride Contaminated Concrete Smart FRP Wraps for Cold Region Applications Repair of Corroded Concrete Structures Field Demonstration of Intelligent Bridge Rehabilitation and Strengthening Sprayed FRP Matrix Composite Use of FRP in Timber Structures Theme Director: Kenneth Neale, Ph.D., Eng., Université de Sherbrooke Design Guidelines and Manuals As part of a separate theme, each of the four research areas is developing design guidelines and manuals which will be made available to the design and construction industry. The manuals also serve to expedite the acceptance of codes and form a vital component of transferring the technology to the infrastructure sector.

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