Durability of ultra-high performance concrete as joint-fill material for precast bridge desk panels

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The majority of bridges in North America are becoming obsolete and structurally deficient as they are nearing the end of their service life. Many aging bridges in Canada will need major rehabilitation in this century. Current estimates place the national bridge infrastructure funding deficit in Canada at more than $20 billion per year. Additional indirect costs such as those incurred due to closures of major transportation routes during construction will have severe consequences on the nation's economy and will have to be addressed. To reduce the costs associated with rehabilitation or replacement of bridge infrastructure, there has been a strong desire to minimize construction time and the impact on the surrounding environment and transportation network involved. This has led to a push for the development of Accelerated Bridge Construction (ABC) practices, which use modular precast bridge components that are installed on-site, rather than conventional cast-in-place (CIP) concrete bridge decks. Whether the project is the construction of a new structure, or the rehabilitation of an existing deteriorated structure, implementing precast bridge deck panel systems can greatly accelerate the project schedule. The proposed research project aims to address one aspect of ABC by developing long-term performance data of ultra high performance concrete (UHPC) jointed precast prestressed concrete panel (PPCP) bridge systems subjected to fatigue loads and temperature variations. A scaled model of the panel segments with UHPC joints and shear pockets will be tested and the behaviour of the joints in negative bending will be investigated. This project will determine suitable size and shape of sheer pockets when using UHPC. Data from a bridge-way in motion installation on Morris Bridge in Manitoba will be analyzed and a finite element model of the structure will be verified and used to predict algorithms to determine the fatigue life of bridges. Developing such an approach will be a significant contribution to current bridge design and maintenance practices.