Research
The primary objective of my research program is to develop new bridge systems to meet the challenges of the 21st century.
Research is the process by which new knowledge is created and validated. For designers, the role of research is to enhance the quality and richness of ideas that make up the available supply of conceptual raw material for use in the design process.
My overall research objectives give rise to a number of individual research projects. Projects that are currently underway include the following:
New Bridge Systems in High-Performance Concrete
The purpose of this project is to define the primary features of structural systems that make efficient use of high-strength concrete. These systems will have thin slabs and webs and minimal reinforcing steel. They will be intensively post-tensioned in at least two orthogonal directions.
Concept for an efficient double-T system (view from below)
Fibre reinforcement as a substitute for crack control reinforcement in intensively post-tensioned members
The purpose of this project is to investigate the use of fibre reinforcement as a means of controlling shrinkage cracking in thin, high-performance concrete sections with little or no reinforcing steel.
External, unbonded tendons
The use of concrete bridge cross-sections with thin slabs and webs requires an intensive use of external, unbonded tendons. The purpose of this project is to develop simple, rational models for the behaviour of concrete girders prestressed with this type of tendon.
Test of 8 metre long beam with external unbonded tendons
Full-depth precast concrete panels for rapid bridge deck construction
The purpose of this project is to develop a system of standard precast concrete components that can be used for rapid construction and replacement of concrete bridge deck slabs on parallel longitudinal girders. The current focus of this project is to investigate the feasibility of polyurethane as a means of bonding precast concrete deck slab panels to steel girders.
Test of polyurethane joint between concrete and steel in shear
Sustainability
The objective of this project is to develop a rational basis for evaluating the environmental impact of bridge concepts and to adapt structural systems to maximize sustainability.
New structural applications of ultra high-performance fibre reinforced concrete
This project is led by Dr. Katrin Habel. Its current focus is on the use of this new material as a bonded structural overlay applied to existing conventional concrete. Work is now underway on an experimental and analytical study of the behaviour of layered composites of ultra high-performance fibre reinforced concrete and conventional concrete under extreme actions.
Next generation post-tensioning anchors
The size of anchorage devices is determined primarily by the compressive strength of the surrounding concrete. The post-tensioning anchors in use today have not changed significantly since the early 1960s, when most concrete used for bridges had a compressive strength of about 35 MPa. This research project seeks to reduce the size and complexity of anchorage devices to take advantage of the significantly higher strength of concrete that is currently available.
Post-tensioning anchorage specimen after test
Visualization of the flow of forces in concrete structures
Truss models (also called strut-and-tie models) are powerful tools in the design of concrete structures, because they allow engineers to express the flow of forces visually using remarkably simple analytical means. I am currently studying ways of extending the classical truss model to situations beyond its current range of application.
Bridge aesthetics
I am currently studying the cultural and social significance of several bridges in within Toronto and its immediate hinterland.
I am privileged to direct a talented, creative, and enthusiastic research staff.
May 18, 2007 | © 2007 Paul Gauvreau