Short Biography:

Hassan Saffarini is the Structural Engineering Manager at NORR Architects Engineers Planners, Toronto and is a Senior Project Manager with 30 years’ experience in the design and project management of major building and infrastructure projects. He has a PhD in Structural Engineering and Structural Dynamics from the University of California at Berkeley and is a graduate of Leeds University, UK. Dr. Saffarini is an Adjunct Professor of Civil Engineering at Ryerson University and he lectures at the University of Toronto. Dr. Saffarini has authored many publications in international journals in the areas of structural engineering and seismic resistant designs. He was a professor of Civil Engineering at the University of Jordan for 25 years and was a founding partner and an Executive Vice President of Consolidated Consultants, Jordan before relocating to Canada.  Over the years he has worked on many heritage and archeological sites, and provided services to such organizations as UNESCO and the American Center for Oriental Research. On the Union Station Revitalization project he worked closely with the heritage architect and Parks Canada to make sure that all proposed interventions are in compliance with standards and guidelines for the conservation of historic places in Canada.

Abstract:

The City of Toronto’s “Dig Down” – Union Station revitalization project entails building a retail mall below the station’s viaduct structure and part of its head house. This 25,000 square meter footprint construction is taking place while the busiest transportation hub in Canada continues to operate without interruption. The 650 million dollar project covered all components of the station, including the Head House building, completed in 1920 and recognized as one of Canada’s most treasured heritage sites. The massive expansion of commercial and concourse space was however performed below the entire viaduct structure and part of the Head House.

The concept that was adopted for expanding downward basically entails supporting the track slab on vertical props that are founded on bedrock and jacking the slab upward. The column is then cut and a new column is spliced and is founded on new footings on bedrock. A number of other considerations were made to ensure the successful load transfer and minimum movement of the track slab. Different bearing concepts were employed for the shores including micropiles, ring beams and bearing plates. In total 184 columns are to be extended by this procedure. Other structural innovations were applied including a load transfer by use of storey-high trusses that doubled the available span for the loading dock. Another load transfer widened the mall corridor by column removal through a complex system of load sharing between the old structure and a new steel framing using a four stage jacking and de-stressing.

A rigorous monitoring program was crucial to make sure that the structure supporting the tracks and platforms moves within an acceptable amount while its foundation is uprooted and is replaced to make room for the new mall. This is one of the most extensive monitoring program that has been performed in Canada and has offered many lessons in terms of the need for precision monitoring of buildings undergoing major retrofits.

Attendants:

The presentation is of interest to the general audience and would be of particular interest to civil and structural engineers.

Max. No. of Participants:

No limit