Seismic Rehabilitation
of Eaton's Building
Montreal, Canada
Covered Area : 1,000,000 sq.ft.
Construction Cost : $110 million.
Savings : More than 50% in seismic upgrade cost and time.
The existing Eaton building is located in the heart of
the shopping district in downtown Montreal. This nine-storey building was
built in several phases, from 1925 to 1959. It has both concrete and steel
frames. The Eaton building has a beautiful stone façade. The existing
structure derived its lateral stability mainly from the perimeter masonry
walls, partition walls and concrete frames. The preliminary analysis indicated
that the resistance of existing structure was less than half of the lateral
seismic forces specified in the National Building Code of Canada.
In 2000, new ownership of this building prompted a major redevelopment of
this building. The planned renovations lead to significant changes in the
interior and further diminished its seismic resistance capacity. It was necessary
that seismic rehabilitation work be undertaken along with the architectural
renovations to protect the existing and new investment.
Of the several schemes, the introduction of supplemental damping using Pall
Friction Dampers in steel bracing was considered to be the most effective
and economical solution for seismic upgrade. This novel upgrade approach significantly
reduced the drifts and base shear while greatly minimizing the strengthening
of the existing members. As the seismic forces exerted on the structure are
significantly reduced, the system offered savings in upgrade costs. Besides
savings in the upgrade cost, the saving in life cycle cost could be significant
as damage to the building and its content is minimized.
A total of 161 Pall Friction Dampers of 500-700 kN slip load were used. The
building was completed in 2002.