Track 2: DESIGN - PLANNING THE CONSERVATION OF HISTORIC PLACES / Volet 2 : Conception - Planifier la conservation de lieux historiques

Making the case for base isolation of heritage structures in low and moderate seismic zones

Friday, October 13
8:30 AM - 10:00 AM

Around the world, base isolation is widely used in high seismic zones to protect new and existing structures from earthquake ground motions, and is very effective in reducing seismic demands for low-rise, stiff structures. Heritage buildings tend to be low-rise masonry-based structures; by their nature, these structures are stiff and brittle. It is widely understood that this type of construction is particularly at risk under earthquake loading, and that many heritage buildings need to be upgraded for seismic loads even in areas of moderate to low seismic hazard such as eastern Canada. Conventional seismic upgrades can result in significant structural interventions to add strength to the structure and rationalize load paths. These upgrades are often in conflict with the goal of preserving heritage fabric. To date, base isolation has not been extensively used in Canada; however, design requirements for base isolation are now included in the 2015 NBCC. This paper provides an overview of base isolation as applied to heritage buildings, and looks at the effectiveness of using base isolation on heritage buildings in regions of low and moderate seismicity by comparing the relative costs of conventional and base isolation seismic upgrades for heritage buildings in Ottawa. It is concluded that base isolation as a seismic upgrading solution for heritage buildings in low and moderate seismic zones is not only a viable option, but is in fact more effective and has greater benefits than in high seismic zones.

Learning Objectives:

Daniel Carson, P.Eng., CAHP

Senior Principal
WSP Canada Inc.

Co Presenters Dan Carson and David Arnold both WSP
Dan has over 35 years experience in structural design and construction of new buildings, investigation and restoration of existing buildings. Some of his work has included the Renewal and Seismic Upgrade of the Victoria Memorial Museum of Nature and the Rideau Hall Greenhouse Rehabilitation including the restoration of the 1906 Palmhouse. In 2014 to 2015, Dan was the structural lead for a seismic evaluation of the entire Center Block and Peace Tower, including a 3-dimensional earthquake analysis of the buildings. The study investigated the impact of various upgrade scenarios, including base isolation, on the heritage fabric of the buildings. Dan is currently the Lead Structural Engineer on the Certre Block rehabilitation project.
David has 14 years’ experience in structural design in New Zealand and Canada. David is a specialist in seismic design of new buildings and the assessment and seismic upgrading of existing buildings. Some of his recent work includes the seismic assessment and seismic upgrade of the former Nortel campus buildings in Ottawa. In 2015 David was the technical lead for the seismic evaluation of the Canadian Parliament Center Block building and the West Memorial Building in Ottawa. Both these evaluations studied base isolation of these heritage classified buildings as a potential seismic upgrade option.


Send Email for Daniel Carson

Send Email for Tom Morrison


Making the case for base isolation of heritage structures in low and moderate seismic zones

Attendees who have favorited this

Please enter your access key

The asset you are trying to access is locked. Please enter your access key to unlock.

Send Email for Making the case for base isolation of heritage structures in low and moderate seismic zones