Complex building in Ontario

The One (Toronto) by Sikander Iqbal, License CC BY-SA (https://creativecommons.org/licenses/by-sa/4.0/legalcode)

John Hopkins University – United States

Building use

Complex building

Country/Region

All Regions

Overview

Heavy structural steel and composite diagonal framing and composite perimeter mega-columns were adopted to enable the large open spaces that characterize the interiors of the building. In the retail space and throughout the building, no columns are required, and instead gravity and lateral loads are collected by the diagonal framing and transferred to the mega-columns on the perimeter.

Basic information (construction date, number of stories, gross floor area, adopted design code, engineer(s), Contractor(s), etc.)

Construction date: 2017-2026
Number of stories: 94
Gross floor area: 68,634m2
Adopted design code: Ontario Building Code; Building Code Act 1992
Engineer(s): RJC Engineers
Contractor(s): Clark Construction Management

Issue and/or innovation

The composite mega-columns were pre-reinforced with steel before being shipped to site. Once this was in place, the diagonal framing is an innovative system by itself, consisting of structural steel only in the first floors, to then transition into a mix of composite steel and reinforced concrete. The diagonal framing transfers the load towards the mega-columns in the perimeter. This allows for a very tall building with little need for interior columns.

Reason for composite solution

To enable the large open spaces that characterize the interiors of the building.

Specific solution/technical details

Megacolumns made of steel connected to the caissons and basement columns, spreading the tower’s load to the perimeter. Heavy structural steel until the ninth floor, which then transitions to composite steel and reinforced concrete, to only concrete.

Impact or effectiveness

Large open spaces, reduced need for interior columns.

References / Technical Papers Content

Verhey, T. (2021). The One Way To Build The Tallest Condominium Tower In Canada. Advantage Steel, 68(1), 36-37.
https://www.cisc-icca.ca/wp-content/uploads/2021/06/Advantage_Steel_Redesign-68_Winter-S.pdf

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