Sunnybrook Health Sciences Centre

Milman was retained by mechanical/electrical engineering firm HH Angus & Associates to provide structural engineering services related to the expansion of the existing powerhouse at Sunnybrook hospital.

The expansion involved the erection of a second storey atop an existing powerhouse and the construction of a two-storey structure adjacent to it. Our detailed structural analysis of the existing building revealed that the expansion would overstress the existing footings, columns, and steel beams. We designed reinforcement, including drilled helical piles below the existing foundation inside the building. Both the addition and the new building were designed from structural steel and required the reinforcement of existing foundations due to extremely weak soil conditions.

The construction was scheduled in phases so that at any time at least two emergency generators (new or existing), housed within the existing building, were always in operation. Parts of the structure had to be removable to facilitate maintenance of equipment and dampers.
We designed the new structure, including strengthening of the existing, that could be constructed in independent phases that would not disrupt the operation of the building. Our team conducted thorough construction supervision due to complicated site conditions, and project administration. The project was completed on time and within budget.

This project was particularly challenging due to unexpected buried site conditions that were discovered during construction, and the phasing of the construction.