Proceedings - 13th International Workshop on Micropiles - 2017, Vancouver, BC, Canada, (ISM, DFI, ADSC)
HERITAGE FAÇADE SUPPORT AND EXCAVATION SHORING – A MICROPILE CASE HISTORY
Amanda Gordon, B.Eng., Michael Sousa, P.Eng. Brian Isherwood, MICE FCSCE P.Eng.
Originally built in 1927, the distinctive terracotta trim and red brick façade of the Canadian Westinghouse Building in Toronto’s entertainment district is preserved in-situ on a temporary frame supported by Case 1 micropiles also employed as vertical members in a temporary excavation shoring system. Two street facing façades of this 6 storey heritage building were supported while the remainder was demolished to make way for development, including two towers and five underground parking levels. A large diameter soldier pile excavation support system was originally planned around the site, however, proximity of a gas main and the preclusion of street closures due to traffic congestion and light rail tracks, required a hybrid solution with small diameter piles. The façade support frame was founded on two rows of vertical 356 mm diameter piles, designed to act in tension and compression to suit wind loading on the facade. The row of micropiles closest to site were also designed to withstand lateral earth pressures and allow for potential bedrock expansion that is known to develop in Toronto shales following excavation.
|article #2636; publication #1033 (ISM- 2017)|