Two attempts had been made by others to build two high-rise condo towers on the site of the former Gaslight Square retail strip at 10th Ave and 4th Street SW, Calgary, Alberta. Centron, a developer, decided to buy it and changed the concept to a single building, mixed-use office retail development. The site was already excavated and seven levels of underground parking completed so a considerable amount of structural redesign was necessary; which includes the upgrade on the existing foundation system.
Designed by RWH Engineering, 80 micropiles are installed 20 to 30 feet below the existing footing to support the additional load. As the installation was undertaken in a 7th floor underground parkade, HCM had to deal with limited access and low overhead clearance. Man-portable drilling equipment was used to compile with these limitations.
Despite the challenges, the project went well with HCM scope of work being completed on schedule. The pile capacity is confirmed by one verification test and five proof tests.
Location: Calgary, Alberta