2016 Archives - HCM Group

Talbot Street

HCM completed the design-build shoring for the Azure condominium project in downtown London. Due to the soil conditions encountered during initial drilling, a full depth caisson wall was installed for the construction of a two storey underground parking structure.

A combination of tiebacks and internal struts were used to support the 12.0m deep excavation. After piling was complete tieback encroachment became no longer possible along the west wall and had to be converted to a double rakered system. As the foundation structure was entirely precast this presented unique challenges when using rakers. RWH worked together with HCM and the Developer to make the internal bracing system work around the precast panels and designed the system to allow for removals to help facilitate the constriction process.

The shoring was constructed next to an existing church sensitive to movements. Excavation procedures were modified and extra considerations were taken in both the design and construction to reduce any movements and vibrations. Further, RWH completed target, inclinometer and vibration monitoring to verify the shoring performance throughout construction and ensure minimal impact to the church structure.

Client: The Tricar Group

Location: London, Ontario

Aligning with the HCM group’s core value of sustainability, the Azure project became the first LEEDS condominium project in London’s history.

Midtown Lofts

On this project, HCM in conjunction with RWH Engineering Inc. (RWH), provided the owner with a complete design-build package and precision monitoring services for an 8.5m deep temporary shoring system.

RWH produced a tailored piles and lagging shoring design. As tiebacks were not feasible on the project due to encroachment limitations, RWH provided a waler and raker design that minimized interference as construction progressed.

HCM worked closely with the general contractor during pile installation and lagging to ensure that excavation proceeded safely and on schedule. Precision monitoring was implemented and reviewed by RWH throughout the project to confirm the integrity of the shoring system and surrounding infrastructure.

Client: GUPM Construction Managers

Location: Kitchener, Ontario

Telus Sky tower

The Telus Sky tower will be the 3^rd tallest building in Calgary with the deepest basement excavation in western Canada. HCM Group took on the challenge of creating a shoring system suitable for the 30m excavation. RWH designed the shoring system with an 11m deep perched secant wall and shotcrete was used in the bedrock to stabilize the rest of the excavation. HCM contractors were responsible for the installation of the perched secant wall and the shotcrete.

The project was not without its challenges. These challenges included neighboring structures, the LRT system that ran adjacent to the site, existing Telus utilities and limited working space within the excavation. An extremely sensitive Telus duct bank ran adjacent to the excavation and the movement of the bank had to be kept to a minimum. RWH had to take this into consideration when designing the wall. The footprint of the excavation was only 2,100m². HCM contractors were able to work strategically with other sub-contractors to ensure work could be carried out seamlessly in the small area. RWH provided precision monitoring of the shoring, neighboring structures and the LRT line. Monitoring reports were provided twice a week until the excavation reached sound bedrock and it was then reduced to weekly.

HCM Group were able to use their experience with similar past projects to design and construct a shoring system that was suitable for the 30m excavation. The shoring moved 75% of what was originally predicted, proving it was more than adequate.

Client: Icon West Construction

Location: Calgary, Alberta