University of Toronto Faculty of Law

TTC Steels Launch Shaft

The expansion of the Faculty of Law building at the University of Toronto incorporated the addition of another storey to the existing building. The increased loading required an upgrade to the capacity of the building foundation. HCM proposed an innovative solution to install micropiles next to the caissons to accommodate the additional loading. The micropile foundation was designed by RWH Engineering Inc. (RWH), an HCM Group company.

Specialty equipment was required to install the micropiles inside the existing building, as there was only four meters of headroom in some areas. HCM used a low head room drill to install micropiles to depths of 18 meters. The micropile design required triple post-grouting to achieve the necessary bond between the grout and the soil. The soil encountered was comprised of layers of sand, silt, and clay. To confirm the design adhesion, a sacrificial load test was performed to 250% of the ULS load.

This project is an example of how HCM/RWH can offer alternative foundation solutions to meet the needs of any project, including projects with challenging site restrictions.

Client: Eastern Construction

Location: Toronto, Ontario

Talbot Street

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.

LRT Slope Protection at Retaining Wall

LRT Slope Protection at Retaining Wall

LRT Slope Protection at Retaining Wall

HC Matcon (HCM) and RWH Engineering (RWH) reacted quickly after being contacted to provide a design-build solution for a slope failure that occurred during the excavation for a new retaining wall at the Eglinton LRT project. The 14m (45’) high slope was approximately halfway excavated for a permanent block retaining wall when it a sudden slip failure occurred creating concern for the adjacent properties. RWH designed a slope retention system with soil nails and shotcrete facing to remediate the slope and allow for continued excavation. Using a TEI drill mounted on an excavator, HCM was able to reach the top of slope to install soil nails.  Shotcrete was applied by a nozzleman in an elevated work platform. Once the exposed portion of the failed slope was stabilized, excavation was able to resume and HCM continued installing additional lifts of anchors and shotcrete to the base of the finished slope for a total protected area of 1250m2 (13,500 SF).

HCM and RWH provided an efficient solution, adapting the slope protection design to assist with the durability of the permanent retaining wall. Real-time design changes were made onsite to accommodate additional area required after installation had already commenced, enabling the original retaining wall construction to resume as fast as possible. 

 

Location: Toronto, ON

Customer: Metrolinx

LRT Slope Protection at Retaining Wall
LRT Slope Protection at Retaining Wall

Slope Remediation

Slope Remediation

Slope Remediation

HCM and RWH Engineering provided a design build solution to remediate a failing slope at a project located in Western Ontario.

Prior to HCM’s involvement, the site was excavated 7m into a silty clay at a 1:1 slope.  HCM was contacted after the slope began to fail and large movements were seen.  After RWH completed the design solution, HCM worked from a boom lift to install anchors with a TEI drill mounted on an excavator to stabilize the slope.  HCM applied meshed shotcrete directly to the face of the slope and tied in the system by post-tensioning the anchors.  Utilizing real-time engineering and quick execution, HCM was able to complete the installation without substantial ground loss, allowing for work onsite to be conducted safely.

HCM has applied shotcrete with tieback anchors as slope protection systems on many job sites with poor soils or tight sloping constraints. This project is an example of HCM’s and RWH’s ability to act quickly and adapt to changing site conditions to provide effective solutions.

Location: Coruuna, ON

Customer: Cope Construction and Contracting Inc.

Slope Remediation
Slope Remediation
Slope Remediation

Eglinton LRT – Cedarvale Station SEM and SOE

Segmental Excavation Mining and Support of Excavation - Eglinton LRT - Cedarvale Station SEM and SOE

Eglinton LRT – Cedarvale Station SEM and SOE

The Eglinton LRT Cedarvale Station required the new structure to pass below the existing TTC subway below grade. HC Matcon Inc. (HCM) was contracted by the Crosslinx group to perform segmental excavation mining (SEM) and support of excavation (SOE) below the existing subway tunnel. HCM performed the detailed excavation and the installation of dry mix shotcrete in 6 galleries for the phased installation of structural needle beams to support the tunnel above.
HCM’s SEM work involved excavation in 1.1m sections, installation and stressing of temporary supports, and installation of accelerated fibre-reinforced dry mix shotcrete for the walls and base slab. Due to strict movement tolerances of the tunnel above, a unique prestressed waler incorporated with shotcrete shoring was implemented. Special design and constructability considerations were coordinated with the designer to ensure safety during excavation mining. HCM installed a waler and tie-rod system that was prestressed from between the walers to achieve the deformed shape required by designers.
Due to HCM’s knowledge and experience with shotcrete and associated applications,
this unique project was executed successfully and to the satisfaction of the project
team.

Location: Toronto, ON 

Customer: SKYGRiD Construction Inc.

 

Segmental Excavation Mining and Support of Excavation - Eglinton LRT - Cedarvale Station SEM and SOE
Segmental Excavation Mining and Support of Excavation - Eglinton LRT - Cedarvale Station SEM and SOE
Segmental Excavation Mining and Support of Excavation - Eglinton LRT - Cedarvale Station SEM and SOE

Midtown Lofts

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

Telus Sky tower - HC Matcon

Telus Sky tower

The Telus Sky tower will be the 3rd 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

HC Group - Telus Sky Shoring Clean Wall
Telus Sky tower - HC Matcon
Telus Sky tower - HC Matcon
Telus Sky tower - HC Matcon

University of Ottawa STEM Complex

University of Ottawa STEM Complex

HCM installed a 36,000 SF shoring system for the new STEM Complex at the University of Ottawa. To reduce the shoring schedule during the harsh Ottawa winter, HCM deployed double crews, 24 hours a day for both vertical drilling and anchor installation. Constant adaptation to the soil conditions was needed due to the presence of soft clays, cobbley till, and flowing sands. Multiple freeze-thaw cycles made for challenging site conditions requiring proficient site communication to ensure a productive and safe jobsite. RWH Engineering Inc. produced an efficient shoring solution and by self-performing the precision monitoring allowed for the design to be verified closely with the excavation procedures. In-house engineering support also ensured there was no downtime caused by unforeseen conditions or site issues.

HCM worked alongside the other contractors to expedite the project to the bottom of the 17 meter deep site in 3 months.

Location: Ottawa, Ontario

Customer: R.W. Tomlinson Ltd

Upper House Condominiums

Upper House Condominiums - Caisson Wall Piles and Lagging

Upper House Condominiums

HCM completed the shoring for the eight storey Upper House Condominium project which required a 12m deep excavation for two levels of underground parking. A tied-back shoring system comprised of piles and lagging with caisson wall adjacent to an existing residence was installed. 

Typical to developments in Toronto, there were encroachment restrictions on the south side of the site which only allowed for the tiebacks to extend a maximum of 6.2m to the neighbouring property line. To work within the limited space restrictions, RWH Engineering Inc. designed a system utilizing an upper row of double splayed anchors. Post-grouted strand anchors were installed to achieve the required load capacity in the soils. HCM with the supervision of RWH completed a load testing program to determine the optimal number of post-grout cycles required to meet the anchor design. Reducing the post-grout cycles resulted in schedule savings to the project.

Further, the shoring design was finite element modelled to allow for comparison against the monitoring results and ensure the shoring performed adequately throughout the construction. 

HCM and RWH worked together to produce a design-build shoring re-design which was tailored to the specific requirements of the project and resulted in cost and schedule savings.

Location: Toronto, ON 

Customer: SKYGRiD Construction Inc.

 

Currie Barracks Residential Development

Currie Barracks Residential Development

HCM was contracted to provide the design and installation of shoring system for a multi-family condo development in the Currie Barracks area SW Calgary. Conventional cantilever pile and timber lagging shoring system was used to support the excavation for the foundation wall along 50% of the perimeter of the entire building footprint. Most of the shoring was offset from the foundation wall and the remaining portion was used as a blind form for the concrete formworks. This was determined by the presence of the City of Calgary Utility Right of Way (URW) and the close proximity to the property line at the areas that required shoring. The depth of excavation varied from 4-5 metres below grade. The shoring was regularly monitored by an HCM field engineer in order to detect any unusual movement and/or anomalies which may occur in early stages of the excavation. If movement had occurred, an alternate design solution consisting of an internal raker bracing was prepared at early stages of the shoring design. This provided the owner/developer with significant cost savings as the shoring showed negligible movement for the duration of the excavation.


HCM completed this project on schedule and according to the planned stages of the progress requirements determined by the General Contractor.

Location: Calgary, Alberta

Customer: Lear Construction Management

Twinning Tunnels

Twinning Tunnels

The installation of a deep trunk sanitary sewer system in the bedrock beneath Erin Mills Parkway in Mississauga required an innovative approach for shoring manholes. For this project, HCM was contracted to install nine caisson wall compression rings at various locations. RWH Engineering Inc. (RWH), an HC Group company, provided an economical design for the shafts which had diameters of up to 11 meters and depths up to 50 meters.

RWH overcame several design challenges on this project including the consideration of the compression rings to withstand large uneven surcharges due to a close embankment as well as significant crane loads. To ensure the integrity of the shoring system, RWH provided the precision monitoring services.

This project required the installation of the compression rings into the bedrock to support the overburden. HCM successfully implemented RWH’s innovative design which did not include a bench at the top of the bedrock, as commonly seen in compression ring design. This resulted in a reduced diameter of the compression rings, significantly reducing the amount of bulk excavation required as well as installation time.

The project exemplifies HCM’s ability to find effective solutions to complex projects to minimize construction time.

Location: Mississauga, Ontario

Customer: McNally Construction Inc.

Odeon Ronmore Development

Odeon Ronmore Development

HCM was contracted to provide the design and installation of shoring system for a mixed use commercial development in the main corridor of the Garrison Woods area SW Calgary. RWH designed a tied-back pile and timber lagging shoring system to support the vertical excavation for the foundation wall along the majority of the building perimeter. Due to overhead power restrictions and minimal clearances to the property line, the laneway side of the project was supported by a soil nailed shotcrete system. The laneway shoring presented various challenges including anchor encroachment limitations that could not exceed 6.0m to the adjacent property. Anchors were tightly spaced and injection grouted bars installed to gain increased soil adhesion. Regular site inspections and monitoring was performed by RWH to review the performance of the shoring and confirm the design during all stages of the excavation. The shoring was designed for a maximum excavation depth of 10m below grade for a total of 13,200 SF of shoring area.

HCM finished this project on schedule working with the General Contractor to escalate excavation activities and meet the occupancy milestone outlined by the owner.

Location: Calgary, Alberta

Customer: Chandos Construction Ltd.