Milton Grade Separation

Client: BOT Construction
Location: Milton, Ontario

BRT Tomken Station

The Mississauga Bus Rapid Transit (BRT) project is a dedicated roadway for bus travel. It stretches 18 km from Winston Churchill Boulevard to Renforth Drive.

HCM’s scope of work for this project included all shoring and caisson work to accomodate the construction of transit stations, bridge underpasses and overpasses, and below grade roadways. HCM’s tender submission used shotcrete for roadway protection systems and two-sided shoring for bridge underpass/overpass construction. This unique design, completed by RWH Engineering Inc. (RWH), an HC Group company, resulted in many cost and schedule savings for the owner.

There were numerous jobsites that HCM coordinated during different stages of the project schedule which made communication between the HCM team, the GC and other sub trades critical. This project exemplifies the ability of HCM to assist owners and GCs in finding beneficial solutions for all parties.

Client: Metrolinx

Location: Mississauga, Ontario

TTC Steels Launch Shaft

The TTC tendered the Steeles Launch Shaft project as part of the much needed Shepherd subway extension into Vaughan. HCM undertook this project as a general contractor: self-performing the shoring, excavation, dewatering, and precision monitoring of the shoring system.

The shaft was 20 meters in depth and required removal of 20,000 cubic meters of material. RWH Engineering Inc. (RWH), an HC Group company, working together with T.H. O’Rourke Engineering, designed a three level strutted system of 460mm – 610mm diameter pre-loaded struts to brace the shoring walls. This design made the shoring system more durable as necessitated by the project due to the extended exposure to heat, cold and frost penetration as the excavated area was to remain open for a minimum of two years. The shoring was initially designed as piles and lagging with a portion of caisson wall, but was redesigned by RWH to a complete caisson wall as a result of these factors. RWH completed all monitoring which involved inclinometers, strain gauges, total stations, and piezometers. Final movement of the shaft showed less than 0.5% of the height. This project shows how HCM and RWH can perform a combination of construction activities, and provide the additional benefit of engineering and precision monitoring services, saving owners money while providing a safe shoring solution.

Client: Toronto Transit Commission

Location: North York, Ontario

Dufferin Jog Elimination

This project involved the extension of Duffering Street under an existing CN rail line and through the abutment wall of a century old CN bridge at Queen Street in Toronto. HCM performed a design-build tied back caisson wall solution for the main staging effort.

The geology of the soils was a combination of fills and wak silts over rock. The old bridge was jacked onto tower frames supported by cased micropiles. Low headroom caissons were installed by churn drilling with permanent liners. Further innovation included a tieback connection through abutments which avoided damage to the future surface of the structure.

HCM met scheduling requirements while performing several services throughout multiple phases, facilitating overall project success.

Client: Dufferin Construction

Location: Toronto, Ontario

Lakeview Water Treatment Plant

This project was part of the second phase of an expansion program to the region of Peel’s Lakeview Water Treatment Plant. Given the information provided at the time of tender, HCM proposed the use of shotcrete shoring for the site’s earth retention system. Later, due to an unforeseen influx of water into the excavation from a problematic sand lense and the resulting saturated soil conditions, shotcrete was found to no longer be a suitable solution for the site’s shoring. To address the issue, HCM devised a perched caisson wall system to cut off the flow of groundwater.

As fieldwork progressed, other fill soil conditions were encountered that were different from the geotechnical report issued at the time of tender. A change of the soil conditions, as encountered at Lakeview, would typically impact the project’s schedule because of the need for a redesign of the shoring system. HCM was able to respond with practical solutions to keep the project moving while updating the drawings to represent the design changes.

HCM can overcome most problems or restrictions to produce a final product that is desirable to all parties.

Client: North America Constructors Ltd.

Location: Mississauga, Ontario

Currie Reservoir – Continuous Caisson Wall

Increased Safety: We Used Horizontal H-Piles

This project is a part of a large upgrade to the Currie Reservoir in southwest Calgary, Alberta. The project included the installation of a caisson wall as well as horizontal shoring and underpinning.

The purpose of the installation of the caisson wall was to provide support for the existing pump-house structure as the excavation was taking place between the pump-house and underground water tank.
The retaining wall was designed by J.R. Spronken & Associates Ltd. as a Cantilever Secant Pile Wall with a maximum excavation depth of 8.0m below grade.
The length of the shoring wall is approximately 48 linear meters with total exposed surface area of about 370 square meters.
The pile sizes used include 760mm soldier piles and 610mm filler piles. The overall scope of the work consisted of drilling 28 soldier piles and 30 filler piles.

The client also approached HCM with the request to provide horizontal shoring/underpinning at the bottom of the excavation in order to provide a safe working platform for the connection of a 900mm diameter pipe between the pump-house and water tank. HCM completed this task by pushing a series of H-piles horizontally, using a hydraulic jack which was set-up on a specially designed steel frame system attached to the caisson wall.

HCM Contractors completed this project ahead of schedule and to the complete satisfaction of both the client and the engineer.

Client: PCL Construction Management
Location: Calgary, Alberta

Currie Reservoir

Horizontal Underpinning

This project consisted of an interlocking secant pile wall, combined with horizontal underpinning to accommodate a new connection to a pump house at the Currie reservoir in Calgary. The interlocking secant pile wall (caisson wall) allows for an accelerated construction schedule as it eliminates the ground loss that is present with the use of other styles of shoring. Where utilities were present, bracing supports were used to resist the lateral pressures present behind the filler piles.

Unique to this job was the installation of horizontal underpinning. The job required a new connection between the existing reservoir and pump house. To accomplish this task, a tunnel had to be created to accommodate the 900mm connecting water pipe. The underpinning provides support for the tunnel walls. The system worked well; after excavation, the resulting tunnel allowed safe access for the installation of the connection pipe to the pump house.

Because of the job’s proximity to the working water reservoir, special environmental precautions had to be taken in order to avoid contamination. Site-specific procedures were implemented; in instances where lubricating oils had to be used, for example when sliding the horizontal underpinning beams, food grade oils were used over hydrocarbon-based oils. As a result, the integrity of the water supply was maintained throughout the duration of the project.

Client: PCL
Location: Calgary, Alberta

CN Malton GO Station

Challenge: Build While Trains Are Running

Work on the Malton GO Station in Toronto, Ontario includes improvements such as new walkways and a tunnel for pedestrian access to new platforms.

HC Matcon’s scope of work, includes:

37 caissons at 30-inch diameter, and an approximately 25-foot deep shoring system with strand anchors.
The pile and caisson installation was challenging due to a number of factors. The train tracks, in close proximity to the work being done, were required to be fully operational.
Special precautions were taken for track protection and the safety of workers.
Due to the close proximity to Pearson International Airport, special precautions were taken to conform to the Greater Toronto Airport Authority’s guidelines for the operation of high-mast drills and cranes.
HC Matcon accommodated special staging requirements set forth by CN for work, such as the installation of the precast tunnel and track relocations.

HC Matcon will work with all parties involved in a project to ensure a swift execution with minimal conflicts.

Client: B. Gottardo
Location: Toronto, Ontario

St. Joseph’s Healthcare Redevelopment Project

Unique Soil Conditions

The future location for this tower is located immediately adjacent to the emergency wing of the existing St. Joseph’s hospital in Hamilton, Ontario. HCM is a recognized shoring contractor that will take on many challenges relating to foundation design.

On this particular project, HCM took on the tasks of:

shotcrete shoring
caissons
micropiles
excavation
site services
demolition with the constraints of limited access and project complexity.

A portion of the work was to be performed indoors, which required special care towards the patients of the hospital and the HCM workers. The original design for this inside work included conventional pad footings dowelled in to existing caissons five feet below the finished floor. The soil conditions are unique on this project due to the fact that the site is situated at the bottom of the Niagara Escarpment where bedrock is on an incline. This increased the depth required for adequate bearing stratum, requiring the entire area to be excavated and the perimeter shored. To save costs to all parties involved, HCM proposed an alternate to the original design to provide hand-dug caisson caps around the existing caisson and column construction. Caissons were excavated to depths of 18 feet below the finished floor using reinforced compression rings and shotcrete shoring to reach adequate bedrock.

The above innovations were the optimal solution for this portion of work resulting in another successful hospital project by HCM on budget, on time.

Client: PCL
Location: Hamilton, Ontario

Scarborough Hospital

A Design-Build Solution

The Scarborough Hospital was adding a new Critical Care Centre in the courtyard surrounded on all sides by existing hospital structures.

HC Matcon’s scope of work included:

excavation of the new building foundation on pad footings
permanent shotcrete underpinning system to support surrounding structures
soldier pile and lagging wall to support a pedestrian walkway adjacent to pad footings and service manholes
demolition of service tunnels while maintaining operation and maintenance access for emergency services and hydro caissons to support new canopies and additions to existing structures.

At various points during construction, HC Matcon has been required to provide innovative design-build solutions to accommodate changes to the original design.

Client: EllisDon
Location: Scarborough, Ontario

Centron Business Park Retaining Wall

Steep Slope Retaining Wall

The site topography presented the developer with the challenging task of constructing a permanent retaining wall structure into a hill formation near Blackfoot Trail in southeast Calgary, Alberta. The purpose of the permanent wall was to support a portion of 4th Street S.E. which is serving as an access road to a multi-building complex for commercial real estate. The retaining wall was designed by EBA Engineering Consultants Ltd. as a Cantilever Tangent Wall with various excavation depths, c/w embedment of soldier piles between 7.5m and 14.5m below-grade. The length of shoring wall was 142 linear metres with a total of 470 square metres of exposed surface area. The pile sizes included diameters of 810mm and 912mm. The overall scope of work consisted of drilling approximately 70 soldier piles and 140 filler piles. The client also accepted HCM’s proposal to trim the front surface of the 10 MPa concrete wall which then became more suitable for future application of architectural cladding or finished shotcrete. HCM completed this task with an excavator-mounted Antraquip wall trimmer.

The design also required precision in the placing of the piles along the contour of a curvilinear access road which, in most cases, took place on the edge of a steep slope.

HCM Contractors successfully completed this project to the engineer’s satisfaction, and on schedule.

Client: Centron Group of Companies
Location: Calgary, Alberta

George Street Bridge

This bridge replacement project required the drilling of two abutments consisting of a total of 32 drilled caissons in the existing creek bed. In addition to the environmental concerns related to work being completed in an existing creek bed, access restrictions and overhead lines required the use of a versatile machine capable of drilling the 10-14 foot caissons. The use of an excavator mounted drill enabled the precision drilling required with minimal impact on the surrounding landscape. The equipment’s low headroom capabilities make it ideally suited to projects with headroom constraints and uneven terrain.

Client: Montague Construction Limited

Location: Ingersoll, Ontario