Hamilton Mountain Trunk Storm Sewer Rehabilitation
Recently, Dufferin Concrete was called upon to provide about 2,000 cubic metres of concrete to help prevent the collapse of an essential utility we often don’t think twice about—one of the City of Hamilton’s storm sewers.
The Hamilton Storm Sewer is a large cast-in place concrete arch box sewer that extends for several kilometres and contains two active sanitary sewers encased in concrete curbs. The infrastructure dates back to the 1970’s and over the years, the rock mass has been squeezing the sewer, causing extensive cracking of the storm sewer roof, walls and floor slab. Due to this extensive damage, about 600 metres of the sewer needed to be reinforced—and quickly—as it had tenuous structural stability. The rehabilitation project included the construction of an access shaft, as well as the removal of a section of existing storm sewer roof to facilitate working access to the sewer.
Our customer, Technicore Underground Inc. was mandated with the completion of this project. For its part, Dufferin Concrete provided a cost-effective semi-self-compacting concrete solution incorporating a specialty plasticizer, a viscosity modifying admixture and a shrinkage reducing admixture.
By working together with our customer, Dufferin Concrete was able to provide a concrete solution that facilitated the construction process while keeping the project on budget, in addition to contributing to the lowering of repair costs related to surface defects and honeycombing.
Eglinton Crosstown Light Rail Train Project
The Eglinton Crosstown Light Rail Transit (LRT) project is one of many ongoing Metrolinx projects aimed at connecting Toronto area communities and enhancing mobility in the region. This project was awarded to Crosslinx Transit Solutions for $8.5 billion. Dufferin Concrete provided 300,000 cubic metres representing approximately $50 million of the contract value. Including 25 stations, […]
A specialized mix and a strict pour schedule for the TTC
Working alongside Buttcon, Dufferin Concrete completed a job for the Toronto Transit Commission (TTC) on the Patten Building, providing not only innovative products, but ensuring quality service and technical support.
Having worked with the TTC on numerous occasions, our team is familiar with their requirements on schedule dates, health and safety, security controls and of course quality products and services. During construction, the building remained completely functional with the exception of the ground parking level, where the new concrete reinforcement was added. Due to the reduced working area and limited space to delimit a construction zone, all concrete pours were scheduled for Saturdays, leaving no room for error.
Our team worked to design a completely new Self Consolidated Concrete (SCC) mix that would meet the TTC’s strict specifications. The concrete was pumped from an offsite location across from the job site and had to flow through the forms between two layers of rebar and stir-ups. The complex formwork needed to remain completely water tight and valves and ports were installed to release air and eliminate air pockets. As an extra measure of care, camera ports were added to confirm that all voids were filled. There were three scheduled days to complete the six phases of the pour in a designed sequence in order to reduce the stress of the structure and possibility of voids. The largest of these phases was 50+/-m3. Two testing companies, comprising of 35 testers and monitors, were on site to perform several tests on each load of SCC going into the pour. The compressive strength was achieved on average three to five days after pouring. TTC and Buttcon were pleased with the technical support as well as the excellent quality of the concrete, workability, uniformity and performance of the SCC mix supplied by Dufferin Concrete and have indicated that this would be a preferred mix for future similar TTC projects.
Mid-Halton Wastewater Treatment Plant
To meet increased demand and continue to protect the water of Lake Ontario, the Regional Municipality of Halton had to address the need to increase capacity at the Mid-Halton Wastewater Treatment Plant in Oakville Ontario from 75 million litres per day to 125 million litres per day. The project will not only provide environmental benefits to Lake Ontario, but will also improve the safe handling and management of wastewater as our communities continue to grow.
The project, valued at $79 million began in 2014 when Strabag Inc., the construction contractor was awarded the job and began production. For this project, a 3.6m diameter Tunnel Boring Machine (TBM) was required to excavate through layers of shale and limestone starting from the QEW under Third Line in Oakville into the lake. The project includes a 6.3Km underground pipe in two stretches; The onshore stretch spanning 4.2 km from the wastewater treatment plant on North Service Road to Lake Ontario, 60m below the roads surface, and an additional 2.1km offshore stretch ranging from 15 m to 50 m beneath the bedrock of Lake Ontario for a total length of 6.3km.
Dufferin Concrete designed a specialty concrete mix to endure a four hour lifespan and be delivered by rail inside the tunnel. Our team also used wet Shotcrete to secure and shape the tunnel’s rounded profile. Dufferin Concrete provided approximately 25,000m3 meters of concrete used in the project.
Pemberton Group U Condo
Located in downtown Toronto in the heart of Canada’s financial district, the Pemberton Group’s U Condo project consisted of two condominium buildings, 45 and 55 stories, encompassed by 28 townhomes. Though there are hundreds of similar condominium projects across the city, this one presented some unique challenges that the Dufferin Concrete (DC) team was eager to tackle.
“For starters, with a location in the heart of the city surrounded by residential and commercial buildings, a major university and various other schools, churches and a surplus of one-way streets, the site was a logistical dilemma. We had to work closely with the developer and the city to ensure we could get the job done safely and efficiently,” said Karl Rammler, District Manager, Dufferin Concrete.
One Day, One Pour
Beyond the complexities of the development’s location, the project required a very strict pour schedule and concrete mix. The strict time frame due to traffic closures and the technical requirements of the slab meant the 2200 cubic meters of concrete for the foundation of the first building had to be poured in one day. The design included a mass “raft” or foundation slab, requiring a very strict pouring timeline to control the temperature of the concrete core.
“Dufferin Concrete was chosen because of the level of expertise they bring to the table. This was a challenging project logistically on a busy street in downtown Toronto with a tight time constraint and very specific concrete mix. We knew we could count on Dufferin to get the job done right, doing it in a professional manner and ensuring minimal disruption to the local community,” said Eliot Muzzo, President, The Pemberton Group.
A Memorable Project
On a chilly spring Saturday in Toronto, Dufferin Concrete crews across the city were in action before dawn for the pour. With road closure permits in place, police on site to direct traffic and keep the public safe, and over 120 DC employees scheduled to work, the team was ready to deliver a flawless pour.
Concrete was provided from three separate mixing plants in the city to ensure a continuous supply with a fourth plant on standby in case any unforeseen circumstances halted production at any of the primary plants.
“The energy on site was really great. The drivers were excited to be a part of such a memorable project, and the team came together to ensure that safety was top of mind for everyone and the job was being done right. I’m incredibly proud of everyone for their hard work,” said Peter Moylan, General Manager, Dufferin Concrete.
A few months later, it happened all over again when the foundation for the second building was poured, this time requiring 2700 cubic meters of concrete, once again in a memorable one-day pour.
Paradigm Condominiums Burlington
The development of the Paradigm Condominiums began in August 2015 by the Molinaro Group in mid-town Burlington. The three buildings, made up of a center tower, east tower and west tower will be 20 stories, 23 stories and 20 stories tall respectively. The first two towers were commenced prior to the third tower in order to facilitate the construction schedule and allow residents to move into a completed community with minimal construction activity from adjacent towers post move-in. The three buildings are scheduled to open in 2018.
These elegant scaled buildings offer many value added features with the exterior amenities, underground parking and the close proximity to the Go Transit. Dufferin Concrete provided over 40,000 m3 of concrete ranging up to 80mpa in strength to build this magnificent property.
A raft slab containing 600m3 of concrete was suspended three stories in the air connecting two of the condominiums. Due to the close proximity of the Go train, there was a concrete reinforcing wall built at the back of the building. This was built to ensure the safety of the people and the structures in the event of a train derailment. The concrete wall is built to absorb the impact of the train so that no person in the building would be injured.
The project’s commitment to sustainability is another feature that makes Dufferin Concrete a proud partner on this Molinaro Group development.
Paradigm’s highly-reflective “white” roof reduces cooling requirements during the summer months, and lessens the heat island effect typically enhanced by metropolitan high rises. The development includes a Construction Waste Management Plan that minimizes waste sent to landfills, and redirects recyclable resources back to the manufacturing process. Building materials were sourced locally, including concrete for Dufferin Concrete West district, in order to reduce the environmental impacts of transportation. The project is slated to seek LEED® certification.
Sir Adam Beck Niagara Tunnel
The 10.4 kilometer tunnel below the city of Niagara Falls diverts water flowing at 500 cubic meters per second from going over the Falls, down the length of the tunnel to the Sir Adam Beck power station. There, clean hydroelectricity is generated to power 160,000 homes in Ontario for 100 years. Strabag, the primary contractor for the Niagara Tunnel project, engaged Dufferin Construction on the project and Dufferin Concrete to provide the innovative concrete solutions for the entire project – the cast-in-place tunnel liner and all concrete outside the tunnel. This is enough concrete to pave a two-lane highway for 160 km.
Frank Stancati, Dufferin Concrete’s Project Supervisor at the tunnel, said the biggest difference with this project is the sheer volume of concrete produced and delivered 24 hours a day, seven days a week. “We didn’t go down into the tunnel at all. Our job was to deliver around 800 cubic meters of concrete every day, to exact mix specifications, without fail. The concrete was then pumped down the tunnel where specially-built Strabag mixers took it to where it was needed.
Our team made two very different types of concrete for the tunnel. ‘Shotcrete’ was sprayed onto the tunnel walls immediately after Big Becky, the boring machine, passed. This stabilized the rock to provide temporary support for the tunnel wall until the liner concrete was cast.
“This was the most sophisticated concrete solution in Ontario at the time,” said Peter Moylan, General Manager of Dufferin Concrete . “The design mixes were unique. We were making cast-in-place concrete that had to set quickly and cannot shrink, creep, or crack. It also had to be wear-resistant to last a century. And it had to be pumped over great distances without losing its characteristics at the other end, something neither Dufferin nor Strabag has ever done before.”
Some of the major work completed by Dufferin Construction and Dufferin Concrete included:
• Blasting out and excavating the 43-meter deep, 450-meter long outlet cut. This is where the water will come out after flowing through the 10.4-kilometer length of the tunnel.
• Blasting out and excavating the inlet near the Falls – a 37-meter drop with a 50-degree slope over 150 meters.
• Building the accelerator wall out in the Niagara River which will funnel and accelerate the flow of water to the tunnel.
• Building a cofferdam around the inlet to keep it dry for construction and for Big Becky to come out.
• Creating a two-kilometer long ‘island’ of material drilled out of the tunnel.
Dufferin Concrete Head Office
2300 Steeles Ave. West, 4th floor
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