Oil Extraction using DSI Technology: Oilsands Project in Alberta, Canada
The city of Fort McMurray, in the Canadian province of Alberta, is located in the Athabasca Oilsands area, at the center of the country’s oil producing region. According to expert estimates, the province’s oilsands deposits cover approximately one fourth of Canada’s oil consumption. Oilsands are a mixture of bitumen, sand and water and for the most part are mined using the open pit mining method.
The oil producer Suncor, one of the largest Canadian companies in this market, is currently building a new upgrading facility. The Voyageur project will increase crude oil production by 200,000 barrels per day to 550,000 barrels per day.
The facility consists of three coke drum pairs, the framework of which is supported on castin place concrete foundations. Due to their large cross sections, the coker columns are heavily reinforced because they have to resist large forces during operation. Inside the coker facility, bitumen is split into its chemical components.
Because they are easy to splice during installation, the engineer decided to use DYWIDAG bars as reinforcement for the concrete structure and the foundations. Approximately 390t of 63mm Ø DYWIDAG bars with a yield strength of 552 MPa/80 ksi were used for this project.
Due to the large diameter of the bars and their high load bearing capacity, the total quantity of vertical reinforcement bars were reduced and the clear space between individual reinforcement bars was increased. Consequently, a congestion of reinforcement elements at the intersections was avoided. Thanks to the couplers, the DYWIDAG Bars were installed easily and quickly at their respective locations, and a complicated threading of the bars through the vertical reinforcement structure could be avoided.
What made the project challenging was the fact that the DYWIDAG Bars had to be precisely positioned because the reinforcing steel cages did not have any allowance for adjustment once completed. The exact positioning of the DYWIDAG Bars was necessary so that the bars could be connected to each other through couplers to link the completed cages.
The DYWIDAG Bars were anchored in the pile cap with plate end anchorages. All anchor plates were combined into one anchor frame in order to facilitate placement and stabilization of the bars during the construction of the pile cap. At the upper end of the columns, forces had to be transferred from the vertical column reinforcement to the horizontal reinforcement of the slab.
This is usually achieved by bending the reinforcement. However, the large diameter of the bars made bending them impractical. Consequently, a transfer frame was installed at the bottom of the top slab into which the large DYWIDAG bars were anchored with plate anchorages. In addition, four #8, 25mm Ø DYWIDAG Bars with a yield strength of 517 MPa / 75 ksi were integrated into the frame construction for each 63mm bar. A total of approximately 40t of #8, 25mm Ø DYWIDAG Bars were supplied. These bars were extended up through the slab and bent to overlap with the horizontal top slab reinforcement.
DSI Canada is pleased that DYWIDAG Reinforcement Systems were used for this unconventional project.