STRUCTURES
Glass skywalk in the Rockies
By: Nordahl Flakstad
Despite efforts to make it non-intrusive, the newly completed Glacier Skywalk observation deck, near the Columbia Icefields in Alberta’s Jasper National Park, seems destined for more than a mere walk-on part once tourists start arriving in May.
Simon Brown, of the lead design firm, Read Jones Christoffersen (RJC), and others involved with the design of the cantilevered glass walkway 150 metres above the Sunwapta Valley, began work in 2010. The chosen site is near a pull-off on the Jasper-Banff Icefields Parkway, six kilometres north of the existing Icefields Discovery Centre.
The design entailed some challenges – not least of which was the walkway’s glass floor, supported on a structural steel skeleton. The idea of a see-through walkway that allows visitors to look vertically down a precipice is not unique. It is employed on Arizona’s Grand Canyon Skywalk opened in 2007, for example. However, below that structure’s floor there are two large box girders, which limit the vertical sightline straight down into the canyon to one third of the walkway.
In contrast, along the entire length of the 30-metre parabolic deck of the Glacier Skyway, visitors will be able to look straight down. Brown explains that a draped cable, a critical structural element on the inside radius of the curved deck, facilitates this unobstructed view.
The walkway’s outermost point is 35 metres from the rock face. It is supported on cantilevered, trapezoidal box girders, secured onto footings rock-anchored some 30 metres into the mountain. Regarding the cantilevered structure, Brown notes, “We had a very large reaction to deal with where it ties into the cliff. A precise understanding of the rock formation and quality was required.” Beyond the weathered surface material, the deeper rock generally was solid, and where there was cracking it was factored into the design.
The deck encounters vibration from two main sources – those walking on it and ambient winds. The first was addressed by tuned mass dampers in the walkway. Following wind-tunnel testing by RWDI of Guelph, the response to crosswinds in the valley was addressed using wind deflectors attached to the outer handrails. The glass floor is fashioned from laminated, tempered and heat-strengthened glass, designed by RJC’s Toronto office.
The Skywalk received a Future Projects Category Award at the World Architectural Festival in Barcelona, Spain, in 2011.
The design team is: RJC ( lead design firm and structural engineers), Sturgess Architecture (architects), PCL (project lead and general contractor), Thurber Engineering (geotechnical), Golder Associates (environmental), Urban Systems (civil), RWDI (wind) and SMP (electrical).
CONFERENCE
ASHRAE going residential?
The 2014 ASHRAE Conference held in snowy New York City on January 18-23 included an array of technical and educational sessions. Topics ranged from arcane subjects like “RP-1353 Stability and Accuracy of VAV Box Control at Low Flows Rendezvous Trianon,” to the broader “Data Center Control and Fire Safety in Tall Buildings,” or “Engineering Ethics: A Case Study Analysis.”
ASHRAE’s 2013-2014 president, William P. Bahnfleth, P.E., told the media that the organization has three main initiatives.
First, a committee has been formed to focus on improving indoor air quality. Bahnfleth said that over the last 30 years we have made huge progress in energy efficiency, but we also need to increase progress in creating healthy indoor environments. He noted, for example, that there needs to be more communication between the scientists who do testing, and engineers who understand building physics.
A second committee is looking into expanding ASHRAE’s work in developing economies such as China, India and in South America.
A third new committee is considering ASHRAE becoming more involved in the residential market. Historically the society has concentrated on the commercial and institutional sectors, so this represents a big change.
The association of 54,000 engineers and others involved in building systems and technologies is clearly expanding its horizons beyond its traditional base and 1894 origins. Perhaps most telling is the decision to drop the former descriptive title “American Society for Heating, Refrigerating and Air Conditioning Engineers” in favour of using only the more generic and internationally-friendly acronym.
Once attendees had enough learning in the classroom, they could take a technical tour into the bowels of New York iconic buildings such as the Rockefeller Centre to see its district cooling plant, or One Penn Plaza to consider its cogeneration plant. Or they could join a general tour, such as the large group that went by subway train to Ground Zero and saw the somber monument to the event that changed the world.
awards
Windsor CSO one
of largest in world
Stantec won the Project of the Year award from the Ontario Public Works Association for the City of Windsor’s Riverfront Retention Treatment Basin collection and treatment system.
Considered to be the first and largest of its kind in the world, the facility manages the combined sewer overflows from the old riverfront district into the Detroit River. It fulfils a major part of the city’s pollution control plan.
The project earned the award in the “Environment – greater than $50 million” category at the OPWA annual conference on January 30 in Mississauga, Ontario.
Led by Tony Berardi, P. Eng., Stantec was prime consultant and helped guide the project through a long environmental assessment process, provided the construction drawings and oversaw construction.
This is the project’s second major award. In April 2013, it won the “Most Outstanding Project for engineering firms with 351+ employees” award from Consulting Engineers of Ontario.
TRANSPORTATION
Canada builds historic first road to the Arctic
In early January, Prime Minister Stephen Harper was in the Far North for the official groundbreaking of the first permanent highway to reach Canada’s Arctic coast.
The all-season 138-km road stretches from the Dempster Highway (NWT Highway 8) at the town of Inuvik just above the Arctic Circle, northeast to the hamlet of Tuktoyaktuk on the shore of the Arctic Ocean near the Mackenzie River Delta.
Envisioned since the 1950s, the highway will ease access to oil and gas exploration operations in the Beaufort Sea and help establish Canada’s sovereignty over the Western Arctic region.
Approximately 70 kilometres of the road is on Inuvialuit lands. The federal government is providing $200 million of the $300-million cost of the road’s construction.
EGT-Northwind, a joint venture of E. Gruben Transport and Northwind Industries, won the $229-million contract to engineer and build the highway for the NWT Department of Transportation. In order to protect the permafrost, the two-lane gravel roadway will be built on top of a geotextile fabric. Construction will take place primarily in the winter months, also to protect the permafrost, with completion by 2018. The road will be 8 to 9 metres wide with 3:1 side slopes.
Another, longer, stretch of all-weather highway to run northwest from Wrigley to Dempster and Inuvik along the Mackenzie Valley is currently undergoing an environmental assessment.
COMPANieS
AMEC to buy Foster Wheeler
International engineering giant AMEC, based in the U.K., but with approximately 6,500 employees and 60 offices across Canada, has announced a provisional agreement to buy Foster Wheeler AG. Foster Wheeler is an international, Swiss-based engineering company described as a historic “rival” to AMEC by Reuters. Both companies are heavily involved in the oil and gas, mining and en
ergy sectors, as well as other areas like infrastructure and environmental services. AMEC has 29,000 people in 40 countries worldwide, and Foster Wheeler has 13,000 people in 30 countries. Foster Wheeler had agreed not to solicit alternative proposals until 22 February.
Williams Engineering Canada has opened an office in Victoria, continuing the expansion of the Edmonton-based company into B.C. The new office is led by Steve Woodmass, B.C. regional director, and managed by Collin Cronkhite.
Focus Corporation has acquired Hunter Laird Engineering based in New Westminster, B.C. Hunter Laird is a civil engineering and planning consulting practice with its origins dating back to 1964. It will now operate as Hunter Laird, A Focus Company.
Ben Almond, P.Eng. is the new regional market manager for CH2M HILL’s water services team for Canada, based in Calgary. He was previously project delivery manager for the firm’s energy market.
R.V. Anderson Associates announced two new senior associates in January: Bruce Buchanan of Moncton, N.B. and Vince Grande of Niagara, Ontario.
SNC-Lavalin in partnership with Cementation Canada, the Morris Group, Flying Post, Lac Seul, Mattagami and Wahgoshig First Nations, has signed a memorandum of understanding to capitalize the First Nations Mining Corporation (FNMC). FNMC will form joint venture partnerships with local Aboriginal communities to do projects for mining companies in Ontario.
PROFESSIONAL
University of Waterloo launches green energy diploma
Canada’s largest engineering school is launching the country’s first graduate diploma in green energy studies. The University of Waterloo Faculty of Engineering’s Green Energy Graduate Diploma is an online program intended to provide professional development for working engineers.
The program will cover green energy systems such as bioenergy, fuel cells, air pollution and greenhouse gas management, solar and wind energy, as well as building energy performance. Contact greendiploma@uwaterloo.ca.
Buildings
Fix the housing crunch
The Federation of Canadian Municipalities is pushing hard for the federal and provincial governments to invest in capital repairs to social housing. The FCM’s campaign,”Fixing Canada’s Housing Crunch,” has been supported by 140 council resolutions, while cities like Halifax and Toronto held public roundtables in January. The concern is that the federal government has no long term plan for funding this sector.
HIGHWAYS
South Fraser Perimeter Road complete
The last phase of the $1.26-billion South Fraser Perimeter Road (Highway 17) was opened in Delta, B.C. in December. Part of the Asia-Pacific corridor, the four-lane expressway runs along the south bank of the Fraser River, connecting the Tsawwassen Ferry Terminal in southwest Delta to 176 Street in North Surrey, and with connections to the Golden Ears Bridge and other river crossings.
The project involved construction of 15 overpasses, three interchanges, and major environmental restoration work.
Fraser Transportation Group was the design-builder and will operate the highway for 20 years. FTG includes ACS Infrastructure, Ledcor and Dragados Canada, among others.
