Bow Towers Gets the Nod for Canada’s Largest Concrete Pour

What do you get when you add 4 concrete batch plants, 11 pumps, and 95 ready mix trucks? Thirteen thousand cubic meters of concrete and Canada’s largest continuous concrete pour.

Those are the numbers for Inland Concrete Limited’s recent project to supply concrete for the slab foundation of Bow Towers, a high-rise office building under construction in Calgary, Alberta.

Bow Tower is Canada’s first “trussed-tube” skyscraper and will be the tallest single-tenant office tower in western Canada.  Not only was this the largest pour in Canada, but it also ranks third in the world – trailing only the Venetian hotel in Las Vegas and the Al Attar Sky Spiral Project in Dubai.

Named for the Bow River that flows through downtown Calgary,  the project will be completed in 2011 and serve as the new environmentally sustainable headquarters for EnCana, providing space for more than 3,000 employees.

The structure will stand 775 feet high with 59 stories, 22 elevators, three sky gardens, and a six-floor parking garage. It will offer 200,000 square feet of social space for Calgary including a public plaza for shops and leisure facilities.

Inland crews worked 36 hours straight on the project. The foundation slab is 4,600m2 and runs about three meters deep. This is roughly two to three times larger than a typical slab for a shorter skyscraper. The larger slab was necessary to spread the load across a wider area, ensure the foundation settled properly and secure the structure against uplift from wind load. The Bow’s unique shape and the way it reacts to the wind conditions were determining factors in the decision for a larger structural base.

Inland will also supply concrete for the structure’s 60-foot steel columns – to be filled by pumping self consolidating concrete from the bottom up.

Outlook Remains Grim for Housing

Recent economic data reinforces PCA’s outlook for continued declines in housing starts, according to a PCA Flash Report issued today.

Weak economic conditions, tight credit conditions, tepid sales, and high inventories results in projection of a 36% decline in starts for 2008 followed by an additional 1% decline in 2009.

“Despite large home price declines and improved affordability, sales remain sluggish and offer little hope that the inventory glut will be worked off anytime soon,“ says PCA Chief Economist Ed Sullivan. “The economic environment remains weak – reinforcing the concept of a drawn out recovery in housing starts.”

Foreclosures added to the market during 2008 and early 2009 will cause inventory levels to remain in excess of 10 month’s supply during the remainder of the year and not reach desired levels until the second half of 2010.

The residential sector will act as a significant drag on cement consumption during 2008. Cement consumption declined by 11.5 million metric tons in 2007. Three quarters of that decline was attributed to the decline in single-family housing starts. In 2008, PCA expects cement consumption to decline by 12.1 million metric tons, half of which is attributed to continued weakness in single-family construction.
View Flash Report
Contact Ed Sullivan

Concrete Design Standards Discussed at Alliance for Concrete Codes and Standards Meeting

PCA staff from the codes and standards and engineered structures departments met with several allied industry groups recently to discuss the concrete design standards.

The Alliance for Concrete Codes and Standards (ACCS) met on June 17.  Highlights of the meeting included a fire safety presentation and brochure designed to communicate issues to building officials and design professionals.  The Structural Committee is investigating further development of design procedures for one and two-family dwellings.  If it is determined that standardization is needed ACCS may use PCA’s American National Standards Institute (ANSI) accredited process for standards development.

The group also explored the formation of a subcommittee on sustainable development to address provisions of sustainable development standards, which are not currently, but are expected to find their way into building codes.
Contact Steve Szoke

PCA Concrete Technology Advisory Committee Meets

On June 18, PCA’s Codes and Standards Concrete Technology Advisory Council (CTAC) met to address pressing issues including changes to seismic and wind design loads, anchorage to concrete, and specific provisions of the concrete design standards.  The group also discussed difficulties and complexities in meeting new provisions of the design standards.  These were discovered through PCA's Engineered Structures education programs and contact with design professionals and further standards and code development and design examples conducted by the Codes and Standards staff.
Contact Steve Szoke

Salt River Materials Group Named Sloan Award Winner

Salt River Materials Group was named a winner of the 2008 Alfred P. Sloan Award for Business Excellence in Workplace Flexibility. 

The Sloan Awards recognize organizations that are dedicated to making work “work” for both the employer and the employees. Winners of this prestigious award not only offer excellent workplace flexibility practices, but they also use flexibility as a strategic business tool to enhance organizational effectiveness while also benefiting employees.

 “It was easy for us to see the benefits of flexible work policies because of our company culture,” states Roger Smith, president and CEO of Salt River Materials Group. “We believe a work/life balance is important for our employees to be productive, and we can help our employees find that balance through flexibility.”

Applications for the Alfred P. Sloan Awards were open to all organizations in Arizona with more than 10 employees that had been in business for at least one year. Applicants were evaluated in a rigorous two-step process, first comparing the employer’s application to nationally representative data from Families and Work Institute’s National Study of Employers, and then corroborating the employer responses through a survey of employees.

Concrete Gets Warm Reception in Sun Valley: The first U.S. vacation resort, built during the 1930s in Sun Valley, Idaho, hosted the Structural Engineers Association Northwest Annual Conference, June 18-20.  The resort's centerpiece, an alpine lodge built of concrete, witnessed a series of presentations for the 130 people attending.  PCA’s Attila Beres presented a summary of recent code developments.
Contact Attila Beres

Education Foundation Launches Web site:  The Concrete Industry Foundation Inc. was established in 1993 to provide financial assistance to students preparing for careers in the design and construction industry, with special emphasis on study related to concrete. The Foundation provides scholarships and grants for study at the graduate, undergraduate, technical college and apprentice levels to residents of the New York City Metropolitan Area who are studying at accredited schools and programs in the United States.
Visit http://www.concreteindustryfoundation.org/index.html

Registration Now Open for SCC Conference

On-line registration is now available for the Third North American Conference on the Design and Use of Self-Consolidating Concrete (SCC 2008), to be held November 10-12 in Chicago. Leaders from the cement and concrete area, representing industry, academic, and government organizations, will give more than 130 presentations.

The meeting goals are to raise awareness of diverse issues hindering the acceptance and utilization of SCC in the field, transfer knowledge to participants so that they can be better equipped to overcome those barriers, and promote a greater interaction between North American researchers and international users of SCC.

Organized by the Center for Advanced Cement-Based Materials, SCC 2008 sponsors include: BASF The Chemical Company, Lafarge, Axim - Italcementi Group, Euclid, Grace, Portland Cement Association, Schleibinger Geräte, Sika, Federal Highway Administration, American Concrete Institute, Hanley-Wood, Precast/Prestressed Concrete Institute, and RILEM.
For registration and more information, visit www.scc2008.info

Oil Prices Make Concrete More Competitive for Road Building

Rising oil prices are fueling sharp hikes in asphalt costs. Do you think concrete pavement will become competitive with asphalt on a first-cost basis?
> Yes (72.68%)
> No (27.32%)

Notable comments:
“Whether or not we are on a first-cost basis, I believe that life-cycle cost still needs to be the ultimate driver, particularly as both pavement types strive for longer lasting results. Lower maintenance, lower lighting costs, and fuel efficiency savings for vehicles traveling on concrete roads should remain at the forefront of consideration in pavement selection.”

“High oil cost will help make concrete more competitive but the real challenge is competing against under-designed asphalt.”

“No, there are too many other considerations such as asphalt is quieter and quicker to install. Nobody seems to think about the fact that it doesn’t last as long.”

“There have already been two highway projects in Pennsylvania that went to the concrete bid because it was lower than asphalt’s first cost.”

“It has already received the interest of pavement designers here in Texas. This and the rising cost of reinforcing steel has gotten the designers to take a closer look at non-reinforced roadways. Reports are the cost of concrete paving has become VERY competitive.”

“I believe concrete will become competitive; however politics will not allow concrete to flourish in road construction.”
Take this week's poll