February 25, 2013

Cement association president sings the praises of concrete

CONCRETE FEATURE

JEAN SORENSEN

correspondent

The Cement Association of Canada (CAC) is facing a tough battle in B.C. as its whirlwind Canadian campaign, Rediscover Concrete, tries to convince municipalities to use more concrete in buildings and highways.

About 44 B.C. municipalities have adopted wood-first policy and bylaws. The province has few concrete roadways.

“Government shouldn’t pick the winners and losers in the economy,” said Michael McSweeney, CAC executive director, responding to the wood-first movement.

Material choices should be left to professions, insurance companies and firefighters, said McSweeney, who held 162 meetings in 162 days with mayors, city council administrators, engineers and architects nationwide, including B.C. and Alberta.

He plans to return in the spring.

B.C.’s 2009 Wood First Act promotes wood in provincially funded buildings. Nova Scotia and New Brunswick have followed suit. Halifax’s proposed policy has drawn criticism from the CAC.

The B.C. Chamber of Commerce has also recently voiced concerns regarding B.C.’s wood first policy.

Despite wood-first policies, McSweeney said, B.C. hasn’t made significant inroads into highrise wood construction.

“I always say that government should not rob Peter to pay Paul,” said McSweeney.

Ready-mix plants exist in almost every town in B.C.

Wood WORKS! executive director Mary Tracey said wood is environmentally friendly and sequesters carbon until burnt or decomposed.

Her organization also advocates for the best building material in a given situation.

She said the province was expected to make an announcement in the near future regarding a tall wood building.

Currently, the newly-completed, five-storey Earth Sciences Building at UBC is the largest use of mass timber construction in North America.

McSweeney is promoting two major concepts in his tour.

The first is Contempra, a new cement whose manufacturing process cuts greenhouse gases by 10 per cent.

“It has all the properties of normal cement and meets the provincial and national building codes,” he said, adding he would like to see governments mandate its use in government-funded buildings.

A second pillar of McSweeney’s campaign is that comparative costs between concrete and other materials should be on a lifecycle basis.

“A building made of concrete lasts hundreds of years and wood typically 75 years,” he said.

Costing should include energy operating costs as concrete’s thermal mass can yield savings of 8 per cent.

McSweeney makes a similar argument for concrete roads.

“Concrete pavement can last for 35-50 years while asphalt is seven to 12 years typically,” he said, adding the asphalt costs triple over concrete’s lifecycle although concrete has a higher front-end cost. Concrete also stands up to heavy-load vehicles and is not prone to “shoving” (waves as vehicle tires push into sun-warmed asphalt).

“Municipalities should let the voters decide,” he said.

McSweeney said the CAC is working with the B.C. Ministry of Transportation on several trial projects. However, concrete highways have had mixed reviews in B.C.

Winvan Paving vice-president Franco Pastro said concrete highways take up to 30 days to cure to full strength.

“With asphalt, you can drive on it the next day – or even that evening,” he said.

Concrete U.S. interstate highways exist, he said, because they are wide and one lane can be shut down and still facilitate traffic flow.

Cewe Paving senior estimator Gerry Kilik said roller compressed concrete (RCC) was the closest example of highway concrete paving in B.C.

Cewe, which specializes in RCC, used the application about a decade ago on a down slope between Horsefly and Likely, B.C., where heavy truck braking was causing road damage.

The stretch needed repairs every two or three years. RCC was used as a sub-base with an asphalt top for smoothness.

Kilik said the section has stood up well.

“RCC is a very dry mixture of concrete,” said, adding it is placed eight to 12 inches deep.

The mainstream application of RCC is port areas, parkades and airport runways.

Burnaby roads superintendent Erik Schmidt said Gaglardi Way leading to SFU was paved in concrete in the 1970s or 1980s.

It didn’t stand up to sloped conditions and was later re-paved with asphalt.

Schmidt said his city has some post-WWII stretches on major thru-ways where the curb and turning lane were formed from concrete.

They have stood up well over the years, he said.

Schmidt questioned using concrete on residential roads, as crews often need to access underground utilities.

“It’s a shame to tear up a concrete road,” said Schmidt.

Jack Davidson, president of the B.C. Road Builders and Heavy Construction Association said his members are capable.

“If the provincial government decides that concrete roads are more effective, then we would work with them,” he said.

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