On this day in 1976, when the CN Tower in Toronto opened it was the world’s tallest free-standing structure; a record it held record until 2010. In 1995, the American Society of Civil Engineers declared the tower to be one of the Seven Wonders of the Modern World.
The tower, now owned by the Canada Lands Company (2013), was built by pouring concrete onto a slip form that moved upward an average of 22 feet a day. For 40 months, working Monday to Friday each week, 40,425 cubic metres of concrete, enough concrete to build a sidewalk from Toronto to Kingston was poured. The horizontal lines you can see in the concrete are nicknamed “Friday lines” because that indicates where pouring stopped at the end of each week.
Today in Canada, the cement and concrete industry employs nearly 27,000 people in the production and distribution of cement, concrete and concrete construction materials (Cement Association of Canada, 2013). This industry generates more than $8 billion in annual sales, which contributes $2.9 billion to the country’s Gross Domestic Product. You can be sure you will learn about this industry if you are enrolled in any of the Engineering Technology programs. To find out what resources we have to support these programs, have a look at these subject guides.
Canada Lands Company. (2013). CN Tower general information. Retrieved from http://www.cntower.ca/en-CA/Media-Centre/Press-Kit.html