No matter how much wishing and hoping we do, one unfortunate fact of life is this: concrete cracks. It’s a shame, really.
Cracks are bad for a variety of reasons, such as the threat of moisture seeping in and reduced strength. Plus, it just looks bad. Fortunately, there are ways to limit this pesky truth, and one of the best ways is by prestressing the concrete.
With prestressed concrete, initial compression is applied to the concrete before ever being exposed to an external load. This initial compression is introduced by high-strength steel wire located in the concrete section.
High-strength steel tendons are placed between two abutments and stretched to 70 to 80 percent of their ultimate strength. Concrete is poured into molds around the tendons and allowed to cure.
Applying the initial compression allows the concrete to better handle the external loads, particularly in large, long-spanning projects such as bridges, tall buildings, gymnasiums, and parking garages.
Using prestressed concrete benefits designers and builders, as it allows for lighter and shallower concrete structures without compromising strength.
How Does Prestressed Concrete Work?
Ok, so how does this work? Good question.
Think of a row of books on a bookshelf. If you wanted to move those books all at once, ample pressure needs to be applied to both ends so the books all move together. Once lifted from the bookshelf, the pressure applied before the lift is sufficient to keep the books from falling downward due to gravity.
With concrete, the pretension applied before being subject to external loads helps improve the concrete’s bendability and structural flexibility, which helps avoid cracks.
Prestressed concrete has greater shear strength and fatigue resistance, making it the ideal choice for sleek and/or slender structures.
Need More Info? Contact Us!
Before you start your next project, consider using prestressed concrete as a way of providing strength and stability, all while reducing the risk of cracks! Contact us today to learn more or discuss your project.