How to Determine the Tensile Strength of Concrete

Posted on December 15, 2018

Have you ever wondered how to determine the tensile strength of concrete? What is tensile strength and why does it matter in your next project? It’s actually a very important part of the concrete’s overall structural strength and stability, providing a firm foundation for whatever you’re going to place on top of it, whether it’s a swimming pool for backyard enjoyment, a patio you want to stay level for the next decade or so or a huge skyscraper that will dominate the skyline for miles. Here’s a look at what tensile strength is, why it’s important and how you can determine the tensile strength of the concrete in your next project.

How to Determine the Tensile Strength of Concrete

What is tensile strength?

Generally speaking, the tensile strength of any material is its ability and strength against stretching or breaking when being pulled apart. But when most people think about concrete installations, they think about slabs and driveways. Why would you need to worry about those kinds of projects being pulled apart? As the earth moves and shifts, the concrete is often pulled in different directions. If it doesn’t have appropriate reinforcement and tensile strength, the concrete can crack and pull apart, leaving unsightly and dangerous gaps in sidewalks, driveways, slabs and other structures.

This is different than compressive strength. When someone refers to a 3,000 or 5,000 PSI concrete, they’re usually referring to how much weight it can bear. Because tensile strength tends to be much lower, materials such as rebar and reinforcing mesh are used to prevent the concrete from spreading apart. This helps provide a structure that bears the strain of the tensile strength in place of the concrete.

How do you determine the tensile strength of concrete?

There are different ways of testing concrete. One of the ones that is most commonly considered when concrete testing is brought up is what’s referred to as a slump test. This measures how much the concrete deforms when wet. Concrete that deforms too much often has too high of water content, which weakens the concrete. Though a poor slump test can be an indicator of poor tensile strength, it’s typically used more often for measuring compressive strength.

The American Concrete Institute has extensive documentation available on a wide range of testing methods. To test tensile strength, there are several different tests that can be performed. The first is a flexure test, which tests how much motion the concrete can take before it breaks. The second places direct tension on the concrete, while the third tests for splitting while the concrete is under pressure.

By having a solid grasp of what tensile strength is and how to determine the tensile strength of concrete, you can gain a much better appreciation for the strength this hard-working material needs to get the job done. But once you’ve decided what strength of concrete you need for your project, have you considered what tools you’ll need? At BN Products, we have a wide range of tools available to help make your next concrete or cement project go much more smoothly and easily. Why not take a look at what we have available for your next job?