precast concrete

When you enter the world of precast concrete, you start to hear a lot of talk about strength and reinforcing. Since one of the main benefits of using precast concrete walls is how strong and durable it is, we want to share with you how to reinforce concrete walls and make them stronger.

Compressive vs. Tensile Strength

In order to understand how to reinforce concrete walls, you have to understand concrete’s different kinds of strengths first. Compressive strength is how strong the concrete is when you squeeze the concrete. Tensile strength is how strong it is when you try to stretch concrete. Concrete, especially when it is made well, does really well under compressive stress.

Where concrete struggles is with the tensile strength – this is what reinforcing concrete is trying to increase. Without reinforcement, the tensile strength of precast concrete is typically about a tenth of its compressive strength.

Change the Concrete Mix

Concrete is usually a mixture of cement, water, and aggregates like sand or gravel. Changing the amounts of each part will impact different properties, e.g., increasing the water will make the concrete more fluid. Adjusting the mixture like this can also have negative consequences, e.g., increasing the water will also decrease the final strength of the concrete.

So, you could increase the strength of concrete by increasing the amount of cement in the mixture, but it isn’t the best or most efficient way to do it. The increase in strength wouldn’t be enough, so you would still have to do more to get the tensile strength where you need it to be.

Add in Rebar or Mesh

Steel rebar or mesh has a much higher tensile strength than concrete. Rebar is often added to the concrete to increase the tensile strength by transferring that tensile stress from the concrete to the rebar. The rebar bears that load. This is one of the most common methods for reinforcing precast concrete.

The steel rebar is placed at specific intervals – determined by an engineer. The steel rebar must be placed at the precise required spacing. Trying to cut corners by increasing the spacing could spell disaster for your precast concrete wall later on.

The size of the steel reinforcing rebar is also incredibly important. We advise you don’t try to save a buck by getting a smaller size. You will probably end up regretting it.

The skill of the person installing the rebar is a significant factor in the quality of the end product. There are a lot of things to consider. The rebar has to be cut and bent just right. The spacing of the rebar – not just from each other but also from the walls of the precast concrete form – has to be exact. Even pouring the concrete has to be well thought out. Any gaps or voids around the rebar will lower the quality of the end product.

At the end of the day, one of the easiest ways to increase the strength of your precast concrete wall is by going with a company that does things right. Well made concrete will always outperform concrete made by someone who cuts corners.

American Precast Concrete Inc.

Precast concrete is one of the most durable and beautiful materials that you can use for your next fencing project. If you would like to learn more about American Precast Concrete’s products, please contact us. We would be happy to answer any questions and help you find the products that are right for you.