Dealing With Reinforced Concrete Slabs

Although concrete is a relatively strong material in its own right, its low tensile strength means that it often benefits from reinforcement. Adding a framework of reinforcement bars (or rebar, for short) in a concrete structure can help it last for a long time. Unfortunately, this can add a slight wrinkle to your demolition plans, since you'll have to figure out how to quickly and efficiently break down the rebar along with the concrete. The following explains how to quickly break down reinforced concrete.

Dealing With a Mesh Grid

It's not unusual for a concrete slab to use wire mesh as reinforcement instead of whole rebar, especially if the slab itself was designed to be relatively thin (less than 4 inches in thickness, in most cases). Fortunately, wire mesh grids are usually easier to deal with than their rebar counterparts when it comes to removal. You'll need a pair of bolt cutters to cut through the thick wire fabric. If you're dealing with much thinner wire (such as 10 gauge wire), you'll only need a pair of side cutting pliers.

Once you've exposed the wire mesh on the concrete slab, use your bolt cutters or side cutting pliers to snip through each wire holding the concrete chunks in place. Cut up the wire mesh as you go instead of waiting until the end to finish the job. This way, you'll save plenty of time and effort as you break up the reinforced slab.

Dealing With Rebar

When it comes to dealing with actual rebar, you'll need something a bit more substantial than bolt cutters to cut through the thick steel bars. Rebar comes in a wide variety of thicknesses, making the above tools a non-starter for cutting the structural material apart. Instead, you'll need a reciprocating saw equipped with a hacksaw-tooth pattern metal cutting blade to cut through the rebar.

As you make your cut, make sure to not bend the blade, as this can prematurely break it and possibly cause a safety hazard for yourself and others in the area. You'll also want to use high-quality blades for this job, as less expensive blades can break multiple times before the job is complete.

If you don't have a reciprocating saw, an angle grinder with a metal cutoff wheel may also do the trick. Mount the cutoff wheel and hold the grinder securely, making sure it's far away from your face as possible. Don't force the wheel through the rebar -- instead, slowly drop the wheel onto the rebar and let the tool's weight and the cutting action of the attached cutoff wheel do the work. Your speed greatly depends on the thickness of the rebar, as well as the amount of rebar you need to cut through.

For dealing with large amounts of rebar, you might want to consider using a plasma or oxyacetylene torch as your cutting instrument.

Can You Recycle the Rebar?

After breaking up a reinforced concrete slab, chances are you'll be left with a bunch of concrete rubble and a bunch of cut rebar. Fortunately, steel rebar can be readily recycled as long as it's thoroughly liberated from the concrete and, in some cases, relatively intact. Cut and heavily bent lengths of rebar can be melted down and reused in a wide array of other products, while whole sections of rebar can be recovered and reused in a wide variety of nonstructural work.

Breaking down a concrete slab already involves plenty of hard work, but the above tips can help you save time and effort when dealing with slabs that have sizable amounts of rebar or wire mesh inside. If the job is too large for you to handle on your own, consider contacting a company like Garrett Concrete Cutting, Coring & Sawing Inc - Chino for assistance.