How to Vibrate Concrete Properly

Posted On: 06/20/2019 | Posted by: DY Concrete Pumps

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Is vibrating concrete necessary? Does vibrating concrete make it stronger? If you’re not sure when to use a concrete vibrator or how to vibrate concrete properly for your construction projects, here is all the information you need.

What Is Concrete Vibrating?

Whenever you pour concrete, tiny air bubbles form. Depending on the mix and the pour, there can be thousands of these air bubbles. The more air bubbles you have in your concrete, the weaker its structural integrity when it hardens. A concrete vibrator produces stronger concrete by vigorously shaking the concrete right after you pour it to eliminate the air bubbles.

How Does a Concrete Vibrator Work?

There are different types of concrete vibrators that work in different ways. A formwork vibrator works with precast concrete. You attach form vibrators to the outside of your concrete form so it can vibrate the air bubbles out. Surface vibrators, or jumpers, go directly onto the top of your poured concrete. Suitable for concrete slabs six inches deep or less, this type of vibrator can give you very smooth surface concrete.

Finally, there are internal concrete vibrators, the most common type of concrete vibrator construction professionals work with. If you are using an internal concrete vibrator, you simply push the vibrator into the wet concrete, then slowly withdraw it as it vibrates the material around it.

When using an internal vibrator, it is very important to withdraw the device slowly, or you will not get enough vibration to eliminate the majority of its air bubbles. However, you don’t want to leave the vibrator in the concrete too long as it could cause the water to separate from the cement, hurting the look and structural integrity of the concrete.

The solution is to withdraw the vibrator at the rate of about an inch per second. Start by inserting the head fully, then turning it on and leaving it in place for 10 seconds. Insert it as vertically as possible, so it naturally sinks into the concrete. Then remove one inch each second until it is completely withdrawn. If there are still bubbles coming out once you have fully removed the vibrator, repeat the process until no bubbles emerge.

How Long Do You Need to Vibrate Concrete?

The concrete vibrating process typically takes between 5 to 15 seconds. If there are still bubbles in the concrete when you remove the vibrator, simply repeat the process until there are no bubbles.

Is Vibrating Concrete Necessary?

Vibrating your concrete is almost always recommended since your vibrated concrete will be stronger. But depending on the project, you may have no choice but to vibrate your concrete, as it may be a building code requirement. If you are not planning to vibrate your concrete, you should make sure this will not put you in violation of local building ordinances.

Ordering Concrete Vibrators

If you are looking for a concrete vibrator for your construction project, DY Concrete Pumps can help. We offer reliable Oztec Concrete Vibrators with custom Flexshaft lengths. These concrete vibrators have durable steel heads that produce the highest amplitude and centrifugal force to maximize the radius of influence. To order Oztec concrete vibrators for your project, contact us online now.

-Updated 2/17/2020