Our lineup of concrete vibrator rental options guarantees that your concrete will be stable once it cures, with no bubbles or cracks. United Rentals offers multiple models and sizes of concrete vibrator machines, including backpack concrete vibrators and small cement vibrators for portability and convenience.
Our flex shaft concrete vibrators are ideal for driveways, small slabs, columns and foundation walls. We have electric concrete vibrators and gas-powered vibrators for versatile jobsites. High-cycle concrete vibrators are designed for low slump, stiff concrete mixes where you need the extra help to get the material around corners or rebar. Get the job done right the first time by ensuring a clean finish and maximum stability.
FAQs About Concrete Vibrators
Why do you vibrate concrete?
- Wet concrete contains around 20% air in the mix. When the concrete dries, that air can create multiple defects such as honeycomb and cold shuts. Concrete vibrators move the concrete solution into any cracks and force all of the bubbles up to the surface, leaving a consolidated and compacted mixture where you need it. This ensures smooth and strong concrete fill before you take away supports.
How long should I vibrate concrete?
- Typically, the process of vibrating concrete takes somewhere between 5 and 15 seconds. If there are still bubbles in the concrete when the concrete vibrator is removed, repeat this procedure until all bubbles are gone.
How do I vibrate concrete in columns?
- Concrete vibrators should always be used vertically whether it is in a column, wall or slab. As long as you can use the internal vibrator in proper form, it should work the same as in a slab. Depending on the stiffness of the mix, you may need to use a vibrator with a medium or large diameter. Not sure what you need? Call United Rentals today at 844-368-6303.
How do I vibrate concrete properly?
- Lower the vibrator into the concrete vertically, letting it smoothly descend all the way to the bottom of the slab or the previous lift laid by around 6 inches. Allow between 5 and 15 seconds of vibration then pull it up slowly. As it reaches the top of the concrete, you will see air bubbles escape from the surface. This is a good sign that the lower layers of concrete are settling with no bubbles. Then reinsert it nearby, so that the vibration radius (included in the specs of the machine) overlaps the radius of the previous spot. Continue using the vibrator until you no longer see air bubbles when removing it. When you don't see any more bubbles, the concrete has been properly vibrated. Low slump or stiff concrete mixes will need a concrete vibrator with higher amplitude than higher slump mixes. Do not rush this task. If it isn't done properly, the structure may be unstable when it cures.
Should all concrete be vibrated?
- In general, vibration is a good practice in order to stabilize concrete. However, there are specific concrete mixes called self-consolidating concrete that do not need vibration. Verify what kind of concrete mix you will be using for the job.