A concrete vibrator is used when newly poured concrete is settling, when concrete is poured into a foundation or mold it creates air bubbles within the mixture. If these air bubbles are not removed it will weaken the structure and not allow it to bond to the rebar inside the slab. These machines are inserted into the settling concrete and will shake or vibrate out the the tiny air bubbles to create a stronger, long lasting pour. These machines have 3 parts to them: a motor, shaft and head. These three components come in various sizes, lengths and horsepower dependent on the size of the pour.
-Improve surface appearance and minimize patch work
-Slow down rust causing elements by creating a dense compaction
-Allow the cement to bond to rebar to create maximum strength
-Eliminate rock pockets and lift lines
For Best Results:
-Allow the head to sink under its own weight vertically when inserting, forcing it may get it stuck in rebar
-Hold the unit in place for 5 – 15 seconds then pull it up slowly, if it’s a large or deep pour the head should be held in place every 2 ft for about 15 seconds to avoid trapping any air
-When pulling up from the concrete a slight up and down movement will close the hole formed by the head
-When reaching the top of the pour remove head and shaft quickly to prevent air getting trapped in top layer
-When removing head from concrete let it pass 3-6 inches from the previous layer to ensure a tight bond and preventing lift lines
-Pours should not be more then 2 – 3 feet high so the air has a chance to escape
By using the methods above the aggregate will consolidate and bond together to create a long-lasting slab. In the end a vibrator will remove trapped air bubbles, create a strong bond and create less shrinkage cracks, less bleeding and segregation of the pour.