Pile Under Reamer/Bell Mouth Tool

[Me2]

This is a tool I made a couple of years ago for Bell Mouthing the base of piles I sunk through my workshop floor (29 in total). The back of the workshop slab had sunk over 80mm and was continuing to sink at a rate of 1mm per month. I had sort the advice of professionals experienced in slab lifting and clay stabilization but at a cost of $22,000 AU this was out of the question. The guarantee for this work was like a colander, full of outs for the contractor with all the onus for any issues back on me. I organized for a Geo-Tech sample and report to be undertaken with the results (as I had assumed) coming back as unstable clay down to 1.5 Meters. I needed to increase the bearing area of any piles I sunk to ensure no movement of the slab once re-leveled and under load. As a result I designed and made a hand operated Under Reamer/Bell Mouth Tool to open out the base of the piles to 500mm from a pile diameter of 170mm to achieve this higher rated bearing load for each pile. It has now been 18 months since I completed this work and I can say that the slab is now rock solid with no movement other than some initial re-settling.

Part 1 of the Bell Mouth Tool build

Part 2 of the Bell Mouth Tool build

Showing the Bell Mouth Tool in action

The initial kick off video to the Slab Lift Series.

[peter_351]

Hi Me2 , love your Utube channel , what suburb/state are you in Australia ? you certainly took on a big undertakings of works to rectify the concrete slab sink. Keep up the good work

Cheers from Melbourne Australia

[Me2]

G'Day Peter, just down the road in Geelong.
Cam

[Nitrous]

how are you going to actually lift the slab, or is this simply an effort at stabilization?
Great video!
Thanks
Doug

[Nitrous]

did you do a video on how you leveled the slab?

[Me2]

G'Day Nitrous, yep if you have a look at the video's you will see how I lifted the slab and re-leveled it using the home made strong backs. It is now within +-6mm all over using the water level. I did a similar thing to my house when the slab broke its back and put a huge gap in the brickwork 12 years ago. Even today you cannot pick where it was, the perfect repair.
Cam