Any structual Engineers/Underpining know-hows? {pics}

[Andehh]

Property renovation in the peak district, on a hillside.

Driveway needs to be extended for a Double garage, but due to the hillside requires some form of underpinning/support. Structural engineer & builder originally suggested a line of a dozen gabions would be sufficient, but several weeks later structural engineer is now saying he wont sign off on anything short of a FEW dozen.

The site has very limited access, so nothing bigger then a dustbin lorry can get near it, and due to a short driveway & very old stone walls nothing bigger then a small couple tonne dump truck can actually get on site.

Now, my parents nigh on broke themselves hand filling these dozen gabions over a period of a few week so are obviously devastated at the thought of needing to move them & then re-fill 2-3 times as many...by hand. So I am hoping to step in and try and find alternative solutions.

Below images show the issue, and half of the problem with such a ''small'' site to be handling the movement of 20-30 gabions!

My current ideas are:

1) 30 Pre-filled gabions, delivered on 3-4 3 axle truck and HIAB'D over wall, 8 tonne Excavtor with fork attachment to move them into position. Excavator used to dig out slope to underpin.

2) Friendly farmer allows (not asked yet...) us to dump 30 tonnes of rock on his land, to then use a small dump trucker & digger to move onto site and ''pour'' into positioned gabions to fill on site

3) Bagged crushed rock delivered to site via HIAB over wall, excavator used to lift them & cut the bottom to fill gabions at base of slope.

4)....Any suggestions?

The bank in question, showing gradient & height change.




Looking up at top of ridge, showing house opposite, there is a single lane & single width driveway (tbc) above ridge



Looking at the top of the ridge, where the driveway will be. Approx 10m x 10m for turning circle/parking. The piling shown is to underpin the garage.

Edited by Andehh on Wednesday 28th September 08:56

Edited by Andehh on Wednesday 28th September 09:06

[Lesgrandepotato]

Why do the original ones need moving? are you not 33% there? Just crack on with it!

[Andehh]

They need to dig back the land behind them. An excavator with a fork attachment should hopefully be able to move then to save dismantling.

Just seeing if anyone has any other ideas or options before you return we start trying to make it work.

[Lesgrandepotato]

Makes sense - I'd get the digger man down for a squiz, he might be able to do from the top or side with a larger machine?

[Andehh]

Work has to be done from the top of the slope due to a buried calor gas tank (I'm virtually standing on it in second pic), and garage obviously being built.

Would an 8 tonne digger reach from top of slope to this lower gabions? Maybe a grab bucket to remove spoil behind those gabions to install a second row?

[Tom_C76]

If you can get the soil out you could shoot mass concrete behind the gabions you've already got in place. Just place a sheet of correx or similar against the gabion so you don't fill it with the concrete. Wouldn't need to be as wide as the gabion design either as the concrete is more dense than stone fill.

[Tom_C76]

Or build a Timbercrib wall instead.