COBBLES & BOULDERS = AN ARCHILLES HEAL OF SCREW PILES?

Whenever I see boulders and cobbles it makes me very nervous. There is absolutely no doubt in my mind that any deep foundation system will have it's challenges getting into and through this material.

Normally, in the past, if my esteemed colleagues and I saw cobbles and boulders - we would suggest that screw piles will struggle. This is because the nose of the pile may spin on the top of a boulder.... or a boulder may get jammed in the helix flight.... and we would stick to what geotechnical materials screw piles are good for.

HOWEVER

The best thing about a screw pile is that it can hit a cobble/boulder and if it can't pass through - then it can be easily "unscrewed" - just as easily as it was screwed in to that point.

However when a client comes to you and says they are already having challenges using other methods - I just struggle to say "NO" to a challenge!

See the later blog post for more information…

Cobbles and boulders whilst screw piling.

Suitable for screw piles?