How much does it cost to dig a really big hole?
Discussion
Deep hole will need health and safety risk assessment, possible shoring up. How deep is the soil before rock? What is the water table level? How stable is the soil? Has a ground investigation been done? What about legal rights of support? What about mines and minerals rights? Spoilt has to be disposed of legally, loads of factors that a man with a digger will ignore and possibly leave the op open to prosecution.
Basically, you cant just dig a massive hole and expect it all to be alright.
In development, a large portion of the cost is in the ground works
Basically, you cant just dig a massive hole and expect it all to be alright.
In development, a large portion of the cost is in the ground works
Of course this hole digging is ignoring that it's going to be used as an access route into a basement for a big bit of equipment so there will be work inside the hole to create a substantial access portal in the basement wall (& make the portal good again afterwards) as well as getting the tank into the hole & shifted through the access into the basement - non-trivial as I expect it weighs a bit so would probably need a surface to work on?
Also no real mention of ground conditions, water levels or restrictions on the location & access to it.
I'd almost wonder if it might be simpler to make the access semi-permanent rather than just digging a hole in the mud and trying to backfill it.
Has anyone considered making the hole into the building at ground level then dropping through the floor instead?
Also no real mention of ground conditions, water levels or restrictions on the location & access to it.
I'd almost wonder if it might be simpler to make the access semi-permanent rather than just digging a hole in the mud and trying to backfill it.
Has anyone considered making the hole into the building at ground level then dropping through the floor instead?
Jonesy23 said:
Has anyone considered making the hole into the building at ground level then dropping through the floor instead?
It's an option. Unfortunately most of the floor is radiation shielding, so 5ft thick concrete, and not trivial to cut through.Thanks for the input everyone. I realise it was a vague question so expected a range of answers! Hopefully I will update the thread when I get some more information. A different, very heavy, piece of equipment was moved into the building about a decade ago so there are detailed ground surveys. It's just working out who still has the info that's a problem at the minute!
Muncher said:
If it is just a case of digging a hole and nothing more then a 13 tonne digger can dig to a depth of 5.5m
You have 160 cubic meters of soil to dig, say a volume of 200m3 loose, not having to move it far.
Maximum capacity on the biggest 1200mm bucket is 0.8 cubic meters. That's "only" about 260 buckets full, which for one man in a digger plus another in a dumper looks easily doable in a day, so less than £500. I suspect there is rather more to it than that, not least making sure the basement doesn't cave in when back filling but that's another story.
Are you real? It's 200m3 of non-loose soil moved and then 200m3 of loose soil moved again, that could mean potentially moving 650+t of soil, in a day, with a 13t machine and say a 9t dumper? You have 160 cubic meters of soil to dig, say a volume of 200m3 loose, not having to move it far.
Maximum capacity on the biggest 1200mm bucket is 0.8 cubic meters. That's "only" about 260 buckets full, which for one man in a digger plus another in a dumper looks easily doable in a day, so less than £500. I suspect there is rather more to it than that, not least making sure the basement doesn't cave in when back filling but that's another story.
Even though its ridiculously unrealistic to achieve the above, it still wouldn't be £500, 13t excavator, that's £100 each way, probably get the dumper on free. 13t Fuel £70? Dumper Fuel £40? Hire Rates minimum £224 & £176. That's £710 basic, to be honest I wouldn't even mobilise my kit for that even if the objective was achievable. To get a 13t & 9t dumper on site for one day only, your looking at a grand minimum IMO.
Realistically, to answer your question i.e. moving 200m3 of soil and then back filling same, I'd ballpark it at about £2k.
hairykrishna said:
Unfortunately most of the floor is radiation shielding, so 5ft thick concrete, and not trivial to cut through.
That suggests the walls holding that floor up will also be non-trivial to get through to get the vessel in.What about getting the vessel supplier to come over with some bent metal and weld the vessel in situ? You'd think that would be cheaper if it's at all feasible.
Or put the vessel outside and pipe the contents in and out of the building?
To get it in via a hole you want to dig as small a hole as possible, so the vessel goes in at ceiling level and is craned into the hole on a platform and transferred through the hole onto a scaffold platform to then be lowered to the floor. Where would that approach leave you in terms of the hole size?
Edwin Strohacker said:
Im still filling one of those b
ds in because the last bloke to live here couldn't just buy an ordinary trampoline like anyone normal. 
Undoubtedly a massive hole in the garden is annoying, but is that a reason to start burning plastic in your garden and filling your neighbour's houses with toxic, stinking smoke?ds in because the last bloke to live here couldn't just buy an ordinary trampoline like anyone normal. hairykrishna said:
Jonesy23 said:
Has anyone considered making the hole into the building at ground level then dropping through the floor instead?
It's an option. Unfortunately most of the floor is radiation shielding, so 5ft thick concrete, and not trivial to cut through.Thanks for the input everyone. I realise it was a vague question so expected a range of answers! Hopefully I will update the thread when I get some more information. A different, very heavy, piece of equipment was moved into the building about a decade ago so there are detailed ground surveys. It's just working out who still has the info that's a problem at the minute!
ds, even if they act like it.Evoquative said:
Edwin Strohacker said:
Im still filling one of those bds in because the last bloke to live here couldn't just buy an ordinary trampoline like anyone normal.
Undoubtedly a massive hole in the garden is annoying, but is that a reason to start burning plastic in your garden and filling your neighbour's houses with toxic, stinking smoke?ds in because the last bloke to live here couldn't just buy an ordinary trampoline like anyone normal. Thought I'd post a quick update. After looking at various options for how we're going to fit the new machine into the building we've decided that we need more space to do what we want to do well. Given that, it makes much more sense to construct a room in our proposed 'big hole' to house the accelerator pressure vessel permanently and use the existing structure for beam rooms. First steps are a detailed ground survey to check feasibility so that's being arranged at the moment.
hairykrishna said:
Thought I'd post a quick update. After looking at various options for how we're going to fit the new machine into the building we've decided that we need more space to do what we want to do well. Given that, it makes much more sense to construct a room in our proposed 'big hole' to house the accelerator pressure vessel permanently and use the existing structure for beam rooms. First steps are a detailed ground survey to check feasibility so that's being arranged at the moment.
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