Heavy statue - ground floor

PlacidCasual · 14 Jun 2019 at 10:02

That's 4 tonnes per square meter. If you have a suspended floor that will only span two joists on either 400mm or 600mm centres. No way in hell that any joist is going to accept that load. A quick google and found some joist charts and they go up to 1.5 tonnes per square meter. But even then that probably assume a distributed load.

If you have a suspended floors you're boned. If you have concrete you'll probably want a structural engineer to calculate the load based on the known screed thickness. It's entirely feasible it can be put down it may be you need a spreader plinth to reduce the point loading.

spluff · 14 Jun 2019 at 10:13

PlacidCasual said:
That's 4 tonnes per square meter. If you have a suspended floor that will only span two joists on either 400mm or 600mm centres. No way in hell that any joist is going to accept that load. A quick google and found some joist charts and they go up to 1.5 tonnes per square meter. But even then that probably assume a distributed load.

If you have a suspended floors you're boned. If you have concrete you'll probably want a structural engineer to calculate the load based on the known screed thickness. It's entirely feasible it can be put down it may be you need a spreader plinth to reduce the point loading.

I have no idea whats underneath - I would have to take up the new carpet and the boards. Even then I wouldn't know how thick the screed is if its concrete...…

vanpeebles · 14 Jun 2019 at 10:14

You had best go look

cheesyboy · 14 Jun 2019 at 10:17

Impulse purchasing a half-tonne statue. Sometimes you just gotta have it tho'

Mark A · 14 Jun 2019 at 10:17

Please update the thread on how this goes!

I think you will need to call in a builder to reinforce the resting place for this beast. You don't want that thing falling over! Then maybe lay down some sheets of thick plywood over the floor that leads up to the spot it's going in.

sovietspybob · 14 Jun 2019 at 10:18

If there's chipboard under the carpet it'd probably be a suspended floor, i no way that'd support that weight.

I'd get a structural engineer round to advise, as even on a concrete floor it'd need to be fairly beefy to take that much weight on a small area.

As said you'll also really want it secured to the new floor in some meaningful way i'd have thought.

thezappa · 14 Jun 2019 at 11:50

Really intrigued how this is going to pan out. Also was there any thought about any of this prior to hitting the button…

Akagi · 14 Jun 2019 at 11:59

Amazing thread in the making. Following

spluff · 14 Jun 2019 at 12:01

OK I have called an engineer and he has given me some advice but without looking at substructure of floor...… (obviously its an opinion over phone and he said would need to come out and lift flooring for a better idea but feels like it should be okay)

He said the statue is approximately 5800 newtons for 600kg / The base of statue is 500mm x 300mm

The load is in the corner so will be more stable than in centre of room

If concrete he estimates:-

statue will be loaded over 2 blocks / 150mm deep / 100mm wide

sheer stress = 5800 / 2 / 150 / 100 = 0.19

If wooden he estimates

statue would be loaded over 3 timbers / centres 450 / 225mm deep / 50mm wide

sheer stress = 5800 / 3 / 225 / 50 = 0.17

He said concrete has tensile strength of 3newtons

He said any stress under 2 is fine for both materials

How does this sound

thezappa · 14 Jun 2019 at 12:09

It sounds like you need to get the engineer out to give you an informed decision.
Giving estimates over the phone is one thing but looking at it and calculating it properly is another.
Personally I’d belt and braces and strengthen the floor up to the eyeballs but then I’m not putting a half tonne statue in my hallway

vanpeebles · 14 Jun 2019 at 12:17

I'd do it a bit like a washing machine floor, but dig it out more, with fill with concrete.

robfosters · 14 Jun 2019 at 12:26

I think your best plan is to sell your house, buy a plot of land, place statue in position and then build new house around it.

PlacidCasual · 14 Jun 2019 at 12:32

At first glance his rationale for shear stress if the statue is placed in the corner seems ok. (Assuming the beams are supported in the corner and it's not a false stud wall.) The tables I looked up would have been predicated on bending moment at the centre of the span not shear stress.

spluff · 14 Jun 2019 at 12:34

PlacidCasual said:
The tables I looked up would have been predicated on bending moment at the centre of the span not shear stress.

What does that mean Placid? It will bend in the centre of the statue area?

cheesyboy · 14 Jun 2019 at 12:42

spluff said:
If wooden he estimates

statue would be loaded over 3 timbers / centres 450 / 225mm deep / 50mm wide

sheer stress = 5800 / 3 / 225 / 50 = 0.17

He said concrete has tensile strength of 3newtons

He said any stress under 2 is fine for both materials

How does this sound

Sounds like his calculations are saying you could mount a fire engine on top of a dustbin on your wooden floor, and it could take it as static weight.

And I'm not sure it could

PlacidCasual · 14 Jun 2019 at 12:45

The shear stress is strength of the beam to breaking clean off from the wall, at it's root for instance. It's generally the strongest case.

On a long beam, say 4 metres. If you put the load in the middle the bending moment is increased because of the length. So it's not the shear stress that causes it to fail but the bending moment. This will be related to the point load, the length and beam shape. The load that can be sustained in the middle of the beam is significantly less than can be sustained at it's edge.

The structural engineer seems to have ignored the bending strength and just worked out the strength at the edge. If the beams are supported at the corner which is a reasonable assumption unless it's a decorative stud wall then you can ignore the bending strength.

edit: OK re did the calcs. I work the stress out at 13N/mm2 at the centre of a 4m beam. Which is 6 times your engineers 2N/mm2 limit. Assuming I'm comparing apples and apples. (It's been a while). Which is why it's ok at edge but not in centre.

spluff · 14 Jun 2019 at 12:49

Its an internal wall but banging on it it feels solid and not hollow like stud wall... so does that mean the bending strength is ignored because its in corner....

Mark M · 14 Jun 2019 at 12:52

Best thread in a long time, I look forward to seeing how it pans out. Are your doors wide enough to get a forklift through?

thenewoc · 14 Jun 2019 at 12:55

This is impulse buying at it's best. This could be a sketch from Only Fools and Horses as a follow up to the chandelier episode.

You should live stream the delivery to youtube the ad revenue could be a nice little earner.

thenewoc · 14 Jun 2019 at 13:01

Trotter's Objet D'art Installations - Mange Tout Rodney, Mange Tout