A bit of fun maths for you in the morning!

[MK-2]

I know there will be someone here who works this out.

We are ripping up our current patio to lay a new one. We need to order a skip to get rid of the slabs, but obviously don't want to overfill the skip in terms of weight so want to work out how much the slabs weigh.

they are 600mx600m slabs (approx 2" thick) and we have about 40 to get rid of.

Is there a sort of general weight of concrete that can be applied to this?

 

I think the 8yard skip can take up to 8 tonnes but obviously if i could get away with a smaller skip and smaller weight limit it would lower the cost

[MK-2]

Not sure if I found an answer just after posting. Just wanted to see if this makes sense to anyone?

 

Paving Expert - AJ McCormack and Son - Pre Cast Concrete BS Flags <-- that site at the bottom says that a 600mx600m (2" thick) slab will weigh approx 41kg each.

So 41kg * 40 = 1640kg which equates to 1.64tonnes? Does that sound about right, 40 patio slabs weighing just over a tonne and a half?

[Steve21]

they are 600mx600m slabs (approx 2" thick) and we have about 40 to get rid of.

 

Well under the assumption that's 600mm, not meters? Unless I worked something out wrong, 0.6*0.6*0.05*40 is 0.72~ barely 1m3

 

Norm concrete 2.5~ tonnes per m3, so say 2 tonnes. (Assuming slabs not normal though) Unless i did somethign wrong, nowhere near 8tonnes. (Might want to double check the maths but hey )

 

Steve

[MK-2]

yeah sorry 600mm, thats me typing in haste!

 

these are the sort of slabs, 600mm by 600mm and 2 inch thick. they weigh a fair bit each, but once you are loading stuff into a skip its hard to just say "yep thats about 2 tonne in there" so wanted to check first

 

so you're saying 40 slabs would work out approx 2 tonne?

[TechMonkey]

Concrete has a density of around 150lbs per cubic foot (so I've heard I don't have that off the top of my head!!), 600mm is about 2ft so 2*2*(1/6)*150 = 100lbs. 2000 pounds in a ton so you should be able to 160 in that skip ((2000*8)/100).

 

Hope my workings out are correct now!

[Steve21]

yeah sorry 600mm, thats me typing in haste!

 

these are the sort of slabs, 600mm by 600mm and 2 inch thick. they weigh a fair bit each, but once you are loading stuff into a skip its hard to just say "yep thats about 2 tonne in there" so wanted to check first

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so you're saying 40 slabs would work out approx 2 tonne?

 

Well it's less I'd say nearer what you said, 0.72 x 2.4k is roughly 1.728~ but just rounding it a bit That's basing it on "standard concrete" weight anyway. Unless we both worked something out majorly wrong that is

 

Steve

[Hightower]

[ATTACH=CONFIG]10996[/ATTACH]

 

Oh, those are nasty. My brother has some of those in his garden from when he bought the house. He keeps saying he's dying to get rid of them, but it's been 8 months now and they are still there - I think he secretly likes them!

[MK-2]

just so we're all clear, if the skip buckles under these slabs im holding you all personally responsible

[MK-2]

Oh, those are nasty. My brother has some of those in his garden from when he bought the house. He keeps saying he's dying to get rid of them, but it's been 8 months now and they are still there - I think he secretly likes them!

 

thats just a pic off that site, but ours are a bit similar. just uploading a pic from my phone as ive been taking in progress pics all the way, so you can see the state of ours.

 

we've been in the place about 10 months and decided its time ours went too!! definitely dont like them. plus they aren't laid properly, the hardcore under isn't compacted well enough.

 

these are ours:

Edited August 12, 2011 by MK-2

[Hightower]

Don't forget to include the cat when calculating weight for the skip. I think it'll take about 0.004 tonnes per cat. Wouldn't want you going over the limit, that's all

[MK-2]

thats not even our cat, its next doors. she sat and watched us moving loads of stuff last night.

 

anyway why am i even listening to you, you're working out the weight of a lion, not a house cat

[Hightower]

thats not even our cat, its next doors. she sat and watched us moving loads of stuff last night.

 

anyway why am i even listening to you, you're working out the weight of a lion, not a house cat

 

Let me google that for you

 

And I only said 4 kilos because a) to take into account really big cats b) because I look at cats like those naughty rioters and each cat is sure to have a few electrical goods in their coats and c) because I'm not a cat person in the slightest and don't know what they weight and d) because it's really hard to judge a cats weight just by kicking them

[mac_shinobi]

or you could just pull one slab up, get all the mud and stuff off and weigh one and * by 40 ?

[SYNACK]

just so we're all clear, if the skip buckles under these slabs im holding you all personally responsible

 

Not to spoil this beautiful thought exercise but if you want assurance what is stopping you from simply ripping one up, weighing it and multiplying that weight by 41. I know its rather dull but would get you a reasonably accurate figure without involving a bunch of (reasonably accurate) assumptions.

[MK-2]

Not to spoil this beautiful thought exercise but if you want assurance what is stopping you from simply ripping one up, weighing it and multiplying that weight by 41. I know its rather dull but would get you a reasonably accurate figure without involving a bunch of (reasonably accurate) assumptions.

 

i don't think our kitchen weighing scales go up that far (and we don't have bathroom scales)

[mac_shinobi]

Not to spoil this beautiful thought exercise but if you want assurance what is stopping you from simply ripping one up, weighing it and multiplying that weight by 41. I know its rather dull but would get you a reasonably accurate figure without involving a bunch of (reasonably accurate) assumptions.

 

Sure I said that above as well - not fussed that you said the same thing as OP paid attention to your comment lol.

 

Only asking to weigh one not all 40 at the same time lol

 

Borrow a neighbours scales or buy one ??

Edited August 12, 2011 by mac_shinobi

[MK-2]

Sure I said that above as well - not fussed that you said the same thing as OP paid attention to your comment lol.

 

Only asking to weigh one not all 40 at the same time lol

 

i saw both comments, just clicked reply with quote to one but my point still stands. if these weigh anywhere near 40kg roughly, our kitchen weighing scales are meant for weighing food. so unless i was planning on cooking three quarters of a cow i don't think i'd have need to weigh 40 kilos on kitchen scales:p

[tumbleweed]

With a Relative density of around 2.4, these will wight around 40 KG - and I've shifted enough to confirm that's about right -- get onto the larger 900*600 ones at around 60KG and you know you're lifting something.

 

Can we have a 'how many sweets in the jar ?' type contest - my guess is 1750 KG.

 

Or, have you thought of freegle (was freecycle) - you may get rid of them for free ??

[MK-2]

With a Relative density of around 2.4, these will wight around 40 KG - and I've shifted enough to confirm that's about right -- get onto the larger 900*600 ones at around 60KG and you know you're lifting something.

 

Can we have a 'how many sweets in the jar ?' type contest - my guess is 1750 KG.

 

Or, have you thought of freegle (was freecycle) - you may get rid of them for free ??

 

i had considered freecycle (got rid of some canoes that way) but we need a skip for other rubbish so it will just be easier

i've already smashed up part of a concrete path that was about 5 inches thick, plus removed 4 stumps from conifers, i'm not looking forward to having to then crack on with all the slabs.

[mac_shinobi]

i saw both comments, just clicked reply with quote to one but my point still stands. if these weigh anywhere near 40kg roughly, our kitchen weighing scales are meant for weighing food. so unless i was planning on cooking three quarters of a cow i don't think i'd have need to weigh 40 kilos on kitchen scales:p

 

I never meant kitchen weighing scales I meant normal ones - you know the bathroom kind that you normally stand on to see how much you weigh ie 10 stone or whatever ?

 

Would that classify as half a cow ? lol

 

edit - shame you are in Notts assuming your profile info is correct as I'm after some slabs - will post back later

[MK-2]

I never meant kitchen weighing scales I meant normal ones - you know the bathroom kind that you normally stand on to see how much you weigh ie 10 stone or whatever ?

 

i don't think our kitchen weighing scales go up that far (and we don't have bathroom scales)

 

from my earlier post - we dont have any

[Hightower]

I never meant kitchen weighing scales I meant normal ones - you know the bathroom kind that you normally stand on to see how much you weigh ie 10 stone or whatever ?

 

Would that classify as half a cow ? lol

 

edit - shame you are in Notts assuming your profile info is correct as I'm after some slabs - will post back later

 

Where are you based? Might have some you can have but based in NE

[Achandler]

A local scrap merchant will probably take them off you, and maybe even collect.

[mac_shinobi]

Where are you based? Might have some you can have but based in NE

 

Will inbox you