On Wed, 12 Oct 2016 21:36:06 +0100, The Natural Philosopher
wrote:


And then those with even half a clue realised that polystyrene is much
cheaper.
What is the "foamed concrete" which get mentioned when sinkholes get
filled ?

If its what I think it is, its what it says. Concrete with air or other
gas bubbles in it. Maybe they use baking powder as well as cement ;-)

I found a cafe using that recipe for its cakes the other day, at least
they seemed that way.

G.Harman

On 11/10/2016 14:49, Dave Plowman (News) wrote:
In article ,
T i m wrote:
Yes I know EPS floats but I didn;t know carparks used it for hardcore.

No, nor did specifically I but I knew it was used for underfloor
insulation so also knew it was capable of supporting some fairly heavy
loads (like under kitchens etc). ;-)

Mate's 80s house is built on a concrete slab. With 4" poly on top, and
chipboard on that for the floor.

Standard construction method back then.

Unfortunately the cheepo 'expanded' polystyrene (unlike the better
quality extruded variety) is open cell so water can seep into it,
and in places like the foot wide strip in front of kitchen units,
or well used doorways, it can start to compress with age and
give you a bouncy floor.

This happened to my cousin who bought a new-build house in the 80's
which was timber framed as well, sitting on a beam and block ground
floor itself overlaid with EPS and chipboard.

On 11/10/2016 15:41, Chris J Dixon wrote:
T i m wrote:

I wonder if the same people watched that Grand Designs recently where
they built a *house* beside a river but built it on a large 'float'
so it would rise up if there was any flooding?

I did hear somewhere that large swimming pools sometimes have a
special valve fitted so that if the water table rises whilst it
is empty it doesn't just pop out of the ground.

Chris

I wonder if TML incorporated something like that at the very big
underground chunnnel interchange at Sangatte ?.

On 12/10/2016 11:49, T i m wrote:
On Tue, 11 Oct 2016 15:41:50 +0100, Chris J Dixon
wrote:

T i m wrote:

I wonder if the same people watched that Grand Designs recently where
they built a *house* beside a river but built it on a large 'float'
so it would rise up if there was any flooding?

I did hear somewhere that large swimming pools sometimes have a
special valve fitted so that if the water table rises whilst it
is empty it doesn't just pop out of the ground.

Fascinating ... showing there is little difference between an empty
swimming pool and a concrete barge ... or a multi-story car park floor
and a pontoon or crude car ferry. ;-)

Cheers, T i m

Or the Mulberry pontoons, built in 1941 and 1942, then sunk to hide
them, then pumped out, and floated across the Channel and sunk again.

If you head to Lepe country park near Fawley (Southampton) you will
find the remains of the onshore contruction and ramps used to build
the things prior to 'launching'.

On 11/10/2016 12:00, Malcolm Race wrote:
On 11/10/2016 11:20, Huge wrote:
On 2016-10-11, Tim Lamb wrote:
In message , Andy Burns
writes
Brian Gaff wrote:

I did wonder why it was there

Big hole to fill? Concrete £100/cubic metre, EPS £15/cubic metre ...

Trenches in clay would be sided with foam to allow for movement.

If you've ever driven up the A1(M) through Hatfield, the walls of the
tunnel
under the shopping centre are full of expanded polystyrene. I watched
it being built.

Pilars for concrete bridges are often built with concrete poured around
an EP core

Malcolm
That's because a hollow concrete structure is as strong as a solid
version and is cheaper to build. The EPS is just being used a
non-removable former, while the outside formers will have been
made on site with 18 mm ply, plus ready made shuttering.

Concrete takes ages to cool down. When the Hoover dam was built
they poured the concrete in cubes in a specific pattern to allow
each cube to cool sufficiently to allow the ajoining cube to be
poured.

On 12/10/2016 16:13, jim wrote:
harry Wrote in message:

Obviously they never put a drain under it.


Or the flood water came up through the drain under it...

Utterly irrelevent since the water came up under the soil and lifted
the insulation up. Anyone who thinks that the laws of physics can
be negated with a drain needs a better education (or brain).

A drain *through* it might have been better, just flooded cars in
a car park

Expanded polystyrene was being phased out when I was involved in favour of expanded polypropelene.

Wouldn't have made any difference.

On 13/10/2016 07:08, harry wrote:

I've seen concrete made with blast furnace slag as aggregate.
The slag is full of gas bubbles and is a waste product hence very cheap.


The nearest blast furnace to LOndon is about 200 miles. Transport
costs would be astronomic. Put your 'brain' in gear.

In article ,
Andrew wrote:
Mate's 80s house is built on a concrete slab. With 4" poly on top, and
chipboard on that for the floor.

Standard construction method back then.

Unfortunately the cheepo 'expanded' polystyrene (unlike the better
quality extruded variety) is open cell so water can seep into it,
and in places like the foot wide strip in front of kitchen units,
or well used doorways, it can start to compress with age and
give you a bouncy floor.

This happened to my cousin who bought a new-build house in the 80's
which was timber framed as well, sitting on a beam and block ground
floor itself overlaid with EPS and chipboard.

The poly has survived OK. More than can be said for the chipboard floor in
the kitchen.

--
*If one synchronized swimmer drowns, do the rest have to drown too?

Dave Plowman London SW
To e-mail, change noise into sound.

On Fri, 14 Oct 2016 13:26:32 +0100, Andrew
wrote:


Fascinating ... showing there is little difference between an empty
swimming pool and a concrete barge ... or a multi-story car park floor
and a pontoon or crude car ferry. ;-)

Cheers, T i m

Or the Mulberry pontoons, built in 1941 and 1942, then sunk to hide
them, then pumped out, and floated across the Channel and sunk again.

If you head to Lepe country park near Fawley (Southampton) you will
find the remains of the onshore contruction and ramps used to build
the things prior to 'launching'.

Some bits never made it ,
http://www.geograph.org.uk/photo/1323168 off Kent.
http://www.geograph.org.uk/photo/2873462 near Portsmouth

And some bits came back to be reused.
Many a happy holidaymaker once drove across this section of roadlink
on their way to the Isle of Wight until about 45 years ago when the
vessels got bigger,
http://ship-tracking.co.uk/Shipchat/...e/80196-tn.jpg

it now rests rusting unnoticed at the Southampton terminal.
http://www.geograph.org.uk/photo/2873462


G.Harman

On 10/14/2016 1:39 PM, Andrew wrote:
On 12/10/2016 16:13, jim wrote:
harry Wrote in message:

Obviously they never put a drain under it.


Or the flood water came up through the drain under it...

Utterly irrelevent since the water came up under the soil and lifted
the insulation up. Anyone who thinks that the laws of physics can
be negated with a drain needs a better education (or brain).

A drain *through* it might have been better, just flooded cars in
a car park

Expanded polystyrene was being phased out when I was involved in
favour of expanded polypropelene.

Wouldn't have made any difference.



Actually it's not quite as simple as that, it all depends on the source
and distribution of the water, compared to the location of the drain.

If the water table all around the car park can get all the way up to the
deck level, then I agree, the drain does nothing.

But say the leak was in the middle, right under the "drain". Then, there
is not much pressure left at the leak site, just the head associated
with its depth. So it might take some time to saturate all the ground
under the deck, all the way to the edges. One reason the water table
rose so quickly and effectively might be that it was driven by 3 bar or
more pressure from the main.

On Friday, 14 October 2016 16:23:58 UTC+1, jim wrote:
Andrew Wrote in message:
On 12/10/2016 16:13, jim wrote:
harry Wrote in message:

Obviously they never put a drain under it.


Or the flood water came up through the drain under it...

Utterly irrelevent since the water came up under the soil and lifted
the insulation up. Anyone who thinks that the laws of physics can
be negated with a drain needs a better education (or brain).


Irrelevant has an a, but that is irrelevant.

Reading the thread readers would note I was responding to harry's
dribble about it obviously not having a drain under it. My point
was that if the surrounding area is flooded (which it was) any
drain under that foam etc would more than likely have helped
direct floodwaters exactly under it and help make if float rather
than help it not float...

A drain *through* that construction would likely have resulted in
a flooded car park and not a floating floor slab...

Well the water has to be got rid of somehow.
There can't have been any water under it come to think.
How could they dig the hole? It would just fill up.
So a drain would have to be put in at the time of construction.

Andrew Wrote in message:
On 12/10/2016 16:13, jim wrote:
harry Wrote in message:

Obviously they never put a drain under it.


Or the flood water came up through the drain under it...

Utterly irrelevent since the water came up under the soil and lifted
the insulation up. Anyone who thinks that the laws of physics can
be negated with a drain needs a better education (or brain).


Irrelevant has an a, but that is irrelevant.

Reading the thread readers would note I was responding to harry's
dribble about it obviously not having a drain under it. My point
was that if the surrounding area is flooded (which it was) any
drain under that foam etc would more than likely have helped
direct floodwaters exactly under it and help make if float rather
than help it not float...

A drain *through* that construction would likely have resulted in
a flooded car park and not a floating floor slab...

--
Jim K


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

harry Wrote in message:
On Friday, 14 October 2016 16:23:58 UTC+1, jim wrote:
Andrew Wrote in message:
On 12/10/2016 16:13, jim wrote:
harry Wrote in message:

Obviously they never put a drain under it.


Or the flood water came up through the drain under it...

Utterly irrelevent since the water came up under the soil and lifted
the insulation up. Anyone who thinks that the laws of physics can
be negated with a drain needs a better education (or brain).


Irrelevant has an a, but that is irrelevant.

Reading the thread readers would note I was responding to harry's
dribble about it obviously not having a drain under it. My point
was that if the surrounding area is flooded (which it was) any
drain under that foam etc would more than likely have helped
direct floodwaters exactly under it and help make if float rather
than help it not float...

A drain *through* that construction would likely have resulted in
a flooded car park and not a floating floor slab...

Well the water has to be got rid of somehow.
There can't have been any water under it come to think.
How could they dig the hole? It would just fill up.
So a drain would have to be put in at the time of construction.


Er Yerss.....
--
Jim K


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

Andrew wrote:

Concrete takes ages to cool down. When the Hoover dam was built
they poured the concrete in cubes in a specific pattern to allow
each cube to cool sufficiently to allow the ajoining cube to be
poured.

Didn't they also incorporate water cooling pipes?

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.