The wife doesn't look impressed...

http://www.bbc.co.uk/news/uk-england-19421332

--
David

gremlin_95 wrote:
The wife doesn't look impressed...

http://www.bbc.co.uk/news/uk-england-19421332

**** me. He dug a bomb up last week

http://www.bbc.co.uk/news/uk-england-devon-19358786

--
Adam

On Aug 30, 6:43*pm, "ARWadsworth"
wrote:
gremlin_95 wrote:
The wife doesn't look impressed...

http://www.bbc.co.uk/news/uk-england-19421332

**** me. He dug a bomb up last week

http://www.bbc.co.uk/news/uk-england-devon-19358786

--
Adam

While i was working for the NHS (Wales), we dug up a coal mine.
A cement truck and an excavator fell down it, about twenty feet.
Getting them out was a problem but nothing compared with getting the
concrete out of the truck, (it had set by then).
We needed around three hundred tons of hard core to fill the hole plus
concrete.
That was one job that went over budget. The NCB had to divvy up too.

The excavator driver righted the machine with the digger arm and was
set to dig his way out by digging a ramp. But he was persuaded to
stop. He was burying the cement truck anyway.
Nutter, there was no way of knowing how deep the hole was under him.
Welsh see?

harry wrote:
On Aug 30, 6:43 pm, "ARWadsworth"
wrote:
gremlin_95 wrote:
The wife doesn't look impressed...

http://www.bbc.co.uk/news/uk-england-19421332

**** me. He dug a bomb up last week

http://www.bbc.co.uk/news/uk-england-devon-19358786

Adam

While i was working for the NHS (Wales), we dug up a coal mine.
A cement truck and an excavator fell down it, about twenty feet.
Getting them out was a problem but nothing compared with getting the
concrete out of the truck, (it had set by then).
We needed around three hundred tons of hard core to fill the hole plus
concrete.
That was one job that went over budget. The NCB had to divvy up too.

My Dad might have been in charge of the NCB operations end of things:-)


The excavator driver righted the machine with the digger arm and was
set to dig his way out by digging a ramp. But he was persuaded to
stop. He was burying the cement truck anyway.
Nutter, there was no way of knowing how deep the hole was under him.
Welsh see?

Actually the NCB records are very good. Did it fall down a vertical shaft or
did if hit a seam that had been mined?

And what do kids do these days? We used to spend the summer holidays
climbing down old mine shafts in Fall Woods. No chance now as they are all
securely covered over. TBH they were covered over when we climbed down them
but we borrowed my Dad's socket set and removed the covers.

--
Adam

On 30/08/2012 19:32, ARWadsworth wrote:
harry wrote:

The excavator driver righted the machine with the digger arm and was
set to dig his way out by digging a ramp. But he was persuaded to
stop. He was burying the cement truck anyway.
Nutter, there was no way of knowing how deep the hole was under him.
Welsh see?
Actually the NCB records are very good. Did it fall down a vertical shaft or
did if hit a seam that had been mined?

And what do kids do these days? We used to spend the summer holidays
climbing down old mine shafts in Fall Woods. No chance now as they are all
securely covered over. TBH they were covered over when we climbed down them
but we borrowed my Dad's socket set and removed the covers.

Ha, classic



--
David

gremlin_95 wrote:
On 30/08/2012 19:32, ARWadsworth wrote:
harry wrote:

The excavator driver righted the machine with the digger arm and was
set to dig his way out by digging a ramp. But he was persuaded to
stop. He was burying the cement truck anyway.
Nutter, there was no way of knowing how deep the hole was under him.
Welsh see?
Actually the NCB records are very good. Did it fall down a vertical
shaft or did if hit a seam that had been mined?

And what do kids do these days? We used to spend the summer holidays
climbing down old mine shafts in Fall Woods. No chance now as they
are all securely covered over. TBH they were covered over when we
climbed down them but we borrowed my Dad's socket set and removed
the covers.

Ha, classic

They are not that secure. I bet I could get back down and cause no damage to
the covers.

--
Adam

On Aug 30, 7:32*pm, "ARWadsworth"
wrote:
harry wrote:
On Aug 30, 6:43 pm, "ARWadsworth"
wrote:
gremlin_95 wrote:
The wife doesn't look impressed...

http://www.bbc.co.uk/news/uk-england-19421332

**** me. He dug a bomb up last week

http://www.bbc.co.uk/news/uk-england-devon-19358786

Adam

While i was working for the NHS (Wales), we dug up a coal mine.
A cement truck and an excavator fell down it, about twenty feet.
Getting them out was a problem but nothing compared with getting the
concrete out of the truck, (it had set by then).
We needed around three hundred tons of hard core to fill the hole plus
concrete.
That was one job that went over budget. *The NCB had to divvy up too.

My Dad might have been in charge of the NCB operations end of things:-)



The excavator driver righted the machine with the digger arm and was
set to dig his way out by digging a ramp. But he was persuaded to
stop. He was burying the cement truck anyway.
Nutter, there was no way of knowing how deep the hole was under him.
Welsh see?

Actually the NCB records are very good. Did it fall down a vertical shaft or
did if hit a seam that had been mined?

And what do kids do these days? We used to spend the summer holidays
climbing down old mine shafts in Fall Woods. No chance now as they are all
securely covered over. TBH they were covered over when we climbed down them
but we borrowed my Dad's socket set and removed the covers.

--
Adam- Hide quoted text -

- Show quoted text -

The NCB records are crap. There is no record of many mines more than
100 yrs old. I remember there was a major accident a few years back
when miners broke into an unknown mine that was full of water. Can't
remember where it was.

It was a drift mine we "found" so there was no big hole under him as
it turned out. The collapse was slow motion, took about ten minutes.
Initially everyone thought is was just soft ground. As they tried to
get the mixer truck out with the digger they just gradually sunk
deeper and deeper.

On Aug 30, 7:32*pm, "ARWadsworth"
wrote:
harry wrote:
Still happening. This is a similar one but more recent than the one I
recall which was more serious..
http://www.bbc.co.uk/news/uk-wales-14968544

How do you get concrete out of one of those trucks after it has set? I
just assumed that you'd throw the mixing barrel away and buy a new one.

On Friday, August 31, 2012 10:01:13 AM UTC+1, GB wrote:
How do you get concrete out of one of those trucks after it has set? I

just assumed that you'd throw the mixing barrel away and buy a new one.

It must be scrap. Metal for recycling.
I always wondered what happened if a concrete mixer got stuck in a traffic jam. I wonder if its possible for a chemical to be added that prevents concrete from setting.
Simon.

In article ,
GB wrote:
How do you get concrete out of one of those trucks after it has set? I
just assumed that you'd throw the mixing barrel away and buy a new one.

Throw away? you'd have to be Superman to do that - it probably weighs 5 or
6 tons!

--
From KT24

Using a RISC OS computer running v5.18

On Aug 31, 7:08*am, harry wrote:
The NCB records are crap.

The NCB's records of the NCB are good, but records that had already
been lost before 1948 didn't miraculously reappear by the power of
collective ownership.

On Aug 31, 10:01*am, GB wrote:
How do you get concrete out of one of those trucks after it has set?

Depends on the economic situation. In a minor slump, you chip it out
because you have time and idle staff to do it. In a bad recession
you scrap the barrel, because you already own more trucks than you can
use. In a boom you scrap the barrel because it's quicker.

The barrel is offloaded at a scrapyard, because they're a pain to move
except by the truck they're already attached to. Then they're
scrapped by "peeling" the barrel off the concrete lump with an oxy
torch. The concrete lump is then often dumped (there used to be two
quite prominent ones in Liverpool, near the buoy in Everton, and it
got to the point where the history bus tours were referring to them as
"buoys" too). If you want to break the concrete, then it's usually
drilled and broken apart with a waterjel explosive, as the cheapest
way.

Andy Dingley wrote:

On Aug 31, 10:01*am, GB wrote:
How do you get concrete out of one of those trucks after it has set?

Depends on the economic situation. In a minor slump, you chip it out
because you have time and idle staff to do it. In a bad recession
you scrap the barrel, because you already own more trucks than you can
use. In a boom you scrap the barrel because it's quicker.

The barrel is offloaded at a scrapyard, because they're a pain to move
except by the truck they're already attached to. Then they're
scrapped by "peeling" the barrel off the concrete lump with an oxy
torch. The concrete lump is then often dumped (there used to be two
quite prominent ones in Liverpool, near the buoy in Everton, and it
got to the point where the history bus tours were referring to them as
"buoys" too). If you want to break the concrete, then it's usually
drilled and broken apart with a waterjel explosive, as the cheapest
way.

Just seen a Mythbusters episode where they looked at this.

They intended just to have a coating on the barrel, but instead
it was about 2/3 full.

Gradually increasing amounts of explosive did little more than
(eventually) loosen some of the surface coating.

They then took it to a remote quarry, filled it with a serious
amount of explosive, and retired to a safe distance.

The whole thing pretty well disintegrated - just a few bits of
chassis left identifiable.

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

sm_jamieson wrote:

I always wondered what happened if a concrete mixer got stuck in a traffic jam. I wonder if its possible for a chemical to be added that prevents concrete from setting.

A bag of sugar will retard setting to give you a chance to get
rid of the load.

http://www.concreteconstruction.net/...-retarder.aspx

Tests have shown that 0.05 percent (by weight of cement) of a refined granulated sugar included in a normal mix will retard setting by approximately 4 hours, increase the 7- and 28-day compressive strengths by about 8 percent, and give a more workable mix.

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

On Fri, 31 Aug 2012 11:55:54 +0100, Chris J Dixon wrote:

Andy Dingley wrote:

On Aug 31, 10:01Â*am, GB wrote:
How do you get concrete out of one of those trucks after it has set?

Depends on the economic situation. In a minor slump, you chip it out
because you have time and idle staff to do it. In a bad recession you
scrap the barrel, because you already own more trucks than you can use.
In a boom you scrap the barrel because it's quicker.

The barrel is offloaded at a scrapyard, because they're a pain to move
except by the truck they're already attached to. Then they're scrapped
by "peeling" the barrel off the concrete lump with an oxy torch. The
concrete lump is then often dumped (there used to be two quite prominent
ones in Liverpool, near the buoy in Everton, and it got to the point
where the history bus tours were referring to them as "buoys" too). If
you want to break the concrete, then it's usually drilled and broken
apart with a waterjel explosive, as the cheapest way.

Just seen a Mythbusters episode where they looked at this.

They intended just to have a coating on the barrel, but instead it was
about 2/3 full.

Gradually increasing amounts of explosive did little more than
(eventually) loosen some of the surface coating.

They then took it to a remote quarry, filled it with a serious amount of
explosive, and retired to a safe distance.

The whole thing pretty well disintegrated - just a few bits of chassis
left identifiable.

Chris

Very impressive bang. But I think the biggest was the attempt to make
diamonds, by putting 2.25 tonnes of ANFO on top of a pencil.

http://en.wikipedia.org/wiki/MythBus...emade_Diamonds

It was one of those blasts where you *see* the shockwave.

I wonder what the biggest non-accidental explosion in the UK has been.
Did anyone see the Richard Hammond recreation of the Gunpowder Plot ?

On 31/08/2012 11:55, Chris J Dixon wrote:

Just seen a Mythbusters episode where they looked at this.

They intended just to have a coating on the barrel, but instead
it was about 2/3 full.

Gradually increasing amounts of explosive did little more than
(eventually) loosen some of the surface coating.

They then took it to a remote quarry, filled it with a serious
amount of explosive, and retired to a safe distance.

The whole thing pretty well disintegrated - just a few bits of
chassis left identifiable.

ISTR something about blasting is you need to put enough bang in to
shatter the rock properly, and if you put too little in (or obviously
put it in too shallow) it makes more of a mess than the right amount.

I'm sure somebody will be along to correct that though :-)

On Fri, 31 Aug 2012 12:00:22 +0100, Chris J Dixon
wrote:

sm_jamieson wrote:

I always wondered what happened if a concrete mixer got stuck in a traffic jam. I wonder if its possible for a chemical to be added that prevents concrete from setting.

A bag of sugar will retard setting to give you a chance to get
rid of the load.

http://www.concreteconstruction.net/...-retarder.aspx

Tests have shown that 0.05 percent (by weight of cement) of a refined granulated sugar included in a normal mix will retard setting by approximately 4 hours, increase the 7- and 28-day compressive strengths by about 8 percent, and give a more workable mix.

That is fascinating. Though you have to wonder what happened to the
apprentice who first chucked a bag of sugar into the mix 'for a
laugh.'

Nick

On Aug 31, 1:37*pm, Clive George wrote:
ISTR something about blasting is you need to put enough bang in to
shatter the rock properly,

There are two sorts of blasting: blasting to make rocks and blasting
to make holes. If you're making holes, you might wish to "shatter"
the rock and create a volume of gravel. If you want rock, then you
break it with as few fractures as possible, until the boulders are
just small enough to move. The effect of an explosive, shattering vs.
fracturing, depends on its brissance, which depends on its chemistry
and how it's applied. As the energy of explosives required also
depends on the area of new surface created, it's _much_ easier to
break up a big lump into a few big pieces with a few long cracks than
it is to try and to shatter the lot. Explosives not terribly different
to gunpowder are still used for some high-value quarrying tasks,
because they're low brissance and they do so little shattering.

On Aug 31, 10:21*am, charles wrote:
In article ,
* *GB wrote:

How do you get concrete out of one of those trucks after it has set? I
just assumed that you'd throw the mixing barrel away and buy a new one.

Throw away? *you'd have to be Superman to do that - it probably weighs 5 or
6 tons!

If the drum can be kept revolving, it doesn't set into a big lump,
just lots of cement coated aggregate particles.

If it isn't discharged at site within and hour of mixing, it is dumped
as it will be way off specification.
They usually have some farmer somewhere that needs a track making up.

If the concrete has set in the drum but is still green it can be got
out relatively easily.

The drum has to be cleaned out annually, a cement coating has to be
removed. There is a hatch on the side of the drum for access, someone
has to get inside with a jackhammer.
I had lots of concrete a couple of years back & I asked the drivers
about all this.

In message
,
harry writes
On Aug 31, 10:21*am, charles wrote:
In article ,
* *GB wrote:

How do you get concrete out of one of those trucks after it has set? I
just assumed that you'd throw the mixing barrel away and buy a new one.

Throw away? *you'd have to be Superman to do that - it probably weighs 5 or
6 tons!

If the drum can be kept revolving, it doesn't set into a big lump,
just lots of cement coated aggregate particles.

If it isn't discharged at site within and hour of mixing, it is dumped
as it will be way off specification.
They usually have some farmer somewhere that needs a track making up.

If the concrete has set in the drum but is still green it can be got
out relatively easily.

The drum has to be cleaned out annually, a cement coating has to be
removed. There is a hatch on the side of the drum for access, someone
has to get inside with a jackhammer.
I had lots of concrete a couple of years back & I asked the drivers
about all this.

Along similar lines... I had a barn underpinned with 10 roughly 1m cubed
hand mixed concrete pads.

2 of these were a little too high and I accepted an offer to *gun* off
the top 50mm while they were still green. Recently, while I was doing
some further flooring work, I discovered that the tops of these pads are
*biscuity* and that chunks of aggregate and crumbs of sand can be broken
away with the fingers!

Presumably the vibration has interfered with the setting process in some
way.

regards

--
Tim Lamb

On 31/08/2012 13:10, Jethro_uk wrote:

I wonder what the biggest non-accidental explosion in the UK has been.
Did anyone see the Richard Hammond recreation of the Gunpowder Plot ?

Was that on Brainiac Science Abuse? I rather liked the propane?/air mix
in a balloon the put inside a caravan as a powerful no-nonsense method
of destruction!

Jethro_uk wrote:
On Fri, 31 Aug 2012 11:55:54 +0100, Chris J Dixon wrote:

Andy Dingley wrote:

On Aug 31, 10:01 am, GB wrote:
How do you get concrete out of one of those trucks after it has set?
Depends on the economic situation. In a minor slump, you chip it out
because you have time and idle staff to do it. In a bad recession you
scrap the barrel, because you already own more trucks than you can use.
In a boom you scrap the barrel because it's quicker.

The barrel is offloaded at a scrapyard, because they're a pain to move
except by the truck they're already attached to. Then they're scrapped
by "peeling" the barrel off the concrete lump with an oxy torch. The
concrete lump is then often dumped (there used to be two quite prominent
ones in Liverpool, near the buoy in Everton, and it got to the point
where the history bus tours were referring to them as "buoys" too). If
you want to break the concrete, then it's usually drilled and broken
apart with a waterjel explosive, as the cheapest way.
Just seen a Mythbusters episode where they looked at this.

They intended just to have a coating on the barrel, but instead it was
about 2/3 full.

Gradually increasing amounts of explosive did little more than
(eventually) loosen some of the surface coating.

They then took it to a remote quarry, filled it with a serious amount of
explosive, and retired to a safe distance.

The whole thing pretty well disintegrated - just a few bits of chassis
left identifiable.

Chris

Very impressive bang. But I think the biggest was the attempt to make
diamonds, by putting 2.25 tonnes of ANFO on top of a pencil.

http://en.wikipedia.org/wiki/MythBus...emade_Diamonds

It was one of those blasts where you *see* the shockwave.

I wonder what the biggest non-accidental explosion in the UK has been.
Did anyone see the Richard Hammond recreation of the Gunpowder Plot ?


Heligoland
On 18 April 1947 British engineers attempted to destroy the entire
North Sea island of Heligoland in what became known as the "British
Bang".[citation needed] Roughly 4000 tons[27][28] of surplus World War
II ammunition were placed in various locations around the island and set
off. The island survived, although the extensive fortifications were
destroyed. According to Willmore,[28] the energy released was 1.3×1020
erg (1.3×1013 J), or about 3.2 kilotons of TNT equivalent. The blast is
listed in the Guinness Book of World Records under largest single
explosive detonation, although Minor Scale would appear to be larger.

--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

On Sat, 01 Sep 2012 01:07:46 +0100, The Natural Philosopher
wrote:



Heligoland
On 18 April 1947 British engineers attempted to destroy the entire
North Sea island of Heligoland in what became known as the "British
Bang".[citation needed] Roughly 4000 tons[27][28] of surplus World War
II ammunition were placed in various locations around the island and set
off. The island survived, although the extensive fortifications were
destroyed. According to Willmore,[28] the energy released was 1.3×1020
erg (1.3×1013 J), or about 3.2 kilotons of TNT equivalent. The blast is
listed in the Guinness Book of World Records under largest single
explosive detonation, although Minor Scale would appear to be larger.

Was one of the subjects on Coast a while back. Impressive damage.

--
Rod

On Sat, 01 Sep 2012 01:07:46 +0100, The Natural Philosopher
wrote:

I wonder what the biggest non-accidental explosion in the UK has been.
Did anyone see the Richard Hammond recreation of the Gunpowder Plot ?


Heligoland
On 18 April 1947 British engineers attempted to destroy the entire
North Sea island of Heligoland in what became known as the "British
Bang".[citation needed] Roughly 4000 tons[27][28] of surplus World War
II ammunition were placed in various locations around the island and set
off. The island survived,


Ironical that when that was done some of the displaced islanders were
old enough to have been British subjects when they were young.
and some possibly could still be British citizens if they or their
parents had opted to retain it before 1892. Some did make
representations to Britain but were ignored ,so rather than establish
relations with a group of people whose inclination to Britain was
friendly their attitude was turned around to an extent that British
visiting the Island are still treated coolly today. It's not an
outright hostility,feels similar to being the only English person in a
pub full of Welsh speakers.
Still the war department treated some people in this country equally
badly, the residents of Imber and Tyneham never got their homes back
as promised.

G.Harman

On Thu, 30 Aug 2012 19:32:03 +0100, "ARWadsworth"
wrote:

And what do kids do these days? We used to spend the summer holidays
climbing down old mine shafts in Fall Woods. No chance now as they are all
securely covered over. TBH they were covered over when we climbed down them
but we borrowed my Dad's socket set and removed the covers.

A mate of mine was out in the Aussie goldfields near Calgoorlie (iirc)
and it's reckoned the number of lost bodies down abandoned shafts in
the middle of nowhere is impossible to estimate.

On Fri, 31 Aug 2012 14:03:19 +0100, Nick Odell
wrote:

Tests have shown that 0.05 percent (by weight of cement) of a refined granulated sugar included in a normal mix will retard setting by approximately 4 hours, increase the 7- and 28-day compressive strengths by about 8 percent, and give a more workable mix.

That is fascinating. Though you have to wonder what happened to the
apprentice who first chucked a bag of sugar into the mix 'for a
laugh.'

You'd also wonder what happened to the load of concrete that had sugar
lobbed into it that nobody knew about - collapsing school swimming
pool roofs?

On Sat, 01 Sep 2012 11:33:17 +0100, Grimly Curmudgeon
wrote:

On Fri, 31 Aug 2012 14:03:19 +0100, Nick Odell
wrote:

Tests have shown that 0.05 percent (by weight of cement) of a refined
granulated sugar included in a normal mix will retard setting by
approximately 4 hours, increase the 7- and 28-day compressive
strengths by about 8 percent, and give a more workable mix.

That is fascinating. Though you have to wonder what happened to the
apprentice who first chucked a bag of sugar into the mix 'for a
laugh.'

You'd also wonder what happened to the load of concrete that had sugar
lobbed into it that nobody knew about - collapsing school swimming
pool roofs?

Don't think that follows from what has been written. We might assume
increased compressive strength on a long term basis - but the retarded
setting would only affect the builders in most cases, surely?

--
Rod

On Sat, 01 Sep 2012 12:01:13 +0100, polygonum
wrote:

Tests have shown that 0.05 percent (by weight of cement) of a refined
granulated sugar included in a normal mix will retard setting by
approximately 4 hours, increase the 7- and 28-day compressive
strengths by about 8 percent, and give a more workable mix.

That is fascinating. Though you have to wonder what happened to the
apprentice who first chucked a bag of sugar into the mix 'for a
laugh.'

You'd also wonder what happened to the load of concrete that had sugar
lobbed into it that nobody knew about - collapsing school swimming
pool roofs?

Don't think that follows from what has been written. We might assume
increased compressive strength on a long term basis - but the retarded
setting would only affect the builders in most cases, surely?

That finding up top comes as a surprise, for I'm sure I've read that
sugar content reduces strength and/or longevity; perhaps it does in
more uncontrolled amounts.

On Sat, 01 Sep 2012 12:14:13 +0100, Grimly Curmudgeon
wrote:

On Sat, 01 Sep 2012 12:01:13 +0100, polygonum
wrote:

Tests have shown that 0.05 percent (by weight of cement) of a
refined
granulated sugar included in a normal mix will retard setting by
approximately 4 hours, increase the 7- and 28-day compressive
strengths by about 8 percent, and give a more workable mix.

That is fascinating. Though you have to wonder what happened to the
apprentice who first chucked a bag of sugar into the mix 'for a
laugh.'

You'd also wonder what happened to the load of concrete that had sugar
lobbed into it that nobody knew about - collapsing school swimming
pool roofs?

Don't think that follows from what has been written. We might assume
increased compressive strength on a long term basis - but the retarded
setting would only affect the builders in most cases, surely?

That finding up top comes as a surprise, for I'm sure I've read that
sugar content reduces strength and/or longevity; perhaps it does in
more uncontrolled amounts.

You might very well be right - seems to be something that, ideally, would
get followed up here. Maybe strength goes up for a month then falls? Or
perhaps true long-term it enables/causes different ways of failing?

Wondering if it would have any effect on growth of moulds? But suspect the
absolute quantity is too low to be significant.

--
Rod

"Grimly Curmudgeon" wrote in message
...
On Thu, 30 Aug 2012 19:32:03 +0100, "ARWadsworth"
wrote:

And what do kids do these days? We used to spend the summer holidays
climbing down old mine shafts in Fall Woods. No chance now as they are all
securely covered over. TBH they were covered over when we climbed down
them
but we borrowed my Dad's socket set and removed the covers.

A mate of mine was out in the Aussie goldfields near Calgoorlie (iirc)
and it's reckoned the number of lost bodies down abandoned shafts in
the middle of nowhere is impossible to estimate.

25.
There you are its not impossible at all.

Now if you want an accurate figure...

On Sat, 01 Sep 2012 20:45:58 +0100, John Williamson
wrote:

Grimly Curmudgeon wrote:
On Fri, 31 Aug 2012 14:03:19 +0100, Nick Odell
wrote:

Tests have shown that 0.05 percent (by weight of cement) of a
refined granulated sugar included in a normal mix will retard
setting by approximately 4 hours, increase the 7- and 28-day
compressive strengths by about 8 percent, and give a more workable
mix.
That is fascinating. Though you have to wonder what happened to the
apprentice who first chucked a bag of sugar into the mix 'for a
laugh.'
You'd also wonder what happened to the load of concrete that had sugar
lobbed into it that nobody knew about - collapsing school swimming
pool roofs?

That was fast setting concrete that turned out not to be chlorine
resistant. The combination of the chlorine and the damp air from the
swimming pools acting on the accelerator caused the cement to crumble,
leaving the aggregate held together by, well, nothing useful, really.

I'd love to know if it's a similar problem causing the M4 elevated
section and the Hammersmith flyover to be crumbling now, as they've been
throwing salty water at them for a few decades and they were built at
about the same time as the collapsing pool roofs, or if it's just a case
of insufficient cover and the reinforcement rusting, blowing the
concrete off.

I noticed abroad (Abu Dhabi) that all the reinforcement seemed to be
coated before use - a sort of greenish appearance. Have always assumed
that was to avoid rusting and the consequences thereof. And wondered why
we do not do so?

--
Rod

On 31/08/2012 10:16, sm_jamieson wrote:
On Friday, August 31, 2012 10:01:13 AM UTC+1, GB wrote:
How do you get concrete out of one of those trucks after it has set? I

just assumed that you'd throw the mixing barrel away and buy a new one.

It must be scrap. Metal for recycling.

During a summer job I once had to spend the best part of a day inside
the barrel of one of those mini-mixers, equipped with club hammer, cold
chisel and - most important - ear defenders...

David

In message , ARWadsworth
writes
gremlin_95 wrote:
The wife doesn't look impressed...

http://www.bbc.co.uk/news/uk-england-19421332

**** me. He dug a bomb up last week

http://www.bbc.co.uk/news/uk-england-devon-19358786

Proper little ferret isn't he

--
geoff

In message
,
harry writes
On Aug 30, 6:43*pm, "ARWadsworth"
wrote:
gremlin_95 wrote:
The wife doesn't look impressed...

http://www.bbc.co.uk/news/uk-england-19421332

**** me. He dug a bomb up last week

http://www.bbc.co.uk/news/uk-england-devon-19358786

--
Adam

While i was working for the NHS (Wales), we dug up a coal mine.

Did you write a lonely planet guide for it?


--
geoff

In message , GB
writes
How do you get concrete out of one of those trucks after it has set? I
just assumed that you'd throw the mixing barrel away and buy a new one.


Its one of Harry's stories

just smile and move on


--
geoff

Andy Dingley wrote:
On Aug 31, 7:08 am, harry wrote:
The NCB records are crap.

The NCB's records of the NCB are good, but records that had already
been lost before 1948 didn't miraculously reappear by the power of
collective ownership.

The NCB's records are excellent. I have seen them.

My Dad was in charge of the Yorkshire records and in charge of writing out
cheques for people who suffered subsidence damage.

He was a bit of a ****. When a housing estate was about to be underminned he
used to go out before they undermined it and photograph all the cracked
walls and driveways. He used the photos as evidence when the owners later
tried to make a subsidence claim (and most people in South Yorks used to
make a claim).


--
Adam

On Sep 2, 5:33*pm, geoff wrote:
In message
,
harry writes

On Aug 30, 6:43*pm, "ARWadsworth"
wrote:
gremlin_95 wrote:
The wife doesn't look impressed...

http://www.bbc.co.uk/news/uk-england-19421332

**** me. He dug a bomb up last week

http://www.bbc.co.uk/news/uk-england-devon-19358786

--
Adam

While i was working for the NHS (Wales), we dug up a coal mine.

Did you write a lonely planet guide for it?

--
geoff


No, we smashed it all down, compacted it and filled with hard core.

On Sep 2, 5:43*pm, geoff wrote:
In message , GB
writesHow do you get concrete out of one of those trucks after it has set? I
just assumed that you'd throw the mixing barrel away and buy a new one.

Its one of Harry's stories

just smile and move on

--
geoff

You must have a boring life.

In message
,
harry writes
On Sep 2, 5:33*pm, geoff wrote:
In message
,
harry writes

On Aug 30, 6:43*pm, "ARWadsworth"
wrote:
gremlin_95 wrote:
The wife doesn't look impressed...

http://www.bbc.co.uk/news/uk-england-19421332

**** me. He dug a bomb up last week

http://www.bbc.co.uk/news/uk-england-devon-19358786

--
Adam

While i was working for the NHS (Wales), we dug up a coal mine.

Did you write a lonely planet guide for it?

--
geoff


No, we smashed it all down, compacted it and filled with hard core.

What, the lonely planet guide ?


--
geoff