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Rollingthunder
9th Oct 2011, 18:29
BIG BEN....

Civil engineers have found that the clock tower at the Palace of Westminster is no longer ramrod straight and the problem is getting worse every year. The top of the tower is now almost one-and-a-half feet off the perpendicular. If left uncorrected it would eventually fall.

Mechta
9th Oct 2011, 18:33
Hardly surprising with all those bent politicians in close proximity; it must be contagious.

G-CPTN
9th Oct 2011, 18:47
at its current speed it would take some 4,000 years to reach the angle of the Leaning Tower of Pisa, and even longer to hit tipping-point.
From:- Bong! Big Ben becoming leaning tower of London, say engineers - Telegraph (http://www.telegraph.co.uk/news/newstopics/howaboutthat/8815238/Bong-Big-Ben-becoming-leaning-tower-of-London-say-engineers.html)

ZOOKER
9th Oct 2011, 18:55
I would just like to point out, (as someone eventually will), that 'Big Ben' is actually the extremely large cracked bell which chimes the hour.
The leaning structure, within in which 'big Ben' resides is known variously as either:-
St. Stephen's Tower, or
The Clock Tower of the Palace Of Westminster.

Carry on..........

Cacophonix
9th Oct 2011, 18:55
As a math fan, I ask you can we deal with the Tower of Hanoi...

aGlt2G-DC8c

Mike aka (Caco)

west lakes
9th Oct 2011, 19:14
Interesting!
Some may have heard of Blackpool Tower which is in excess of 500ft high. A little known fact is that it was built leaning slightly towards the sea in the hope that if it ever did collapse it would fall onto the beach rather than the town

Lon More
9th Oct 2011, 19:38
if it ever did collapse it would fall onto the beach rather than the town

wasted opportunity for a bit of much needed urban renewal. The same could be said for the Clock Tower of the Palace of Westminster and the New Tower at Heathrow.

ZOOKER
9th Oct 2011, 20:02
Does that mean the collapse of Blackpool Tower would demolish the 2.7m wooden
'wedding chapel' that has been built on the promenade* this year?

*Abeam where Lewis's department store was for those who know the area.

No, I am not joking, honestly. I've seen it, it's real.

west lakes
9th Oct 2011, 20:06
Does that mean the collapse of Blackpool Tower would demolish the wooden
'wedding chapel' that has been built on the promenade* this year?

Probably, it certainly would make a mess of the new promenade surfacing

Capetonian
9th Oct 2011, 20:13
If that bell fell into the Chamber of Commons it would just add one more massive clanger to those that take place there every day.

Tankertrashnav
10th Oct 2011, 00:10
I got on a conducted tour of the Palace of Westminster once, which included a trip to the top of the clock tower. This was timed to arrive at the top just before midday to give you the experience of hearing Big Ben strike at very close quarters. Made the fillings vibrate!

The clock mechanism fills a large room, and is driven by huge weights which hang down inside the tower. The time is adjusted by adding or taking away one coin from a small stack of old pennies which sit on the top of the pendulum. I had the opportunity of nicking one of the pennies, but as there is a prison cell at the base of the tower I thought better of it.

Glad I did it 20 years ago - not sure I'd hack the 334 steps to the top now :(

parabellum
10th Oct 2011, 03:23
And suppose you had nicked the penny and it turned out to be a 1933 one?!;)

hellsbrink
10th Oct 2011, 05:17
How much of this "tilt" is due to the tunnels for the Jubilee Line? I remember there being a rather large issue as they built the extension, with the tower having to be shored up, etc, and tonnes of concrete poured into the ground under the tower to stabilise it......

Storminnorm
10th Oct 2011, 11:54
As far as I'm concerned it's just another reason to
avoid going to London. Bl**dy dump!!!

It's a pity they don't seal off all the access roads from London
to the M 25. Just build a BIG wall inside it, and leave the place
to fester in it's own excrement.

BOAC
10th Oct 2011, 13:15
Urgent - 'Call me Dave' wants to know if it is leaning to the left or right..................

603DX
10th Oct 2011, 14:02
How much of this "tilt" is due to the tunnels for the Jubilee Line? I remember there being a rather large issue as they built the extension, with the tower having to be shored up, etc, and tonnes of concrete poured into the ground under the tower to stabilise it......


You may have put your finger on it, hellsbrink. The tower was built on a relatively shallow concrete foundation bearing on the alluvial deposits known as Thames Ballast, a mixture of sand and gravel spread there by the river over many years. This natural stratum tends to be very variable in grading, density, and safe bearing capacity, and the foundations of many public buildings along the banks of the Thames have had to be very carefully designed (and constructed) to take account of this variability. This particular tower actually started to lean slightly soon after it was built, back in the mid 1800's, and this was not particularly unusual. Later construction work near existing foundations has been known to disturb equilibrium to some degree, necessitating special techniques like cement grout injections, for example. Even with such measures, some movement is still possible. In this case, the problem was complex:

The Jubilee Line Extension (http://www-g.eng.cam.ac.uk/125/noflash/now/jubilee2.html)

The Westminster tube station modifications for the Jubilee Line extension work could perhaps be a contributory factor in the slight tilting, but I am sure that the matter is well under control and being meticulously monitored. :)

MagnusP
10th Oct 2011, 15:09
Hmm. Let's see. Damp sand and gravel + vibration. Liquefaction, anyone?

603DX
10th Oct 2011, 15:37
Might contribute a smidgen (note technical term, please!), but my own experience of the Thames Ballast layer in central London leads me to doubt it. The sand is generally of coarse grading, has more "sharp" than "rounded" grains, and usually occurs with significant gravel content. Not the sort of material prone to liquefaction, in my humble opinion. The running tunnels are a fair distance away in the blue London Clay, and the vibration levels are not likely to be particularly severe with modern running stock and rails.

Storminnorm
10th Oct 2011, 15:42
So, basically, the Tower is just falling down on it's own then?

G-CPTN
10th Oct 2011, 15:51
LtuV_mB88cc

Ani fule kno that!

603DX
10th Oct 2011, 16:15
So, basically, the Tower is just falling down on it's own then?

Well, nobody's pushing it as far as I know Norm, so yup! It'll probably outlast us all, and then some, even if no-one does a damned thing about it. There are two of the most eminent and respected geotechnical specialists in the world, Professors Robert Mair and John Burland on the case, so I think the MP's across the road in Portcullis House are pretty safe (unfortunately). ;)

G-CPTN
10th Oct 2011, 16:48
On the subject of the longevity of public buildings, these obviously have a useful life, beyond which they are no longer sustainable.
I mention this because there are few (other than churches) that have survived beyond 1000 years (and even they have probably been modified in the meanwhile), so how long should we expect the Houses of Parliament (and the tower containing Big Ben) to survive?

The current buildings are a mere 170 years or so old (how did they manage between 1834 and 1870?) so how long can they be sustained, even given that they are Grade 1 listed?

The first royal palace was built on the site in the eleventh century, and Westminster was the primary London residence of the Kings of England until a fire destroyed much of the complex in 1512. After that, it served as the home of Parliament, which had been meeting there since the thirteenth century, and the seat of the Royal Courts of Justice, based in and around Westminster Hall.
In 1834, an even greater fire ravaged the heavily rebuilt Houses of Parliament, and the only structures of significance to survive were Westminster Hall, the Cloisters of St Stephen's, the Chapel of St Mary Undercroft and the Jewel Tower.

In this instance, the subject is a building of national significance (and importance?), but the general question remains about the life of buildings?

Maybe because the areas are fully built-up means that we are forced to protect the existing structures? (or are we enduring a period of emotional attachment to a particular period of our national history?)

Do the Chinese (for example) continue using buildings that are (several) hundred years old? I believe that some of their heritage structures (apart from the Great Wall) are regularly demolished and rebuilt in the same style (though I remain open to contradiction on this). What about India?

What is it about our desire to hang on to structures that are inefficient - just because they are old?

As mentioned earlier in the thread, the current rate of lean of the clock-tower should see it still standing (although leaning) in 4000 years time.

Will it have been replace with a digital timepiece before then? (or will public clocks be redundant as by then everyone will carry their own devices that will accurately report the time?)

Of course, when our government is replaced by Brussels - or was it Strasbourg? . . .

. . . there will be no need for the Houses of Parliament . . .

Krystal n chips
10th Oct 2011, 17:50
So, that would be one full chamber....one decent earthquake....and... bingo ! :E

Purely a hypothesis.....alas.

hellsbrink
10th Oct 2011, 18:08
Will it have been replace with a digital timepiece before then?

Back in 1999 I had some tourists (Murrican, Japanese and Italian) convinced that the clock was going to be changed for a digital one in time for the Millennium..................


Well, it worked until I realised they completely believed every word I said and I got the giggles.........

603DX
10th Oct 2011, 23:18
G-CPTN raises the subject of the longevity expected of public buildings, which ranks with the age-old question "How long is a piece of string?", and is virtually as impossible to quantify. It all depends on a multitude of factors, some of which change over the years, so it can be a moving target.

Until relatively recent times, it was almost unknown for specific figures to be laid down for the projected life expectancy of major public buildings. If it was thought about at all, vague expectations like "As long as possible" or even the unrealistic "For ever" might be expressed. Often those involved in the conception, planning and construction phases of large projects preferred not to think about it at all.

Assuming that the building is not universally hated from the outset, and becomes "iconic" from sheer familiarity in a prime location as time passes, a major variable affecting its life is the quality of materials used. Barry chose a type of magnesian limestone which weathered and eroded badly, so needed extensive repair and replacement work on the exterior of the Parliament buildings. This is very time consuming and expensive, and is likely to require ongoing attention for a very long time. So it's just as well that the public seem to like the monstrous pile, it may have its life prolonged indefinitely as a result. The attached Westminster Hall is 900 years old, and has had much structural renovation to achieve that venerable age, so there's a target to aim for .... or not, as political and demographic changes occur, maybe.

More modern buildings like the National Theatre on the South Bank have received mixed reactions from the public (Prince Charles hates it, for one), and it was designed in reinforced and prestressed concrete and steelwork to a projected nominal design life of 120 years. This doesn't mean it will be demolished and replaced in about the year 2096, its detractors will be disappointed to hear, the life could easily be extended if by then it has become "loved" by the masses. But don't hold your breath ....

Loose rivets
11th Oct 2011, 00:03
When I got married we took a company freebie to Piza and climbed to the top of the tower. I became preoccupied with a young girl's beauty, and below, some girls of the night - obviously out early - became preoccupied with the Rivetess' mini skirt. They all laughed in amazement at the daringness of a 60's Brit.

Just colouring the picture a bit.

Thing was, it really did tilt. I mean, grip-the-pillars-on-the-down-side-and-stare-with-wide-eyes, kind of really tilt. No significant mortar, just nicely crafted stones. Cosign of the angle of dangle and all that.

Then there's the Naze tower at Walton on the Naze. I thought I was the only one that noticed it leaned, but sipping me wine at an invited art thing at the tower, a builder told of how his guys used to avoid transiting the east side when going for materials.

My pal and I busted into it in the 50s, so all a bit old hat for us.

Lot's on giggle about it. Radar station in the war etc. See Putman's site of old Walton.

When I were a kid, it were miles - ney, hundreds of feet - from the sea. Now, it's likely to topple over the 70' cliffs within my lifetime. Well, that's next week then. :(

It has an amazing history. Trinity House built it, and it was used for proper things in them days. Getting ships into Harwich and Parkstone, and keeping them off the rocks and masses of sandbanks off this part of the Essex coast. However, like the Hellfire Caves, it took on a darker use.

Shenanigans took place...and why not? Fine upstanding Piers of the realm would do what Piers of the realm did, and they seemed to do it well in the polygonal redbrick tower. Sadly, a vicar took a shine to a theatrical lady. Sadly for him that is.

He met her outside a London theater, but so did that Pier of the realm. So incensed was the vicar, that he took out his Webly, and shot her dead. Probably a nano-second after she thought, 'Bugger!' he thought the same thing, because he was hauled off, and hanged by the appropriate part.

Anyway, looking up the Naze Tower is a worthwhile pastime. I've even found it entertaining in my dotage.

The wife of a lifelong friend was coming up the iron spiral staircase to her husband's art exhibition. I leaned down to greet her, and when she recognized me, she said, "Oh, you look different from underneath."

Needless to say, I couldn't resist it. "All the girls say that." I didn't crack the slightest smile.

Lot of wine spluttered at that showing. Well, it's what old friends are for.

One has said, one will travel from any place in the world to see it topple over the cliff. All the pill boxes we played int are seventy feet below on the sands. Just a matter of time.

Naze Tower, Walton on the Naze, Essex (http://www.nazetower.co.uk/tower_museum.html)

G-CPTN
11th Oct 2011, 00:08
Having watched a few domestic dwellings being built over the last couple of years, it appears that 'building regulations' now require 4 to 5 inches of underfloor insulation to be installed to minimize heat-loss to the underlying ground.

I don't know whether such requirements apply to buildings such as churches.
(what about those burials - would they have to be above the insulation?)

G-CPTN
11th Oct 2011, 00:18
From Wiki about the Naze Tower:- Built in 1720 by Trinity House as a Navigation Mark. Originally half a mile inland. Now only 60 m from sea because of falling cliff faces. Has got approx 20 years before it falls into the sea.

Loose rivets
11th Oct 2011, 00:25
Well found, Mr GC . . . but buggah! It sounds as though it will outlive me.

603DX
11th Oct 2011, 00:47
Get away, LR, don't be such a pessimist! I'm the same age as you, and determined to get back a decent return on all the years of pension contributions - 92 years old is nothing, nowadays, I'm going for the century! ;)