Lock pics

[damo]

I have come across some pics of the Portishead lock - one of the deepest in the Europe, if not the world! If you got your tide times wrong then this is what you might see /forums/images/graemlins/smile.gif

(NB His feet are at 3.0m aCD, and you can see why you may be asked to go portside-to if it is the last lock of a tide)

And this is an aerial view from 1950, when the power station and phosphorus plant were in full-swing

 

[Csail]

Why is it sloping, can only assume to flow the mud away?

 

[damo]

That may be part of it, but I think it is mainly due to the fact that the right wall is the original stone and there is an engineering reason to brace the foot of it. Looking the other way you can see how the base of the old outer lock barrel is curved:

 

[Elza_Skip]

Fascinating, however I think Sharpness is more daunting- Not sue if it is deeper but it's huge as well! /forums/images/graemlins/shocked.gif

 

[LizzyD]

nice one Damo. I love this engineering stuff. It's absolutely fascinating. I don't know how these people have the imagination and innovation to dream these things up. Right, after yesterdays rugby fest, I'm off to watch the Jocks and Frogs.

Take care all,


Lizzy D

 

[Sneds]

Yea, interesting photos Damo, thanks.
No one over here (England) has mentioned the rugby all day!

 

[mrbloto]

i wonder why /forums/images/graemlins/laugh.gif /forums/images/graemlins/laugh.gif /forums/images/graemlins/laugh.gif

 

[donm]

It was common practice in masonry gravity retaining walls to progressively thicken the wall from the top to the bottom, resulting in a heavy load which needed to be spread over a greater area of the foundation. The land side of the masonry wall is probably stepped out as it goes deeper and is likely to be 4 or 5 times thicker than the concrete wall to the other side. More modern reinforced concrete structures are much more efficiently designed as reinforced concrete is inherently stonger than bonded masonry, so the wall can be thinner and lighter and consequently need less foundation area.

But although this may be the case, it might also be that it was built as way of shedding the mud to one side!

 

[damo]

Within the marina itself, the old quayside stone wall has been retained along one side, with new construction very close. Marina water levels need to be maintained above a certain height so the masonry wall gets enough support. Supposedly there is a danger of collapse if the level gets too low.

 

[Jobs_a_ good_ un]

Thats a baby this is the deepest lock in europe 23 m

 

[Csail]

So where do you tie on?????

 

[Jobs_a_ good_ un]

The French have sliding bollards that go up and down with the flow of the lock very efficient they are to
That lock is on the rhone the largest one in Europe at 23 m
Then you go under the guillitine to exit that bits a bit nerve racking

 

[damo]

Re: Lock pics - especially for LizzyD

Portishead Marina Lock

The lock is 43 x 9.3m, with a capacity of just under 1 million galls, or 4500 Tonnes of
water. A complete emptying of the lock will lower the marina impound level by 50mm.
The new floor of the lock was designed to prop the walls apart, and a total of 9000 cubic
metres of concrete and 1000T of rebar was used.

The gates are quadrant sector gates, and at 13.3m high are believed to be the tallest in
the world. The 4 gates each have 2No phosphor bronze hinge pins, which are 3m long and
360mm in diameter. The gates weigh 78T each, each operated by a single ram developing
237T thrust.

The 2 75kW impound pumps for maintaining marina levels each weigh 1 T, have a diam of
700mm, and can shift 750 litres/second each. The annual electricity cost is classified /forums/images/graemlins/smile.gif

 

[Elza_Skip]

Re: Lock pics - especially for LizzyD

Quite some stats, but when we locked through Sharpness last summer, the lock was broken and they had to use the whole tidal basin for just our little boat.

Now there's a few million gallons!

 

[graham]

Cardiff Barrage Lock

Cardiff Barrage Lock. Dont know the dimensions but as it covers the whole range of the tide it must be fairly deep.

 

[damo]

Re: Cardiff Barrage Lock

Lock 1 is 36 x 10.5m, Locks 2 and 3 are 36 x 8m. The inner sills can vary in height depending on salinity levels. The gates are reported to be 16m high which makes them the highest!

(I was looking for images, and found a site with pics of Felice Varini's yellow stripes on the Barrage locks. There is some STUNNING photoart