Broads Authority Briefing September 2019

[JennyMorgan]

9 hours ago, grendel said:

surely something like that would have been reported in the survey, it was after all only someones opinion that they though it might have sunk on one side, it could of course easily been an optical illusion caused by the angle of viewpoint.

It is very easy to just pick and choose the bits of a post that we would like to believe, but we have now seen the sea levels data and the bridge survey, so if the bridge isnt sinking, and the sea hasnt risen as much as the clearance has dropped, that just leaves "something else" as the cause, once the known causes have been deducted.

as for one side sinking, the picture in the report does show one arch lower than the other, but then again so does this one from 1926, clearly the herbert woods side arch is lower than the other, and yes there does appear to be more clearance in 1926 than 2011, but then sea level in 1926 was some 75mm below average UK MSL whereas in 2011, it was 100mm above UK MSL, a difference 0f 175mm.

It's down to the curvature of the earth. I often wonder what foundation that bridge has, if any.

[ExSurveyor]

If the bridge was sinking it would have started after it was built, 635 years later it would be under water.

The foundations of these medieval bridges were, on the whole, very impressive.

In Rochester, when they removed the medieval bridge 100 years ago, the Royal Engineers couldn't destroy the old foundations even with lots of explosives.

 

 

[Timbo]

The usual medieval bridge foundation construction consisted of a considerable amount of wooden piling driven into the clay in a pattern of wide concentric circles. The pilings would be connected by joists and the whole structure would then be packed tight with local stones or gravel. This would then be planked with oak or elm before the stone piers and abutments were constructed on top of this structure. I've excavated three medieval bridges, and as Mark says about Rochester, the pilings and foundations are 'monumental' in the true sense of the word.

Potter Heigham, or Repps, Bridge is a bit of a belt and braces affair due to the episodes of construction, demolition and restoration of the current structure over it's 751 years of its current iteration. Looking at the cut-waters on the side arches you will notice that they are each of different construction. The side arches themselves I would put an earlier date of 13th century rather than than the 14th of the scheduling. I would surmise that reworking of the piers and abutments of the side arches was carried out in the 15th century when the 'pointed' central span was replaced with the current circular arch. Casting a wider eye over the approaches to the bridge and the projection of the springing line, with little variation in extrados and intrados of the central span would back this.

There is 'movement' in the bridge structure, but this is to splay horizontally and not vertically. This is evidenced, as Alan pointed out, in both the spandrels, the discovery of the original parapet on the river bed, the 18th century replacement parapet and the addition of cantilever buttresses at the same time. This is the 'belt and braces' I was referring to. Medieval architecture has as much to do with form as it does structure. For example, many of our cathedrals are built on foundations of little more than a few inches of compacted chalk and gravel and a thousand years later they are still there.

 

[vanessan]

Now that’s what I call a belt and braces explanation! Thank you Timbo, I shall never look at PH bridge in the same way again - it deserves much more respect. (And to be left as it is!)

[TheQ]

On ‎28‎/‎09‎/‎2019 at 07:52, SPEEDTRIPLE said:

Leave it on the bank for wildlife to make use of. Down here in the West Moors Plantation, the Foerestry Commission cut down some trees and leave them on the ground to do just that, and they eventually get covered in moss and stuff, or eventually rot down to create habitat or a food source for bugs etc which birds etc feed on, and so on.  

 

The problem with that is that many species will regrow from a piece left on the ground particularly willow..

[marshman]

It would make life a whole lot easier if the BA actually controlled it all - but at the end of the day, thats the landowners decision.

[JennyMorgan]

4 minutes ago, marshman said:

It would make life a whole lot easier if the BA actually controlled it all - but at the end of the day, thats the landowners decision.

Some might argue that they control too much as it is!

[SPEEDTRIPLE]

18 minutes ago, marshman said:

It would make life a whole lot easier if the BA actually controlled it all - but at the end of the day, thats the landowners decision.

No disrespect MM, but it might make it easier for the BA, but it's possible that would be completely detrimental to a great many people, the boating community being only one group of them. 

[marshman]

Have I been misunderstood? Whilst I agree it would be easy to leave the detritus on the bank, its the decision of the landowner isn't it? Since when have landowners ever bothered about the boating community - they care less for them than the BA!

[Vaughan]

14 minutes ago, marshman said:

they care less for them than the BA!

And what's more, they profit greatly from mooring on their land.

[MauriceMynah]

This is rare!!

Marshman, I agree entirely.

Vaughan, I disagree entirely!!

SPEEDTRIPLE,, I don't entirely agree with you.    (Normality restored.)

[marshman]

Does that mean I am exonerated?????

[MauriceMynah]

Only if you do it in a darkened room well away from children.

[grendel]

exonerated - breaking it down into parts

ex - used to be - has been

one - singular

rated- having a standard or value assigned

so combining those - a singularly standardised has been 

[marshman]

'Bout sums it up really! 

[SPEEDTRIPLE]

9 hours ago, MauriceMynah said:

This is rare!!

Marshman, I agree entirely.

Vaughan, I disagree entirely!!

SPEEDTRIPLE,, I don't entirely agree with you.    (Normality restored.)

Now that's a perfect example of "hedging ones bets". Either that or the risk of a very sore ar5e through sitting on the fence. 

Hedges and fences, have I accidentally hijacked this thread into one about gardens?. 

[JennyMorgan]

9 hours ago, MauriceMynah said:

Only if you do it in a darkened room well away from children.

And take your cuff-links off so they don't rattle!