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2 hours ago, Steve Pope said:

In the photo of the damaged strut it showed that all the bolts on that particular plate had sheared, I would be very surprised if other bolt ups are not partially sheared as well. Not going to be a quick fix.

Apparently they are design to fail, so that the rest of the structure is not damaged. But yeah, give something a big knock, chances of some damage elsewhere are not insignificant.

Don't forget a possible outcome here is the bridge actually falling down. That would be a bit more than a few weeks inconvience ...

Bridges do fall down fairly regularly. There was that key motorway bridge in Italy that came down, with cars and trucks on it, killing people. First world, developed country and all...

 

The Morandi bridge tragedy killed 43 and left 600 homeless – but also dealt a hammer blow to Italy’s engineering legacy

https://www.theguardian.com/cities/2019/feb/26/what-caused-the-genoa-morandi-bridge-collapse-and-the-end-of-an-italian-national-myth

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What complicates the matter is that strut is a stressed member. Fabricating a bit of steel is the easy bit, getting it in there is somewhat harder Imagine trying to replace a spreader, and you ha

Jeez why ask them when they could just get you guys to do the job.  Personally I would prefer the job to be done properly rather than the quickest patch up fix with Cheapest Chinese Steel and Cut Corn

before the gvt and council bashing gets started how about moving this to tiny talk

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When the Clip-on's under went their repair. Happened to meet the Swedish engineer at Robertson park mangere.(steam trains)He reckon the repairs would only last another 10/15 yrs,that was 2009 and the main span was made from inferior metal.his recommendation was not to think about a new crossing but rather to start.

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What complicates the matter is that strut is a stressed member. Fabricating a bit of steel is the easy bit, getting it in there is somewhat harder

Imagine trying to replace a spreader, and you have to get the rig tension and mast bend back to where is should (must) be, without touching the turnbuckles or addind any significant weight aloft.

Its certinaly not beyond the wit of man to complete, but considering the implications if it goes wrong the amount of planning, peer review  and analysis that goes into this will be significant

 

 

 

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9 hours ago, Romany said:

I'm not sure what the problem is there Dtwo.  I don't believe that anything in my reply indicated a sh*t job was acceptable, just that it seemed the engineering was already available and has been proven by father time.

This.  Not so much your comment but a stream of bollocks from others.  Yawn.

'Yep, too much navel contemplating, and cuzzy consulting.

Get it done, son.

I'd think that one of the pollie parties would sieze on this as an election issue.

Yes days on it would be good to think that the meetings and discussions have finished and that the fabrication to engineers drawings has commenced -it would have elsewhere in the world. Who do we ask that straight question to ?'

 

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I would be rude not to acknowledge that NZTA does seem to have pulled a rabbit out of the hat. Temp repairs underway tonight is a pretty good response.

Who woulda thought that a 61 year old bridge was as technilogical as it sounds eh. I just thought it was a giant meccanno set

 

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Just to preface this, I'm not a bridge, mechanical or structural engineer, so this is all best guess from heavily loaded snafus I've seen over the last 20 yrs

 

IT, you're right Its a reasonably long slender member, so it will have a bit of stretch one loaded. However,  I would guess though that the bridge structure itself has moved more that that. If Vic remade the piece to the original dimensions, when you went to install it you would probablly find it would appear to be to short ad the structure will mave likely moved away. The challenge is then to pull the structure back to the correct shape while still leaving space to install the new part and not overload anything else in the process

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1 hour ago, Ed said:

Just to preface this, I'm not a bridge, mechanical or structural engineer, so this is all best guess from heavily loaded snafus I've seen over the last 20 yrs

 

IT, you're right Its a reasonably long slender member, so it will have a bit of stretch one loaded. However,  I would guess though that the bridge structure itself has moved more that that. If Vic remade the piece to the original dimensions, when you went to install it you would probablly find it would appear to be to short ad the structure will mave likely moved away. The challenge is then to pull the structure back to the correct shape while still leaving space to install the new part and not overload anything else in the process

from what I can make out this strut is in compression as part of the support truss so if this is the case stretch/elasticity would not be an issue

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