Etihad Campus, Stadium and Collar Site Development Thread

[Ardwick Green Blue]

I understand what you are saying, but the access tunnel cannot be blocked at any time for the expansion, health and safety will never allow for the tunnel to be closed

This was possibly covered a few posts ago. I was working on the assumption that the build would be the same as the South Stand...some preparatory work commencing before the end of the season and then two close seasons and one full season to complete. In this case 10 concerts isnt a possibility. However it seems like it will be a two year build.

 

[HelloCity]

If the South Stand roof doesn't use the cablenet then can you explain how the roof is supported? Genuine question

The cable is pre-tensioned the primary component of the structure that's why it was there during the games even without the north stand?

To quote from the CoMS Design study

A central feature of The City of Manchester Stadium is its distinctive and dynamic form, key to which is the structural solution for supporting the roof. The roof structure essentially comprises two separate structural systems, the first providing primary structural support to the whole roof (the ‘cable-net’), and the secondary being a more conventional arrangement of rafters propped from the rear of the concrete bowl and hung towards their leading edges from the cable-net. The mast and cable-net roof primary structure uses a ‘grounded tension ring’ to create a prestress field against uplift wind loads. 12 cigar-shaped tubular steel masts up to 65m high support a total of 76 spiral strand forestay cables in fanshaped groups of five or seven cables per mast. Each forestay supports an individual rafter. Just above the roof surface, all the forestay ends are connected by a system of four spiral strand cables that form the ‘grounded tension ring’ (also referred to as the ‘catenary’). Prestress to the catenary and cable-net is provided by four corner-ties anchored to the ground. The top of each column is tied back to the ground by pairs of back-stays comprising groups of Macalloy high tensile steel rods. This mast and cable-net system not only provides a highly efficient structure but also is central to the drama of the building’s architecture.

Yes. The new roof is supported independently by the two new giant triangular roof supports.

The old roof was supported as per the article piece you posted.

You can see the new supports in this picture below.

 

[Sheikh Rattle n Roll]

This was possibly covered a few posts ago. I was working on the assumption that the build would be the same as the South Stand...some preparatory work commencing before the end of the season and then two close seasons and one full season to complete. In this case 10 concerts isnt a possibility. However it seems like it will be a two year build.

Apologies, just caught up with all the comments

 

[Gordyola]

Yes. The new roof is supported independently by the two new giant triangular roof supports.

The old roof was supported as per the article piece you posted.

You can see the new supports in this picture below.

Yes, but that is part of the cable net system not specifically the ring but still part of it

Here's an article that you might like to read https://www.steelconstruction.org/design-awards/2016/award/south-stand-expansion-etihad-stadium/

Key quotes
The design was technically complex as the existing roof involved a cable net structure with a tension ring, from which steel roof rafters hung. The structural integrity of the existing tension ring relies on it running around the whole circumference of the roof; therefore any modification to the roof could not affect this, even in areas where roof rafters were removed. Protection of the existing cable was vital as there was no repair procedure in place, and damage would result in replacement and potentially the closure of the stadium for two years

The client also received a masterplan design which enables the stadium capacity to be expanded further to the absolute limit of the existing cable net, and then only at that point does the roof need to be completely replaced.

 

[HelloCity]

Yes, but that is part of the cable net system not specifically the ring but still part of it

Here's an article that you might like to read https://www.steelconstruction.org/design-awards/2016/award/south-stand-expansion-etihad-stadium/

Key quotes
The design was technically complex as the existing roof involved a cable net structure with a tension ring, from which steel roof rafters hung. The structural integrity of the existing tension ring relies on it running around the whole circumference of the roof; therefore any modification to the roof could not affect this, even in areas where roof rafters were removed. Protection of the existing cable was vital as there was no repair procedure in place, and damage would result in replacement and potentially the closure of the stadium for two years

The client also received a masterplan design which enables the stadium capacity to be expanded further to the absolute limit of the existing cable net, and then only at that point does the roof need to be completely replaced.

That is saying that the old cable net needed to be kept in place (and not damaged) due to it still supporting the other parts of the roof. It's still part of that support ring.

The new South Stand is built around the restrictions of the net, although it's new roof now has it's own independent support system.

 

[blueparrot]

Yes, but that is part of the cable net system not specifically the ring but still part of it

Here's an article that you might like to read https://www.steelconstruction.org/design-awards/2016/award/south-stand-expansion-etihad-stadium/

Key quotes
The design was technically complex as the existing roof involved a cable net structure with a tension ring, from which steel roof rafters hung. The structural integrity of the existing tension ring relies on it running around the whole circumference of the roof; therefore any modification to the roof could not affect this, even in areas where roof rafters were removed. Protection of the existing cable was vital as there was no repair procedure in place, and damage would result in replacement and potentially the closure of the stadium for two years

The client also received a masterplan design which enables the stadium capacity to be expanded further to the absolute limit of the existing cable net, and then only at that point does the roof need to be completely replaced.

As I understand it, while there is one part of the old roof using the cable net in place the whole cable net has to remain. But the new roofs don't actually use the cable net and when all the roofs have been replaced the cable net can also be removed. That's how I have understood posts from far better qualified posters than myself though, so I might have the wrong end of the stick.

 

[Gordyola]

That is saying that the old cable net needed to be kept in place (and not damaged) due to it still supporting the other parts of the roof. It's still part of that support ring.

The new South Stand is built around the restrictions of the net, although it's new roof now has it's own independent support system.

Yes but, it’s still part of a complete system that you suggested could be broken when clearly this is not possible without replacing the east and west roofs

 

[Gordyola]

As I understand it, while there is one part of the old roof using the cable net in place the whole cable net has to remain. But the new roofs don't actually use the cable net and when all the roofs have been replaced the cable net can also be removed. That's how I have understood posts from far better qualified posters than myself though, so I might have the wrong end of the stick.

Correct but it would be a major task to replace the east and west roofs

 

[HelloCity]

Yes but, it’s still part of a complete system that you suggested could be broken when clearly this is not possible without replacing the east and west roofs

We’ve been talking about the South Stand roof and how that is supported.

I only speculated about the cable ring being broken once the old North Stand is removed on the basis the sides may only need to be supported by the spiral masts. It’s unlikely but I discussed the possibility due to the muted 63k capacity goal.

Just to confirm, the South Stand roof is supported by the new giant triangular supports and does not use the old cable net in any way. The old cable net is kept in place to keep the cable ring in place.

The South Stand is specifically designed so that it doesn’t touch the old cable net at any point. It comes in through the gap between stand and roof, as well as through the corners.

This restriction meant the stand couldn’t be any smaller or taller than it currently is as the cable net wouldn’t have been able to feed through the back of the stand.

 

[Gordyola]

We’ve been talking about the South Stand roof and how that is supported.

I only speculated about the cable ring being broken once the old North Stand is removed on the basis the sides may only need to be supported by the spiral masts. It’s unlikely but I discussed the possibility due to the muted 63k capacity goal.

Just to confirm, the South Stand roof is supported by the new giant triangular supports and does not use the old cable net in any way. The old cable net is kept in place to keep the cable ring in place.

The South Stand is specifically designed so that it doesn’t touch the old cable net at any point. It comes in through the gap between stand and roof, as well as through the corners.

This restriction meant the stand couldn’t be any smaller or taller than it currently is as the cable net wouldn’t have been able to feed through the back of the stand.

You suggested that the cablenet could be removed when the north stand is developed, removing the restrictions caused by the cable ring being in place! With the east and west stands being supported by the current structure, spiral masts, without the cable ring, even though the cable ring is primary structure. I asked how the south stand roof is supported without the cable net you explained the tubular structures bolted to the steel verticals, fair enough, but the cablenet system, if not the pre-tensioned ring, is still in use (the cable ring passes through the structure)
So ultimate it’s highly unlikely that the cable ring, cablenet, can be removed unless new roof structures are installed for the east and west stands

 

[HelloCity]

You suggested that the cablenet could be removed when the north stand is developed to remove the restrictions caused by the cable net being in place! With the east and west stands being supported by the current structure, spiral masts, without the cable net even though the cable ring is primary structure. I asked how the south stand roof is supported without the cable net you explained the tubular structures bolted to the steel verticals, fair enough but the cablenet system, if not the prestensioned ring, is still in use the ring passes through the structure.
So ultimate it’s highly unlikely that the cable ring, cablenet, can be removed unless new roof structures are installed for the east and west stands

Jesus Christ mate.

I speculated it on the basis that the current cable ring restrictions wouldn’t allow us to reach the rumoured 63k through an extended North Stand 2nd tier. I too believe that wouldn’t be likely but I made the point based on that capacity goal and people at the meeting being told the cable net wouldn’t be an issue with development.

I then corrected you on the new South Stand roof on if it uses the old ring support or not. It doesn’t.

 

[Churchlawtonblue]

Chill guys, no point in falling out over a roof!

 

[worsleyweb]

I used to go for a pint every week with the man who was the only person to understand how that roof worked and did all the calculations a real character and an absolute genius. Will be long dead now I would imagine or I would ask him.

 

[Gordyola]

Chill guys, no point in falling out over a roof!

Not falling out Just a discussion, interesting to get to understand the possibility/ issues of the development

 

[Jacko1956]

Jesus Christ mate.

I speculated it on the basis that the current cable ring restrictions wouldn’t allow us to reach the rumoured 63k through an extended North Stand 2nd tier. I too believe that wouldn’t be likely but I made the point based on that capacity goal and people at the meeting being told the cable net wouldn’t be an issue with development.

I then corrected you on the new South Stand roof on if it uses the old ring support or not. It doesn’t.

Don't think that the cable net will change rather that the fact there wont be a cooperate area as there is between the second and third tier in the south stand will mean that a new complete tier that would include the current second tier would easily hold a further 8k as this would have further rows that couldn't be added to the south stand due to the layout.

 

[blueparrot]

Don't think that the cable net will change rather that the fact there wont be a cooperate area as there is between the second and third tier in the south stand will mean that a new complete tier that would include the current second tier would easily hold a further 8k as this would have further rows that couldn't be added to the south stand due to the layout.

That makes sense.

 

[HelloCity]

Don't think that the cable net will change rather that the fact there wont be a cooperate area as there is between the second and third tier in the south stand will mean that a new complete tier that would include the current second tier would easily hold a further 8k as this would have further rows that couldn't be added to the south stand due to the layout.

I’m not so sure looking at this.

Comparison of a 3rd tier vs an expanded 2nd tier.

I do think the new section would be steeper than shown here but that would still give less rows than a 3rd tier would allow with its overhang.

 

[Kinkys Left Foot]

Its an interesting conundrum regarding the cable net.
Obviously in its original design it formed part of the required support system for all 4 roof elements.
It has had the stresses significantly reduced by the removal of all the weight from the South stand roof.
If we build something similar at the North Stand end (with a similar self supporting triangular pillar set up) the weight stress will be further reduced.
Would it not then depend entirely if the current existing weight supports from the spirals of East & West stands could support the stresses of the individual stands without the cable net.
If not then either the cable net has to remain in its current form or the cables supporting East & West or have to be altered so that the exiting cable elements of East & West are anchored in an alternative fashion. Alternatively I could imagine additional self supporting triangular pillar set ups being incorporated onto East & West stands (this might be preferred at this point as I think any further development of either East & West would require additional support) enabling removal of the cable net altogether.
We'll have to wait and see when the plans are drawn up and released.

 

[Manchester_lalala]

I’m all up for a big tier, but the stadium is going to be a bit of an off shape. Would look incredible if the Colin bell and east stand joint up to the south.

 

[UUJblue]

I’m all up for a big tier, but the stadium is going to be a bit of an off shape. Would look incredible if the Colin bell and east stand joint up to the south.

Always bugged me that, just where the big screens are now to fill in the corners. I not sure if possible but even if we add 10 or so rows it would add a few thousand with both corners?