Swiss Federal Gymnastics Festival

[Roderick]

Some details here

And some video here

[david.elsbury]

I'm not sure of your intentions of posting these?

Do you have any views on them? I assume you must, if so, why not post your thoughts?

If you want discussion, surely this is the way to go about it, if not, why not ask the mods if we can have a "news" forum for these - to keep them seperate, or to post them all in the one topic?

 

Is there anyone on this forum that actually benefits from knowing? If I were a marquee company doing things "dodgy-illy" then the news of this wouldn't stop me...

 

Yes it's sad when people are injured, maimed, or killed, but... cowboys will still continue to be cowboys, especially when clients buy or contract based mainly on price...

 

2c

David

[Tomo]

While cowboys may continue to be cowboys, if nobody hired them they wouldn't get the opportunity to put people at risk.

 

If more potential clients know what could go wrong, perhaps they'll be less influenced by the headline price and be less likely to hire the bad companies?

 

</devilsadvocate>

[musht]

I'm not sure of your intentions of posting these?

 

 

Roderick is deeply involved in trying to make events safer, as his signature shows.

 

There has been a large number of safety related incidents involving outdoor structures in the last few years.

 

Quite a few people on the forum are involved in erecting marquees for a start , then there are many members who are either involved in the organisation of outdoor events or attend them as customers.

 

>Is there anyone on this forum that actually benefits from knowing?

 

See above.

 

> cowboys will still continue to be cowboys, especially when clients buy or contract based mainly on price

 

Didn`t see anything in the linked story or video to infer that any of the structures were of `cowboy` construction, sure that will be part of subsequent investigation.

 

Do note that the camping tents are of a uniform colour suggesting a central supplier and similar design.

 

Appears to be a severe weather incident outside of what could reasonably be protected against. Pukkelpop 2011 was another recent severe weather event:

 

 

The `benefits from knowing` are that even with people like Roderick working extremely hard at an international level , often with less than little thanks, to help keep people safe, safety is a personal responsiblity and there isn`t always a `cowboy` to blame.

[ImagineerTom]

There are some cowboys on this job - there's a load of "pop-up" tents branded (I assume for a sponsor) which are clearly the cheap far eastern copies and which have absolutely no place on a professional site; the proper pop-up tents are a flimsy compromise, the cheap copies are never acceptable for use as anything other than a sun-shade which should be taken down in anything over 10mph wind

Secondly someone didn't bother to watch the weather forecast - that site should have been closed and evacuated or at the very least suitable precautions taken.

Thirdly the banners on the truss structures haven't been fitted with break-away fixings (a huge no-no)

Forthly anyone who provides any marquee / bigtop without walls in place (and doesn't have them on standby and is watching the weather so that if it does turn they can get the walls on fast) has no business putting up or supplying tents. ALL the strength and structural integrity in wind/rain is based on them being fully assembled with walls on. Without walls the roof becomes effectively an aerofoil and the different pressures rip the structure apart (big-tops have special blow-out vents in the top of them to prevent this from happening which is one of the reasons why they have much higher wind ratings)- There's no doubt in my mind that that clearspan structure would definitely have lasted much longer (and could quite possibly have ridden out a short storm) if the walls and cross-bracings had been on.

[Roderick]

David,

My main reason for posting these things is to learn from them.

Incidents are bad but not learning from them is unforgivable.

 

I also prefer to post purely the facts at hand without any suggestions or finger pointing.

The finger pointing can be done by the local authorities, I really don't care about that side of things.

I care about comments like the Tom's who speaks with an in-depth knowledge of the subject.

Simple things like "why weren't there any walls on the structure" may just trigger a question next time you see a structure on your site without walls.

Tom also gave a clear explanation why the walls are required which will give you "ammunition" to question your supplier.

 

And that is where the value is.

[smalljoshua]

Would the place of authority in this be the MUTAMarq guide in the UK? I'd quite like to be able to qualify my comments on a structure in the future given recent events.

 

Josh

[ImagineerTom]

MUTA's paperwork and guides are very good but they are non the less "generic" guides offering guidance that's full of caveats; whilst they're interesting and useful starting points any tentmaster worth his salt should be able (and happy) to talk you through the calculations and assumptions he has made in THIS situation and be able to cross reference them to specific calculations (either from the manufacturer or a structural engineer) to show how in this situation the configuration chosen is appropriate and within parameters the structure is designed to operate within. If he's left equipment out he should be able (and happy) to explain why and show what process's he has in place - for example at the promoters request we often leave the sides off a Bigtop at a festival site (it encourages people to come in and enables a bigger crowd to see the performance) but we will always have those sides stored close to the tent, easily accessible & an appropriate number of staff on-site so that if a weather alert comes through we can get the sides put on quickly to dramatically improve the durability of the structure. I know the guys at Kayam & AJ bigtops have similar policies - I know of other bigtop/structure companies who don't event bring enough walling with them to site and will leave open tents completely un-attended. You can guess which companies we are happy to recommend to customers when we are too busy to take a job......

 

There's a broader problem within the marquee industry that in the last 10 years its changed from being a business that requires specialist skills to put up structures (carefully) designed by a handful of manufacturers to (literally) a free for all with no checks and balances. You could shell out £10k and buy a "new" clearspan marquee from an unknown Chinese manufacturer that will hold 1000+ people, have no training, no expertise and be putting it up at an event next week as sadly most event bookers choose entirely on price. Festival Republic (Latitude, Leeds, Reading, Glastonbury & many others) now employ structural engineers at each festival who do nothing but go around the marquees / structures that have been put up and calculate whether it actually is safe because they now generally cannot trust the companies supplying structures and their crews to actually be the highly trained precise operators they once could. Increasingly hire companies are choosing structures based not on their strength, durability or features but predominantly on how transportable they are and how few crew hours are needed to put them up with the net result that we are ending up with flimsier and flimsier structures and (as you can see in the swiss video) companies that would rather supply dozens of small structures (which are cheap to buy and quick/cheep to put up) pushed together to cover a large area but with basically no structural integrity than specify a larger, stronger single structure simply because the former can be put on a trailer behind a car and set-up by 2 unskilled staff whilst the latter requires a lorry and a team of experienced / skilled people.

 

Essentially the problem is the same as the DJ world - beginners with cheap kit wiping out the market for people who are actually good at their job - but when it comes to structure it's literally peoples health & lives you're gambling with and the cost of clearing up the mess runs in to millions.

 

//gets off soapbox//

[kerry davies]

Way to go Tom, not a soapbox but an informed and sensible post.

 

It is good to know that Josh knows about Mutamarq but it is not good enough. The Guide to Temporary Demountable Structures issued in 2007 by the Institute of Structural Engineers is what even Mutamarq refers to. If only for that Roderick's post is worth placing in the safety forum.

 

Besides that there are groups of interested professionals in Europe, North America and the Antipodes who are all together looking at every incident they can get hold of and the common factors are becoming understood. Freak weather is one and it is becoming less "freak" and more "normal". Cost-cutting and use of non-specialist equipment and people is another. Lack of emergency planning is another and in most of the cases a sensible safety officer would have called showstop and evacuated the site long before anyone was hurt or killed.

 

Just because a marquee is alleged to be able to withstand a 50mph wind doesn't mean it is fine to proceed in 49mph wind forecasts. Gale Force 9 (47-54mph) is weather for sitting in front of the fire not being out in a field. "Some branches break off trees, and some small trees blow over. Construction/temporary signs and barricades blow over." Gazebos and cheapo marquees fly around stabbing people.

At 80 mph (Hurricane Force) which this event saw, "Well-constructed houses and buildings should not suffer significant damage. Unanchored cottages and mobile homes are likely to be shifted off their foundations."

[Roderick]

Tom puts his finger exactly at the problem - cheap copies and the operators that own them.

 

If we are talking about a counterfeit copy of a wobbly bucket (moving light) than the worst that can happen is poor light output or visual abuse by inexperienced operators.

When it comes to structures, stage and ground support roofs it becomes a lot more serious.

And not primarily because of the way the structure was built but more importantly the inexperience of the operator.

That is where Kerry's post is so right, if you don't understand that 49kph is as dangerous as 50kph then you have no place in this area of the industry.

An inexperienced operator could cause a perfectly legit structure to collapse in the same way an experienced operator could use a Chinese copy safely.

 

How can we fix this problem, that is the crucial question. The fascination our society has with 'cheap' is starting to reach areas where is has a large potential to kill.

But how do we stop or at least control this insatiable want of 'now' and 'cheap'?

How do we go back to the Golden Triangle: Fast - Cheap - Safe (Good). Pick any two and it won't be the third?

[paulears]

I can't check because BT haven't fixed my internet, but in the video, was one of the big marquees actually a permanent structure? It looked like one was a proper heavy duty structure - and the sides blew in.

 

I'm a complete marquee moron - and every attempt at tents for me has been dreadful.

 

Whenever I go into a marquee I must admit to never giving it any attention, unless I see big heavy items attached to the roof in ways discussed over the years on the BR - or perhaps NOT in ways discussed.

 

The wind in those clips seemed to me to be the kind of level at which surely any structure wouldn't be able to cope with? The small tents just taking off makes me wonder if the 'genuine' products are designed to cope with that. I appreciate (and didn't know) there were imported products, but I guess I shouldn't be surprised.

 

When marquees were timber poles and canvas, were they any safer. Common sense says they would just have blown away. Modern marquees seem to be modular, so is the real problem the construction, or the ease that bigger structures can be built?

 

As a non-expert, the kind of weather there would seem to be sufficient that even the best lightweight structure would be destroyed. Is any marquee going to be safe in those kinds of winds? Surely a very long wall of flappy stuff can't survive? Can it?

[ImagineerTom]

In those sorts of winds you're right that most structures would be damaged however there's different degrees of damage and there's different levels of durability. That video shows.....

Various camping tents flying in the wind

Various "pop up" tents flying/skidding and just generally mangled (as above they're the cheap gazebo's)

Some truss structures (with banners on) bent and twisted

A Long clearspan structure (without walls on and missing half its cross bracing) being ripped apart

A Bigtop falling over when its main guys fail so that it can bellow which in turn pulls it apart.

 

As you know bigtops are my Forte - we generally use Canobbio bigtops because they are over-engineered to the max; everything is heavier, stronger & thicker than it needs to be and as a result they are calculated to withstand 90mph winds (we've certainly had one up in and surviving 80+mph wind, the Moscow state circus one survived 90mph winds on the Irish coast) but just like everything else in life there are other manufacturers and cheaper products. Miotti bigtops are made of lighter-weight materials and every one I've handled has a top wind rating of 50mph, there's smaller manufacturers and even Chinese makes I've seen that move worryingly at just 20mph.

 

You're right that "a long wall of flappy stuff" can't survive - but in the bigtop world we all switched to Tensile construction 20 years ago - if you ever see a bigtop that's got a flappy roof and/or has 20+ poles inside (so called queen poles, not the wall poles) holding up the roof you'd be best to walk away immediately as its either not been put up properly or is a very old tent. As I mentioned before there's an inherent design problem in clear span structures (as well as capri's and all these other "quirky" new mini marquees you can now get) that they are being designed with erection and transportation in mind, NOT quality, use or durability so are always going to be massively compromised in any unusual weather situation.

 

As mentioned above; your tentmaster & crew can make all the difference; 3 years ago on one festival site torrential downpours and wind hit, the ground was failing, water was pooling, it was a nightmare. All of our structures stayed up and remained open (as my crew were pro-actively adjusting and fixing issues as they started to occur) whilst other structure on site were collapsing, leaking and being evacuated because they weren't put up properly initially and weren't actively being managed during the storm.

[cfmonk]

The terrifying thing is that nobody from the festival closed that large tent down. Yes the guys who installed it have a responsibility and Tom's point about the walls is correct (although please don't think that you can never have a clearspan structure without walls, it just has a lower wind rating) but having an effective system in place for evacuation and closure of sites and temporary structures still seems to be something not enough people think about. I'm sure Tom, Roderick and Kerry all were doing the same and screaming in our heads "Get out, get out" when we saw people sheltering in a marquee from a storm of that power and the question is why wasn't somebody there shouting that? Same at Pukkelpop.

 

It's very easy for members of the public to assume without that temporary structures are the same as an actual building. Especially (although not in this case) now we can make them feel very much like that inside but it's not OK for organisers to think the same.

 

With regards to MUTA as has been said some of their advice is very good (although I have concerns about their apparent non-concern with events under 300 people in a lot of areas) but the real advantage is that by using a MUTA member (of which we are about to become one) you know that they are using proper equipment and have an acceptable track record and staff training regime.

[paulears]

Forgive another stupid question, but if I read it right, operating with the walls out is actually worse? I'm thinking that in my non-expert common sense only mind, I;d have perhaps been tempted to open up the sides to let the wide pass through? Is this an absolute no no?

[indyld]

Forgive another stupid question, but if I read it right, operating with the walls out is actually worse? I'm thinking that in my non-expert common sense only mind, I;d have perhaps been tempted to open up the sides to let the wide pass through? Is this an absolute no no?

 

One word: Aerofoil.

 

Also, I guess that perhaps certain designs could feasibly use the wall fabric for lateral stability between the bays (along with the various scissor or diagonal tension bracing etc.) but that's an assumption on my part. Be interested to know how much of the covering and walls in any given design is there to transfer tensile loads and how much just keeps the elements out. Suppose it depends on the design.

 

Edit to add to the one word: While it might seem prudent to "reduce sail", remember that a boat can sail faster than the wind speed due to differences in pressure either side of the sail as an areofoil (and the opposing foil below the water, keel etc.) This point of sail isn't straight downwind (I.e at wind speed) but across it. All this ignores what used to called hull speed, of course, which (sorta) limits the top speed of any design. But I digress. A sail is just an areoplane wing on its side and is relevant here.