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cooling tower project


Original Post
Frank Niehus · · Unknown Hometown · Joined Dec 2018 · Points: 0

Hello,

I'm new to this forum and not sure if this entry is right here. However, I think that your experience in the area of rope attachment could be very helpful for an upcoming project, which will be taking place in a disused cooling tower(89 m diameter). In the broadest sense, the planned installation is similar to a slackline / highline setup.

First of all a few basic info about the structure:
The intended use involves the use of the inner cooling tower concrete cladding (concrete grade not known, probably > B35) for the purpose of restraining an approximately 2m installed at 3 suspension points in 17 meters height through three slackline-bungee cord-icosahedron joints. The icosahedron construction will be located in about 5 m height in the cooling tower center.

For the basic clarification of the structure, I have attached a picture.

The first purpose of the setup is to climb inside the icosahedron structure and create a vertical bouncing of the system in the amount of several meters by body centering displacements. You could use a harness in combination with a slackline leash and climb or maybe walk on the line to reach the icosahedron structure from one of the three suspension points. Because of the cooling tower structure, it is difficult to reach the suspension point, therefore a slackline leash makes no sense. So for the cooling tower I will use a rope ladder to climb inside. For the next year I plan to install the structure in a cliffy environment, thus a slackline leash could become very effective.

My actual question relates to the planned attachment to the cooling tower concrete wall and whether it is reasonable or stable enough.

The icosahedron construction (40kg empty weight) weighs about 150 kg with me and additional equipment and should form an angle of about 15 degrees to the suspension points. The tensile forces
should be more or less 2 KN for each of the 3 suspension points. As a result of the dynamics generated, the tensile forces could increase up to 4 KN.

In the upper area (17 m height), four Fischer FAZ II M12 / 30 anchor bolts should be placed at each of the three suspension points (the boreholes are approx 25 cm apart) in combination with bolt tabs and M8 quick links connections. Due to the four quick links connections, a 10.5 mm static rope should be guided through two M12 delta quick links (50KN) and be freely movable. Each strand is then about 80 cm long. As a connection node a triple or fourfold fishermens knot is considered. In addition, each rope strand is to be secured by means of a 16 mm sling loop via a figure 8 follow through knot as a back up system. Maybe I could use one long tape and bring all tape strands to a central point and tie a big figure of 9 on the bight(loop) as a backup system, because it will have more regular strands.By the two delta quicklinks two slacklines (the second slackline serves as a backup) are deflected, starting from the icosahedronto a steel plate near the ground (25 cm x 30 cm x 0.8 cm, fixed with 4 Fischer FAZ II 12/30 anchor bolt on the Cooling tower wall) by means of two Gibbon shackles (50 KN). As Weblocker I will be using lashing buckles (breaking load 50 KN). Because of the slackline deflection, the upper fixed points in 17 m height are more loaded. The advantage however results from the better handling during clamping. An assessment would be very helpful.

many Greetings

Frank

Drew Nevius · · Oklahoma · Joined Jun 2012 · Points: 1,884

I hope the attachment points on the icosahedron cage are really strong, as failure of one of those 3 mount points would result in a ground fall.

Depending on what material is used between the 3 attachment points on the cage out to the walls (which will be ~40m away), those anchors may need to be higher than 17m up to keep it off the ground. Or a tensioned static line/webbing will be needed. 40m is a long way

curt86iroc · · Lakewood, CO · Joined Dec 2014 · Points: 69

Dude, go see an engineer. 

Mike G · · Pennsyltucky · Joined Oct 2017 · Points: 0

While each individual anchor is bomber and the manner in which your anchors are set up is well understood and known to be safe, the more unique component in the system is the icosahedron cage. I would be interested in the kind of load its experiencing, not just at the attachment points but the cage itself, as at the circumference made by the three attachment points the cage isn't a perfect ring and I have no idea how the cage distributes those three axis of pull, just my thoughts, its a rather unique thing to suspend in this manner and I'm willing to bet itll be fine with your expected forces. but as Drew said IF a leg does blow the cage is looking at taking a huge swing either into the tower wall or the floor. I'm not sure that mountain project is the best place to search for approval of this project though you likely will get some great minds with experience replying.

Jim Titt · · Germany · Joined Nov 2009 · Points: 490
curt86iroc wrote: Dude, go see an engineer. 

Well yeah. This has already been posted on UKC  day ago and the important stuff has been left out, what is the liability? For private use the OP can do what they want and use any advice from the internet they want, whether it´s right or not we don´t give a shit. If it´s not private then it´s pay for a structural engineer to calculate everything, spec it and sign the whole thing off.

curt86iroc · · Lakewood, CO · Joined Dec 2014 · Points: 69
Jim Titt wrote:

Well yeah. This has already been posted on UKC  day ago and the important stuff has been left out, what is the liability? For private use the OP can do what they want and use any advice from the internet they want, whether it´s right or not we don´t give a shit. If it´s not private then it´s pay for a structural engineer to calculate everything, spec it and sign the whole thing off.

i totally get it, but it doesn't change the fact that the OP obviously has very little knowledge and i'm not sure a recreational climbing forum will provide the best advice. 

Sam Skovgaard · · Tucson, AZ · Joined Oct 2017 · Points: 87

Skip the slack line, turn that thing into the coolest artificial climbing wall in the world!  Looks like it's tall enough for multi pitch.

Frank Niehus · · Unknown Hometown · Joined Dec 2018 · Points: 0
curt86iroc wrote: Dude, go see an engineer. 

This project is only a temporary installation and not a permanent one, so the mobility aspect with the rope system is important for my purpose. To filter out all the information I have given in my first post, I need some information about a flexible and reliable rope attachment for the wall. A normal structural engineer could probably not give me information about good climbing knots or quick links. Seeking an enginer would be the right decision to examine the croncrete of the cooling tower so that the anchor bolts will fit. 

Corey Day · · Philadelphia · Joined Jul 2016 · Points: 5
Frank Niehus wrote:

... Seeking an enginer would be the right decision to examine the croncrete of the cooling tower so that the anchor bolts will fit. 

Depends on the experience of the firm you approach. I recommend seeking out a rigging engineer or professional with with rigging or rope access experience, they deal with suspended loads and temporary anchors all the time. Please get professional's help so you don't get anyone hurt. 

alpinejason · · Minneapolis · Joined Apr 2010 · Points: 176
Where is this located? We definitely have a staff of engineers that could provide professional services to make sure this is done well. 
Frank Niehus · · Unknown Hometown · Joined Dec 2018 · Points: 0

Thanks for your reply, the project is located in northern germany. 

Tradiban · · Unknown Hometown · Joined Apr 2004 · Points: 11,510

4 bolts that close don't distrabute the load effectively on the tower.

Jim Titt · · Germany · Joined Nov 2009 · Points: 490
Tradiban wrote: 4 bolts that close don't distrabute the load effectively on the tower.

The minimum distance for that bolt is 50mm and the maximum 210mm and since the OP has said they will be 250mm apart I guess that´s covered.......after the rotting concrete has been tested.....

As for the rest of it:-
The cooling tower is in the Fun Park Meppen (a large motorsports orientated activity park) and thus subject to German law. If the installation is for artistic purposes (circus or similar) it falls under one set of regulations, the standard number I can´t remember but it´s easy enough to look up. Otherwise it´s fun-fair stuff and comes under DIN EN13814 for "flying rides". There is no exemption for private use. For both the standards none of the proposed equipment would pass any of the requirements, knotted tape isn´t really the thing and nor are slackliners quicklinks, line lockers and the rest.
I do a few of these occasionally, the last one was the anchoring points in a sandstone church for the ariel "flying angels" in a Nativity play in Dusseldorf and for individual anchor points it´s tested steel strops to a central ring and equalised with turnbuckles, if possible you just go to a welded steel attatchment plate (in the church we couldn´t).
The cage thingy the TÜV guy is just going to laugh, to work out the required strength would be okay but since it´s made of 8mm thread-all and bamboo it´s going to be fun seeing the calculations, normally it would be welded 2mm wall stainless tube. As the holes in it are quite large you´d also need a certified attatchment point for the safety leash or a safety net below if it´s for artistic use.
Since the fun park is a large commercial operation (off-road experience stuff, full-on car racetrack etc) I´m sure the manager and his insurance guy will take care of it all anyway!
Tradiban · · Unknown Hometown · Joined Apr 2004 · Points: 11,510
Jim Titt wrote:

The minimum distance for that bolt is 50mm and the maximum 210mm and since the OP has said they will be 250mm apart I guess that´s covered.......after the rotting concrete has been tested.....


To close in the sense that they wouldn't cover multiple rebar spreads.
Jim Titt · · Germany · Joined Nov 2009 · Points: 490
Tradiban wrote:
To close in the sense that they wouldn't cover multiple rebar spreads.

I bow to your superior knowledge! What exactly was the rebar pattern and embedment used in a cooling tower in Germany thirty years ago?

Tradiban · · Unknown Hometown · Joined Apr 2004 · Points: 11,510
Jim Titt wrote:

I bow to your superior knowledge! What exactly was the rebar pattern and embedment used in a cooling tower in Germany thirty years ago?

Hell if I know, dude needs an engineer or at least the specs.

If I'm visualizing his set up correctly wouldn't he want to spread out the four anchors as independent evenly accross the tower?
t.farrell · · New York, NY · Joined Aug 2016 · Points: 60

Do you have hi res photo of 3rd image posted? I quite like it. 

curt86iroc · · Lakewood, CO · Joined Dec 2014 · Points: 69
Jim Titt wrote:

The minimum distance for that bolt is 50mm and the maximum 210mm and since the OP has said they will be 250mm apart I guess that´s covered.......after the rotting concrete has been tested.....

As for the rest of it:-
The cooling tower is in the Fun Park Meppen (a large motorsports orientated activity park) and thus subject to German law. If the installation is for artistic purposes (circus or similar) it falls under one set of regulations, the standard number I can´t remember but it´s easy enough to look up. Otherwise it´s fun-fair stuff and comes under DIN EN13814 for "flying rides". There is no exemption for private use. For both the standards none of the proposed equipment would pass any of the requirements, knotted tape isn´t really the thing and nor are slackliners quicklinks, line lockers and the rest.
I do a few of these occasionally, the last one was the anchoring points in a sandstone church for the ariel "flying angels" in a Nativity play in Dusseldorf and for individual anchor points it´s tested steel strops to a central ring and equalised with turnbuckles, if possible you just go to a welded steel attatchment plate (in the church we couldn´t).
The cage thingy the TÜV guy is just going to laugh, to work out the required strength would be okay but since it´s made of 8mm thread-all and bamboo it´s going to be fun seeing the calculations, normally it would be welded 2mm wall stainless tube. As the holes in it are quite large you´d also need a certified attatchment point for the safety leash or a safety net below if it´s for artistic use.
Since the fun park is a large commercial operation (off-road experience stuff, full-on car racetrack etc) I´m sure the manager and his insurance guy will take care of it all anyway!

hmmm sounds quite like the kind of analysis done by...an engineer....

Jim Titt · · Germany · Joined Nov 2009 · Points: 490
Tradiban wrote:

Hell if I know, dude needs an engineer or at least the specs.

If I'm visualizing his set up correctly wouldn't he want to spread out the four anchors as independent evenly accross the tower?

I'd just fit a bolt right through with a backing plate anyway but I guess access both sides at the same time is going to be expensive.

Tradiban · · Unknown Hometown · Joined Apr 2004 · Points: 11,510
Jim Titt wrote:

I'd just fit a bolt right through with a backing plate anyway but I guess access both sides at the same time is going to be expensive.

Im guessing a cooling tower woukd be pretty thick and would require one helluva drill bit.

Jim Titt · · Germany · Joined Nov 2009 · Points: 490
Tradiban wrote:

Im guessing a cooling tower woukd be pretty thick and would require one helluva drill bit.

They are kinda thin! The ones which blew down in the UK (1965 Ferrybridge) were of similar size and design to the one we are discussing (115m high and 88m dia base and they were 127mm/5" thick and that´s pretty normal (the remaining ones were upgraded to 7").

Guideline #1: Don't be a jerk.

Fixed Hardware: Bolts & Anchors
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