Here’s a newly installed floor plate for a set of women’s bars. A standard installation.
That’s a single point of failure. If something goes wrong, the bars fall. As they did on Ludmilla Tourischeva in 1975.
Almost every coach has seen this happen. It’s not all that rare.
Why don’t we double floor plate gymnastics apparatus?
Kelly Manjak and I did that at Altadore in 2004, but I’ve never heard of any other instance.
Leave a comment if you know of a gym that has doubled floor plates. Or of equipment installed such that one chain failure won’t allow the apparatus to fall.
10 comments ↓
Did lots of research into this last year. You raise a good point. We have mostly chemical anchors in our gym, but yes, all single points. By all accounts, with a chemical anchor, the concrete is likely to fail before the anchor bond would, so double anchoring too close together when using a chemical socket might weaken the concrete, so would have to consider how far apart they are.
I don’t have as much faith in the classic drop in floor anchors.
I’m not an engineer, so can’t speak about the science… but here’s a technical doc: http://www.chemical-anchoring.com/docs/Chemical_Anchor_Technical_Handbook_072008.pdf
Thanks Tim. I’m completely unaware of the Chemical Anchors. We’ve only used drop-in anchors, and did indeed weaken the concrete by putting two anchor holes too close to one another, in the past.
Rick, myself and my friend Ian upgraded the floorplates at Phoenix last year to a system that has a floor plate that is a flat base with 3 to 4 corner bolt holes that then bolt through to the floor via anchors or wedge bolts (thanks for the tip Jim) and have a 1/4″ steel plate welded onto it for the attachment. Having that many bolts makes catastrophic failure of the plate virtually non existent.
At the same time we also used the same anchor system to replace all high wire/trapeze/high ropes attachments for the local circus people operating from that facility although they kept assuring us that a single eyebolt and anchor was perfectly safe for all of the skills that they were performing over 25′ in the air over minimal mat surfaces. You think a collapsing high bar is dangerous..
Not only the anchor is to watch, according to me, the whole part from the floor to the bar should be checked.
I had an issue with that one day : a member of the club’s committee decided on his own to change the original damaged carabiner (I think that’s the word in English) by another one he bought in a DIY shop.
But it was not designed to handle such a tension, and it broke while a gymnast was on it. No injuries, but a big fright for everybody !
Since then, I regularly check everything from the bottom to the top of the cables.
Good tip. Thanks.
Wow.
Awesome George.
Email a photo when you get the chance.
“But it was not designed to handle such a tension,…”
Looks like that was the main problem. If he had bought a carabiner at the DIY shop that was designed to handle the right load, there most likely never would’ve been a problem. At least not until it wore out after awhile.
Rather than double floor plates, how about the equipment manufacturers provide floor plates which accept two bolts maybe 100mm apart? Any such part available?
Yes. The standard installation on a wood floor is 4 screws.
But in concrete the fear is that two holes so close together weakens the concrete. … I’m no expert, of course.
[...] is a follow up to the post on single point of failure industry standard apparatus cable floor [...]
Leave a Comment