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Ramp Failure Video In Europe

Posted: Thu Jan 04, 2007 6:07 pm
by Wesley Tucker
I hate doing this, but it's the only way I know to ask.

Can anyone direct me to that video clip of the racer WHO FELL THROUGH THE PLYWOOD RAMP? i remember the plywood gave way and a hole about the size of his skateboard swallowed the board and fell almost flat on his face.

Thanks for the help!

Posted: Thu Jan 04, 2007 7:11 pm
by Patrick Allan
There ya go...

viewtopic.php?t=4327

Posted: Thu Jan 04, 2007 7:58 pm
by Wesley Tucker
Thanks Patrick. That's exactly what I was looking for.

It's the best way to illustrate that a start ramp should have intermediate LATITUDINAL support as opposed to just ribs running the length of the S-curve.

Big open spaces of plywood are not necessarily the best way to support a skateboarder, especially when all the weight is then concentraed into just four wheel patches. Failure is almost inevitable.

Posted: Thu Jan 04, 2007 8:59 pm
by Steve Collins
That was some absurdly thin wood on that ramp.

Posted: Thu Jan 04, 2007 10:11 pm
by Erik Basil
It looks like it was wall paneling! 1/8, no ply?? Crazy.

Posted: Thu Jan 04, 2007 11:53 pm
by Stephen Lavin
That fall did not look good. Skater lost his helmet with side impact looks like. Was the skater Okay? Minimal damage I hope. I stopped the video after the second slow-mo.
SL

Posted: Fri Jan 05, 2007 1:35 am
by Jean-Sébastien Dennebouy
The skater on the video is the swiss rider Fabrice André, it was really shocked after the fall, which was a violent one ! He got a little finger fracture and some marks on his face...

Posted: Fri Jan 05, 2007 9:27 am
by Jani Soderhall
I was told the plywood was about 5 mm thick. Can't remember if there was one sheet or two. (I wasn't there)

Using thin plywood is very dangerous, even if there is support underneath. In my experience 10 mm should be thinnest plywood used. However the thicker it gets the harder it is to shape to the S-curve. If it get's too hard, just flatten out the S-shape!

I think the guys are planning a double or even triple sheets for next year, but personally I would prefer one single, but thicker sheet.

The exact same thing happened to me back in 1980, but luckily I managed to run it out.

/Jani

Posted: Fri Jan 05, 2007 1:45 pm
by Patrick Allan
The organisers had jut finished making both ramps the morning of the competition. They had planned on doubling the sheets but ran out of time so there was only one sheet of plywood (5 or 6 mm).
If you were heavy enough they would go "crack" when you went down :) ... amusing until the ramp broke... :(

Posted: Fri Jan 05, 2007 2:50 pm
by Wesley Tucker
Well, I'm not an engineer, but I think the Lyon ramp shows that any long unsupported sections of a ramp will lead to failure.

Even if 1/4" plywood were used (easiest to bend and secure around a curve) repeated riding will lead to areas of fatigue. Without cross supports eliminating the bowing and flexing of the wood, the possibility of failure is magnified. Riding over the top transition induces little stress. Riding down with acceleration to the second curve, though, has all the weight of the rider and board "impacting" the surface before transitioning off to the street.That's where the Lyon ramp failed and where any future ramps of similar design will have issues.

Sticking with Ricky Byrd's plan (a ladder-style of supports the length of the ramp) is better supported and less susceptible to cracking and failure. Like I said, I'm not an engineer, but it's pretty much common sense.

By the way, I'm just going by what's in the video. That hole covers an area that is twice as long as any section between supports on a Ricky Byrd ramp. Maybe there are cross supports elsewhere on the ramp, but that section isn't. All it takes is one weak area to ruin your whole day.

Posted: Fri Jan 05, 2007 6:06 pm
by Eddy Martinez
Got to agree on this one I have 2 Ricky Byrd ramps in my garage, both have plywood and then are covered with a layer of skate lite. They are heavy but very durable. I understand why the Euro ramps are so tall, and a racer has to get speed very fast. Makes sense. Your Amigo Eddy Texas Outlaws.

Don't run up the ramp either.

Posted: Fri Jan 05, 2007 6:43 pm
by Pat Chewning
It should be clear to racers NOT to run up the ramp to reach the top, but they still do it. The ramps at La Costa had to be resurfaced during the race because of this.

The impact of feet on the ramp while running up it is much greater than rolling down the ramp on a skateboard.

Posted: Fri Jan 05, 2007 7:41 pm
by fabrice andré
I love this video :)

Ok... I was the one who crashed... but ALL the riders present at this contest went down the ramp all day long without asking themselves (too much) questions !!!

After my crash, I think it's crazy :
- that organizers made such a ramp
- AND that riders accepted riding these ramps.

Posted: Fri Jan 05, 2007 8:37 pm
by Donald Campbell
regarding pat chewnings statement:
it should be clear that any ramp should be able to take a whole day's beating,which means going down the ramp or running/skating up the ramp.
if any ramp used at any race can not match that certain criteria IT SHOULD DEFINITELY NOT BE ALLOWED for any kind of race.

these are my words and you should put that statement into consideration to your previous post,pat.

Paper?

Posted: Sat Jan 06, 2007 1:41 pm
by Marty Schaub
I have used posterboard for my kids school projects that was thicker than that.

OH BTW

Posted: Sat Jan 06, 2007 1:49 pm
by Marty Schaub
Oh by the way,

In Tigers defense, he had ramps squared away but was told very close to the race that he would have to drive umpteen hundred miles and pick them up. He had his ramps built in a hurry and did the best he could.

I believe the ramp that failed was the ramp used for the outlaw too. Not to make excuses, but with the hand he was dealt, Tiger & the LCB did an excellent job. Vive' La Costa!!!

Posted: Sat Jan 06, 2007 4:06 pm
by Eric Brassard
I am thinking in the same way of Wesley, The starting ramp must have a lot of transverse braces. They have to kind of sytarting ramp a Flat ramp and one whit trany. This one whit trany must to have a many braces where the pressure is higher. we use the trany for pumping and accelerate before the first cone. And we can't use a very thick plywood. For the flat ramp we use a plywood 3/4 inch. But we don't have any excuse ( Whit normal utilisation) the ramp break since a race. Please make a test before the cace



Eric Brassard
( Québec Ramp)

Ramps: Make them stronger or reduce the abuse -- or both.

Posted: Sat Jan 06, 2007 9:03 pm
by Pat Chewning
Donald Campbell wrote:regarding pat chewnings statement:
it should be clear that any ramp should be able to take a whole day's beating,which means going down the ramp or running/skating up the ramp.
if any ramp used at any race can not match that certain criteria IT SHOULD DEFINITELY NOT BE ALLOWED for any kind of race.

these are my words and you should put that statement into consideration to your previous post,pat.
I agree with Donald that one way to ensure against ramp failure is to make them extra-strong.

The other way is to reduce the load/abuse (running up ramp, driving over with vehicle, etc).

Both methods (stronger ramps, reduce abuse) would probably be the best way to go.

Posted: Sat Jan 06, 2007 10:19 pm
by Eric Brassard
Eric Brassard wrote:I am thinking in the same way of Wesley, The starting ramp must have a lot of transverse braces. They have to kind of sytarting ramp a Flat ramp and one whit trany. This one whit trany must to have a many braces where the pressure is higher. we use the trany for pumping and accelerate before the first cone. And we can't use a very thick plywood. For the flat ramp we use a plywood 3/4 inch. But we don't have any excuse ( Whit normal utilisation) the ramp break since a race. Please make a test before the race



Eric Brassard
( Québec Ramp)

Posted: Sat Jan 06, 2007 10:49 pm
by Troy Smart
Wow, do all of you really think that ramps should be made in such a way that they don't break and hurt someone??
Well, by golly, I think so too.

Lets make it an ISSA rule:

ISSA rule # 6789:

The ramp structure shall be sturdy, and sturdy shall the ramp structure be. Not flimsy as liketh paper but sturdy in its condition and robust in it's nature. Also, make it be known that it (ramp structure) shall be made of suitable material. Wood being a suitable material as long as the wood is of a sturdy nature. Steel shall also be permitted (just be careful sitting on it on a hot day). Rock is ok. Styrofoam is out, as are paper towels.


That should do.