Road Cycling - where can I find info re catastrophic frame failures?

Yesterday I posted a question about carbon frames and got some excellent responses. Thanks to all who repsonded and especially to Velocipedio for the encouraging info about the Scattante carbon frame. I was getting totally psyched today thinking that I could actually get that bike and it wouldn't completely break the bank (almost, but not completely).

And then I read on another forum that carbon frames give very little warning before catastrophic failure. Having a frame fall apart while cruising down a hill at 35mph would not be my idea of a good time. In fact, it could very likely ruin my day. So the question is: Where can I find data about frame failures? I'm mostly interested in carbon and steel, but it might be interesting to see data about failures with other materials. I know that carbon frames haven't been around long enough to know what they are going to look like after 10 or 15 years of riding -- or whether they will even last that long. If the frame were to come apart after 10 years of riding the bike a lot, I'd feel like I'd gotten a pretty good ride out of it, gotten my money's worth. But if it came apart all at once while I'm on the bike, well that could be real ugly.

I am curious about frame failure regardless frame composition. I like the ride of my old steel Scott bike, that I have over 60,000 miles on. Most of components are new and the ride/performance is great. I have asked ride friends can my 60,000 mile bike last as long as a Honda car??
They suggested internal corrosion could doom the well maintained bike. So am I waisting my money. I maintain this well used bike because, from bad experiences on airlines; I want to take a bike if airlines trashed, I would be less furious.
So could this bike suddenly be a safety issue? I see no sighns of problems from the exterior at welds and such.

Bikes of all materials are subject to failure. There is a revealing study of frame failure at:

http://sheldonbrown.com/rinard/EFBe/frame_fatigue_test.htm

The failures were mostly due to faults in design or construction, head damage to the materials, or the presence of stress raisers which concentrate stress beyound the design limits of the material. Nothing that isnt already known to a good framebuilder.
I dont think the tests prove anything conclusive, beyond the fact that good frames are better than average frames. The sample sizes were too small.

Even if the frame fails, you are not that likely to crash.

Bikerider, you state that even if the frame fails, you're not likely to crash. Is this true? How can it be true if the frame comes apart while you're doing 20mph on the flat or 35 mph on a downhill? Are you saying that it would start to come apart, you'd feel it and slow down and stop before it actually broke into pieces? I don't know that that's true. I've heard that Al frames can come apart fast enough that you'd crash. And now I'm wondering about carbon. If a carbon frame is coming apart, would it give you enough time to stop the bike? I'm leaning toward buying a carbon frame (as opposed to steel), but I don't want to have a concern about frame failure lurking about in the back of my mind while riding.

Cyclezealot, as far as steel goes, what I've heard there is that it's very unlikely to ever be a safety issue because steel shows signs of failure (cracks, etc.) long before the frame would actually break up. So I'd keep riding that steel frame -- just look it over carefully every once in a while and see if there are any cracks developing. I've also heard that sometimes those cracks may be repairable. I'm riding an 18-year-old frame myself.

Island rider, the frame failures that I have seen tend to be on the welds (sometimes near the chain stays) although there was one fellow who had a cracked frame on the head tube, but he was in fact still riding the bike, and took it to a lbs who noticed it. I would think that if a frame did fail, it would be unlikely that the entire frame would just break in two (there are many welds to break) but rather just a seperation of a single weld, or a appearence of a crack would occur. In that case you would notice it before you had a major crash. Although I guess it is possilbe that a frame could fail and break in two, but I really do not think it is probable. hope this helps :)

VegasDude, thanks. Makes perfect sense now that I think about it. You'd have to have two welds fail at the same time or two tubes break at the same time in order for the frame to come completely apart. Or perhaps one weld failing and that failure putting enough stress on one of the other welds that a second failure would occur. Possible, but probably not very likely.

I think what threw me is the term "catastrophic failure" which I've seen in print regarding frame failures of Al frames. A definition of what "catastrophic" means in this context would be helpful, as well as a description of what actually happened on these catastrophic Al frame failures.

Anway, thanks to all for replying to this post. I will do a little more test riding and then buy that new bike, be it carbon or steel.

Catastrophic failure is a failure mode in which a crack propogates very quickly leading to failure of a structure.
Materials Science: a rapid crack growth in which more energy is available for crack advancement than is needed.

In non-catastrophic failure there may be some bending prior to cracking, or the crack may propagate slowly enough to alleviate the stress.

There are many recorded incidents of cat. failure of carbon bladed Spinnergy wheels (earlier models), several resulting in serious injury. There are concerns about carbon bladed forks and carbon steerer tubes, but I havent seen any documented incidents.

Some good failure info at:
http://www-tec.open.ac.uk/materials/mem/mem-ccf.html