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bill man, props to you, rick, bentley and all the techies. i love reading about the testing and everyones view. im just giving the stick clip carrying odub a hard time. hes getting soft in his old age.

RRO wrote:bill man, props to you, rick, bentley and all the techies. i love reading about the testing and everyones view. im just giving the stick clip carrying odub a hard time. hes getting soft in his old age.

Sheeeeiiiiiiittttt. Gotten harder in his old age. And smarter.

One other maintenance issue that we use at the Via Ferrata Glue ins. Each fall, I apply a concrete caulk to exposed surfaces around the glue-ins. This will keep most of the rain water away from entering any opening left from the application process and just general maintenance. It is possible water can enter and freeze, thaw, and freeze.

bentley wrote:I am not sure what the goal of these pull tests are but here is something to keep in mind:

All of this pull testing is interesting but completely unrealistic for rock climbing. What is being tested is a static system; there is not a scenario in rock climbing that is static.

Although our testing has provided valuable data in determining the better hardware and installation techniques, Bentley's point on the realism of at least some of the tests is valid. Recent tests have been designed and conducted that are closer to realistic RRG climbing scenarios. Similar tests will be done in the future.

This thread was started to provide info about a new promising glue-in bolt that may become available here in the US. It has many desirable characteristics, and in several ways has shown to be superior in durability, strength, and longevity over traditional hanger brackets affixed with expansion bolts.

The one possible downside of this particular bolt is an unacceptable amount of deformation due to repeated lead falls. We are currently performing realistic tests to see how well they hold their shape under multiple impulse loads.

First off, the new hydraulic pump we use in these tests is capable of producing an impulse load very similar to that produced by a falling climber. Typically, a lead fall produces an impulse over about 3/4 second. This varies a little for different systems, types of belaying, etc. This, of course is very dynamic and very realistic, and definitely not a static test. To do this type of testing, all we need do is determine the magnitude of the force to be applied to the bolt, and then repeat the impulse loading with this value over and over until we are satisfied that the bolt does or does not deform.

So, the 64-dollar question is: What force value do we use?

What we didn't know until last Friday's tests is what a realistic range of forces is created during a real world lead fall. As Bentley accurately points out, there are way too many variables in the system to expect exact numbers. A search of the internet will yield too much data -- much of it questionable or totally erroneous. We decided to do our own falling tests to obtain meaningful data within acceptable ranges by setting up real climbing/falling events with real climbers and belayers on real RRG climbs.

Several well-known, very experienced climbers volunteered to participate in Friday's fall testing. Their identities will not be divulged here. If they choose to disclose this information, it is at their choice.

Data obtained included forces encountered on bolted hangers on which the climber test subjects took falls, heights of falls, and fall factors generated. Because many of you have asked to be informed of the results of our testing, I've summarized the two most severe falls taken - one on "Plate Tectonics" and one on "Super Best Friends."

Plate Tectonics Tests:

Rope - Metolius Monster 9.8 mm dia. with no marker threads. Relatively new with only one short lead fall.
Climber weight - 132 pounds
Belayer weight - 180 pounds
Length of fall - 23.1 feet
Total length of rope from belayer to climber after fall - 62.6 feet
Belayer rose 14 inches.
Force on hanger - 458 pounds (distributed about 65/35 between climber and belayer).
Load cell accuracy - +/- 0.3%
Fall factor - ~0.37

Super Best Friends Test:

Rope - relatively new dynamic with one short fall.
Climber weight - 162 pounds
Belayer weight - 130 pounds
Length of fall - 50.1 feet
Total length of rope form belayer to climber after fall - 129.9 feet
Belayer rose 72 inches
Force on hanger - 502 pounds (distributed about 65/35 between climber and belayer)
Load cell accuracy - +/- 0.3%
Fall factor - ~0.38

Drawing from this data, over the next few weeks we will create impulse loads of different force values and loading times to test the Jim Titt glue-in bolt's resistance to high impulse loading.

Please keep in mind that this is only a small part of our testing picture. No conclusions have been drawn, no standards have been set, and certainly no declarations of any kind of safety factors have been made. We are simply trying to learn what makes a good "bolt."

One subjective note: That 50+ foot fall on "Super Best Friends" was something to see! Whew!

Rick

cool rick.....thanks again...had to be a traddie taking that fall, cause there ain't a sportie out there who would take that fall withou peeing their drawers.

pigsteak wrote:cool rick.....thanks again...had to be a traddie taking that fall, cause there ain't a sportie out there who would take that fall withou peeing their drawers.

Nope. It was a sportie.

R

Cool! Thanks to the guinea pigs!

I have to say that I'm not too surprised at how low the max. loads are on the bolt. (Given that trad gear can hold similar falls, even in sandstone) The Climbing Wall Industry Group talks about bolts resisting test loads in the range of 3,000 to 4,000 lbs, so it looks like indoor walls are designed with a pretty big safety factor.

I wouldn't actually suggest doing such a test with real climbers, but I would love to see what happens with a lot less rope and worse fall factors (I'm thinking of a situation where the third clip is blown and the climber falls onto the second bolt, for example)

actually, tom's scenario is 90% of the falls taken around here. most folks see the bolt at their waist or knees, freak out and yell "take". this results in a hard short fall onto the bolt, or a nylon burn from grabbing the runner.

We had bolts like that all over the place in Austria (or at least they looked like that on the surface). Never seen any problems... and the cool thing, if you wanna bail out in the middle of the route just put the rope through it without destroying the rope

ouch wigal..what about destroying the bolt?