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I was curious if anyone knew of a site or the formula to determine what the percentage of grade a climb would be. I have a local park that has a steep (at least to me) climb that I am using for exercise and I am just curious. Also it would be nice for me to be able to compare the percent grade of that to various climbs on the AT.
Here are the numbers. The trail is 760' long and has an elevation gain of 225'. Thanks.
Rex
Alligator
01-06-2007, 14:41
Percent grade=rise/run*100
(225/760)*100=29.6~30%
Frolicking Dinosaurs
01-06-2007, 14:46
Somebody beat me to it.
Purchase a clinometer (http://en.wikipedia.org/wiki/Clinometer) and you can avoid the math. Trail designers use them all the time.
A 30% grade is pretty darn steep! Most trails are 10% or less, or should be anyway.
Most of the AT has at least 100% gain in elation, when compared to civilization. Some areas, such as the Whites, Maine, the Nanathalas, the Smokies, and even a few hostels have an almost 300% elation gain.
The Old Fhart
01-06-2007, 15:04
I was going to disagree with ScottP but after reading his post again, he is actually right!;)
Alligator
01-06-2007, 15:06
Purchase a clinometer (http://en.wikipedia.org/wiki/Clinometer) and you can avoid the math. Trail designers use them all the time.
A 30% grade is pretty darn steep! Most trails are 10% or less, or should be anyway.Some compasses have them built in.
I have a local park that has a steep (at least to me) climb that I am using for exercise and I am just curious.
Rex
Rex:
I'd be curious to know how badly eroded that trail is.
Frolicking Dinosaurs
01-06-2007, 15:37
I did the math and came out with an average of 39.45 degree angle on that trail :eek: There are staircases that aren't that steep!
Rex:
I'd be curious to know how badly eroded that trail is.
The lower portion is getting eroded quite badly. The upper section actually has stairs, if you will, made out of cut railroad ties. This is in a town park and has a very nice overlook platform with benches at the top. One of our Scouts is considering placing water bars (not sure what the real name is) at the lower end to try and slow down the erosion.
Rex
. One of our Scouts is considering placing water bars (not sure what the real name is) at the lower end to try and slow down the erosion.
Rex
The best thing to do would be to relocate the trail and put in switchbacks. The water bars (you got it right) are just bandaids for a poorly designed trail. But if there is not the land or resources for a relo, water bars are better than nothing. They will require constant maintenance however.
Under 200 feet per statute mile, it's an easy grade. Anything much above 600 or 700 feet per mile is tough, at least for me.
Roughly 700 feet per mile is about a 7.5 degree grade.
The profiles on the official AT maps tell you (almost) all you need to know. Unfortunately they're not so good at prediciting "noise". Ie., many little ups and downs take as much out of you as one big one.
The profiles on the official AT maps tell you (almost) all you need to know. Unfortunately they're not so good at prediciting "noise". Ie., many little ups and downs take as much out of you as one big one.You said it well terrapin. I often find those elevation profile breakdowns to be deceptive. I guess in the end it is what it is, and no numbers or maps can tell all.:) Thats part of the fun.:cool:
I guess in the end it is what it is, and no numbers or maps can tell all.:) Thats part of the fun.:cool:
Yep. No point looking too long or hard at those profiles. You gotta walk whatever the trail dishes out, anyway. Sometimes it's best not to know, and be pleasantly surprised when you reach the top. Same reason why I don't really want an altimeter watch.
Programbo
01-14-2007, 22:17
I`m sure someone has asked this already..BUT..Using this formula is the AT more uphills South>North or North>South?
4eyedbuzzard
01-14-2007, 22:42
I`m sure someone has asked this already..BUT..Using this formula is the AT more uphills South>North or North>South?
Baxter Peak/Katahdin 5266 ft asl
Springer Mountain 3280 ft asl
Therefore it is obviously downhill if one starts in Maine.
Of course, given what amounts to almost 90 verticle miles in climbs, or in other words almost 1 million feet in cumulative elevation change(sum of uphill and downhill) over the length of the trail, it's kind of a moot point. Yet even given all those lung busting ascents and ligament stretching decents, the AT is actually relatively flat, as it has an average grade of only 4%, or 2 degrees.
Given the oblate shape of our planet, I think it rather obviouos that a SOBO walks uphill the whole way.
4eyedbuzzard
01-14-2007, 23:15
There is a lot to be said for the good old days of believing in a flat earth. It sure made the math easier.
Percent grade=rise/run*100
(225/760)*100=29.6~30%So if the rise was 760 feet over that same distance, the grade would be 100%?
Seems to me that the grade would be just 45 degrees.
:-?
[/URL]
Here are the numbers. The trail is 760' long and has an elevation gain of 225'. Thanks.
[URL]http://www.easycalculation.com/area/triangle-angles.php (http://www.easycalculation.com/area/triangle-angles.php)
The answer is 16.49 degrees
:banana
4eyedbuzzard
01-14-2007, 23:45
So if the rise was 760 feet over that same distance, the grade would be 100%?
Seems to me that the grade would be just 45 degrees.
:-?
You are correct. A 100% grade is an angle of 45°.
http://urbanworkbench.com/baffled_by_degrees_minutes_seconds
Toolshed
01-14-2007, 23:47
[/URL]
[URL]http://www.easycalculation.com/area/triangle-angles.php (http://www.easycalculation.com/area/triangle-angles.php)
The answer is 16.49 degrees
:banana
You beat me to it!!! Here (http://geology.isu.edu/geostac/Field_Exercise/topomaps/slope_calc.htm) as well.
Discussion is percent of slope versus angle of slope....
Thanks 4eyedbuzzard!
Yet another day I leaned something here on WhiteBlaze!
Hence force I will forever be describing my hikes in terms of percent grade, rather than in terms of an angle.
It definitely sounds a whole lot scarier to describe the last section of Trail before the Tableland as a 100% grade, rather than just a 45 degree climb!
:banana:banana:banana
4eyedbuzzard
01-15-2007, 00:08
Another problem here is that trail length is generally the hypotenuse, not the adjacent leg or "run" in a grade/angle equation.
[/URL]
[URL]http://www.easycalculation.com/area/triangle-angles.php (http://www.easycalculation.com/area/triangle-angles.php)
The answer is 16.49 degrees
:banana
Actually, 17.22 degrees; the hyp. is the trail
I get your angle, Groucho. :)
Kerosene
01-15-2007, 12:09
Wow, and here I've been telling my high school daughter that there is only one correct answer to choose for the math SAT!
This is also a great case study that not everything you read on the Internet is true! ;)