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Rock Armouring Examples for reference

moggio's picture

By moggio - Posted on 30 December 2010

I often rant on about rock armouring and how good some of it is at You Yangs near Melbourne. Well I stumbled on some pics I took there recently and thought I'd put them up for reference.

What is so great about this rock work is that it really anchors things together on some quite steep sections, but also is great fun to ride. It is also bi-directional... though up on some this is reserved for the expert rider.

I am sure you can imagine a few of the eroded pinches at Knapsack where an apporach like this would be great for holding everything together yet still maintaing the fun factor.

BM Epic's picture

Oh god i am drooling, reminds me of why i love riding rocks, just did Mt York yesterday and got reminded of my love of good tracks with lots of rock!
Love it Mark!

ChopStiR's picture

I can think of a few spots this would be helpful

Nerf Herder's picture

The most important bits are the corralling rocks and brush mapping / barriers IMO.

Need to really think about how rough and what barriers we place to keep people on track nothing worse then having all this awesome armour and rock work only to have it sitting next to an eroded and under cut section that people have created to bypass the "hard" bits.

I know you shouldn't ring the tracks with logs and rocks etc ... however, I just can't get my head around how to stop people taking the lines of lease resistance. May need to either compromise (and use the logs/ rock fencing in approach) and or do some more research on how others have dealt with this challenge.

I vote for lots of rollers & berms to pump on too Smiling

Flynny's picture

Logs and rocks are fine for corralling riders on to the main line, Al, you just need to do it right and think about crash and run off zones and stuff like that. Think about where to put the obstacle that makes the line you build the best one to ride.

It's when you line the sides of the trail, ie have raised log lengthwise along an entire section of trail (IMBA's "Paving a trail to grandmas house") where it gets bad as they only serves to trap water as force it down the trail.

I like to make my trails as natural as possible and use strategic rock armouring, ie rather than rock armour an entire slope put in some stuff to brake the rut, obstacle to get riders off the brakes and then heavily rock armour any braking zone near at bottom

Kingy's picture

Love this stuff brilliant!

moggio's picture

I just want to bounce this one because I like the rock armouring and thinking a lot about that stuff at the moment.

Kingy's picture

It is the ultimate in sustainable design

Nerf Herder's picture

The flatter sections of Stringline now and also OBR don't have major issues requiring hardening.

Steeper, straighter and naturally rocky sections will obviously benefit from Armouring ... however, because we've specifically reduced the gradient and have several traverses ... we should be able to minimise the amount of artificial armouring "of the tread" and use gradient reversals instead I would have thought.

What do you reckon ... I think we avoided pretty much any fall line sections, except at the switch backs ... which is probably limited to 2 meters at most.

There will be plenty of rock work with benching and corners though Smiling

hathill's picture

Scissors, paper ROCK!

moggio's picture

Yeah a lot of the trail has a low enough gradient (remember my protractor with the green string Smiling ) that it won't need much armouring, however with the sandy soil we will have to do the full-cut bench rather than a cut-fill bench. If not possible in areas we would need to have the fill be mainly built up on rock.

The only real tricky areas are the switchbacks. There are really three types there 1) Ones that drop down over solid rock which will need a little rock forming probably to transition to them in places 2) There is I think one that could be handled like a rolling crown or just a bermed one that is flat enough to handle this and 3) a few that will need to be rock armoured somewhat like the first phot above, which is actually really steep.

Further down under the power lines where it is heavily degraded land and classified as such we will need to armour just to hold some of it together I think. There is one bit on an existing old forgotton walking trail section that is steep that would be great as a "rock garden".

Of course rock is best where the gradient is reasonable as you get enough speed to bounce over it.. on the flat and up it becomes nasty.

I think also the rock will just make it more interesting to ride, slow people down a bit while being more entertaining thereby "extending" the trail length, at least in time to ride.

Once again have a look at this document from CTMTB and their new track for the SCA approvals

Nerf Herder's picture

cool ... I was think of that bit down the bottom under the power lines too.

Can't wait to see the switch backs Smiling

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