Access road in rocky terrain: skid steer or mini excavator?

[fjcruiser]

My vote... Rent the biggest excavator you can with a blade. You kinda get the best of both worlds. You can did out the big rock with the bucket/thumb, then blade/grade through the loose areas quickly.

 

[Citydude]

At a over a quarter mile, at roughly a 35% grade, you need a dozer. A mini ex wouldn't cut the mustard...

 

[BKBoiss]

My vote... Rent the biggest excavator you can with a blade. You kinda get the best of both worlds. You can did out the big rock with the bucket/thumb, then blade/grade through the loose areas quickly.

Exactly what he said. ^^^^

 

[Ken45101]

My vote... Rent the biggest excavator you can with a blade. You kinda get the best of both worlds. You can did out the big rock with the bucket/thumb, then blade/grade through the loose areas quickly.

Do large (e.g. full size) excavators come with blades? I've only seen blades on mini and small to medium size excavators.

 

[Ken45101]

Are you sure about those numbers? Because if that's right, you are making an incredibly steep road. Drainage is going to be an issue. In fact, just getting up and down with a load in the best dry summer weather is going to be an issue. In the Rockies that ill be a summer-only road, right?

Of course any job can be done with small equipment - it just takes longer. But even with modern equipement your time for this job seems way low. I doubt that the skidsteer or that tiny excavator you are looking at will do much. For reference, that size excavator will dig well in dry ground but not at all in rock. Rocky Mountain often means fractured granite rock right starting a few feet under the surface.

You ask about the capability of that size excavator.... For moving & stacking rocks - with a thumb - that size excavator will move and stack rocks up to medium suitcase size all day long with ease, It will struggle hard with footlocker sized rocks but can eventually get one end up and tumble them into position even if it can't actually lift them. Anything larger is too much to do much with. About the only job worse than what you are describing would be if you were trying to put that road across a rocky side slope. Doing that would be much harder & take longer even though not as steep when finished.

As described, I'd recommend a dozer with 6way blade and a skilled local operator to do the cutting plus something with a bucket to move dirt. And even so allow more than 2 or 3 days. And if you can find some way to make the road twice the length for that rise you'd have a better chance at using it in the winter. Not trying to discourage you, just being realistic.
rScotty

You are probably right on the time estimate being low. I had our driveway widened by 2ft and it took a week for about 800 feet. It was cutting into fractured shale.

 

[EddieWalker]

Do large (e.g. full size) excavators come with blades? I've only seen blades on mini and small to medium size excavators.

Deere has a 20 tonne machine that you can get a blade on, and Volvo has a 30 tonne excavator with a blade, but they are both going to be hard to find. Much easier to find a 14 to 15 tonne machine with around 100hp with a blade that would be ideal for something like this.

 

[EddieWalker]

Hey Eddie, here It's not individual rocks in dirt like central Texas - or even layered shelf rock like Lampasas County. What we've got in the Rockies is usually a layer of fractured and disintegrating granite down for a couple of feet under a foot or so of what we call "top soil" but is really just mostly rotted pine duff. The disintegrating granite (DG) has been broken up by water/freeze cycles and so it is pretty easy to fracture it farther and scrape it out with construction type machines. The DG can be scraped out by a skilled dozer or excavator....even a backhoe. But that's about as far as we can go because only a few feet farther down we get into the same stone but unweathered. That is what is called "competent granite".... which means all one piece and not fractured. No way can you do anything to it. That's the rock that forms the backbone of these mountains. Then nothing but blasting will work.
rScotty

Thank you, that was my original thought on what the ground would be like, but then people started talking about the mini ex not being able to dig out the rocks. If it can't dig out the rocks, then a dozer is just going to have more trouble getting them out of the ground.

 

[CADplans]

The bucket on a big excavator is almost the same size as the blade on a mini-ex,,,

This excavator did a beautiful job on my road,,

I think the only reason he brought the CAT was so that his dad would have something to do,,,

Virtually 100% of the earth moving was done by the excavator,,

Big rocks did not slow the excavator down,,

He just picked them up and put them where he wanted to,,,