…with rocks bars and rocks. (grip hoist and excavators not available)
When did the advantage of using a lever first become apparent? Was the knowledge handed down by word, until finally written? I’m not sure, but rock bars are a staple tool for leveraging advantage for trail work in rocky areas. As shown in the image below, the ratio of the load arm to effort arm determines advantage, the most advantage being achieved from using the shortest load arm length practicable.
One of the harder tasks encountered in trail building is getting rocks, or better yet “boulders,” out of holes. Sometimes a rock has to be (re)moved or harvested for use elsewhere.
It’s a hard task made simple, but maybe not easy:
Start replacing the boulder’s home/hole with small rocks to slowly pry and jack it out of its home– replacing is home with small rocks…trading places. The small rocks are used as fulcrums to help lift the rock, adding more as the rock is lifted until its ejected.
A griphoist can drag rocks out of a hole, but in all likelihood rock bars will be needed to allow it to be strapped with slings. In probably less time than a drag-line and slings can be set up the rock could be removed with bar(s) and rocks alone (assuming jack rocks are readily available).
Speaking of “jack rocks,” another method of jacking rocks out of holes is to use a car jack, or two…Hydraulic jacks may not work when tipped or angled from positions other than horizontal, and could prove to be quite dangerous compared to scissor jacks should they fail. Know the load bearing capacity of the scissor jack. Most rocks are about 600-800 lbs/cubic ft.
If you’re desperate and don’t have a rock bar or two then sticks and logs might work. I’m guessing the first rock bars were wooden. These people keep that tradition alive, used jack rocks, and a car jack (story):
Using this bag for rocks instead of a car might damage the bag, but I gotta give em’ points for ingenuity: