The Unofficial
I-26 Construction
Madison County
North Carolina


A drilling rig works on a final cut slope drilling a rock bolt hole. Rock bolts come in two types; one is just a long metal rod inserted into a hole and grouted in place. The other is a long metal rod that is actually anchored into place in the hole, grouted, and then subjected to a test to make sure the rod doesn't easily come out. The final slope shows the presplitting holes drilled into the rock initially; they are the grooves running down the slope. The slope is lowered in "lifts"; each lift is about 15' high and the next one cannot be begun until the rock bolts are put into place. Rock bolts are used to pin the slope together when small fracture planes are found after a rock cut is begun. Photo taken October 1998.



 John Lansford
23 November 1998