Consider a vein of medium width (50 ft, 15.2 m) that dips 65? and is mined by

Question:

Consider a vein of medium width (50 ft, 15.2 m) that dips 65? and is mined by vertical crater retreat (VCR), as shown in the sketch for the previous problem. Level interval is 150 ft (45.7 m). Layout a hanging wall cable bolt pattern using two 5/8-in. (1.6 cm) diameter 25 ton (224kN) capacity bolts per hole with toe spacing a maximum of 10 ft (3 m), specify hole angles and lengths. Justify in detail your bolting plan including spacing of bolt fans on strike.