Crater testing has been conducted at a mine site. The explosive parameters and the test results...

Transcribed Image Text:

Crater testing has been conducted at a mine site. The explosive parameters and the test results are given below: ANFO: SG 0.8, 66"x36" charge = Test Results: Charge Depth (ft) Crater Volume (ft) 3 245 5 410 7 495 8 510 9 500 11 430 13 270 15 0 1) Plot charge depth vs. crater volume, and determine the optimum depth do and the critical depth N. 2) Use both weight crater method and volume crater method to find out the optimum charge weight to pull 20 ft. of burden. Select an appropriate borehole size for the blast. 3) Plot both K(A) vs d/N and K'(A) vs K(A). 4) Another shot is made on the same site using gelatin dynamite: SG = 1.5, q6"x36", d = 10 ft and V 1200 ft. Find out the optimum depth do and the critical depth N for gelatin dynamite in = this rock formation. 5) Use volume crater method to find out the optimum charge weight to pull 20 feet of burden using gelatin dynamite. Also select an appropriate borehole size for the blast. Crater testing has been conducted at a mine site. The explosive parameters and the test results are given below: ANFO: SG 0.8, 66"x36" charge = Test Results: Charge Depth (ft) Crater Volume (ft) 3 245 5 410 7 495 8 510 9 500 11 430 13 270 15 0 1) Plot charge depth vs. crater volume, and determine the optimum depth do and the critical depth N. 2) Use both weight crater method and volume crater method to find out the optimum charge weight to pull 20 ft. of burden. Select an appropriate borehole size for the blast. 3) Plot both K(A) vs d/N and K'(A) vs K(A). 4) Another shot is made on the same site using gelatin dynamite: SG = 1.5, q6"x36", d = 10 ft and V 1200 ft. Find out the optimum depth do and the critical depth N for gelatin dynamite in = this rock formation. 5) Use volume crater method to find out the optimum charge weight to pull 20 feet of burden using gelatin dynamite. Also select an appropriate borehole size for the blast.