Mine roof vibrations from underground blasts

Technical Report · Thu Jan 01 04:00:00 EST 1970

OSTI ID:5308777

Olson, J J; Dick, R A; Condon, J L; Hendrickson, A D; Fogelson, D E

Previous Bureau of Mines studies of vibrations from quarry blasts have shown that the square root of the charge weight may be used to group particle velocity data from various charge sizes, and that empirical propagation equations may be used to estimate vibration amplitudes. Particle accelerations of the sandstone roof of the White Pine Copper mine, Michigan, were measured to determine whether similar propagation equations may be developed for underground mine blasts. Vibration data from White Pine blasts were best grouped by scaling with the square root of the charge weight. Vibration differences among headings and types of explosive charge (AN-FO and dynamite), while statistically significant, were not a major factor in the estimation of maximum vibration amplitudes with an empirical propagation equation. Vibration differences between types of explosive charge were larger than the differences among headings, indicating that some reduction of vibration amplitude might be gained by using AN-FO rather than dynamite. Acceleration records from both White Pine's AN-FO and dynamite production blasts show that high intensity vibrations from the delayed portions of the blast (each delay interval = 25 milliseconds) were separate events, and that the zero-delay portion of the blast produced the maximum vibration amplitudes. If the pull of the underground blast round can be maintained, a reduction of the zero-delay charge weight may effectively reduce the maximum vibration amplitude of the blast.

• Research Organization: Bureau of Mines, Washington, D.C. (USA)
• OSTI ID: 5308777
• Report Number(s): BM-RI-7330
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
422000 -- Engineering-- Mining & Underground Engineering-- (1980-)
45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
450100* -- Military Technology
Weaponry
& National Defense-- Chemical Explosions & Explosives
ACCELERATION
CHEMICAL EXPLOSIVES
COMPARATIVE EVALUATIONS
EXPLOSIONS
EXPLOSIVES
MATHEMATICAL MODELS
MECHANICAL VIBRATIONS
MINES
MINING
ROOFS
UNDERGROUND MINING