Probe-hole drilling: High-stress detection in coal

Technical Report · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6836262

McDonnell, J P; Haramy, K Y

Coal mine bounces and bursts are major problems facing U.S. mine operators. Bounces and bursts have the potential to inflict severe injury on mining personnel, damage equipment, and cause mine closures. High-stress conditions, at or near the working face, are the common denominator in the burst problem. If mine operators can locate high-stress and potentially burst-prone zones, they can then use stress-relief methods to control the burst condition. One method of locating the high-stress zone is the probe-hole-drilling or drilling-yield method. Probe-hole drilling is used frequently in Europe, the U.S.S.R., and Japan as a means for locating potential burst zones. Consequently, the Bureau of Mines performed tests in the laboratory and in a deep, burst-prone western mine to analyze probe-hole drilling. The in-mine method, very simply, involves drilling a hole into the coal seam and measuring the volume of cuttings obtained. A certain volume of cuttings can be expected from a certain diameter and length drill hole. A significant increase in the volume of cuttings means the zone around that particular hole is highly stressed. In-mine use of the drilling yield method has shown it to be a useful tool for locating highly stressed and potential burst zones. Results from laboratory testing confirm that high stress applied tri-axially to a cube specimen will cause a significant increase in the volume of cuttings from a small-diameter drill hole in the specimen.

• Research Organization: Bureau of Mines, Pittsburgh, PA (USA)
• OSTI ID: 6836262
• Report Number(s): IC-9179
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
012010* -- Coal
Lignite
& Peat-- Mining-- Planning & Surveying-- (1987-)
BOREHOLES
CAVITIES
COAL MINERS
COAL MINES
CUTTINGS REMOVAL
DATA ANALYSIS
EVALUATION
EXPLORATORY WELLS
INJURIES
LABORATORIES
MINERS
MINES
MINING
NATIONAL ORGANIZATIONS
NORTH AMERICA
PERSONNEL
PLANNING
RELAXATION
REMOVAL
ROCK BURSTS
STRESS ANALYSIS
STRESS RELAXATION
UNDERGROUND FACILITIES
UNDERGROUND MINING
US BUREAU OF MINES
US DOI
US ORGANIZATIONS
USA
WELLS