METHOD FOR DETERMINING RANGE OF DANGEROUS ROCK FORMATION OF ROADWAY CEILING

• Main Authors: TAN, Yunliang, ZHAO, Tongbin, YU, Fenghai, GAO, Xuepeng, YIN, Yanchun, ZHAO, Wei
• Format: Patent
• Language: Chinese; English; French
• Published: 25.07.2019
• Subjects: EARTH DRILLING; FIXED CONSTRUCTIONS; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER,MECHANICAL EFFICIENCY, OR FLUID PRESSURE; MINING; PHYSICS; SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, ORDRAINING IN OR OF MINES OR TUNNELS; TESTING

A method for determining a range of a dangerous rock formation of a roadway ceiling comprises: selecting a region where a tested pulling force limit is less than 1.2 times a designed support body anchoring force; in the selected region, and within a range no more than 0.5 m away from the support body of the pulling test, arranging drilling holes and drilling to obtain a drilling speed per meter, performing comparison to obtain a fastest drilling speed and a slowest drilling speed, calculating a ratio of the drilling speed per meter to the slowest drilling speed, and obtaining a ceiling rock formation range in which the ratio is greater than 2.0; performing detection on a ceiling drill hole using a drill hole imaging apparatus, obtaining a schematic diagram of ceiling crack distribution, and obtaining a ceiling loose material and crack range; and comparing the ceiling loose material and crack range with the ceiling rock formation range in which the ratio is greater than 2.0, so as to determine a ceiling rock f