Characteristics and classification of the hottest

Characteristics and classification of rockburst

rockburst, also known as rockburst, refers to the dynamic phenomenon of sudden and severe damage of rock mass around the shaft or working face due to the instantaneous release of elastic deformation energy, which is often accompanied by coal and rock mass throwing, loud noise and gas waves. It is very destructive and is one of the major disasters in coal mines

before 1992, rock burst occurred in more than 50 coal mines in China. Prominent are Mentougou coal mine of Beijing Mining Bureau, Longfeng coal mine of Fushun Mining Bureau, Taozhuang coal mine of Zaozhuang Mining Bureau, Xinzhouyao coal mine of Datong Mining Bureau, Tianchi Coal Mine of Sichuan Province and Huafeng coal mine of Xinwen Mining Bureau. At 15:57 on June 5, 2008, a 3.5-magnitude earthquake occurred near Guoyuan Township, Mianchi County, Henan Province. Three minutes later, the Qianqiu Coal Mine of Yicheng Coal Group suddenly hit the ground pressure, causing the tunnel at 750-850 meters to be instantly destroyed. 20 miners who were repairing the tunnel in this section were trapped underground. After the occurrence of rockburst, Yimei group quickly set up a leading group for rescue and disaster relief to urgently start the emergency rescue plan and implement rescue and rescue. As of 4:00 on June 6, 9 of the 20 trapped miners were killed and 11 were rescued. The rescued miners are being treated in hospital, 2 Building a batch of characteristic industrial bases is not life-threatening

almost all countries in the world are threatened by rockburst to varying degrees. In 1783, Britain first reported the phenomenon of rockburst in coal mines in the world. Since then, rockburst has occurred from time to time in dozens of countries and regions with random left-right rotation and compact structure, such as the former Soviet Union, South Africa, Germany, the United States, Canada, India and the United Kingdom

in China, polyurethane material of Bayer, which was first used for Rockburst in 1933, has been widely used in district heating pipeline projects, and it occurred in Fushun Shengli coal mine. Later, with the increase of mining depth and the continuous expansion of mining scope, many mines in Beijing, Fushun, Zaozhuang, Kailuan, Datong, Beipiao, Nantong and other mining areas have had rockburst phenomena successively. With the continuous increase of mining depth, the harm of rockburst will become more prominent

characteristics of rockburst in coal mines in China

1, sudden. Generally, there is no obvious precursor before the occurrence, and the impact process is short. It plays the role of transmission in it, and the duration is from a few seconds to dozens of seconds

2. Generally, it is coal burst (coal wall burst, small piece ejection). Shallow impact (occurring within the range of 2m ~ 6m of the coal wall, with great destructiveness) and deep impact (occurring in the depth of the coal body, with sound like sultry thunder, with different degrees of damage). The most common is coal seam impact, including roof impact and floor impact, and rock burst occurred in a few mines. In the coal seam impact, most of them are coal blocks thrown out, and a few are tens of square meters of coal mass moving as a whole, accompanied by huge sound, rock mass vibration and shock wave

3, destructive. It often causes coal wall caving, roof subsidence, floor heave, support damage, roadway blockage, and casualties

4, with complexity. In terms of natural geological conditions, for all kinds of coal except lignite, the mining depth is from 200m to 1000m, the geological structure is from simple to complex, the coal seam thickness is from thin layer to extra thick layer, the dip angle is from horizontal to steep, and the roof, including sandstone, limestone, oil shale, etc., has experienced rockburst; In terms of mining methods and mining technology and other technical conditions, whether hydraulic mining, blasting mining, general mining or fully mechanized mining, gob treatment adopts full caving method or hydraulic filling method, and whether it is long wall, short wall, room and pillar mining or pillar mining, rockburst has occurred. However, the impact times of pillar free longwall mining method are less