ROCK MASS RATING SYSTEM FOR FLOOR STRATAOF KARST TYPE COAL MINES AND ITS APPLICATIONTO WATER INVASION CONTROL

doi: 10.3969/j.issn.1001-4810.2000.03.007

• Wang Jingming¹ , 
• Deng Xiqing² , 
• Wang Houhuai² , 
• Tong Hongshu² , 
• Zhang Yongtai²

• 1.

  China Coal Research Institute, Xian Branch , Xian

• 2.

  Wanbei Coal Administration, Suzhou