Abstract: According to the problem in coal mining caused environmental pollution, ecological destruction, waste of resources, high cost, charging for the “mining—backfilling—keeping” green mining technology. Analysis of gangue compression rate of different particle size distribution and stress, research the mechanism of gob-side entry retaining technology, And research the concrete filled steel tube supporting technology, the “mining—backfilling—keeping” green mining technology is feasible. Filling gangue particles with diameter less than 2.5mm in the gangue powder content accounted for 5%, particle size less than 45mm accounted for 15%, more than 45mm of waste rock accounted for 80% of the best particle size gradation. Gob-side entry retaining use anchor beam on forepoling, concrete filled steel tubular columns with gangue bags roadside support walls to maintain the stability of roadway and control deformation of the surrounding rock plays an important role. The technology has important guiding significance to green mining, has the important value of promotion and research.

Key words: “mining—backfilling—keeping&rdquo, green mining technology particle size distribution concrete filled steel tube