Based on simulating model test and theoretical analysis,the mechanism of main roof first breaking is revealed,and the asymmetry breaking parameter is determined.

Study on load transmitting factor of thick sandy soil on key roof stratum during first weighting in shallow seam;

The first weighting of the main roof is the very fierce ground behaviour.

Combined with the geological conditions,theoritical prediction of first caving distance,first weighting in old roof and circular weighting distance are made,which is coincided with mining practice and effectively supply a guidence for the mining in 88101 face of Kangjiatan mine.

Solvent swelling: A new technique for oil primary migration;

Quantitatively evaluating hydrocarbon primary migration by mudstone compaction dynamic analysis;

With the study on the moving law of the surrounding rocks in the seam mining processing of the fully mechanized coal mining face in 4-2 seam of Fengshuigou Mine,the paper understood the initial pressure and the periodical pressure distance of the 4-2 seam roof pressure,the support strength of the hydraulic supports in the coal mining face,the stress variation and stress a.

Technology and control of first roof caving in coal working face;

Practice of first roof caving technology at comprehensive mechanical mining face in steep thick coal seam;