Aiming at the problem that the roof disaster easily occurred before the lower coalface went though the upper goaf or the mining activity was just below the goaf,the authors proposed corresponding solutions,such as partial filling,etc.

Puts forward the concept of synthesis earthquake disaster control appraisal index,Design and train this index based on artificial nerve network then carry on analysis and estimate.

By summing up the commonly seen hazard type of break-in and break-out in the analysis of mechanism of hazards,three aspects are stated for hazard control research,while feature and inadequacies are also pointed out,followed by some new research ideas and issues on-site being put forward to be studied.

Discussion about roof control technology development of China in future;

The roof control technology of combined machinery island face in Jining No.2 Coal Mine;

The selecting type of the support and roof control in soft rock coal seam floor