In connection with common accidents in constructive pr ocess of steel bar & concrete prefabricated pile,it analyzes cause of its accide nts from aspects of split on top of the pile?broken body of the pile?slippery or translocation of the pile & gush of the pile and puts forward concrete handli ng methods & preventive measures so as to be references.

Prevention and control technology for spalling and failing of high inclined broken roof in fully mechanized mining face;

Research on broken roof consolidation technology in coal ming face;

Mechanism and project practices on broken roof control with wood bolt in fully mechanized coal mining face;

Cause analysis on roof broken in mine gateway retained for next sublevel in Xinghua Mine as well as prevention and control;

Based on the geological conditions and numerical simulation, the hard rock roof blasting method and blasting parameters were proposed to prevent rock burst.

Application of supporting technology combination of anchor cable and bolt in friable roof support;

Drecting to the difficult controlling problem of friable roof in blasting coal face near the gob area and based on the conventional longwall mining method, Sihuaishu Coal Mine succeeded in the extraction of No.