The support stability mechanism in dip direction of fully mechanised working face with big dip angle considering the strike angle

The 'support - surrounding rock' mechanical model has been set up to solve the stability control problem of fully mechanized working face (FMWF) with big dip angle. By the mechanical analysis of SSIDD of working face with big dip angle (WFBDA) in a free state, operating state and special state, we have found the mechanical relationship of critical topple/slip angle with support height, width, resistance and friction coefficient. With the research results applied to #115011 FMWF of Wangwa No. 2 coal mine, the following data have been figured out: in a free state, the critical topple/slip angle of the support are 21.51 degrees and 4.88 degrees. In a special state, the two figures are respectively 64.61 degrees and 39.94 degrees. Thus, the critical support resistance required for the support not to topple or slip is 4,855 kN and 6,591 kN respectively. By movable side guide plate and other technical measures, we realize the safe and efficient production of working face.