Key;
Laboratory;
of;
Geomechanics;
and;
Deep;
Underground;
Engineering,;
China;
University;
of;
Mining;
&;
Technology,;
Xuzhou;
221008,;
China;
of;
Mechanics;
and;
Civil;
Engineering,;
China;
University;
of;
Mining;
&;
Technology,;
Xuzhou;
221116,;
China;