<正> Based on the construction project of the Changjiashan tunnel of the freeway,the variety rule of surrounding rock masses of the tunnel through the gob of co
<正> The mechanical principle and surrounding rock deformation feature of highstress coal roadway was analyzed.The condition of stress balance of the kind of th
<正> To solve the issues of calculating gas loss quantity during sampling,simulated gas desorption process of the consumingly destruct coal with the assembly si
<正> On the basis of investigation and research on the pollution source and pollution pathway of Yujiagou area,by the ground water quality analysis and the leac