Gob-side entry retention (GER) has been successfully advanced and implemented for several years. Notably, strong economic returns have been realised for different thicknesses of coal seams under near-
China consumes more than 3.6 billion tons of coal every year, accounting for over 60% of the energy consumption. Therefore, the sustainable development of coal mine is a problem needed to be so
Results of testing of a yield frame support having synchronized clutches. Testing of the frames in situ and in a laboratory showed that opposite clutches yield by turn, one after another that is comp
