Abstract:

Abstract：In view of the severe floor failures of large cross-sectional mining roadway in No.1 Coal Mine of China Coal Pingshuo Group Co., ltd, this article analyzed the conditions of surrounding rock, studied the mechanism of the floor heave in large cross-sectional mining roadway of fully mechanized top coal caving. The combinatorial controlling measures which called “pressure-relief and reinforced supporting” were put forward; these were the specific implementation of excavating pressure-relief cutting and optimization roadway-side supporting. Additionally，through field test of roadway floor damage depth, the digging depth of pressure-relief cutting was determined as 0.6 ~ 0.8 m. Through the engineering tests of the combinatorial controlling technique，the results showed that the maximum displacement and the maximum rate of floor heave were 227 mm and 38.5 mm/d．Thus，the combinatorial controlling technique can effectively control the floor heave and keep the surrounding rock in stable.

Key words: Key words: large cross-sectional mining roadway, the causes of floor heave, floor bolting, pressure-relief cutting, control technology of floor heave