Close-distance coal seams (CDCS) are widely distributed, and the layout of the upper and lower panels can be divided into "=" type and "+" type. The "+" superposition of upper and lower coal pillars in CDCS caused strong mine pressure, but there are few studies on the panel crossing residual coal pillars (RCP) when the upper and lower coal seams are "+" type layout. In view of the special spatial position ("+" type layout), this paper takes the typical panel 4-301 of a particular mine as the project indagation background and studies mining and crossing the overlying coal pillars by dint of field measurement, numerical simulation, indoor test, and engineering application.
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