Abstract：The mechanical situation of the roadway is different from that of average gateway. On one side of the roadway is the relative integrated coal seam and on the other side is the narrow pillar in which plastic deformation has occurred. The high abutment pressure zone on the integrated coal beside the roadway will occur due to superposition of the advancing abutment pressure in front of working face and the concentration stress of the goaf side in the course of extraction. The stress on the integrated coal is much greater than that on any side of the average gateway. The stress distribution in surrounding rocks and floor heave process of roadway driven along next goaf is analyzed by numerical simulation. It is supposed that when the roadway is near the next goaf，the floor is not affected by the horizontal stress，and the floor heave is formed because the floor rock moves into the interior of the roadway along next goaf under high stress on coal mass side. The narrow coal pillar may control elevation of the floor. The control technique of floor heave is introduced and applied to engineering practice.
