The left-hand rolling-thread steel bolt has been proposed as a new bolt for controlling roadway surrounding rock. To explore the mechanism of a left-hand rolling-thread steel bolt in roadway surrounding rock control, its pretightening forces, tensile strengths, anchoring forces, and maximum working resistances were compared to normal right-hand full-thread steel bolts in the engineering context of the 1301 haulage roadway in the Daxing Coal Mine. Then, the left-hand threaded steel bolt was applied to the 1301 haulage roadway that the right-hand threaded steel bolt failed to control. The results indicated that due to the different effective tensile section area, the yield strength and tensile strength of the left-hand threaded steel bolt with the same material and diameter were more than 10% larger than those of the right-hand threaded steel bolt. Due to the different thread directions, the anchoring forces of the Φ18 and Φ20 left-hand threaded steel bolts were 46.2% and 33.3% greater than those of the right-hand threaded steel bolts, respectively. In the 1301 haulage roadway, the maximum pull-out force of the left-hand rolling-thread steel bolt with the same diameter was obviously greater than that of the right-hand full thread steel bolt. The displacements of the 1301 haulage roadway supported by the left-hand threaded steel bolt were not great. So, the left-hand threaded steel bolt can effectively control the surrounding rock in the 1301 haulage roadway.

The surrounding rock control is a tough issue in the roadway with the swelling soft rock. The steel set is an important material for the control of swelling soft rock roadways. However, traditional steel sets failed to prevent the expansive pressure of the soft rock. Based on traditional steel sets, this paper developed a new steel set through both theoretical analysis and numerical simulation. The results showed that the new steel set was the set with the roof beam 1000 mm from the top of the set and the floor beam 400 mm from the bottom end of the set. The maximum deformations of the roof-floor and two sides of the ventilation roadway controlled by the best-improved set at the observation point were 147 mm and 108 mm, respectively. So, the best-improved set can effectively control the surrounding rock of the ventilation roadway. This provides an effective method for the surrounding rock control in extremely soft rock roadways.

Close-distance multilayer coal mining is common. Under the condition of extremely close-distance coal seams, it is extremely difficult to control the surrounding rock of large-span open-off cut roadways in multistress concentration areas. Based on the engineering background of the 23616 open-off cut roadway in Chaili Coal Mine, this paper investigated the influence of upper close seam mining on the stress and deformation of the lower large-span roadway in detail. The control effect of a high-strength prestressed yielding bolt and cable was analyzed systematically. The support system stress was coordinated by the yielding member to avoid excessive stress on the local support structure and reduce the stress concentration of the surrounding rock. Before and after the upper coal mining, the stress changed mainly on the left and right sides, and the displacement changed mainly on the right side and roof. The maximum deformation of the roof and the right side and the left side at two engineering observation sections was 85 mm, 61 mm, 48 mm and 68 mm, 53 mm, 46 mm, respectively. The surrounding rock control effect was relatively ideal, which can meet the needs of roadway installation support.