Abstract: The aim of this study is to resolve the present control problems and the corresponding high-strength anchor cable control technology in deep large section roadways. This study was based on the Hoek-Brown criterion and the upper bound theorem of the limit analysis and also considered the stress of surrounding rock in the roof and the effect of supporting the load. On the above basis, the roof caving mechanism of large-section roadways was acquired. Furthermore, a design method for roofs was put forward for the minimum length and the pre-tightening force of an anchor cable. Since the design parameters of anchor cables was affected by established sensitivity indexes, it is important to investigate the effects of established sensitivity indexes on factors, such as the roadway’s width, the specific weight of the rock mass, the stress in the surrounding rock, the compressive strength and the tensile strength of the rock mass, anchor cable layout spacing and vertex anchor cable laying angle. According to the actual field conditions, engineering suggestions are proposed for controlling surrounding rocks in the deep large-section roadway. Finally, this design method was applied to determine the roof anchor parameters of transport gateway of 1305 Island Coal Face in the Kilometer Deep Well Zhaolou coal mine, which effectively controlled the deformation of surrounding rock. From research results, only when the roof anchor cable was anchored in stable rock and enough pre-tightening force was exerted, the roof rock caving and damage can be effectively controlled in high-stress large-section mining roadways. It is found that roof pre-tightening force for anchor cable decreased with the increase of tensile strength, compressive strength and empirical parameter A of rock mass. Besides, this roof pre-tightening force increased with increasing the width of the roadway, the specific weight of rock mass, the stress in the surrounding rock, the compressive strength and the tensile strength of rock mass, anchor cable layout spacing, vertex anchor cable laying angle and empirical parameter B of rock mass. Moreover, the highest sensitivity of all the influencing factors turned out to be the surrounding rock stress. This indicates that special attention should be paid to the influence of in-situ stress of the surrounding rock when designing the deep high-stress roadways. Therefore, the effective release of the surrounding rock stress can be achieved by using the high strength, high elongation anchor cable and adding the yieldable device. Meanwhile, the integrity of the surrounding rock can be improved by applying high pre-tightening force and grouting reinforcement, resulting in better control performance of surrounding rock.

Key words: deep large section, mining roadways, Hoek-Brown criterion, the upper bound theorem, roof, anchor cable design