# Deep Soft Rock Tunnel Perimeter Rock Control Technology and Research
## 1 Introduction  
As the most important energy source in China, coal is mainly mined by open-pit mining and shaft mining. Shaft mining has always been the most important mining method in China, and the biggest problem faced by this mining method is how to effectively control the roadway rock. In recent years, China's roadway perimeter rock has mainly used a combination of anchor rods, anchor cables, and steel supports. In most cases, these support methods can be economical and effective in maintaining the stability of the roadway perimeter rock [1, 2, 3, 4, 5, 6]. As the main structure of the anchor network support, the anchor can maximize the self-supporting ability of the surrounding rock and actively reinforce the surrounding rock, while the timing of anchor application is the most important factor affecting anchor support. In the actual project, the anchor system not only has to withstand the pressure of the original rock, but it is also subject to the influence of the mining pressure, which means that the designed support structure must be able to withstand the original rock stress and mining pressure, so as to achieve the expected support effect. However, as the mining conditions become more and more complex, such as with weak and fragile peripheral rock, peripheral rock stress increases, i.e., if you do not adjust the original support, it will lead to the support structure becoming damaged, or even failing. Thisrequires a specific analysis of the specific surrounding rock conditions to avoid situations where the anchor force is excessive is some places while being insufficient in others [7; 8; 9].  
In order to reduce operating costs and to ensure safe production at the same time, the roadway support program also needs to be more economical and reasonable, improve support efficiency, and reduce support costs. Coal mine roadway excavation and support is a complex process of dynamic change, generally following the \"gravitational field disturbance--support--stress field balance\" model. With such a law of change, the corresponding roadway support parameters need to be adjusted according to the specific circumstances to ensure that the stress balance of the surrounding rock deformation can be controlled to ensure effective support [10; 11; 12; 13].  
With the gradual depletion of shallow coal resources, mining operations must be continuously developed in deeper locations. As such, the roadway will be in an environment of high geostress long-term action, and the traditional support structure will not meet the needs of safe production due to higher requirements for the support structure. The deep rock layer is characterized by a complex geological structure, high ground stress and rock fissure development, etc. Reasonable and effective control technology of deep tunnel perimeter rock can ensure safe production on the one hand and reduce the operation cost of the tunnel on the other hand, while increasing the digging efficiency at the same time. Under the influence of different geological conditions, seeking a more reasonable roadway support program is of great significance to the safe production of coal mines [14; 15; 16; 17; 18; 19]. Therefore, this paper takes the 2500 transportation roadway of a mine as the engineering background and puts forward the concept of \"stress-balanced\" support, which reduces the support cost and improves the comprehensive benefit on the basis of effective control of roadway perimeter rock.