As roads congestion worsens, tunnels have become an important project in the construction of urban roads. The tunnel rock bolt is mainly used for the initial support of the tunnel, and the high-pressure grouting is realized through the hollow injection bolts to strengthen the soil or rock mass so as to ensure the surface stability. According to the type of support in the tunnel, it can be divided into advance support and radial support. Protection, face support, locking foot support and door reinforcement. Self drilling hollow anchor bolt is one of the most commonly used tunnel rock bolts. It integrates drilling, grouting and anchoring, and it has the advantages of simple and quick construction and good anchorage effect. It can be applied to a variety of complex geological conditions to anchor the rock mass. The construction in the city generally has a greater impact on the citizens and brings great inconvenience to people's lives. Self drilling rock bolting can be installed with a small robotic arm, small work area, low noise, and almost no impact on the surrounding buildings. It is the most commonly used anchoring support tool in urban construction.
