Parameters for Pipe Roof Support of Shallow Bored Tunnels

Based on the pipe roof advance support of a certain shallow bored tunnel, the application theory of pipe roof parameters is analyzed. Using a stiffness reduction model, the pipe roof layer is converted into an isotropic reinforcement body, a numerical simulation is conducted for the effects of single-and double-layer pipe roof advance reinforcement, and a comparison with monitoring data is carried out. An analysis of the reinforcement effects of a pipe roof with different diameters is undertaken. The results show that the internal force of the initial support and temporary support decrease with an increase of the pipe roof diameter, and surface settlement therefore decreases.