Feasibility Study on Non-contact Measurement Method for Primary Support of Tunnel

Inspired by studies of tunnel monitoring by the three-dimensional laser scanning, this paper aims to explore the synchronization of primary support deformation and surrounding rock deformation and the feasibility of non-contact measurement method for primary support of tunnel. The deformations of tunnel under external conditions such as full-face excavation, three-bench excavation, initial defects, shallow buried, and bias were simulated in ANSYS. The maximum entropy theory was used in the simulation results, and the primary support deformation and surrounding rock deformation of the tunnel were analyzed by the probability density function. The results showed that the primary support deformation and surrounding rock deformation was synchronized in most conditions, which proved the feasibility of non-contact measurement method for primary support of tunnel. However, the vault void had a great influence on the deformation curve of upper bench excavation. It was suggested that the field test should be carried out to verify whether the traditional monitoring results are consistent with the three-dimensional laser scanning results in this condition.