Digitizing and modeling of structural planes in fractured rock mass tunnel based on SfM

SfM method has been deployed to investigate structural planes of rock mass in tunnel to meet the need of rapid and digital construction. 3D surface model of tunnel rock mass has been reconstructed rapidly, effectively, and accurately. And then the characteristic parameters of structural planes are obtained. Based on this method, probabilistic model of the dip, dip angle, trace length, and spacing of structural planes has been determined and significance test of F value is carried out. A 3D stochastic network model of structural plane with Baecher disk model is established based on Monte Carlo method. Through sectioning of the structural plane network model, the two-dimensional profile of trace distribution has been generated and compared with that of actual excavated structural plane. The maximum difference ratio is 19.1%, which shows that this method can identify the structural plane and obtain the characteristic parameter accurately and rapidly. The results show that the stochastic network model of structural planes generated is highly reliable.