Model test and discrete element method simulation of tunnel face stability in sand-gravel inclined layered stratum

• Published in: Computers and geotechnics Vol. 172; p. 106456
• Main Authors: Tu, Shiqin, Li, Wei, Zhang, Chengping, Liu, Tongxin, Wang, Libin, Jin, Zixian
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2024
• Subjects: Discrete element method; Inclined layered stratum; Model test; Tunnel face; Inclined layered stratum; Tunnel face; Model test; Discrete element method
• ISSN: 0266-352X; 1873-7633
• DOI: 10.1016/j.compgeo.2024.106456

The inclined layered stratum is often encountered in the geological and geotechnical engineering. The stability of the tunnel face in inclined layered stratum plays an important role for the design and construction of the tunnels, which has been neglected in previous researches. In order to investigate the failure response of the tunnel face in sand-gravel inclined layered stratum, a series of three-dimensional (3D) model tests with different occurrence of the inclined stratum are carried out. The 3D discrete-element method (DEM) is also employed to simulate the failure process of the tunnel face in inclined layered stratum with the same condition. The comparisons of results obtained by DEM simulation, model test and limit analysis are discussed to validate the accuracy of this study. The critical support pressure of tunnel face decreases with the increase of inclined angle of soil interface. Based on the stress redistribution monitored in model test, the area of soil arch in front of tunnel face in horizontal layered stratum is narrower than that in inclined layered stratum. The influence of the inclined layered stratum on the stability of tunnel face presented in this study provides useful guideline for practical construction and design of tunnels.