Abstract With a maximum horizontal geostress of 27.16 MPa and a rock strength-stress ratio of 0.49, the Muzhail?
ing tunnel at the ridge section of the Lanzhou-Chongqing Railway is under extremely high geostress. Focused on the problems of initial support deformation and secondary lining cracking during the construction of the Muzhailing tunnel, this paper analyzes the deformation and mechanical characteristics of the surrounding rock-lining structure by actual measurements and numerical simulation. Specifically, it addresses the effects of a stress relaxation zone by comparing changes to the lining′s stress concentration factors regarding a surrounding rock-lining structure with or without stress relaxation zones; examines the effects of the elasticity modulus Er on the stress relaxation zone, thickness La of the stress relaxation zone, lateral pressure coefficient and tunnel sectional form on the stress distribution of the surrounding rock-lining structure; and analyzes the causes of lining cracking for the Muzhailing tunnel at the ridge section.
Abstract：
With a maximum horizontal geostress of 27.16 MPa and a rock strength-stress ratio of 0.49, the Muzhail?
ing tunnel at the ridge section of the Lanzhou-Chongqing Railway is under extremely high geostress. Focused on the problems of initial support deformation and secondary lining cracking during the construction of the Muzhailing tunnel, this paper analyzes the deformation and mechanical characteristics of the surrounding rock-lining structure by actual measurements and numerical simulation. Specifically, it addresses the effects of a stress relaxation zone by comparing changes to the lining′s stress concentration factors regarding a surrounding rock-lining structure with or without stress relaxation zones; examines the effects of the elasticity modulus Er on the stress relaxation zone, thickness La of the stress relaxation zone, lateral pressure coefficient and tunnel sectional form on the stress distribution of the surrounding rock-lining structure; and analyzes the causes of lining cracking for the Muzhailing tunnel at the ridge section.
HUANG Ming-Li- 1 Zhao-Jian-Ming- 1 Tan-Zhong-Sheng- 1 Li-Yan-Zong- 2
.Analysis of the Deformation and Mechanical Characteristics of the Surrounding Rock-Lining Structure of the Muzhailing Tunnel[J] MODERN TUNNELLING TECHNOLOGY, 2016,V53(6): 89-99
2016, Vol. 53 