Abstract To research the reinforcement effect of bonding steel to the damaged linings of tunnels under lateral loads, a 1∶10 model test was conducted, and the modes of deformation and damage of the tunnel lining structure under lateral loads and the steel-bonded structure in different states of damage were researched. The test results showed that under lateral loads, the damage mode of the tunnel lining structure was brittle failure, and the damage development process was as follows: arch waist cracking — brittle shear failure of arch shoulder — damage to arch waist ductility and bending; damage was concentrated on the crown of the lining structure and the side wall-waist on the left and right sides, and the section stiffness was rapidly attenuated, which was the vulnerability and dangerous point of the structure; after steel was bonded for reinforcement, the stripping of bonded steel caused by the shear stress of the bonding surface at the structure waist was the major factor causing the instability of the reinforced structure; when the remaining bearing capacity proprtion was 30%, the bearing capacity of the structure reinforced by bonded steel was not increased; when the remaining bearing capacity proprtion was 48%, the bearing capacity of the reinforced structure was increased by 4.1%; when the remaining bearing capacity proprtion was 60%, the bearing capacity of the reinforced structure was increased by 10.2%. Consequently, after the damaged tunnel lining was rein? forced with bonded steel under the lateral pressure, the bearing capacity was not significantly improved and the reinforcement effect was limited, and the lining damage caused by lateral loads should not be reinforced by bonding steel.
Abstract：
To research the reinforcement effect of bonding steel to the damaged linings of tunnels under lateral loads, a 1∶10 model test was conducted, and the modes of deformation and damage of the tunnel lining structure under lateral loads and the steel-bonded structure in different states of damage were researched. The test results showed that under lateral loads, the damage mode of the tunnel lining structure was brittle failure, and the damage development process was as follows: arch waist cracking — brittle shear failure of arch shoulder — damage to arch waist ductility and bending; damage was concentrated on the crown of the lining structure and the side wall-waist on the left and right sides, and the section stiffness was rapidly attenuated, which was the vulnerability and dangerous point of the structure; after steel was bonded for reinforcement, the stripping of bonded steel caused by the shear stress of the bonding surface at the structure waist was the major factor causing the instability of the reinforced structure; when the remaining bearing capacity proprtion was 30%, the bearing capacity of the structure reinforced by bonded steel was not increased; when the remaining bearing capacity proprtion was 48%, the bearing capacity of the reinforced structure was increased by 4.1%; when the remaining bearing capacity proprtion was 60%, the bearing capacity of the reinforced structure was increased by 10.2%. Consequently, after the damaged tunnel lining was rein? forced with bonded steel under the lateral pressure, the bearing capacity was not significantly improved and the reinforcement effect was limited, and the lining damage caused by lateral loads should not be reinforced by bonding steel.
LIU Xuezeng1 GU Wenchuan1 YANG Zhilu2,
3 GUO Qiaokun4 HE Guohua5 FENG Jin6
.Test Study on the Reinforcement Effect of Bonding Steel to Damaged Tunnels under the Lateral Loads[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(4): 187-195
2022, Vol. 59 