TY - JOUR
T1 - Thermo-mechanical analysis of fire effects on the structural performance of shield tunnels
AU - Shen, Yi
AU - Zhu, Hehua
AU - Yan, Zhiguo
AU - Zhou, L.
AU - Zhang, T.
AU - Men, Y.
AU - Lu, Yong
N1 - Funding Information:
The authors wish to acknowledge the sponsorship from Shanghai Sailing Program ( 20YF1451400 ), the Natural Science Foundation of China (Grant No. 52208401) and the Research Fund of State Key Laboratory for Disaster Reduction in Civil Engineering .
Publisher Copyright:
© 2022
PY - 2023/2
Y1 - 2023/2
N2 - Investigating fire effects is a continuing endeavour in the research and practice communities concerned with the design and safety of shield tunnels. This paper aims to provide a comprehensive model for the assessment of structural safety of a shield tunnel segmental ring exposed to fire. A thermo-mechanical model for assembled shield tunnel structure in fire is developed to provide a basis for a holistic analysis by incorporating tunnel lining segments and longitudinal joints, as well as improved predictions for the temperature, stress and deformation distributions in the tunnel structure. Validation of the numerical results against experimental data shows satisfactory agreement. Parametric studies are subsequently conducted to investigate the effects of spalling, buried depth and cooling-off phases on the fire behaviour of the shield tunnel. The results show that the damage and failure of a tunnel lining structure under high temperature are mainly due to the combined action of internal thermal expansion force and thermal stress. Spalling leads to the loss of a key “insulation” layer of a tunnel lining structure. On the other hand, the constraint of strata on the tunnel structure under high temperature not only restrains the deformation of key parts of the structure, but also helps offset the adverse effect of load on the structure through elastic resistance.
AB - Investigating fire effects is a continuing endeavour in the research and practice communities concerned with the design and safety of shield tunnels. This paper aims to provide a comprehensive model for the assessment of structural safety of a shield tunnel segmental ring exposed to fire. A thermo-mechanical model for assembled shield tunnel structure in fire is developed to provide a basis for a holistic analysis by incorporating tunnel lining segments and longitudinal joints, as well as improved predictions for the temperature, stress and deformation distributions in the tunnel structure. Validation of the numerical results against experimental data shows satisfactory agreement. Parametric studies are subsequently conducted to investigate the effects of spalling, buried depth and cooling-off phases on the fire behaviour of the shield tunnel. The results show that the damage and failure of a tunnel lining structure under high temperature are mainly due to the combined action of internal thermal expansion force and thermal stress. Spalling leads to the loss of a key “insulation” layer of a tunnel lining structure. On the other hand, the constraint of strata on the tunnel structure under high temperature not only restrains the deformation of key parts of the structure, but also helps offset the adverse effect of load on the structure through elastic resistance.
U2 - 10.1016/j.tust.2022.104885
DO - 10.1016/j.tust.2022.104885
M3 - Article
SN - 0886-7798
VL - 132
SP - 1
EP - 13
JO - Tunnelling and Underground Space Technology
JF - Tunnelling and Underground Space Technology
M1 - 104885
ER -