Time-dependent Reliability Analysis of Shield Tunnel Structure under Corrosion Conditions of Segment Rebars and Bolts
1 Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education, Tongji University, Shanghai 200092;2 Department of Geotechnical Engineering College of Civil Engineering, Tongji University, Shanghai 200092)
Abstract：
As for the uncertainty of the influence of corrosion of segment rebars and joint bolts on the structural be? haviors of shield tunnels, the uncertainty relationship between the material corrosion depth and the time is established by using a Gamma random process model on the basis of the measured corrosion data. In the ABAQUS software, the calculation process of tunnel structure reliability is established by using Python language to analyze the structural reliability of shield tunnels under different corrosion conditions of rebars and bolts, and the time-dependent variation laws of failure probability of tunnel structure are obtained under ultimate limit state and serviceability limit state. The study results show that once the rebars and bolts are rusted, the failure probability of the tunnel structure would reach a higher level under the common corrosion rate of 20%~30% in the whole life cycle of the tunnel, of which more than 30% bolt corrosion rate might make the failure probability of the bearing capacity on the joint section close to 100%. The failure probability of a lining ring of the tunnel structure is significantly affected by bolt corrosion, and rebar corrosion might also have a great impact on the bearing capacity and stiffness of segments.
ZHANG Dongmei1,
2 CHEN Congcen2
.Time-dependent Reliability Analysis of Shield Tunnel Structure under Corrosion Conditions of Segment Rebars and Bolts[J] MODERN TUNNELLING TECHNOLOGY, 2021,V58(6): 111-120
2021, Vol. 58 