Study on Calculations and Influence Factors of Bending Stiffness of Segment Ring Joints of Shield Tunnels
（1 State Key Laboratory of Rail Transit Engineering Informatization, China Railway First Survey and Design Institute Group Co., Ltd.,Xi′an 710043；2 Shanxi Railway and Underground Traffic Engineering Key Laboratory, Xi′an 710043）
Abstract：
In order to obtain a calculation method for bending stiffness of the shield tunnel segment ring joint in
longitudinal beam-spring model, the analytic method is adopted to deduce calculation formulas for bending stiffness of segment ring joint under simple bending and stretch bending conditions based on Shiba model, and a quantitative analysis is conducted on the sensitivity and the influence way of each influencing factor. The results show that the influencing factors of bending stiffness of segment ring joint are mainly the segment ring width, section size, ring bolt parameters and axial tensile force and so on, and the sequence of influence on bending stiffness of ring joint are section size, ring bolt parameter and width of segment ring in descending order; the way of influence of axial tensile force on bending stiffness of ring joint is different than that of above mentioned factors, under action of the axial tensile force the bending stiffness of ring joint presents obvious non-linearity characteristics, the relationship of bend?
ing stiffness of ring joint, longitudinal bending moment and longitudinal axial force is of“step-shape”curved surface in 3D space, and the values of stiffness are maintained between two specific levels of upper bench and lower bench; when the surface of ring joint is fully opened under the effect of stretch bending, the bending stiffness of ring joint is reduced by around 40% compared with that of partially opened.
ZHANG Jing1,
2
.Study on Calculations and Influence Factors of Bending Stiffness of Segment Ring Joints of Shield Tunnels[J] MODERN TUNNELLING TECHNOLOGY, 2020,V57(4): 104-112
2020, Vol. 57 