ABSTRACT
In this paper, shield tunnel was regarded as an elasto-plastic uniform beam placed on an elastic foundation in longitudinal direction. Firstly with the help of this equivalent uniform beam model, the authors deduced the formula to calculate equivalent extension, compression and bending stiffness of shield tunnel structure, and the maximum extensive and compressive stress in bolts and linings. Then we analyzed stress distribution in tunnel structure and extension of joint induced by uneven settlement along the tunnel. At the end of this paper, based on a case study of Shanghai No.2 Metro, the extension of the joint was calculated. The calculated result is well consistent with that of measured data, which verified the suitability of theoretical method proposed above for shield tunnel.
