An Improved Longitudinal Structure Model of Cross-River Shield Tunnel and Its Application
ZHOU Ning
YUAN Yong
Abstract：The equivalent-continuous rigidity model was modified by the introduction of circular seam coefficients for a shield tunnel.The basic assumptions and the formula for the model are given.A relationship between circular-seam deformation and circular-seam equivalent rigidity is developed.Cross-river shield tunnels in Shanghai area were analyzed with the model.Critical deformation values of the shield tunnel were used to build a relationship between longitudinal deformation and circular-seam stretching of the shield tunnel.It is shown that critical curvature radius values of the cross-river shield are smaller than for metro-shield tunnels.A longitudinal d5eformation radius less than 1.257 kilometers in the cross-river tunnel results in circular-seam stretching of more than 6 mm.Water sealing of the tunnel is not effective and serious leakage may appear with this amount of stretching.If the bolt stresses of the tunnel are limited the circular-seam stretching is 21.00 mm and the connections may be destroyed.The safety requirements of the shield tunnel are not satisfied under these condition.
Keywords：cross-river tunnellongitudinal deformationmodel modificationcircular seam stretching-amountcurvature radius
Publication Date：2010-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 208-213 )