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Abstract Based on the background of Xi¢an metro shield tunnel engineering and the geological environment of Xi¢an ground fissure，the physical modeling of segment lining structure experiment of shield tunnel crossing the ground fissure with 60° is designed according to similarity theory. The strains of segment concrete of longitudinal bolt and circumferential bolt，the contact soil pressure and peripheral soil pressure，the convergence displacement of segment lining，the soil settlement on the top of model and other macrophenomena all show that the main deformation and damage of segment lining structures of shield tunnel crossing the ground fissure with 60° are of shearing with local distortion and bending. The deformation and damage range are from 0.75D(D is the external diameter of segment ring) in the hanging side to 0.50D in the lying side. The distribution of concrete crack is near the bolt hole；and the deformation of longitudinal bolt near ground fissure is of shearing first with distortion and tension. The deformation and damage of segment ring are asymmetric and partial compression；and the dislocation of circumferential seam on the crown which is up to 30 mm(0.025D) is bigger than those of soffit and arch waist. It is difficult for the segment lining to undergo the deformation 20 cm(0.166 7D) of ground fissure；and the segment lining structure of shield tunnel is unsuitable for the geological environment with violent activity of ground fissure.
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Received: 12 June 2009
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