Research on Deformation Characteristic of Shield Tunnel Segment Crossing Karst Cave
Based on the theory of elliptical eccentricity,the deformation characteristics of shield tunnel segments crossing karst caves are studied by numerical calculation analysis method.The main conclusions are as follows:(1)When the shield tunnel crosses the karst area from above and below,the larger the diameter of the central karst cave,the smaller the eccentricity of the ellipse after the shield segment deformation,and the shape of the ellipse tends to be more circular;with the increase of the distance between the karst cave and the tunnel,the eccentricity of the ellipse after the shield segment deformation is larger,and the shape of the ellipse is flatter.(2)When the shield tunnel crosses the karst area from the side,at an angle of obliquely upward 45° and obliquely downward 45°,the central karst cave will increase the tunnel deformation,the larger the diameter of the central karst cave,the greater the deformation of the shield tunnel segment,the greater the eccentricity of the ellipse after the shield segment deformation,and the flatter the shape of the ellipse.
shield tunnel segmentkarst cavedeformation characteristicnumerical calculation analysis methodnumerical model