Railway tunnel lining for subsidence areas - bearer rings with rim bulge locked watertightly together

摘要

Lining for fully enclosed railway tunnels in areas exposed to the effects of mining subsidence consists of corrugated bearer rings which are connected water tightly to one another lengthways along the tunnel so as to allow longitudinal deformation only within limits imposed by orthotropic yield and resistance principles. Each ring is fitted with an expansion member in the form of a bulged area projecting beyond the section of the ring. In the bulge vicinity each ring should curve more steeply than the circumference of the tunnel section, and this area should go over into the circumference through a region of opposed curvature.