Tubbing-type tunnel lining

摘要

A tubbing-type tunnel lining, which comprises a plurality of tubbing rings, each of which consists of an even number of tubbing blocks, which are similar or identical and have a trapezium-shaped or trapezoidal or diamond basic shape and are so arranged that the joints between adjacent rings are defined by the end faces of said blocks and are connected together by plug-connections, which permit a restricted transmission of shear forces, and in each ring are connected at inclined longitudinal gaps by key-groove connections consisting of continuous longitudinal grooves in inclined longitudinal side faces and keys inserted therein. The blocks themselves have zones which are compressible in the peripheral direction of the tubbing ring and/or said keys are compressible and in a relaxed state of said ring keep the blocks thereof psaced apart so as to define said longitudinal gaps whereas the rings are compressible under the load imposed by the rock so as to reduce the diameter of said ring and the width of said gaps. To ensure a proper guidance of the blocks as the diameter of the tubbing ring is decreased, each tubbing block is connected at each end face by at least two plugs to at least one tubbing block of an adjacent tubbing ring, only one of said two plugs is retained by a locating bearing in the block whereas at least one additional one of said plugs extends in one of the blocks which are connected by said plug in a slot and in response to a decrease of the diameter of the tubbing ring is capable of a limited displacement in said slot.