Development of a precast concrete lining technique using prestressed concrete structures

摘要

The Prestressed & Precast Concrete Segmental Lining (P&PCSL) is used for shield tunnels. Its primary feature is that it integrates segments into one ring by introducing prestress in the tunnel circumferential and longitudinal directions. Introducing prestress enables the elimination of joint metals and reduces the volume of reinforcement, thus reducing the manufacturing cost of precast concrete segments. It also enables quality improvement and labour saving in assembly and provides greater adaptability for tunnels with large apertures, where deformation due to self-weight is a problem. The P&PCSL has been implemented in 3 times construction projects after undergoing various performance tests and workability verification tests.