Shanghai metro extension is one of the most enormous TBM tunnel investigation nowadays in Republic of China. Because of the size of the investment several research connected to the project. The Customers tried to use the most economic concrete reinforcement, and joint element between the rings. The Tongji University made a real scale test about the full precast concrete tunnel ring. The test was verified with numerical models. After the clarification of the material parameters, finite element analysis was done to optimize the steel bar reinforcement in the ring, and replace it with synthetic fibres. To find the optimum joint formation different models were carried out. The effect of the different bolt types (curved or straight) was significant, just like the use of fibres. With the optimum solution the structure will be more ductile than with the original formation.
#CCC #tunnel #TBM #Shanghai
