Experimental Investigation of the Deformed Stagger-Jointed Segmental Tunnel Linings Strengthened by Epoxy-Bonded Filament Wound Profiles

A new type of Filament Wound Profiles (FWPs) have been applied to strengthen the deformed stagger-jointed segmental tunnel linings, and a full-scale test was carried out on the ultimate bearing capacity of the linings that are strengthened by the new FWPs. The failure phenomena and the main experimental results were obtained, including the load-displacement curve, strain and bond failure. The internal forces of the FWPs in the strengthened lining were calculated and discussed. The failure chain and weak sections of the strengthened lining were discussed. The overall strengthening benefits were summarized. The results show that: (1) The FWPs were in the state of compression bending or tension bending, and bore part of the axial force and bending moment in the strengthened lining. (2) The initial failure of the strengthened linings was caused by the bond failure between the FWPs and the concrete linings at 0°. (3) The filament wound profiles strengthening method can effectively improve the ultimate bearing capacity and stiffness of the stagger-jointed shield tunnel linings.