Experiment study on reinforcement of PCCP inside with circumferential pre-stressed carbon fiber plate

In order to repair the damaged prestressed concrete cylinder pipe (PCCP) which is hard to be excavated timely and effectively, so as to reduce or even avoid PCCP burst, the reinforcement technology of circumferential pre-stressed carbon fiber plate in PCCP was proposed. This technology pre-stresses the carbon fiber plate inside the pipe, and sticks it to the inner wall of PCCP with high-performance structural adhesive. PCCP is strengthened with a higher bearing capacity. A test of concrete inner ring combined with outer ring was designed to verify the feasibility of the reinforcement method and optimize the construction technology. The test showed that the pre-tensioned CFRP was successfully bonded to the outer concrete ring. After roughening and base treatment of the surface of concrete, the system formed by concrete, adhesive and pre-stressed carbon fiber plate was reliable, and could provide a bond strength of no less than 0.8 MPa. The test result indicates the foundation test scheme and reinforcement scheme are feasible. A further test scheme to strengthen PCCP is put forward with end-to-end carbon fiber plate.