In-situ test experimental research on leakage of large diameter pre-stressed concrete cylinder pipe (PCCP)

lines have been applied to the Mid-route of the South-to-North Water Transfer Project. However,
the leakage problem of PCCP causes annually heavy economic losses to our country. In such a
context of situation, how to detect leaks rapidly and precisely after pipes appear cracks in water
supply system has great significance. Based on the study and analysis of the characteristic
structure of large diameter PCCP, a new leak detection system using fiber Bragg grating sensors,
which can capture signals of water pressure change, is proposed. The feasibility, reliability and
practicability of the system could be acceptable according to data achieved from in–situ tests.
Moreover, the leak detection system can monitor in real-time of dynamic change of water pressure. The equations of the leakage quantity and water pressure have been presented in this paper, which can provide technical guidelines for large diameter PCCP lines maintenance.