Failure of PC Wire for PCC PIPES due to Corrosion in Man-made River Project Investigation of Possible Causes and Relation of Wire Breaks with Potential Measurement

Pre-stressed wire is considered the most important in manufacturing pre-stressed concrete pipes, this is because the life of the mentioned pipes depends on the integrity of the wire. When the wire wrapped around the concrete core, it provides a compressive strength which enable the concrete cores to withstand the internal and external pressures. Since LIBYA has constructed different stages of man- made river project using the pre- stressed concrete pipes, in different diameters (1.6, 2.2, 3.6 and 4.0 m) to transport water from the south part of the country to the north populated area, pipe failures due to corrosion have been occurred after several years of operation at different locations of pipeline route. The PC wire corroded and at the end breaks and become unable to withstand internal water pressure. The wire breaks recorded using hydro phone technique added extra pressures on the project management staff and engineers, to resolve and study the possible main cause of wire break and pipe failure. Information regarding the PC wire used will be provided in this paper which include specification, manufacturing etc. In this paper, causes of wire corrosion and wire breaks after several years of PCCP operation will be discussed and explained, in addition to that, correlation between wire breaks and pipe potential will be addressed and highlighted.