Quantification of the amount and the corrosive action of stray current (from the LRT) entering the DLSU water mainlines

• Main Authors: Monroy, Teddy Go, Wong, Kam tai
• Format: text
• Language: English
• Published: Animo Repository 1992
• Subjects: Stray currents > Philippines > Manila; Underground pipelines > Corrosion; Chemical Engineering
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/3968
• Institution: De La Salle University

Buried metal structures are subjected to different kinds of corrosion one of which is due to stray currents. With the erection of the metro rail system in 1985, it became inevitable that underground pipelines will be affected by stray currents leaking from the LRT system. Since stray currents cause a very fast deterioration of underground metalworks as compared to other types of corrosion, it is therefore, imperative that a quantitative study be made on the effects of this type of corrosion.Because of their apparent orientation, that is, positioned very near the LRT, De La Salle water pipelines are most likely to be affected by stray currents. This study concerns in the determination if currents do indeed enter a pre-selected test pipe, whether they are stray currents from the LRT, and how extensive is the corrosion these currents bring about.Soil resistivity was measured as well as the pipe resistivity. Pipe potentials were determined by the employ of a copper-copper sulfate half cell. Soil moisture and pH were also determined. Finally, quantification of the amount of corrosion was done by using sample pipes that acted as sacrificial anodes.