2018 Volume 67 Issue 5 Pages 216-221
The number of photovoltaic system has increased drastically due mainly to a profitable selling price of electricity for owners set by feed-in tariff. Metal piles are currently used as typical foundation of the system from the viewpoint of high workability and low cost. However, there is a problem that the corrosion rate of metal foundation pile at ground level is faster than that of other part of the pile. In this paper, soil corrosion at shallow layer was investigated by exposure test in soil, chemical analysis of soil and electrochemical analysis. The corrosion rate of metal pile in shallow soil layer was higher than 0.02 mm/year which is commonly recognized as the corrosion rate of metal in soil. The corrosion rate in shallow soil layer mostly increased with decreasing the polarization resistance measured in soil environment. Those investigated results showed that the macro cell corrosion at ground level is thought to be attributed to change of chemical composition caused by land creation and dispersion of manure.
