Corrosion of steel H piles in decomposed granite

To study the corrosion of steel H piles in a completely decomposed granite, piles were exposed by excavation 22 years after their installation. The th ickness of the pile sections was measured. The average corrosion rate of th e steel piles was estimated to be 0.011 mm/year, and the maximum corrosion rate was estimated to be 0.015-0.018 mm/year. The rates are low. The result s confirm the conclusions derived from tests done in places with temperate climate that steel piles installed in undisturbed, native soils undergo lit tle corrosion. Thus, such conclusions are also applicable to the completely decomposed granite in a place like Singapore with high year-round temperat ures ranging from 25 to 35 degrees C.