When the metal coating is punctured or scratched, the capsules in the damaged area burst and ooze restorative liquids, in the form of compounds called trivalent chromates.

However, when we calculate the area under this curve, we see that the short burst approach accomplished: 38 units of work!

Due to high in situ stress in the powerhouse area, important deformation of local surrounding rock, rock burst, shotcrete spalling occur during excavation.