Long submerged tunnel inspections: the Mantaro headrace tunnel,Central Andes Mountains, Peru

摘要

Located in the central Andes mountains in Peru, the 900 megawattC.H. Antunez de Mayolo hydroelectric facility (Mantaro) generatesapproximately 70% of the region's power, which includes the capital cityof Lima (population 7 million). In a remote region approximately 350kilometres east of Lima, at an altitude of over 2500 meters above sealevel, the Mantaro facility (named after the river upon which it issituated) is a major engineering feat in itself. The headrace tunnelservicing the plant, 4.8 metres (15 feet) in diameter, has been boredthrough the Andes mountains and extends for an extraordinary distance of19.8 kilometres (66000 linear feet). Since its construction in the early1970s this facility has been unable to meet its maximum generatingcapacity due to a gradual loss of head pressure. The purpose of theinspection is to determine the cause of this problem and to identifypossible solutions. The paper describes the ROV developed to carry outthe inspection. The ROV incorporates an application designed sensorpackage, multiple camera suite, dual sonar, NDT probe, five functionmanipulator and a concrete coring drill