Issues of Enguri Arch Dam Bottom Outlet Structure

Abstract

Enguri HPP high-pressure outlet is equipped with service and maintenance gates, which are installed in cantilever part of the arch dam (downstream). With the view of ensuring the protection of the chamber casing from the velocity ow inuence (cavity resistance) and reduces the dynamic loads on the arch dam the maintenance gates designed with accompanying ring. During operation bottom outlet, due to disruption of water tightness of maintenance gate chamber casing and leakage developed in the concrete, the steel plate of the casing of service gate chamber was disconnected from the reinforced concrete diaphragm and was deformed in direction of the gate. This hampered the gate operation, also caused the redistribution of loads and worsened the strength conditions of the cantilever. This report includes some results of dam cantilever strength analysis during operation (chambers service gates water tightness loss).