Rehabilitation of rail guides on diffuser gate of power plant "Peruča"
Hydroelectric power plant "Peruča" was built in 1960. The plant has an installed flow of 2x60 m/s and installed power Ni = 2x20.8 = 41.6 MW. During the Serbian aggression on Croatia, HEPP "Peruča" was occupied by rebel paramilitaries. On 28.01.1993, while withdrawing, they blew up the dam with the intention to destroy the HEPP "Peruća" and downstream settlements. Due to the age of buildings, unfavourable conditions of exploitation, as well as the consequence of the war, the structures of HEPP "Peruča" were damaged. The dam and the facilities that were damaged by blasting the dam were repaired immediately after the liberation of the plant. Electro mechanical, hydro mechanical equipment and related structures were replaced and refurbished in the process of revitalization of HEPP "Peruča". An inspection of turbine diffusers showed damaged concrete by rails guides on the diffuser gate, due to which significant penetration of water into the diffuser area occurred. In order to ensure operational readiness of the facility and safety at work, it was necessary to repair this damage. Due to long-time operation and age there was damage on the surface of parts of the construction at the junction of the drainage channel and diffuser, above and under water. Therefore, within the scope of rehabilitation works on rail guides, these surfaces and the part of the facade damaged by war activities had to be repaired.
Rehabilitation of rail guides on the diffuser gate and parts of the construction at the junction of the diffuser and drain channel can be performed successfully and reliably only in conditions without the presence of water and therefore a prefabricated cofferdam was made so that rehabilitation works could be done in dry conditions.