The Roselend Dam

Abstract

This dam is located on the higher reaches of the river Doron of Beaufort, in the Alps, close to the Mont Blanc massif. The reservoir has a capacity of 187 cubic hectometres. The water is taken along an underground conduit, 13 kms in length, to the power station, which has 500.000 kW capacity. It utilises a hydrostatic head of 1208 ms, and water flow of 50 m³/sec. The total yearly output will ultimately be of the order of 1000 10⁶ kWh. This energy is obtained from a basin of 272 kms². This project involved the construction of a 150 ms high dam. After considering the various alternatives of a gravity, vault, abutment or multiple vault dam, it was finally decided to build a dam consisting of a central, self supporting part, extending on each side with the support of abutments. The design was developed with the aid of reduced scale gypsum models, which were progressively corrected until the final solution was established. The upstream side dam has vertical sides. The abutments have a slope of 0.75, and a maximum thickness of 7.5 ms. The vaulted part of the dam has a maximum slope of 1.05, and its thickness at the midpoint of the base is 22 ms. The total length of the dam is 820 ms, its maximum, height is 150 ms, and the volume of concrete employed is 940.000 ms³