Use of soft rockfill at Evretou Dam, Cyprus

This paper describes the properties of this soft rockfill, together with the effect of these properties on the embankment design. The breakdown that occurs on handling, resulting in a composition of 25-40 percent sand sized material (0.075-2 mm) and up to 25 percent silt sized rock flour (less than 0.075 mm), means that the engineering properties of permeability and shear strength are intermediate between those of an earthfill and a hard rockfill. Instrumented performance of the rockfill is described, together with the interaction of the core and the rockfill shoulders. The embankment is founded on up to 40m of alluvial deposits comprising interbedded silty sands and sandy gravels with many cobbles. The properties of this foundation are described where they affect the external rockfill slope.