The behaviour of a very high CFRD under first reservoir filling

At 188 m, El Cajon is the highest concrete faced rockfill dam (CFRD) in Mexico and one of the highest in the world. Its behaviour during construction and under reservoir loading is presented here. The dam monitoring and performance after first filling are described, together with the instrumentation system installed, in an attempt to understand the deformations characteristics of compacted rockfill, to predict displacements of the concrete face, and to provide a better understanding of leakage and face cracking incidents recorded at recent high CFRDs.