CUT AND COVER CONSTRUCTION ON UNSTABLE SLOPES

The construction of buried structures by the cut and cover method provides an alternative to deep cuts and large retaining walls for highway construction on unstable slopes. Two cases of cut and cover construction for a highway project in northwestern Greece are presented. In both cases the slope instability was to a blue-grey marly clay layer which exhibited strain softening characteristics and lost much of its strenth when wet. After a detailed investigation of the soil properties and study of alternative designs, the solution of buried concrete structures was approved. Details of the design and construction are presented. The buried structures act as earth reinforcing elements, increasing the stability of the slopes while costing approximately the same as other alternatives and without damaging the environment.