Design and construction of Revelstoke earthfill dam

Abstract

The Revelstoke earthfill dam, located on the Columbia River in Central British Columbia, consists of a central till core with upstream and downstream granular shells. A core trench up to 76 m (250 ft) deep had to be excavated through the overburden in order to found the core on rock and approximately 7.6 × 106 m3(10 × 106 yd3)of overburden was removed. In one area, the core trench was excavated through 61 m (200 ft) of soft wet silt and clay. The dam axis crosses two deep buried channels and adjustments were made in the design to suit field conditions. Electroosmosis treatment was used to stabilize the core trench cut slopes in the area of the soft wet silt. Extensive field and lab testing was carried out to determine the density and strength of the overburden material. Empirical and analytical methods were used to assess the liquefaction potential under seismic loading of the silt/clay and fine sands under the shells of the earthfill dam.The Revelstoke earthfill dam was about 57% complete by the end of 1981. The construction has proceeded well and is on schedule. It is expected that the earthfill dam will be completed by mid-1983, well in advance of proposed reservoir filling in the fall of 1983. Keywords: excavations embankment design, foundation treatment, liquefaction, construction, electroosmosis.