SEEPAGE, STATIC AND DYNAMIC COMPUTATION IN SELECTING CORE TYPE OF A 300 M HIGH EMBANKMENT DAM BETWEEN VERTICAL AND SLOPING CORE

摘要

By incomplete statistics, there are 12 over-230-m-high dams made of local material in the world, which are being built or have been built, and the types of their anti-seepage core are mainly soil vertical core and sloping core. A being planed rockfill dam with core is 310m high, an extra-high dam, and its core type should be decided considering many factors. By Seepage FEM analysis, the Water Head Gradient of sloping core is larger than that of vertical core, yet the gradient in both dams and their foundation doesn't exceed the allowing gradient. Static analysis shows that the sloping core can better prevent hydraulic fissure yet both types are safe because the clay core is sophisticated with gravel. By Dynamic FEM analysis, two type cores have the equal aseismic capability, and because the dam site is in low intensity seismic area, both dams' dynamic response is not intensive. The computation shows that seepage, static and dynamic issues are not the key factors in selecting the core type. The scope of foundation treatment and filling quantity of rockfill dam with sloping core are larger than those of rockfill dam with vertical core, which leads to additional 170 million Yuan investment, so vertical core is adopted.