The Influence of Water-Level Fluctuation on the Instability and Seepage Failure of Dump-Fill Cofferdam

Due to the double disturbance effect of dredging and filling, there will be a problem with weir slope stability after formation fill type saturated clay weir. In order study influence water-level fluctuation on instability seepage failure dump-fill cofferdam, saturated-unsaturated theory strength reduction method are embedded into finite element system such that fluid-solid coupling cofferdam is analyzed. The results show can revealed by analysis excellently. variation saturation line consistent rising, but change response has lag property during decline process in water level changes faster. maximum displacement approximated as two stages, namely, stable growth stage accelerated (slip initiation), which more obvious. Based analysis, most dangerous sliding surface located at position horse path, critical coefficient approximately 1.475. possibility increased if exceeds height impermeable wall.