SIMULATION ON SEEPAGE FIELD OF UNDERGROUND WATER IN YANKA DANGER SECTION OF JINGJIANG GREAT EMBANKMENT
荆江大堤盐卡险段地下水渗流场模拟研究

The Yanka section of the Jingjiang Great Embankment on the north bank of the Yangtze River is one of the zones with piping hazard in flooding seasons. Seepage fields of ground water at different river water levels are simulated by using the software of Visual Modflow developed by US geological survey. Different treatment models,such as models of presence of scuttle,seepage-proof walls,pressure-reducing wells and chaning the seepage coefficiency of artificial filling,are studied at high water levels. The results show that (1) a decrease in seepage coefficiency of artificial filling will reduce the seepage damage significantly in the high water level,(2) reducing of pressure wells has significant effect on preventing piping if ponds or scuttles are present,and (3) seepage-proof walls are effective against seepage damage if the walls reach the clay layer in the middle (about 20m in depth).