陡坡水库大坝渗透稳定性及渗透变形分析

陡坡水库存在大坝质量差、坝体发育大量裂缝、背水坡出现散浸现象、坝后沼泽化并形成一上升泉以及排水渠和鱼池有絮状析出物、渗漏量增大等问题，这些异常现象都是由坝体及坝基渗流引起的。在阐述坝体和坝基地质、水文地质条件情况下，分析了大坝渗漏成因及大坝的渗透稳定性，指出坝体实际浸润线及坝体渗漏量是不正常的，特别是1987年后当库水位高于194m，同一库水位呈上升趋势，这是反常的。坝基实际渗漏量异常，存在管涌和接触冲刷问题，尤其库水位低至193．84m，坝后上升泉仍有沙沸现象。上述现象表明大坝渗流是危险的，并分析了散浸、析出物、上升泉及沼泽化、坝肩及绕坝渗漏等现象的成因。

Analysis of seepage stability and deformation of dam for Doupo Reservoir

Some questions such as disqualification dam, many cracks in developing dam body, disperse-impregnation in the downstream slope of dam, forming ascending spring owing to marshization in dam back, wadding educts coming from drainage ditch and rearing pond and a lot of seepage amount were occurred. These abnormal phenomena were brought by the seepages in the body and foundation of dam. On the circumstances of describing the dam body, foundation geological and hydrogeological conditions, cause of formation of the dam seepage and seepage stability of the dam were analyzed. It is pointed out that the actual saturation line and seepage amount of dam body were abnomal. Especially, the reservoir level was beyond 194 m after 1987, that compared with beforetime, it was abnomal that the identical reservoir level tended to go up. The actual seepage quantity of the dam foundation was unconventional, there were the questions of piping of the highly permeable layer and contact erosion, especially, the reservoir level was under 193.84 m, sand boil in ascending spring behind dam appears. Therefore, the seepage of dam was dangerous. The reasons of formation of dispersed-impregnation and exudates in dam, ascending spring, marshization, the seepage of shoulder and by-pass dam were analyzed.