Abstract: In recent years, geotextile tubes have been widely used in the dewatering treatment of dredging slurry in rivers and lakes because of their good drainage reverse filtration performance, but they have the problem of slow dewatering rate in the later stage of dehydration. Therefore, physical model tests were carried out to verify the feasibility of using a pressurized vacuum pump to increase the later dehydration and consolidation rate of mud inside the geotextile tubes under the condition of adding flocculants. Meanwhile, the filtration and dewatering efficiency of the “aerodynamic oscillation method” and the “tube top loading method” were also compared. The test results and analysis show that: the “aerodynamic oscillation method” will cause cracks in the originally relatively dense mud in the geotextile tube, so that the airtightness of the mud in the geotextile tube will be destroyed. The “tube top loading method” increases the pressure of the mud in the geotextile tube, which improves the pressure gradient on both sides of the reverse filtration layer, so as to increase the filtration speed of the dredging mud. Vacuum filtration can significantly reduce the mud moisture content inside the geotextile tube and around the filtration pipeline, and the closer the filtration pipeline is to the center of the geotextile tube, the higher the filtration efficiency and the lower the mud moisture content.

Key words: hydraulic engineering; geotextile tube; slurry; vacuum filtration; dewatering and consolidation; water content

摘要： 近年来，土工管袋因其良好的排水反滤性能广泛应用于河湖清淤泥浆的脱水处理中，但在脱水后期存在脱水速率缓慢的问题。为此，开展物理模型试验验证在添加絮凝剂的条件下，采用增压式抽真空来增加土工管袋内泥浆后期脱水固结速率的可行性，同时还比较了“空气动力振荡法”与“管袋顶部加荷法”2种方法的抽滤脱水效率。试验结果及分析表明：“空气动力振荡法”会使土工管袋内的原本相对密实泥浆出现裂隙，使得土工管袋内泥浆的气密性被破坏；“管袋顶部加荷法”增加了管袋内泥浆压力，提高了反滤层两侧的压力梯度，使得清淤泥浆的抽滤速度提高；真空抽滤可以显著降低土工管袋内部、抽滤管道周围的泥浆含水率，且抽滤管道越靠近土工管袋中心，抽滤效率越高，泥浆含水率也越低。

关键词: 水利工程；土工管袋；泥浆；真空抽滤；脱水固结；含水率