管涌与滤层的研究(Ⅱ): 滤层

对管涌和滤层两个相关联问题的研究和发展过程进行了综述和评论;同时也给出了过去的研究成果,并与之进行比较。在滤层研究方面,指出了由平均粒径一点控制到两点和级配曲线多点控制的发展趋势;研究表明:太沙基的滤层规格比较保守,应结合内外水动力学研究砂砾滤层和织物滤层的适用规格。而粘土的滤层设计,关键是看能否发生贯穿性裂缝,其设计思想悬殊;井管滤层的淤堵失效应研究抽洗复苏的良策。

Study on piping and filters: part II of filters

The studies with development of piping and filters, two mutualized problems, are reviewed. Meanwhile our studied results are also given for comparison. This part II, with respect to filters we indicate that the developing tendency of controlled grain size is one point of average grain size first and then to two points as well as to many points along the grain size grading curve. Terzaghi’s filter criterion is conservative and it should be revised by hydrodynamics in spite of sand gravel filter or geotextile filter. When filter used to protect clay the key problem will be cracked or not and the design criteria for these two situations are very discrepant. As to clogging of filter, such as relief wells, the suction washing method to restore the drainage effect is the better.