近年来 ,苏州的污水管道曾发生过多起沉管事故。这些发生事故的污水管道多铺设在地下水位较高的粉砂土层或离粉砂土层较近的轻亚粘土层中(即易产生流砂的土层中 )。究其原因 ,有些因施工质量问题 ,但有一部分则是按《市政排水管渠工程质量检验评定标准》ＣＪＪ— 90 (以下简称 In recent years, there have been too many pipe sinking accidents in Suzhou’s sewage pipe. Sewer pipelines in these accidents are often laid in silt layers with high groundwater levels or in light-sub-clay layers (ie, soil layers that are prone to runoff) that are closer to the silt layer. The reason, some because of construction quality problems, but some are based on “municipal drainage sewer engineering quality inspection and evaluation criteria” CJJ-90 (hereinafter referred to as