一、研究意义近年来,随着交通基础设施建设的迅猛发展,我国如长珠三角洲、汉江平原等地区高等级公路建设中优质路基填料匮乏的难题日益突出。这些地区地势平缓,河网纵横,农田湖塘众多,公路路基形式大部分为路堤,往往比其它地区需要更大量的填料。就地取土不仅占用耕地,而且填料质量难以保证;长距离运土,会造成建设成本的大幅增加。另一方面,这些地区大多拥有较丰富的江(河)砂资源,用砂填筑路基不仅可降低成本,也可以保证填筑质量。但河砂 I. Significance of Research In recent years, with the rapid development of transportation infrastructure construction, the problems of lack of high-quality subgrade filling in high-grade highway construction in our country like the Pearl River Delta and the Han River Plain have become increasingly prominent. Flat terrain in these areas, river network aspect, many lake farmland, road embankment in the form of mostly embankment, often require more than other areas of the filler. Taking soil locally does not only occupy the cultivated land, but also the quality of the filling material is difficult to guarantee; transporting soil with long distances will cause a substantial increase in the construction cost. On the other hand, most of these areas have abundant river (river) sand resources. Using sand to fill subgrade can not only reduce costs but also ensure the quality of filling. But river sand