疏浚工程中常采用射流冲刷的方式辅助切削土壤,但面对不同土质时其效果差异较大.针对疏浚中常见的砂土和黏土两种土质,采用ALE(Arbitrary Lagrangian-Eulerian)方法对其射流冲刷过程进行了数值计算,通过实验验证了计算结果的有效性,比较了两种土质在射流冲刷下的坑深发展、冲坑形态和冲刷能耗.结果表明:两种土质的冲刷坑深在初始阶段均线性增长,相同冲刷速度下黏土的发展速度较慢;两种土质的冲刷坑形均具有相似性,冲刷黏土获得的坑形更为陡峭;随着目标坑深的增长,两种土质所需冲刷速度线性增加,获得相同冲坑深度时,黏土(剪切强度17 kPa)所需能耗达砂土的十多倍.%Water jets are used to aided-cut soils generally in dredging projects.However,the effects of aidedcutting have large difference on different soils.The ALE (Arbitrary Lagrangian-Eulerian)method was used to simulate the erosion process of sand and clay,which are both common soil in the dredging practices.Some experiments were performed to verify the numerical results.The development of scour depths,the scour shapes and the energy consumptions of the water-jet-erosion were compared between the sand and the clay.The researches reveal that,the scour depths develop linearly in the initial phase of erosion for the both soils,and the scour depth of the clay increases slower than that of sand at the same jet velocity.The scour shapes of both soils have similarity respectively,although the scour holes of the clay are relatively steep.The jet velocities increase linearly with the target depth of scour holes for the both soils.The energy consumption of the clay (the shear strength τf =17 kPa) is more than ten times that of the sand at the same scour depth.
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