A portable erosion flume has been developed that is capable of estimating erosion threshold and erosion rate relationships for fine-grained specimens over the depth of a typical sample tube. This newly-designed apparatus is a recirculating flume capable of generating steady currents over the exposed section of the sample. In this paper, the erosion properties of two marine sediments have been determined and show a significant systematic variation with depth at centimetre scale that would have implications for the potential need for scour protection engineering. The tests showed that the critical erosion onset velocity doubled over the upper 200 mm of each sample, and the erosion rate fell by an order of magnitude. The increased erosion resistance with depth is consistent with the general trend of erodibility reducing with decreasing moisture content. Ignoring this depth effect when selecting design values of the erosion properties could lead to erroneous predictions of scour rate and extent around subsea structures, and unnecessary scour protection engineering costs.

已经开发出一种便携式侵蚀槽，能够估计典型样品管深度范围内细粒试样的侵蚀阈值和侵蚀速率关系。这种新设计的装置是一个循环水槽，能够在样品的暴露部分产生稳定的电流。在本文中，已经确定了两种海洋沉积物的侵蚀特性，并显示出在厘米级深度随深度的显着系统变化，这将对冲刷保护工程的潜在需求产生影响。测试表明，临界侵蚀开始速度在每个样品的上部 200 毫米上翻了一番，侵蚀速率下降了一个数量级。随深度增加的抗侵蚀性与可蚀性随含水量降低而降低的总体趋势一致。在选择侵蚀特性的设计值时忽略这种深度效应可能会导致对海底结构周围冲刷速率和范围的错误预测，以及不必要的冲刷保护工程成本。