Challenge to propose a new erosion failure criteria of soil

为了研究作为土元的土的侵蚀破坏现象，研制了一种试验装置。该装置可以施加任意围压和内水压，并通过从管道开口溢出土壤颗粒来重现土壤的侵蚀破坏。通过使用该仪器，可以评估土壤材料对侵蚀破坏的抵抗力。实验结果发现，初始围压越大，土壤颗粒的侵蚀速度越小，围压对侵蚀破坏也有实验影响。

To study a phenomena of erosion failure of soils as a soil element, an experimental apparatus was developed. The apparatus make it possible to apply arbitrary confining pressure and internal water pressure, and to reproduce erosion failure of soils by spilling out soil particle from the opening of pipe. By using the apparatus, it is possible to evaluate the resistance of soil material against to erosion failure.As a result of the experiment, it was found that the larger the initial confining pressure, the smaller the erosion velocity of soil particles, and it was also found that the confining pressure effect on erosion failure experimentally.