Scour and Erosion. Proceedings of the 7th International Conference on Scour and Erosion

This paper introduces an experimentally based study into backward erosion piping. The motivations for and aims of the study are outlined and the experimental setup and procedures are described. Experimental challenges are highlighted and innovative methods to overcome them presented. New experimental techniquespresented include: a constant head tank capable of providing continuous head variation between 0.3 to 4.0m in 5mm increments; measurement of water velocity in inaccessible, small sand channels; preventing bio-clogging from interfering with the backward erosion process; and drying large quantities of sand in an inexpensive, time efficient manner. An account of experiment observations is given which groups the backward erosion process into 5 stages: fluidisation, tip progression, equilibrium, forward deepening and failure. Initial results are provided and compared to similar testing from other researchers to demonstrate repeatability and accuracy of the experimental setup and procedure. An outline of the intended future experiments is given including major test groups and their respective objectives and variables