Centrifugal Modeling of Transient Water Flow

The phenomenon of transient water flow in earth embankments is examined. State-of-the-art solution techniques and their shortcomings are outlined. It is hypothesized that better solutions are obtainable through centrifugal modelling of the process. An experimental program is described. In order to interpret the experimental results, theoretical scaling relations for quantities pertinent to transient water flow are developed through consideration of the basic independent variables governing the flow. Testing was conducted on a geotechnical centrifuge in a container specially constructed for the test series. Acceleration levels of 25 g, 37.5 g, and 50 g were used. Pore pressures were measured and recorded during the transient rise and fall of the headwaters by four miniature pressure transducers. From these data, histories of total head as a function of time and equipotentials during headwater rise and drawdown are plotted. Steady state flow rates are also measured. Analysis of the data leads to the conclusion that theoretical scaling relations are valid and that this method does indeed give a better understanding of the phenomenon of transient flow and may be useful in design practice.