A LOGNORMAL SIZE DISTRIBUTION MODEL FOR ESTIMATING STABILITY OF BEACH FILL MATERIAL

摘要

This report discusses the problem of estimating the "extra amount" of beach fill to be used when the available borrow material characteristics are finer than the native sand composing the beach area. It is shown that an estimate of the extra amount of fill needed can be found if the native or design sand is better sorted than the available fill, regardless of whether the mean grain size of the borrow material is finer or coarser than the native sand. However, if the available fill is better sorted than the native, or design sand (again regardless of the relative mean grain sizes), there is no direct mathematical solution to the problem. In these latter cases, until further guiding criteria can be developed, past experience and other empirical data are required in reaching a practical decision regarding the amount of the fill that will be stable when emplaced on a given beach.