Froude modeling, where strength and modulus properties and surface overpressure scale as the length scale, is a potential method for determining the structural response of underground protective structures at overpressures in excess of existing laboratory devices provided the strength and modulus properties can be adequately scaled. The results of this study indicated that Froude model tests on silo-type structures in dry sand under one-dimensional plane wave loading could predict the loading response of a prototype constructed using a length scale of three. The primary contribution of this study was to focus attention on the necessity of scaling the unloading soil moduli if Froude modeling is to successfully predict the time-history of a soil-structure system whenever the characteristics of the problem (loading, geometry, etc.) are such that unloading occurs in the soil.