Active Arching of Sand During Dynamic Loading: Results of an Experimental Program and Development of an Analytical Procedure

摘要

The ultimate purpose of this study of soil arching is to enable the economical design of reliable underground protective structures. Idealized small-scale structures were embedded in prepared specimens of dry sand, and long-duration, dynamic overpressures of various magnitudes up to 440 psi were applied to the surface of the sand. Foundation area and depth of soil cover over the structures were the primary variables during the tests. Measurements were made to evaluate the interrelationships between depth of soil cover, dynamic overpressure, soil stiffness, structural response, and soil arching. Soil arching over a particular soil-structure system subjected to dynamic loading was found to be a function of the geometry and the relative stiffness of that system. The geometry is accounted for by the perimeter-area ratio of the structure multiplied by the depth of the soil cover. The stiffness portion of the factor relates the soil stiffness to the stiffness of response of the structure relative to the free-field soil. (Author)