Experimental investigations of the reactive strength of soil in the bed of a circular footing subjected to short-term dynamic loads

Conclusions1. The distribution of contact stresses along the foundation slab of a rigid circular footing in a sandy soil subjected to dynamic loads in a steady-motion regime is saddle-shaped in nature and agrees with corresponding literature data derived from static tests. In this case, an increase in contact stresses from 0.2–0.5 to 1.0–1.5 MPa at the center of the plate will effect a reduction of from 1.60–1.80 to 1.30–1.50 in the concentration factor; this is associated with the enhancement of the role played by plastic deformations in the bed.2. The reactive strength of the soil in the bed of a circular rigid footing subjected to short-term dynamic load can be represented in the form of Eq. (1). In this case, the computed velocity a1 should be determined with allowance for the actual σ1(ε) curve, which corresponds to the work of the soil beneath the plate under conditions of a certain deformation regime.3. Use of the hypothesis that we have cited will make it possible to predict with an accuracy sufficient for practical calculations the maximum loads on foundation slabs placed on the surface of the ground for structures, and the parameters of their motion under blast-induced loads of rather high intensity.