Field-Testing of Structure on Shallow Foundation to Evaluate Soil-Structure Interaction Effects

A simple test structure was designed and constructed to facilitate forced-vibration testing of a shallow foundation experiencing combined base shear and moment demands. The structure consists of a reinforced concrete foundation and top slab separated by steel columns that can be configured with braces. The slabs have a 2:1 aspect ratio in plan view to facilitate variable amount of overturning for shaking in orthogonal directions. The structure was transported to two field sites with representative shear-wave velocities of approximately VS= 95 m/s and 190 m/s. At each site, the foundation slab was cast-in-place. Forced vibration testing was conducted over a wide range of frequencies and load levels to enable the evaluation of foundation-soil stiffness and damping behavior for linear and nonlinear conditions. The data collected to facilitate such analyses include acceleration, displacement, and foundation pressure records (data can be accessed at DOI: 10.4231/D3NK3658M, DOI: 10.4231/D3HT2GC4G, DOI: 10.4231/D3D21RK0N).