Impacts of Fixed-End and Flexible Boundary Conditions on Seismic Response of Shallow Foundations on Saturated Sand in 1-g Shaking Table Tests

A key consideration in physical modeling of seismic problems geotechnical engineering is the impact model container boundaries on soil layer response. The may alter stress-strain behavior from free-field conditions through possible reflection incident shear waves and generation P-waves within layers. In this study, 1-g shaking table experiments were performed to evaluate impacts boundary response saturated loose sand layers subjected harmonic base motions (1) in a condition, (2) with shallow foundation, (3) with foundation supporting single degree freedom superstructure. formed newly fabricated laminar that can be converted rigid box by adding elements end walls. Acceleration, excess pore water pressure, settlement measurements demonstrate rigidity have major models. particular, observed permanent foundations increased 58–115 % models with fixed-end (or rigid) compared those flexible conditions. This was attributed nonuniformity strains near higher level energy trapped inside model. Furthermore, spectral accelerations captured tests Scaling issues associated testing also discussed.