| In severe earthquakes, foundations settle, retaining structures move and landslides occur. The plastic yield of soil, or large seismic soil pressures against the structures can cause the damage and the large movement of structures. The seismic responses of foundations, retaining structures, and buried structures are the result of soil-structure interaction. In order to study these problems, the seismic response of soil in the free field must be understood first.; In this dissertation, a simple elastic-plastic free-field stress solution is introduced. Based on this stress solution two different type free-field deformation solutions are derived, one is from plastic flow theory and the other is from nonlinear "elastic" theory. The closed-form solutions are derived for some special cases. As an alternative approach the free-field stress and deformation solution are also derived from a plastic strain hardening theory. The different deformation solutions are compared with each other and also compared with the measurement from shaking table tests.; The free-field stress and deformation solutions are applied in the analysis of seismic response of retaining structures. A simple kinematic method is developed to determine the seismic thrust and the pressure distribution of granular dry soil on the retaining walls with different wall movements: rotation about the top or the bottom of walls and horizontal translation. Here the plastic seismic response of soil in the free field is included for the first time in the retaining wall analysis. The results from analysis are compared to test measurements. |
