Seismic Response Analysis of a Geosynthetic-Reinforced Soil Retaining Wall

The paper reports results from numerical experiments that were carried out to investigate the influence of reinforcement stiffness, reinforcement length, and base boundary condition on the seismic response of an idealized 6 m high geosynthetic-reinforced soil retaining wall constructed with a very stiff continuous facing panel. The numerical models were excited at the foundation elevation by a variable-amplitude harmonic motion with a frequency close to the fundamental frequency of the reference structure. The two-dimensional, explicit dynamic finite difference program Fast Lagrangian Analysis of Continua (FLAC) was used to carry out the numerical experiments. Numerical results illustrate that the seismic response of the wall is very different when constructed with a base that allows the wall and soil to slide freely and when the wall is constrained to rotate only about the toe. Parametric analyses were also carried out to investigate the quantitative influence of the damping ratio magnitude used in numerical simulations and the effects of distance and type of far-end truncated boundary. The response of the same wall excited by a scaled earthquake record was demonstrated to preserve qualitative features of wall displacement and reinforcement load distribution as that generated using the reference harmonic ground motion applied at 3 Hz. The lessons learned in this study are of value to researchers using dynamic numerical modeling techniques to gain insight into the seismic response of reinforced wall structures.