Seismic Response of Low Height Embankment over Soft Foundation Clay

Low height embankments are widely used for construction of highways and rural roads in India. Sometimes, it becomes necessary to construct such types of embankment on soft foundation soil under unavoidable circumstances. In addition to the stability under static loading, seismic excitation very often plays a major role in the stability of such an embankment. So, to study the behaviour of such embankment under seismic loading becomes very important as the failures may lead to huge loss of property and life. The present study analyses the response of a low height embankment overlying soft foundation soil under seismic loading with the help of finite difference analysis using FLAC. The Mohr-Coulomb failure criterion is used to define the soil constitutive model for both embankment and foundation soil. A stiffer half-space has been considered below the soft foundation soil and the analysis has been performed varying the shear wave velocity of the stiffer half-space. Low to moderate level of shaking has been applied at the base of the stiffer half-space by scaling the original input motion of 1987 Loma Prieta earthquake.