Abstract
Accurate assessment of the stability of natural slopes and earth structures during earthquakes has become a critical aspect of the safe and cost-effective design of several projects in seismically active areas in Taiwan. As an intermediately complicated and accurate approach, Newmark-type displacement method, capable of estimating permanent earthquake-induced displacements as a reliable index of slope performance, is widely adopted to evaluate slope stability under seismic loading. This approach, however, becomes unwieldy when hundreds or thousands of iterations are required for a regional assessment because the yield acceleration (ky), a key parameter of this approach, is estimated by trial and error in conventional slope stability analyses. To cut down the computational effort, we developed a simple procedure to directly evaluate the ky for both shallow and deep slope failures. The factor of safety (FS) of slopes under static condition is first calculated without any iterative procedures, then the ky is determined through the established correlation between FS and ky. The ky calculated by the proposed procedure corresponds well with that obtained by the trial and error approach and, thus, can be applied efficiently to a regional assessment with thousands of slopes.
