Loss or significant deformation of a highway embankment could prevent access to a stable bridge, damage the first span of an otherwise stable bridge, or result in blockage or loss of a critical roadway. A rapid method of classifying and ranking numerous embankments along priority routes is crucial for delineating those embankments most in need of detailed assessment. Over 400 highway embankments and slopes along priority routes in western Kentucky were evaluated and ranked to determine critical embankments requiring further attention. Information evaluated for each embankment included height, slope angle, geologic formation, depositional environment, Soil Conservation Service soil unit, anticipated groundwater depth, liquefaction potential, and expected magnitude and peak ground acceleration for the 50 year and 500 year events. The ranking system model uses geometry, geology, and soil unit to estimate the yield acceleration of each embankment. The yield acceleration is divided by the anticipated peak ground acceleration to develop a yield factor. For yield factors greater than one, the risk is indicated by the magnitude of the yield factor, with larger yield factors implying lower risk. For yield factors less than one, and taking into account event magnitude, a series of equations developed for central U.S. ground motions is used to estimate potential deformation of the embankment. While not suitable for design, the method is useful as a means of ranking critical embankments for further evaluation.

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