The construction of highway embankments over deposits of amorphous peat and muck is made difficult by the low shear strengths, high compressibilities, and excessive amounts of creep typically associated with soils of this nature. This report begins with a review of the compression behavior of these soils, including a method for predicting embankment settlements from the results of laboratory tests. A soil testing program is then developed for the determination of parameters required for embankment design and construction. Field vane shear tests are recommended for the measurement of the undrained shear strength, and creep tests are recommended for calculation of the parameters required for settlement prediction. The report concludes with the presentation of a procedure for design and construction of embankments over amorphous peats and mucks. The procedure relies upon the use of stage loading, preloading, and in some instances geotextiles, to overcome the problems ordinarily encountered during construction over such soft soils. Design examples illustrating this procedure are provided.

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peat, muck, embankment, foundation, creep, settlement, stage construction, surcharge, geotextiles

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Performing Organization

Joint Highway Research Project

Publisher Place

West Lafayette, IN

Date of this Version