Abstract:

Based on Yin-Graham’s 1D elasto-viscoplastic model which can predict both primary and secondary consolidations, the long term settlements caused by triangle periodic loading during road service period are theoretically studied. The expressions of total settlement and post-construction settlement of road embankment on soft clay produced by the triangle periodic loading during its service period are achieved. The relationship between the long term settlement considering fluid-solid coupling and that without considering fluid-solid coupling under the triangle periodic loading is analyzed. It is proved that the soft clay has the behavior of which the ultimate settlement when periodicity trend to infinite is not affected by the fashion that stress increases with time under the triangle periodic loading. Based on the expression of the total settlement proposed in the paper and the physical parameters of clay for a definite engineering, the total settlement of road embankment during its service period is numerically calculated. The critical settlement of road embankment at the start of its service period can further be determined from the total settlement at the end of its service period. From the above results, a required settlement standard is provided for rationally determining the start time of road pavement in the construction of expressways.

Key words: settlement of road embankment, triangle periodic loading, primary and secondary consolidations, elasto-viscoplastic model