Creep-Like Delayed Failure of Clayey Ground after the End of Embankment Construction
Even in normally or lightly overconsolidated clay foundations, failures have been observed some days/weeks after the end of the embankment construction. The clay foundation stays apparently stable just after the completion of construction, but with the passage of time instability develops gradually instead of expected consolidation and it may undergo catastrophic failure in an unexpected moment. In this paper such a creep-like delayed failure of a homogeneous normally consolidated clay foundation is investigated through the soil-water coupled finite deformation computation with the use of the invicid subloading surface Cam-clay model.
When the embankment loading is stopped at a point near the limit load, the foundation may experience failure with the elapse of time. The occurrence of delayed failure is due to the continued softening of soil that causes the increase of excess pore pressure. With time excess pore pressure isochrones expand until failure. When the end of construction load level is comparatively low, only the consolidation process proceeds.
KeywordsLimit Load Excess Pore Pressure Excess Pore Water Pressure Tangential Stiffness Matrix Saturated Clay
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