Stability Failure Modes of Rigid Column-Supported Embankments

摘要

Rigid columns such as vibro-concrete columns and reinforced concrete columns are widely introduced to reinforce soft subgrade under embankment. Centrifuge tests and numerical analysis were performed to study the stability failure mechanisms of the embankments on soft soil reinforced with a single-row or group rigid columns. The numerical analysis and centrifuge tests both indicated that the failure modes of rigid columns varied with column bending stiffness and strength, slenderness ratio, and toe embedment and subsoil conditions. The possible failure modes of rigid columns leading the stability failure of embankment include the following types: (1) the primary bending failure of the columns occurred near the interface of soft and hard strata, followed by the secondary bending failure within the upper part of the columns; (2) the primary bending failure of the columns was followed by a collapse of the upper portion of the columns toward the embankment toe; (3) soil flew around columns.