STABILITY ANALYSIS OF WIDENED-EMBANKMENT BASED ON STRENGTH REDUCTION FINITE ELEMENT METHOD

摘要

The stability of high-grade highway widened embankment was analyzed by the application of strength reduction of the AB AQUS finite element method. The non-linear elastic-plastic finite element model of the stability analysis of the widened embankment was established. The soil parameters of the old and new embankment and foundation were determined by density test, direct-shear test and triaxial compression shear test. The criterion of widened embankment instability was suggested that is having a rapid increase of displacement on the maximum displacement curve of the widened embankment surface changed with strength reduction coefficient, and appearing a plastic run-through region on the widened embankment section at the same time. The instability criterion has a clear physical meaning. The stability safety factor of the widened embankment was calculated based on the instability criterion. The results were compared with that of the limit equilibrium method. The results show that: the real most dangerous slip surface is a slip region that has a certain thickness. The safety factor results of widened embankment stability calculated by strength reduction finite element method are basically the same with that by the limit equilibrium method. The proposed widened embankment instability criterion is reasonable and has a clear physical meaning. The application of the slow slope, or step slope on widened embankment for improving the stability of the embankment are very good.