Stability of high rockfill embankment based on orthogonal test and numerical simulation

Abstract

The parameters of rockfill materials are important factors that influence the stability of high rockfill embankment. However, the influencing laws of parameter changes on the deformation of high rockfill embankments still remain unknown. To deepen understanding on the influencing laws of parameters of rockfill materials on the stability of high rockfill embankment, a case study using an orthogonal test and numerical simulation was conducted on the high rockfill embankment with 50.6 m banking in the secondary road reconstruction project of the national highway 316 from Xunyang to Ankang in the Shaanxi Province of China. The influences of elasticity modulus, dry density, Poisson's ratio, frictional angle, and cohesion on the stability of high rockfill embankment were analyzed. A three-dimensional numerical model of high rockfill embankment was constructed using FLAC3D, and a numerical simulation of the embankment deformation was performed using the maximum settlement of embankment as the evaluation index. The influences of different factors on the deformation of high rockfill embankment were evaluated through a numerical simulation based on the orthogonal test to verify the accuracy of the orthogonal test. In addition, the deformation law of high rockfill embankment was examined. Research results demonstrate that dry density predominantly influences the stability of high rockfill embankment, followed by elasticity modulus, Poisson's ratio, cohesion, and frictional angle. The optimal combination of parameters of rockfill materials was concluded from further analysis. The numerical simulation and orthogonal test results are consistent. The top surface of the high rockfill embankment develops settlement deformation during the construction period, accompanied by outward lateral squeezing trend at the foot of slope. The vertical deformation consists of settlement first and then upheaval. Research conclusions can provide some references for the reasonable selection of rockfill materials for embankment and the stability analysis of high rockfill embankment.