A simplified axisymmetric model for column supported embankment systems

• Published in: Computers and geotechnics Vol. 92; pp. 96 - 107
• Main Authors: Zhao, Lin-Shuang, Zhou, Wan-Huan, Yuen, Ka-Veng
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 01.12.2017; Elsevier BV
• Subjects: Axisymmetric model; Case studies; Column supported embankment; Columns (structural); Computer simulation; Cylinders; Deformation; Deformation effects; Deformation mechanisms; Embankments; Finite element analysis; Finite element method; Height; Load transfer; Mathematical analysis; Mathematical models; Modulus ratio; Shape functions; Shear stress; Soil; Soil investigations; Soil layers; Soil stresses; Soils; Stress analysis; Stress concentration; Stress distribution; Stress ratio; Studies; Vertical distribution; Modulus ratio; Axisymmetric model; Column supported embankment; Load transfer; Stress ratio
• ISSN: 0266-352X; 1873-7633
• DOI: 10.1016/j.compgeo.2017.07.027

In this study, a simplified axisymmetric model is built to simulate a column supported embankment system. The model is based on a cylindrical unit cell that contains one column with the surrounding soil and a layer of overlying embankment fill. The deformation of the column with the surrounding soil is simulated using a deformed shape function. The embankment fill is divided into an inner cylinder and an outer hollow cylinder to simulate the soil arching effect. The stress continuity and volume deformation continuity are applied to combine the behavior of the embankment fill and that of the column-reinforced foundation together. A semi-analytical solution is obtained, and it is verified using a finite element analysis and a case study. After that, parametric studies are put forward to evaluate the load transfer mechanism within the embankment fill, the shear stress at the interface between the column and the surrounding soil, and the vertical stress distribution within the column. The influences of the column modulus, the spacing between columns, the height of the embankment fill, and the length of the column on the soil arching effect are investigated and discussed. It is concluded that when the column modulus becomes larger, the stress ratio between the column and the surrounding soil increases correspondingly. The height of equal settlement plane is close to the net spacing between columns, but it changes slightly with a change in the column modulus.