The Ground Reaction Curve and Mobilization of Soil Arching in Geosynthetic-Reinforced Column-Supported Embankments: Fid-Bau Portal

The Ground Reaction Curve and Mobilization of Soil Arching in Geosynthetic-Reinforced Column-Supported Embankments

McGuire, Michael P. / Sloan, Joel A. / Hunstein, Eric M. / Socolofsky, Luke

This paper presents a method to develop a Simplified Ground Reaction Curve (SGRC) for 3D vertical load transfer associated with soil arching in column supported embankments (CSEs). The SGRC is comprised of three piecewise linear relationships for the normalized differential settlement between columns and the normalized vertical stress between the columns. The differential base settlement is normalized by the column diameter to establish a percent relative displacement as opposed to plane strain trapdoor tests which use the clear span. Peak arching is modeled using approximations of the Concentric Arches (CA) or Hewlett and Randolph (HR) models, while terminal arching is modeled using the Adapted Terzaghi (AT) model. The Approximate Concentric Arches (ACA) and Approximate Hewlett and Randolph (AHR) models were developed herein using fitted relationships between the AT model for arching and the CA and HR models. The ACA and AHR models are assumed to be applicable to triangular as well as rectangular column arrangements. Measurements of the load transfer due to soil arching in full-scale CSEs were used to compare the predictions using the SGRC to those using the AT, ACA, and AHR models alone. Based on the results of the comparison with 13 measurements from five case histories, the authors do not see a compelling reason to use an SGRC due to the added complexity and lack of performance gains over simpler options such as the Bilinear Adapted Terzaghi (BAT) method used in Load-Displacement Compatibility Analysis.