Prediction of Nonlinear Stress-Strain Relationship of Lightly Stabilized Granular Materials from Unconfined Compression Testing

AbstractThis paper examines the nonlinear stress-strain behavior of lightly stabilized granular base materials and presents a method to predict them based on modified and extended Ramberg-Osgood expression from unconfined compression (UC) testing. A typical granular material was lightly stabilized with 0.5–3.0% cement-flyash (CF) as well as with 1.5–3.0% slag-lime (SL) and tested in UC with internal deformation measurement setup. This study indicates that the proposed mathematical model can accurately predict the nonlinear stress-strain relationships of the lightly stabilized materials obtained from the experiments. The parameters involved with the proposed model were initial elastic modulus E0, 0.2% proof stress σ0.2, ultimate strain εu, and the exponents for quantifying the nonlinearity of the curves n and m. Values of all the parameters were determined from the experimental stress-strain responses and reliable regression relationships were developed between these parameters and unconfined compressive strength (UCS).