Characterizing volumetric deformation behavior of naturally occuring bituminous sand materials

Abstract

Oil sand materials are natural bituminous sand deposits that are rich in bitumen or asphalt content to the extent that oil can be extracted from these deposits. The presence of high viscous bitumen content in the oil sand composition makes these materials problematic for field operations of off-road haul trucks and shovels. In this paper, volumetric deformation and bulk modulus properties are determined for three oil sand samples with bitumen contents of 8.5%, 13.3% and 14.5% by weight, using a newly proposed hydrostatic compression test procedure. The test procedure applies field loading conditions of off-road construction and mining equipment to closely simulate the volumetric deformation and stiffness behaviour of oil sand materials. Based on the test results, bulk modulus properties were characterized as a function of the applied hydrostatic stress for individual oil sand samples. When the entire test data were combined, nonlinear bulk modulus models were successfully developed to account for applied hydrostatic stress states, test temperatures, and bitumen contents for the three oil sand materials. Results from the bulk modulus models show that oil sands are influenced by temperature due to the bitumen contents. The anticipated use of developed bulk stress models should provide essential guidelines for predicting volumetric deformation behaviour of oil sand materials in the field.