Measuring the tensile strength of gold tailings

This paper discusses the modification of the Brazilian disk test so that it can be applied to measure the tensile strength of unsaturated soils. The study involved testing the tensile strength of unsaturated gold tailings prepared across a range of moisture contents. In order to monitor the initiation and propagation of cracking within each sample, Particle Image Velocimetry (PIV) was utilised. The study revealed that across the range of moisture contents considered the Brazilian disk test, performed with curved loading strips, consistently resulted in cracking initiating in the centre of the sample, thereby validating the measured failure load as the result of a tensile failure. An investigation of load-displacement relationships for all samples tested showed that in the pendular regime, the behaviour of the material was particularly erratic. However, at higher saturation levels, material behaviour was found to be significantly more stable.