A simple L-shape pipe flow test for practical rheological properties of backfill slurry: A case study

Abstract

Cemented high-density or paste backfill is commonly used in underground mines. The slurry is pumped or gravity-fed into the stope through a pipeline. The pipe flow is completely dominated by its rheological properties. For practical applications, a complicated and expensive flow loop test is generally required to determine the industrial rheological properties. To find a more easily applied, alternative method, a case study using a simple slump, bleeding, and L-shape pipe flow test is presented to determine the industrial rheological properties. Tests were conducted with different proportions of limestone addition CA3, and different solid mass concentrations Cw. The results show that a stable homogeneous flow is achieved when CA3 exceeds 10–15% and Cw>80%. The yield stress and viscosity are smaller than that measured from a rheometer. An industrial test was performed for verification. The measured im fluctuates close to the predicted im while a traditional method overestimates the pressure loss.