The rheological behaviour of vibratable castables is of great importance for their performance and practical application. This study assesses the reproducibility and accuracy of the conventional slump test in evaluating castable flowability. Three model vibratable castable formulations with q-values of 0.28, 0.31, and 0.34 were analysed. Key variables such as varying oil amounts on the vibration table and the influence of different operators on measuring spread dimensions were examined. Furthermore, the efficacy of 3D spread flow measurements using an integrated 3D camera was investigated as an advanced alternative to the conventional slump test. The system demonstrated sensitivity to oil quantity, with increased oil on the vibration table augmenting spread flow but also increasing measurement deviation. The findings also revealed a robust correlation between spread flow measurements obtained with calipers and those recorded using a 3D camera, thereby enhancing measurement precision. The 3D spread flow technique demonstrated superiority in capturing complex rheological behaviours, enabling the quantification and comparison of flow velocity and shear rate during vibration across different formulations. Each formulation displays distinct shear rates and flow profiles, underscoring variations attributable to differing q-values.
This study highlights the potential of incorporating 3D spread flow techniques into standard testing protocols, providing refined insights into the rheological properties and overall performance of castables. The advanced method enables the optimisation of castable formulations for industrial applications.