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The flow function of an iron ore material governs its flowability characteristics in material handling chains 4 of the resource industry. A uniaxial compression test is able to obtain a flow function more rapidly comparing to the 5 Jenike direct shear test, nevertheless, results often exhibit lower rankings using the former method. This study aims to 6 investigate the fundamental stress states within the test specimen that led to this phenomenon, and to introduce a new 7 uniform density specimen preparation method for a uniaxial compression test in order to achieve comparative flow 8 functions as per a Jenike direct shear test. The minimisation of the wall friction effect and the achievement of the critical 9 state when preparing a uniaxial specimen were explicitly discussed. Experimental investigations on flow functions of a 10 suite of Australian iron ore samples were conducted using both the uniform density uniaxial compression test and the 11 Jenike direct shear test. Results from both methods were indicated to be comparable providing the specimen exhibited cohesive flow behaviours. Additionally, a simple compressibility indexl, based on the bulk density test of iron ore samples, was derived as a threshold to indicate if a uniform density uniaxial compression test can produce flow functions matching the Jenike direct shear test. The outcome of this research enabled a rapid and reliable flow function testing method for cohesive iron ore materials.

Economic drives dictate the exploitation of formerly less attractive ore bodies located close to or even beneath the water table. These ores can cause handling problems and expensive downtime of processing equipment due to their increased adhesive characteristics and are colloquially termed as "wet and sticky" ores. In order to gain a better understanding of the causes of poor handleability, experimental test methods for wall and inter-particle adhesion within bulk solids samples were developed and validated. The results confirmed that adhesion of bulk solid to equipment surfaces is mainly governed by capillary pressure. It can therefore be described using the Young-Laplace equation, which implies that adhesion is primarily dependent on the interfacial water between bulk material and the adhesion partner. Accordingly, the governing material parameters of adhesion are its capillarity and permeability, as these two characterize water transport to or from the interface of the adhesion partners. Furthermore a threshold for the classification of a material as wet and sticky based on the measurements of adhesion has been proposed.

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