MECHANICAL PROPERTIES ANALYSIS FOR A FLEXIBLE ISOLATION LAYER MATERIAL IN MULTIPLE FUNNELS SYNCHRONOUS ORE DRAWING BASED ON A INDOOR MODEL EXPERIMENT

The development of mechanical properties of a flexible isolation layer material in ore drawing from multiple funnels is the foundation of ore drawing mechanism. The tensile stress and compressive stress of an isolation layer were measured using an indoor model experiment, and the mechanical properties and rupture condition of isolation-layer materials were analyzed. The results show that:1) in the transverse direction, with the increase in distance between measuring points and center point in an isolation layer, tensile stress changes sinusoidally; compressive stress decreases gradually and the friction changes cosinoidally; the isolation layer on cavity is not affected by its supporting force, and the variation law of the supporting force in other parts is the same as compressive stress; and 2) in the longitudinal direction, all forces acting on an isolation layer increase with the descending height; average tension stress increases exponentially before contacting funnels in the bottom of the model; correlation between the maximum tension stress and the descending height is σ_smax=-0.32+0.32e^0.005h, and failure point satisfies equation of s=±30.12 cm.