The Load Capacity Model and Experimental Tests of a New Yielding Steel Prop

As the mining depth increases year by year, the deformation and failure of deep roadway become more and more serious, and new support equipment with high supporting force and yieldable character is quite necessary for mining safety. In this research, a new yielding steel prop with high stable load capacity was introduced, which features sustaining large deformation in the field. Based on principle stress method and elastic-plastic theory, a mathematical model of load capacity was proposed for the new prop. The results show that the stable load capacity of the prop increases linearly with the increase of the effective number of the steel balls. Meanwhile, the stable load capacity of the prop increases initially and decreases afterwards with the increase of the radius of the steel ball. Under the fixed radius of the steel ball, the stable load capacity will increase with the decrease of the gap between the inner tube and the outer tube. The stable load capacity of the prop calculated using the theoretical model quantitatively agrees with that of the experimental tests, with only an error within 5%.