Nonlinear Solution of Steel Arch Supports

Steel arch supports are used widely in long workings in coal and ore mines. Their displacements are in difficult conditions often comparable with the size of the structure. Changes in the geometry of whole arch support including changes in the shape of a rod cross-section require geometric and physical nonlinear solutions. The paper is focused on methods for the geometric and physical nonlinear analyses of unyielding steel arch supports which are consisting of rolled open cross-sections. These methods are based on the knowledge of effective flexural rigidity which is defined as the function of acting internal forces. The direct stiffness method was used to solution first, but this method has some computational limitations. The modified force method was used for calculation as the second computational variant. This method can be successfully applied when the displacements are large. The results of the numerical analyses are compared with the values which have been experimentally obtained using strain-stress test of unyielding steel arch supports.