SPECIAL-SHAPE SECTIONS Russian patent published in 1997 - IPC

FIELD: mining industry. SUBSTANCE: this relates to propping of underground workings by means of pliable supports made up of interchangeable special-shape sections. Special-shape section has incline side walls with flanges and rectilinear bottom of width which is equal to total thickness of flanges. Bottom is conjugated with side walls by its cylindrical surfaces. Curvature radius of outer cylindrical surface is taken from range of R₁= (0,2-0,5)d, and curvature radius of inner cylindrical surface is determined by following relation: . With that, thickness of side walls of special-shape section is equal to d₁= [d-(R₂-R₁)(1-sinα)]sinα, where d - thickness of bottom of special-shape section equal to height of flanges; α - incline angle of side walls to axis of symmetry of special-shape section. EFFECT: high efficiency. 2 dwg