PL409609A1 - Flexible flattened steel arching - Google Patents

Abstract

Flexible casing flattened with girder and side-arc arches bent over three radii so that the girder hook (1) and the diagonal arc (2) has an oblique symmetry axis (O2) whose angle to the vertical axis (O1) is equal? =? / 2 + ß +? / 2 with a size of 45 ° ± 5 °, where the arc is bent over a radius (R1) on the arc (R1) on the angle (ß) of the arc is bent over a radius (R2) on the angle (?) of the arch is bent with a radius (R3), with the arc section (L1) from the end of the section (CO) of the joist of the girder arch (1) and the sidewalk arch (2) to the line (O3) of the end of the girder arch (1) bent radius (R2) on an arc with an angle (ß) has a length on the arc (L2) of no more than 250 mm. The side arch (2) has a straight length (z) behind the horizontal line (O4) determined from the height of the enclosure door (W). The straight line can be directed perpendicular to the floor or directed outwards by changing the position of the line (O4) or by increasing the length of the overlap (CO). On the length (CS) of the girder arches tab (1), the casing has four stirrups (3), and on the length (CO) of the girder arches overlap (diagonal) has two stirrups (3). Enclosure shafts, thanks to the shape of the arches and their connections, obtain high strength parameters, more flexible work on joints, and secure ceiling protection during the assembly phase in the mining excavation.