摘要 |
1. Lattice girder for underground panel lining and shaft lining, with three parallel chord members (1, 2 and 3), which in cross-section form a triangle, being spatially fixed to one another by means of strengthening elements (4), characterised in that each strengthening element (4) consists integrally of a profiled bar bent into two triangles (5 and 6) inclined towards one another and running towards the chords members (1, 2 and 3), and that the corners of the triangles (5 and 6) are welded from the inside to the chord members (1, 2 and 3). |