Abstract

The flexible roadway support frame Fig. 1 equipped with roof-bar arches(l) and sidewall arches (2) connected with each other by means of double-yoke stirrups with overlap (3, 4, 5) characterized in that each arch has a cut-out in the flanges located at the ends of those arches Fig 2.

IPC Classes  ?

• E21D 11/22 - Clamps or other yieldable means for interconnecting adjacent arch members either rigidly, or allowing arch member parts to slide when subjected to excessive pressure