Arch for supporting roof of tunnel - is constructed from arch segments with compressible joints containing aerated clay

摘要

The roof of a tunnel or mine gallery is supported by arches made of corrugated steel sheet. These arches are made in segments (10,11) joined end to end with a pliable section (1) inserted between the end faces of adjacent arch segments. - The pliable section (1) is a hollow body with one side wall extending over the end walls. This side wall is shaped to match the corrugations of the arch segments. The hollow body is filled with a material such as aerated clay. This material has sufficient compressive strength to withstand normal loads, but in the event of a local collapse of the surrounding rock, the material is compressed so that the arch adjusts its shape to accommodate the change in loading conditions.