How does the arch concrete of the tunnel be poured up? How can the support be used before the casting? Is it made of I-beam? Is it directly supported by earthwork?
Small pipe or large and medium pipe shed is advanced support, used for surrounding rock crushing area, or into and out of the hole, of course, grouting, without grouting, lost the significance of shi.
The excavation of the tunnel face, slag, to the primary support system, first hit the bolt, then use steel or steel made of steel, installation support in tunnel contour, and then sprayed concrete (poor surrounding rock hanging steel mesh, then sprayed fiber concrete).
Two concrete tunnel lining, template is used according to the size and shape of the tunnel design custom-made, I-beam welded frame, welded steel plate, known as the "two trolley liner" (hydraulic jack lifting and installation of steel wheel moving on the rail), is generally the length of 9~12m, concrete pouring pump concrete.
