The wet shotcrete machine sequence in the tunnel is the first wall rear arch, which is segmented from top to bottom and is divided into sections. In the construction, according to the longitudinal direction of 3 4m, the width of the piece is about 2m, and each piece should be rotated horizontally from the lower part. After one injection, you can move up.
When there is a large concave part on the rock face, it should be sprayed flat; during the shotcreting process, the nozzle should be leveled first, then the nozzle is spirally or S-shaped slowly and evenly moved, and each circle is pressed in front of the country, and the diameter is controlled. At about 30cm, the length of each spray should be determined according to the concrete quick-setting effect to make the sprayed surface smooth and smooth; the injection time interval between the two layers is generally controlled at 15-20min, and the upper layer should be guaranteed to have a certain strength before the lower layer is sprayed.
