Architecture.
Before the excavation of the cavern,
1. Measure the center line and excavation contour line of the cavern according to the size of the design drawing.
When blasting excavation, shallow hole loose blasting should be used as far as possible to reduce the disturbance to surrounding rock.
The total number of joints of steel bars with the same section should not be greater than.
50%, and the connecting part should not be located in the vault.
2. The waterproof board set in the comprehensive tunnel should be double-sided at the junction with the tunnel waterproof board.
Welding, HDPE 107/96 double-wall perforated corrugated pipe is set around the wall foot and communicated with the longitudinal blind pipe of the tunnel.
Before processing the steel grating, the sample should be enlarged and the gap between the support and the surrounding rock should be sprayed.
Shotcrete is densely packed.
3. Circumferential construction joints are set at the joint between the plug wall of the comprehensive equipment cavern and the cavern.
The annular construction joint is equipped with back-attached water stop and embedded water stop. Caves as equipment caves
When, should be combined with the relevant professional drawings after the station construction.
2.3
Electric power special cavern
1 Waterproof board and geotextile shall be laid in the cavern, and the waterproof board of the cavern shall be the same as that of the tunnel.
The joint shall be welded on both sides and provided with annular footing.
HDPE 107/96
Double-wall perforated corrugated pipe and tunnel
The longitudinal blind pipe connection of the tunnel is introduced into the tunnel side ditch.
3. 1 When the cavern is located in the asymmetric section of Class IV surrounding rock, the reinforcement of the cavern shall be reserved.
3.2 The initial support and lining of the cavern adopt the same support parameters as the main tunnel.
3.3 Circumferential construction joints shall be set at the joint between the plug wall and the comprehensive cavern.
Set back-attached water stop and embedded water stop.
4 construction procedures and construction technology
4. 1 construction procedure
Tunnel cavern construction procedures:
Construction preparation → technical disclosure → survey and lofting → excavation of front wall.
Rock reinforcement → sectional excavation and support → on-site monitoring → periodic acceptance → lining,
Waterproof layer construction
→ Site cleaning → End.