In the construction of the tunnel, the positioning of the trolley is a very important step. Before the lining trolley is used in the tunnel for the first lining, the positioning of the trolley must be done well, so that the trolley is aligned with the center line of the tunnel. There is no problem with the positioning of the trolley. The following construction work can be carried out. If the positioning is wrong, the subsequent work may need to be adjusted. What are the positioning operations of the lining trolley?
Positioning operation of lining trolley
1. Carry out an inspection
Before positioning, check the electrical, hydraulic, and walking systems. Before pouring the lining trolley, clean the trolley template and apply a release agent.
2. Determine the parking location
When positioning, the surveyor uses the instrument to determine the parking position of the trolley. After the parking position is determined, in order to prevent the trolley from shifting due to vibration during the lining process, a trolley stopper can be used to fix the walking wheels.
3. Fixed elevation and horizontal plane
Raise the gantry to the required elevation and level it, fix the adjusted elevation and the horizontal plane, check it 2 to 3 times during the lining process, to prevent loosening when the force is transmitted downward to the ground, causing deviation.
4. Align the template assembly to the center line of the tunnel
Connect the template assembly to the center line of the tunnel. The template assembly can be moved horizontally on the gantry to align the template with the center line of the tunnel. After the template assembly is aligned to the center line, it is allowed to move ±100mm on the gantry. This can reduce The force of the small portal in the longitudinal direction of the tunnel.
5. Place the side mold cylinder
The dimensions are checked by the surveyor to make the side mold close to the side wall foundation. The side mold cylinder is equipped with a shut-off valve. After one end of the side mold is in place, the cylinder shut-off valve can be closed to stop the action. Place the other end cylinder to the required position according to the above operation , Pay attention to open the shut-off valve when demolding.
6. Adjust the longitudinal straightness of the side mold
Use a screw to adjust the longitudinal straightness of the side mold to a suitable position and tighten the bottom support screw. The place where the screw is supported must be safe and reliable. The bottom of the side mold must be reliably supported on the ground regardless of the construction of the ground screw. , So as to reduce the force on the mast system.
7. Welded I-beam
After the bottom mold is in place, the lining trolley screw rods are respectively supported on the bottom longitudinal beam and on the I-beam anchored on the ground. The anchored I-beam should be punched at least 3 before and after the I-beam at the force position and the diameter is not less than 18 mm. The rebars are welded together.
8. Fasten the lead screw
There are a total of 4 sets of screw rods for fastening the top mold of the formwork trolley and the mast system, and there are more than 8 sets of positioning screws between the upper longitudinal beam and the mast system. Remember that the force must be transmitted to the ground.
The above is the positioning operation of the lining trolley. After aligning the template assembly to the center line of the tunnel, the positioning can be considered as completed. The following steps are to better fix the railway structure and allow the force to be effectively transmitted to On the ground, it is also better to complete the next construction work.