Conditions should be met before construction:
1. The exact location of underground communication and signal cables must be mapped before starting work, and at the same time contact the relevant units to take necessary protective measures to prevent damage.
2. Before the jacking construction, you must contact the railway property right unit to go through the relevant procedures in advance.
1. Construction sequence:
Mainly adopt sequential construction:
Reinforce the existing line first—excavate the working pit, make the slide plate and the back—jack the concrete pipe—finish the project II. Construction method: (1) Reinforce the existing line:
There is 1 transverse rail bundle, 5.5 meters long, and 79 rail bundles; each longitudinal rail bundle has 9 rails, 25 meters long.
(2) Excavating work pits, making skateboards and backs:
Manually dig the working pit, manually trim the corners, and make the installation back. The working pit is equipped with guiding devices, a protective shed is set on the pit to keep out wind and rain, cofferdams are set up with woven bags according to the requirements to block rainwater, steel plates are set in front of the backrest, jacks are arranged in front of the pipes, and support beams are set in front of the pipes, and the hydraulic pump stands outside the pit , jacking in,
Replace the top iron manually. (3) Concrete pipe jacking:
Excavation and jacking work should be carried out alternately. Manual excavation, trolley soil transportation, manual soil transportation, manual loading, dump truck soil transportation, jacking, electrical lighting. Level control center and slope.
(4) Finishing of the project:
After the jacking operation is completed, the back is removed, the site is cleaned up, and the remaining materials are recycled. 3. Technical measures: (1) Reinforcement of existing lines:
According to the relevant requirements of the Harbin Railway Bureau, the line is reinforced with buckled rail beams, and the "Railway Technical Operation Regulations" and relevant regulations must be strictly followed during construction. (2) Excavating work pits, making skateboards and backs:
Before and after the excavation of the working pit, its axis and sidelines should be accurately measured. Making the bottom plate and concrete backrest:
1. The surface is required to be flat, and the flatness is ≤5mm.
2. The bottom plate is made downhill to ensure the downhill slope of the pipe jacking, and the deviation of the on-site measurement of the elevation shall not exceed ±30mm. (3) Concrete pipe jacking:
1. Check the hydraulic system carefully before each jacking.
2. The bottom of the pot should be dug in front of the jacking and excavation. The depth of the footage depends on the soil quality and should not be greater than 40cm. The depth is even and consistent to prevent direction deviation.
3. During the entire jacking process, the axis should be observed for each jacking stroke of the pipe jacking, and measures should be taken to correct the deviation in time if any deviation is found.
4. If it is found that there is a large deviation between the left and right of the pipe jacking during jacking, it can be adjusted by increasing or decreasing the jacking force on one side or by digging.
5. If it is found that the jacking pipe is too high or too low during jacking, it can be adjusted according to the following methods. High adjustment:
(1) The overcut at the front end is slightly lower than the bottom plate and gradually adjusted.
(2) If the excavation is not wide enough and the amount of soil eaten is too large, when the pipe is raised, over-excavation can be performed on both sides.