The tunnel support trolley is composed of 4 sections, each section is 3M long, the clear distance between sections is 1.5m, and the total length of trolley is 16.5m. The trolley can move in sections on the track structure without unloading and pushing. The support point adopts polyurethane rubber steel core wheel, which can not only ensure the force, but also ensure the convenience of movement and small resistance. The trolley groups (1, 2, 3, 4) are manufactured and hinged to ensure that the supporting trolley can walk in a small radius curve. According to the weight of the shield machine, the characteristics of the rock stratum, the clear distance between the upper and lower tunnels, and the thrust during the shield tunneling, the load acting on the lower tunnel segment is calculated, so as to determine the trolley length and the ultimate jacking force, And by specialized company organization processing, production.
Assembly and running of support trolley
After the components of the support trolley are transported to the construction site, they are assembled on the ground with 25t truck crane and 45t gantry crane. After the assembly, the gantry crane is used to lift to the underground battery car and fixed with two sets of hoists. Each unit is transported to the overlap area by the battery car, and finally connected into a whole in the overlap area. After the connection is completed, each group of hydraulic, circuit and pipeline connection and debugging.
In order to meet the construction requirements, after the trolley is assembled and put into the well, the mechanical and electrical department will organize the operators to carry out construction commissioning for the hydraulic system, walking system and support system of the trolley. The specific commissioning items are as follows:
1) Whether each valve and oil cylinder can move freely and the effective stroke of oil cylinder is reasonable
2) Whether there is oil leakage at the joints of the system pipeline;
3) Whether the oil pump and pressure instrument are normal and whether the hydraulic pipeline is normal;
4) Whether the hydraulic cylinder, support cylinder and propulsion cylinder work normally and meet the requirements of sufficient stiffness and strength.
5) Whether the hydraulic cylinder can be locked by hydraulic lock;
6) Whether the hydraulic pump station, oil pump and pressure instrument are normal, and whether the hydraulic pipeline is normal.
1) Whether the walking system can move freely, whether there is shaking, slipping and other phenomena
2) Whether the walking wheel or other walking devices are firmly connected and whether there is poor connection;
3) Whether there is oil leakage in the walking Jack and whether the stroke of the jack can meet the walking requirements.
1) Whether the supporting jack can meet the stress requirements
2) Whether the support stroke of the jack can meet the requirements
3) Whether the overall support system configuration of the trolley is reasonable and whether there is weak support area.
Specific construction scheme
Overall construction planning
According to the construction planning, the construction of the off-line tunnel is carried out first, and then the online tunnel, and the offline tunnel is constructed when the online tunnel is constructed The erection in the tunnel moves along with the excavation according to the excavation condition on the line.