The tunnel lining formwork is a special equipment that must be used in the secondary lining of the tunnel construction process, and is used for lining construction of the inner wall of the tunnel. There are mainly simple lining trolleys, full hydraulic automatic walking lining trolleys and grid-type lining trolleys; full hydraulic lining trolleys can be divided into side-arched arches, full-round needle-beams, bottom die-pins, full circles walk through and so on. Lifting slipforms, jacking slipforms and overturning are also commonly used in hydraulic tunnels and bridge construction.
First. Lining formwork structure
The lining trolley consists of three parts: the frame, the formwork and the hydraulic power system. By hydraulically installing the vertical mold and demolishing the mold, the full-section lining of the tunnel can be completed at one time.
1. Trolley frame
It mainly includes gantry longitudinal beams, beams, columns, diagonal braces, side links, top links and walking parts. In the case of meeting the requirements of strength and rigidity, the steel design is adopted to ensure the structure is reasonable and the processing is simple and rapid. The connection of each component is connected by bolts and knots, which is easy to disassemble and easy to transport.
The total length is 12m, divided into 8 segments, each segment is 1.5m long. Each segment consists of two side stencils and two top stencils in the circumferential direction. The entire trolley has a total of 32 templates. Each formwork consists of a panel, a skirt and a rib portion. This structure not only increases the overall rigidity of the formwork, but also increases the weight of the formwork, compared with the use of I-beam and channel steel.
The two top stencils are bolted together, which facilitates the installation, disassembly and adjustment of the stencil. The connection between the top template and the side template is hinged.
The template support is divided into two parts: vertical lifting and lateral stretching. The vertical lifting adopts 6 vertical cylinders for lifting and lowering, and the lateral direction uses 6 lateral cylinders for expansion and contraction. The vertical cylinders are flanged and the side cylinders are earrings. After the template is in place, it is supported by a screw jack. This support method ensures that the formwork does not retract or deform when it is lining.
4. Template translation mechanism
There are 2 horizontal hydraulic cylinders on the top of the trolley frame to adjust the lateral position of the template.
5. Subsidiary decoration
The accessory frame includes 6 gantry jacks, 4 top bracket jacks, hydraulic pumping station, walking mounting, workbench, lighting circuit and so on. The hydraulic pump station is designed as a vertical closed structure. The hydraulic pump is placed in the fuel tank, and the multi-way reversing valve is placed above the fuel tank for easy operation and neat appearance.
Second. The main technical parameters
The thickness of the panel is 12mm, the skirt is 12mm thick steel plate, and the rib is made of 70×50 angle steel. There are 4 attached vibrators and 4 concrete pouring spouts on the top of the template, and 24 working windows with a size of 500×450. The horizontal adjustment movement of the template is 150mm on the left and right.
2. Hydraulic power system
The pressure is 16 MPa and the flow rate is 14.5 L/min. The vertical cylinder has a cylinder diameter of 160 mm and a stroke of 400 mm with a hydraulic lock. The lateral cylinder has a cylinder diameter of 90 mm and a stroke of 730 mm with a hydraulic lock. Horizontal cylinder, cylinder diameter 90mm, stroke 300mm.
3. Trolley running
The trolley travels with motor drive, the running speed is 6.7m/min, and the traction is 39.13kN. 2 sets of Y112M-6 (2.2kW) motor, rated speed 940 rev / min; reducer model is DWPA147, speed ratio is 60:1; chain drive speed ratio is 2.932:1; wheel diameter is 400mm.
The above is the relevant introduction of the technical parameters of the tunnel lining formwork. At the same time, the above introduction is believed to make it easier and safer to use the tunnel lining formwork in the future.