JPS6257796B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pneumatic shield construction method characterized by the method of installing material locks.

In the conventional pneumatic shield construction method, the material lock is installed on the atmospheric side of the tunnel, but because it is difficult to relocate the bulkhead, the material lock must be placed in the final setup extension state from the beginning, as shown in Figure 1. Not only that, but it is necessary to inject chemicals over a long distance for initial excavation, and to apply pressure to the shaft.
In addition, when transitioning to main excavation, it is necessary to relocate the bulkhead and change the setup of the pneumatic facilities, so there are disadvantages such as the inability to smoothly transition from the initial excavation to the main excavation, and too much economic and time loss in the pneumatic work. It was hot.

This invention was devised to solve the above-mentioned conventional problems, and its purpose is to complete initial excavation with a minimum amount of chemical injection, etc., and smoothly transition to main excavation without changing the pressure equipment. The purpose of the present invention is to provide a pneumatic shield construction method that can

This invention will be explained below with reference to FIGS. 2 to 6. Figure 2 shows an overview of the initial excavation period corresponding to Figure 1. First, a horizontal cylindrical material lock 4 formed by connecting end locks 2 and 3, each having an entrance/exit with an airtight door 1, is fixed to the bulkhead 5 at the end of the end lock 2 on the entrance/exit side, and is placed inside the tunnel 6. Install it on the pressure side. Then, initial excavation is performed using a shield while applying pressure inside the tunnel 6.

After the initial excavation is completed, the constituent members that will become the intermediate lock 8 of vertical quarter structure when connected and assembled in the circumferential direction are carried through the material lock 4 to the pressure side, and
As shown in the figure, while assembling the intermediate lock 8, the end lock 3 is disconnected and separated from the end lock 2, and then the intermediate lock 8 is installed between the end locks 2, 3, and these locks 2, 3, Connect 8. The main excavation is started using the material lock 4' thus obtained. Intermediate lock 8 is added in the same manner as above as the main excavation progresses, and the main excavation is continued using the material lock 4'' obtained in this way. No. 6
Figures A, B, and C show enlarged views of the front, left and right sides of this material lock 4''.

The end lock 2 is equipped with an airtight door 1 at the end on the entrance/exit side, as well as a pressure gauge and an internal pressure adjustment device for determining the pressure inside the lock and the tunnel.
A rail 9 is laid on the inner bottom. Also,
The end lock 3 has an airtight door 1 and a rail 10 on the inner bottom. These end locks 2, 3 are connected by bolts of inward flanges provided at the ends in the tunnel direction, so that the rails 9, 10 can be made continuous.

As mentioned above, the intermediate lock 8 has a vertical quarter structure and is assembled by bolting the inward flanges provided at the circumferential ends of the top plate 11, left and right side plates 12, and bottom plate 13. The end of each plate in the tunnel direction has an inward flange for connecting to the end locks 2 and 3, and the bottom plate 13 has an inward flange for connecting to the end locks 2 and 3, and is connected to the rails 9 and 10 when connected to the end locks 2 and 3. It is equipped with a water rail 14. The reason why this intermediate lock 8 has a vertical quarter structure is to carry it into the pressure side through the entrance and exit of the end lock 2.
This is also to facilitate assembly on the pressure side.

As described above, this invention installs a horizontal cylindrical lock that can be divided into two in the tunnel direction on the pressure side in a tunnel, divides this lock as it excavates, and installs an intermediate lock assembled on the pressure side in the middle. Since the construction is such that additions are made, it is possible to transition to the main excavation more smoothly than the initial excavation without having to change the structure of the bulkhead relocation and isobaric facilities. Therefore, for initial excavation, the lock needs to be as short as necessary, and the chemical solution can be injected in the shortest section.
Furthermore, pressure work is also easy. Therefore, the economic and time losses associated with pressurized air work are drastically reduced compared to the conventional method, and it is possible to improve the efficiency of shield construction.

In addition, since the additional intermediate lock has a vertically divided structure and is assembled by being carried to the pressure side through the existing lock, it is easy to extend the lock on the pressure side.
This method can be reliably used and the locking function can be ensured even during the transition from initial excavation to main excavation, so by adopting such an intermediate lock, the practical use of this invention method becomes more reliable.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing the situation during initial excavation using the conventional method, and Figures 2, 3, and 4 show the transition from initial excavation to main excavation and the situation during main excavation using this invention method. 5 is a schematic perspective view of the intermediate lock, and FIG. 6 is an enlarged view of the material lock in FIG. 4, with A being a front view and B and C being left and right side views. 1... Airtight door, 2, 3... End lock, 4,
4', 4''...Material lock, 5...Bulkhead,
6...Tunnel, 7...Shield, 8...Intermediate lock, 9, 10...Rail, 11...Top plate, 1
2...Side plate, 13...Bottom plate, 14...Rail.

Claims (1)

[Claims] 1 After initial excavation by installing a horizontal cylindrical material lock that can be divided into two in the tunnel direction on the pressure side in the tunnel, the material lock is divided and a vertically divided cylindrical intermediate lock is assembled and added in the middle. This is a pneumatic shield construction method that is characterized by carrying out the main excavation.