JPH0459439B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method for efficiently and economically constructing or repairing tunnels using an arch center (arch-shaped formwork for pouring lining) to which internal stress is applied through forced deformation.

[Conventional technology]

Conventionally, when constructing a new tunnel, repairing and reinforcing an aging existing tunnel that is currently closed, or renovating a tunnel to expand the cross-section of the tunnel due to double tracking or electrification, center and skin plates were used. By using integrated movable formwork or prefabricated formwork that can be repeatedly assembled and dismantled, it was possible to install shoring as desired within the tunnel. On the other hand, when repairing or renovating tunnels under live lines, it is necessary to use solid formwork that is compact and has sufficient rigidity within the construction limits to ensure space for trains and vehicles to pass through the tunnel. Because the tunnel must be lined, a special tunnel construction method is required, and a typical method is to drive tieback anchors into the ground to secure and hold the center against the load of the poured concrete. was being carried out.

[Problems to be solved by the invention]

However, with this conventional method, tieback anchors must be driven into the ground, which often causes problems with spring water, which requires a huge amount of money to stop the water, and has the risk of causing a major accident. was. Particularly in mountainous areas where mountain tunnels are constructed, most of the groundwater exists in connection with geological separation surfaces such as cracks, joints, and fracture zones that develop within the strata. The flow of water passing through the soil is faster than the flow of water passing through the gaps between the grains of the earth and sand, and is often discontinuous and localized, resulting in concentrated and sudden occurrence of spring water, so fix the center. However, the method of driving a large number of tieback anchors into the ground around the tunnel not only requires a huge amount of money to stop the spring water and take measures to prevent danger, but also has the problem of significantly delaying the construction period. Furthermore, even if there is no spring water, a large number of tieback anchors must be driven, resulting in an expensive construction method.

[Means to solve the problem]

The present inventors conducted intensive research to solve the problems of the above-mentioned conventional technology, and as a result, they utilized an arch center that maintains a predetermined shape that matches the cross section of the tunnel lining by applying internal stress through forced deformation. The above conventional problems can be completely solved by constructing or renovating a tunnel by pouring surplus concrete into the gap between the tunnel surface and the skin plate attached to the outside of the arch center along the tunnel surface. They investigated this and completed the present invention.
That is, the present invention manufactures an arch center with a radius of curvature larger than the tunnel lining cross section, and forcibly indexes both ends of this arch center to deform the outer shape into an outer shape with a smaller radius of curvature than the tunnel lining cross section. After erecting the arch at the desired location at the required intervals through a wedge in the construction tunnel so that it does not return to its original shape, the indexes at both ends are released and internal stress is applied to the arch center. A method of constructing or repairing a tunnel by fixing the arch center, then attaching a skin plate to the outside of the arch center along the tunnel surface, and sequentially pouring concrete into the gap between the tunnel surface and the skin plate. This invention relates to a tunnel construction method that uses an arch center that is subjected to internal stress due to deformation.

【Example】

Hereinafter, a tunnel construction method using an arch center to which internal stress is applied by forced deformation according to the present invention will be explained in detail based on the drawings. Figures 1 to 3 are explanatory diagrams of the construction process of the method of the present invention when an arch center is used only in the upper arch section of the tunnel lining cross section, and Figure 4 is an illustration of the construction process of the tunnel lining cross section as an arch center. An explanatory diagram of the construction state of the method of the present invention when arch centers are used in the upper arch portion and side wall portions, and FIGS. 5 and 6 are explanatory diagrams showing the shape of the wedge used to implement the method of the present invention, respectively. It is. To carry out the method of the present invention, first, as shown in FIG. 1, an arch center 1 made of H-beam steel or the like having a radius of curvature larger than the cross section of the tunnel lining is manufactured in advance in a factory, and chain blocks are attached to both ends of this arch center 1. , turnbuckles or lever blocks (hereinafter referred to as turnbuckles, etc.) 3 are attached, the arch center 1 is carried to the tunnel construction site, and both ends of the arch center 1 are forcibly pulled using the turnbuckles, etc. 3. As shown in Fig. 2, wedges 4 are placed inside the tunnel to prevent it from returning to its original shape at the desired locations and at the required intervals while the tunnel lining is deformed into a desired external shape with a radius of curvature smaller than the cross section of the tunnel lining. It is built through. When performing this construction, if the arch center 1 constitutes only the upper arch part, it is sufficient to fix the side wall centers 2 to both ends as shown in FIGS. 2 and 3.
This is not necessary if the upper arch part and the side wall part are integrally formed in advance as shown in the figure. Also, the wedge 4 used during construction is
In addition to ensuring the thickness of the concrete to be poured, when using arch center 1 and side wall center 2 when the traction at both ends of arch center 1 is released, the displacement of arch center 1 and side wall center 2 toward the ground should be avoided. Since it is used for restraint, the ground or existing tunnel lining that constitutes the tunnel surface has sufficient strength when the released traction force at both ends of the arch center 1 is transmitted through the wedge 4. In this case, a bolt with a sharp tip screwed onto the arch center 1 may be sufficient, but if the ground or existing tunnel lining does not have sufficient strength, a plate 4a may be fixed to the tip of the bolt by welding. It is sufficient to use dry packing 4b or the like which can be used to effectively transmit the load by filling the gap between the plate 4a and the ground or the existing tunnel lining. After the arch center 1 is thus erected in the construction tunnel via the wedge 4, the indexes at both ends of the arch center 1 are released by operating the turnbuckles etc. 3 that forcibly index both ends of the arch center 1. The arch center 1 is fixed in the construction tunnel via the wedge 4 with internal stress applied to the arch center 1, and then the outside of the arch center 1 and the side wall center 2 are fixed when the arch center 1 and the side wall center 2 are present. 2 along the tunnel surface on the outside of each skin plate 5.
The tunnel can be constructed or repaired by attaching the skin plate and pouring concrete into the gap 6 between the tunnel surface and the skin plate 5 one after another.

[Effect] In the tunnel construction method using the arch center 1 to which internal stress is applied through forced deformation as detailed above, the arch center 1 to which the skin plate 5 can be attached is built and fixed in the construction tunnel via the wedge 4. In this state, the indexes at both ends are released and internal reaction force is applied, so there is no need to drive tieback anchors or use shoring to reinforce the structure, resulting in a significant reduction in the number of materials used. This eliminates the need to drive numerous tieback anchors into the ground around the tunnel to secure the center, so there is no need to spend a huge amount of money to stop the spring water, or there is a risk of a major accident occurring. In addition, the construction cost is low and the construction period can be significantly shortened, and it also has the advantage of ensuring sufficient space for trains and vehicles to pass through the tunnel, especially when repairing or renovating the tunnel under active conditions. Its industrial value is extremely large.

[Brief explanation of drawings]

Figures 1 to 3 are explanatory diagrams of the construction process of the method of the present invention when an arch center is used only in the upper arch section of the tunnel lining cross section, and Figure 4 is an illustration of the construction process of the tunnel lining cross section as an arch center. An explanatory diagram of the construction state of the method of the present invention when arch centers are used in the upper arch portion and side wall portions, and FIGS. 5 and 6 are explanatory diagrams showing the shape of the wedge used to implement the method of the present invention, respectively. It is. 1... Arch center, 2... Side wall center,
3...Turnbuckle etc., 4...Wedge, 4a...
...Plate, 4b...Dry patching, 5...
Skin plate, 6... void section.

Claims (1)

[Claims] 1. An arch center with a radius of curvature larger than the cross section of the tunnel lining is manufactured, and both ends of this arch center are forcibly indexed to form an outer shape with a radius of curvature smaller than the cross section of the tunnel lining. In the deformed state, the arch center was erected at the desired location at the required intervals through a wedge in order to prevent it from returning to its original shape, and then the indexes at both ends were released to apply internal stress to the arch center. The tunnel is constructed or repaired by fixing the arch center in a fixed state, then attaching a skin plate along the tunnel surface to the outside of the arch center, and sequentially pouring concrete into the gap between the tunnel surface and the skin plate. A tunnel construction method that uses an arch center that applies internal stress through forced deformation. 2. A tunnel construction method using an arch center to which internal stress is applied by forced deformation as set forth in claim 1, in which an arch center corresponding only to the upper arch of a tunnel lining cross section is used as an arch center. 3. A tunnel construction method using an arch center to which internal stress is applied by forced deformation as set forth in claim 1, which uses an arch center corresponding to the upper arch and side wall portion of the tunnel lining cross section as the arch center. 4. An arch center to which internal stress is applied by forced deformation according to any one of claims 1 to 3, in which a chain block is used as a member for forcibly indexing both ends of the arch center. Tunnel construction method to be used. 5 Utilizing an arch center to which internal stress is applied by forced deformation according to any one of claims 1 to 3, in which a turnbuckle is used as a member for forcibly indexing both ends of the arch center. tunnel construction method. 6. An arch center to which internal stress is applied by forced deformation according to any one of claims 1 to 3, in which a lever block is used as a member for forcibly indexing both ends of the arch center. Tunnel construction method to be used.