JPH0439355Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to a formwork device for lining shield tunnels, and more specifically, forms lining walls using cast-in-place concrete as the shield machine advances. This invention relates to formwork equipment used in construction methods.

(Prior Art) The applicant of this invention previously disclosed in Japanese Patent Application No. 61-176194 (Japanese Unexamined Patent Publication No. 63-32096) that a plurality of molds were formed into a ring shape inside the tail portion of a shielding machine. In this method, concrete is cast between the formwork and the tail part to form a primary lining wall on the inner surface of the tunnel as the shield machine moves forward. We proposed a shield tunnel lining method in which the shoring is removably installed in advance and left on the primary lining wall surface when the formwork is removed after the concrete has hardened.

This construction method leaves the shoring installed in advance on the primary lining wall when the formwork is removed, so the primary lining wall can be kept in a stable state by the shoring at the same time as the formwork is removed. Furthermore, since the process of assembling the shoring alone can be omitted, there is an advantage that the entire process is shortened.

By the way, the formwork used in this construction method has a groove that opens outward and extends along the circumferential direction of the tunnel at approximately the center of its outer circumferential surface, and within this groove, the shoring is placed between the outer circumferential surface and the formwork. The shoring is inserted and installed so that the outer circumferential surface of the groove is substantially flush with the outer circumferential surface of the groove, and the shoring is removably fixed to the circumferential wall of the groove.

(Problem to be solved by the invention) Ideally, the width of the opening of the groove and the width of the shoring should be approximately the same, so that there is no gap between the two. This requires extremely high machining accuracy, and even if this were done, it would be difficult to insert and install the shoring. Therefore, in order to facilitate the work, it is inevitable that a gap will be formed between the periphery of the opening of the groove and the shoring, and it is therefore necessary to prevent the poured concrete from leaking through the gap.

This invention was made based on the above-mentioned background, and the purpose is to provide a formwork that can reliably suppress leakage of poured concrete.

(Means for Solving the Problems) This invention for achieving the above object is characterized in that the gap between the opening periphery of the groove and the support is closed by a packing member.

(Example) As shown in FIGS. 1 to 3, the formwork 1 is divided into a plurality of segments in the circumferential direction of the tunnel, and this formwork 1 has a ring shape inside the tail part 21 of the shielding machine. is assembled, and concrete is forced and placed between the formwork 1 and the tail part 21 from a supply port (not shown) provided in the end frame ring 22,
The primary lining wall 23 is sequentially formed as the shield machine advances. At this time, the poured concrete is pressed by the pressing jack 24 via the end frame ring 22 and brought into close contact with the ground 25.

The formwork 1 has an outer circumferential plate 2 that is curved along the circumferential direction of the tunnel and serves as a concrete pouring surface, and an inner circumferential plate 4 that is connected to the outer circumferential plate 2 via a pair of ribs 3. An opening 5 extending along the circumferential direction of the tunnel is formed in the plate 2, thereby forming a groove 6 having the rib 3 as a side wall and the inner peripheral plate 4 as a bottom wall.

A shoring 7 made of H-beam steel is inserted into the groove 6, and like the formwork 1, this shoring 7 is divided into a plurality of segments in the circumferential direction of the tunnel, and one flange part 7a is divided into a plurality of segments. It is removably fixed to the bottom wall of the groove 6, that is, the inner peripheral plate 4, by bolts and nuts 8. The outer peripheral surface of the other flange portion 7b and the outer peripheral surface of the outer peripheral plate 2 are located on the same peripheral surface.

A pair of side plates 9 along the circumferential direction of the tunnel and a pair of side plates 10 along the axial direction of the tunnel are provided on the peripheral edge of the outer circumferential plate 2, and when the formwork 1 is assembled, the side plates 9 are arranged adjacent to each other in the axial direction. The formworks 1 are connected to each other by bolts and nuts 11 on the side plates 9 (first
), the formworks 1 adjacent to each other in the circumferential direction are connected by bolts and nuts 12 at the side plates 10 (FIG. 2), and the supporting structures 7 adjacent to each other in the circumferential direction are connected by joint plates 13. (Figures 2 and 3).

In the formwork device described above, a gap is formed between the periphery of the opening 5 of the groove 6 and the flange 7b of the shoring 7, so if left as is, the poured concrete will leak from the gap. A packing member that prevents this concrete from leaking is shown in the drawings from FIG. 4 onwards.

In the example shown in FIG.
4 is provided, a plate-shaped packing member 15 is placed on this stepped portion 14, and one flange portion 7a of the shoring 7 is
The packing member 15 is sandwiched between the flange portion 7b and the stepped portion 14 by making the width of the other flange portion 7b larger than that of the other flange portion 7b.

In the example shown in FIGS. 5a and 5b, a plate-shaped packing member 16 having a width larger than that of the stepped portion is fixed to the stepped portion 14, and the state shown in FIG. 5 a changes from the state shown in FIG. 5 b. When the shoring 7 is inserted into the groove 6, the packing member 16 is bent inward by the flange portion 7b, and the gap is filled with this bent portion.

In the example shown in FIG. 6, a wedge-shaped packing member 17 is filled between the flange portion 7b and the peripheral edge of the opening 5.

The packing members 15, 16, and 17 are all made of an elastic material such as rubber.

Furthermore, in the example shown in FIGS. 7 and 8, the packing member is composed of an elastic tube 18 made of rubber or the like, and this elastic tube 18 is placed in advance between the flanges 7a and 7b of the shoring 7, and the shoring 7 is placed in the groove 6. After insertion and installation, pressurized air is supplied from the injection port 20 into the elastic tube 18 to expand it, thereby filling the gap.

After the concrete of the primary lining wall 23 has hardened, demolding is performed. At this time, the bolts and nuts 8 are removed, only the formwork 1 is removed from the primary lining wall 23, and the shoring 7 is removed from the primary lining wall 23. will be left behind.

(Effects of the invention) As described above, according to this invention, since the space between the shoring inserted and installed in the groove formed in the formwork and the opening periphery of the groove is closed by the packing member, To prevent poured concrete from leaking, construction can be carried out safely, and a high-quality lining wall can be formed.

[Brief explanation of the drawing]

FIG. 1 is an axial sectional view of a tunnel showing an embodiment of the invention, FIG. 2 is a view taken along the line - of FIG. 1, and FIG. 3 is a sectional view taken along the line - of FIG. 1. FIG. 4 is a sectional view showing an example of a packing member,
5a and 5b are sectional views showing another example of the packing member, FIG. 6 is a sectional view showing still another example of the packing member, and FIG. 7 is a sectional view showing still another example of the packing member, FIG. 8 is a sectional view taken along the line - in FIG. 7. 1... Formwork, 2... Outer peripheral plate, 3... Rib, 4...
... Inner peripheral plate, 5 ... Opening, 6 ... Groove, 7 ... Shoring, 9, 10 ... Side plate, 14 ... Step, 15, 1
6, 17, 18...Packing members.

Claims (1)

[Scope of utility model registration request] A groove extending along the circumferential direction of the tunnel and opening outward is formed at approximately the center of the outer circumferential surface of the formwork that curves along the circumferential direction of the tunnel, and the shoring is placed within this groove along the outer circumferential surface. It is inserted and installed so that the outer peripheral surface of the formwork is located on almost the same peripheral surface, and this support is removably fixed to the peripheral wall of the groove, and the gap between this support and the opening periphery of the groove is a packing member. A formwork device for lining a shield tunnel, which is characterized in that it is closed in a twisted manner.