JP3316587B2 - Plate of steel shell joint and its casting method in outer shell preceding tunnel method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an outer shell pre-tunneling method (MMST (Multi-Micro Shield Tunneling) method), i.e., excavating a plurality of single tunnels to be outer shells of the tunnels in advance. After connecting them and casting concrete into them to construct the outer shell frame and then excavating the interior to make a tunnel, the steel shells that make up the adjacent shells of the unit tunnel are fastened together The present invention relates to a shell joint plate and a casting method thereof.

[0002]

2. Description of the Prior Art FIGS.
As shown in FIG. 7, a plurality of single tunnels 31 serving as the outer shell of the tunnel are preliminarily excavated at a suitable distance by a single shield machine (not shown) having a rectangular and flat small cross section (FIG. 7).
Next, the adjacent ones of the individual tunnels 31 are connected to each other via the connecting portions 32 (see FIG. 8), and concrete 33 is poured into the individual tunnels 31 to construct the outer shell body 34. Later (see FIG. 9 and FIG. 10), outer shell body 3
Excavation and removal of the earth and sand 35 inside 4 (see FIG. 10),
Thereafter, an inner member 36 such as an inner wall, an intermediate floor slab, and a partition is constructed inside the outer shell body 34 to form a tunnel (FIG. 1).
1) This is the construction method. In this method, the single tunnel 31 has a rectangular short-angle cylindrical shape (2.5 m in length, 7 to 7.5 m in width).
(m, 1.2 mm in depth) in the excavation direction of a single shield machine.
As shown in FIGS. 12 and 13, a plurality of main girders 38 in the form of rectangular loops made of steel molds are connected at equal intervals by a large number of connecting plates 39, and a formwork is formed when concrete 33 is poured. As shown, the outer periphery is formed by covering with a skin plate 40, and is composed of a plurality of segments that can be automatically assembled by an erector of a single shield machine. FIG.
In 2, reference numeral 41 denotes a center pillar provided on each main girder 38. The connecting portion 32 connecting the steel shells 37 constituting the adjacent unit tunnel 31 is not shown, but the steel shell 37 is not shown.
After connecting them with steel shell joints, applying a precedent retaining and water stoppage auxiliary chemical injection around the joints, installing a shoring to remove the earth and sand between the joints, and then arranging the reinforcing bars at the joints It is straightened and cast concrete. On the other hand, in the case of a steel shell joint, a plurality of semi-concave spherical washers and a washer having a smaller diameter are used for each washer in order to allow a displacement of an adjacent steel shell (a state in which a fastening portion does not face directly). A rectangular flat plate having a truncated cone-shaped bolt hole opened at the bottom of the steel plate and welded to a fastening portion of an adjacent steel shell, and a hemisphere slidably engaged with each washer seat. A body washer, a washer engaged with each washer seat of a plate welded and joined to an adjacent steel shell, a joint bolt inserted into each bolt hole, and a nut screwed to both ends of each joint bolt The following are being studied.

[0003] Conventionally, as the plate of the steel shell joint,
A material having a hardness substantially equal to that of the washer is used.

[0004]

However, in the steel shell joint plate in the conventional outer shell preceding tunneling method, since the hardness of the plate is almost equal to the hardness of the washer, there is a difference in the spherical shape between the washer and the washer. In some cases, there is a problem that a one-side contact occurs at the time of fastening, and the washer is deformed after the fastening due to deformation of the washer and the washer in the one-side contact state due to an external force. Therefore, an object of the present invention is to provide a steel shell joint plate and a casting method for the outer shell preceding tunneling method without loosening after fastening.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, the steel shells constituting the unitary tunnels adjacent to each other in the plate outer shell advanced tunneling method of the steel shell joint in the outer shell advanced tunneling method of the present invention are hemispherical. In order to fasten through the washer, the joint bolt and the nut, a plurality of semi-concave spherical washer and a truncated conical bolt hole having a small diameter on the side of the washer and opened at the bottom of each washer are provided. And a plate joined to a fastening portion of an adjacent steel shell, wherein the hardness of at least the washer is different from that of the washer. Further, in the method of casting a plate of a steel shell joint in the outer shell leading tunnel method, steel shells constituting adjacent unit tunnels in the outer shell leading tunnel method are fastened to each other through hemispherical washers, joint bolts and nuts. Therefore, a plurality of semi-concave spherical washer and a truncated conical bolt hole opened at the bottom of each washer with a small diameter on the side of the washer,
When casting a plate to be joined to the fastening portion of the adjacent steel shell, iron sand is mixed into a core made of molding sand forming at least each washer. The mixing amount of the iron sand is preferably 5 to 40 wt%.

[0006] By making the hardness of at least the washer of the plate different from that of the washer, even if there is a difference in the spherical shape between the washer and the washer, either the washer or the washer is required when the steel shells are fastened by the steel shell joint. The one with lower hardness is deformed, and the one-side contact of both is eliminated. Hardness of at least washer bearing plate may be higher than that of the washer (e.g., the plates were formed of cast steel SCW480 such hardness of H _B 230 to 280, and the washer hardness of H _B 160 to 200 S25C, etc. It is preferable that the hardness of at least the washer of the plate is lower than that of the washer.

By mixing iron sand into a core made of molding sand forming at least each washer, the iron iron functions as a cooling metal, and the solidification of the molten metal in the peripheral portion of the core becomes faster and the structure becomes denser. Become. If the iron sand content is less than 5 wt%,
It does not function as a chill, while if it exceeds 40 wt%,
It no longer functions as a core. The preferred amount of iron sand is
10 to 30% by weight.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1, 2, 3 and 4
1 is a plan view showing an example of an embodiment of a steel shell joint plate in an outer shell preceding tunnel method according to the present invention, a sectional view taken along line II-II in FIG. 1, and a sectional view taken along line III-III in FIG. FIG. 4 is a sectional view taken along line IV-IV in FIG. 1.
The plate 1 is made of cast steel such as SCW480, and is provided with a plurality of semi-concave spherical washer seats 3 on one surface (the upper surface in FIGS. 2 to 4) of a rectangular flat plate body 2. 2, a frusto-conical bolt hole 4 is formed on one side, that is, on the bottom of each washer 3 with a small diameter on the washer 3 side, while the plate body 2 on the washer 3 side will be described later. A plurality of welded portions 5 each having a linear protruding edge are provided at a joint portion with the steel shell, and a base portion of each welded portion 5, that is, a joint portion between the welded portion 5 and the plate body 2 is formed in a round shape. And the washer 3 of the plate body 2
On the side, a peripheral portion of each washer 3 and the bolt hole 4 is left in a cylindrical shape, and a rib 6 is formed so as to linearly extend therefrom. the hardness of the peripheral surface portion of the hole 4 and H _B 230 to 280,
It is set higher than the hardness of the plate body 2 (H _B 160~200). In the drawing, reference numeral 7 denotes a groove formed at the end of the welded portion 5.

In order to manufacture the plate 1, as shown in FIG.
In a sand mold 8 forming ribs 6 and 5 to 40 wt% of iron sand mixed with casting sand, a plurality of cores 9 forming washer seats 3 and bolt holes 4 are placed, and cast steel such as SCW480 is placed. After injecting a molten metal and performing mold release, post-processing is performed. During the casting, the molten metal of the peripheral portion of the core 9 is cooled by sand which functions as a chill, tissue becomes dense coagulation than the other portions becomes faster, hardness H _B 230
Up to 280.

The above-mentioned plate 1, a steel shell joint 13 having a hemispherical washer 10 made of structural carbon steel such as S25C, a joint bolt 11 and a nut 12 (see FIG. 6), A plurality of main girders 14 in the form of rectangular loops made of steel are connected at equal intervals by a large number of connecting plates 15, and the outer periphery is skinned so as to constitute a formwork during concrete casting for the outer shell frame. In order to fasten the rectangular short-square tubular steel shells 18 covered with the plate 16 and provided with a plurality of ribs 17 (only one is shown in FIG. 6) at the fastening portion, first, The plate 1 is attached to the fastening portion of each steel shell 18 by the rib 1
7 and the welded portion 5 are joined by welding. In this joining, the welding portion 5 is provided on the plate 1 and the weight is reduced by the lightening process, so that the welding joining operation is easily performed.

Next, a washer 10 is engaged with each washer 3 of each plate 1 of the steel shell 18 which is appropriately separated and adjacently constructed, and a coupling bolt 11 is fitted into each washer 10 and the bolt hole 4. Is inserted, nuts 12 are screwed into both ends of each joint bolt 11 and tightened. With the tightening of each nut 12, washer seat 3 and the washer even if there is a difference in 10 of spherical shape, tightening low hardness washer 10 by the fastening force by the nut 12 (H _B 160 to 200)
Is deformed and adapted to the washer 3 to eliminate the one-sided contact, and does not loosen after fastening.

[0012]

As described above, according to the plate of the steel shell joint in the outer shell preceding tunnel method of the present invention, even if there is a difference in the spherical shape between the washer and the washer, the steel shell formed by the steel shell joint can be used. When fastening each other, either the washer or the washer with the lower hardness is deformed and the one-side contact of both is eliminated,
There is no loosening after fastening. In addition, according to the method of casting a plate of a steel shell joint in the outer shell preceding tunnel method, at least by mixing iron sand into a core made of molding sand forming each washer, the iron sand functions as a cooling metal, Since the solidification of the molten metal in the peripheral portion of the core becomes faster and the structure becomes denser, at least the hardness of each washer can be made higher than that of the washer.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of an embodiment of a plate of a steel shell joint in an outer shell preceding tunnel method according to the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a sectional view of a main part showing an example of an embodiment of a method of casting a plate of a steel shell joint in the outer shell leading tunnel method according to the present invention.

FIG. 6 is a cross-sectional view of a steel shell joint portion including a steel shell joint plate provided with a steel shell joint plate in the outer shell preceding tunnel method according to the present invention.

FIG. 7 is an explanatory view of a first step of the outer shell preceding tunnel method.

FIG. 8 is an explanatory diagram of a second step of the outer shell preceding tunnel method.

FIG. 9 is an explanatory view of a third step of the outer shell preceding tunnel construction method.

FIG. 10 is an explanatory view of a fourth step of the outer shell preceding tunnel method.

FIG. 11 is an explanatory view of a fifth step of the outer shell preceding tunnel method.

FIG. 12 is a front view of a steel shell used for the outer shell preceding tunnel method.

FIG. 13 is an enlarged sectional view taken along line XIII-XIII in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate main body 3 Washer washer 4 Bolt hole 8 Sand mold 9 Core 10 Washer 11 Joint bolt 12 Nut 18 Steel shell

Continuing from the front page (72) Inventor: Jun Saito 1780, Kamikono, Yachiyo-shi, Chiba Kawasaki Heavy Industries, Ltd.Yachiyo Factory (72) Inventor Taku Hirai 8-21-1, Ginza, Chuo-ku, Tokyo Japan Incorporated Takenaka Civil Engineering Co., Ltd. (72) Inventor Shigeki Nomura 8-21-1, Ginza, Ginza, Chuo-ku, Tokyo Tokyo Public Works Co., Ltd. (72) Invention Tadahiro Fukumoto 8-21-1, Ginza, Chuo-ku, Tokyo, Japan (72) Inventor Chinobu Nobuaki 8-21-1, Ginza, Chuo-ku, Tokyo Co., Ltd.Tokuhiro Takenaka, Ltd. (72) Toshiaki Sugiyama, Tokyo 8-21-1, Ginza, Chuo-ku, Tokyo Takenaka Civil Engineering Co., Ltd. (56) References JP-A-10-331595 (JP, A) JP-A-11-44193 (JP, A) JP-A-2000-1445397 (JP, A) JP-A-52-26977 (JP, A) JP-A-5-24132 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21D 11/14 E21D 13/00 F16B 5/02

Claims (3)

(57) [Claims] 1. A plurality of semi-concave spherical washer and washer for fastening steel shells constituting adjacent unitary tunnels in the outer shell preceding tunnel method via hemispherical washers, joint bolts and nuts. A plate having a truncated cone-shaped bolt hole opened at the bottom of each washer with a small diameter on the seat side and joined to a fastening portion of an adjacent steel shell, wherein the hardness of at least the washer is reduced. A steel shell joint plate in the outer shell precedence tunneling method, which is different from that of the washer. 2. A plurality of semi-concave spherical washer and washer for fastening steel shells constituting adjacent single tunnels in the outer shell preceding tunnel method via hemispherical washers, joint bolts and nuts. It has a truncated conical bolt hole that opens at the bottom of each washer with a small diameter on the seat side, and at least each washer is formed when casting a plate to be joined to the fastening part of the adjacent steel shell. A method for casting a plate of a steel shell joint in an outer shell preceding tunneling method, wherein iron sand is mixed into a core made of casting sand. 3. The method for casting a plate of a steel shell joint in the outer shell preceding plate method according to claim 2, wherein the mixed amount of the iron sand is 5 to 40 wt%.