JP2541845Y2 - Concrete box for underground structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete box used in an open shield method.

[0002]

2. Description of the Related Art Among the construction methods of underground structures such as laid underpasses such as water and sewage, common ditch, telegraph, telephone, etc. in an urban area,
The open shield method is known as a highly rational method utilizing the advantages of the open cutting method (open method) and the shield method.

FIG. 5 schematically shows an open shield machine 1, which is a U-shaped shield machine having left and right side wall plates 1a and a bottom plate 1c connecting between them, and having open front and rear end faces and an upper surface. is there. In the open shield machine 1, the propulsion jacks 2 are arranged side by side vertically toward the rear. 3 in the figure
Indicates a partition provided in the shield machine 1.

[0004] Earth and sand are excavated from the front or upper surface of the shield machine 1 by excavating means 12 such as a shovel, auger, and bucket.
And excavate. The pushing angle 8 of the frame made of steel is brought into contact with the front end of the existing underground structure by the concrete box 4, the propulsion jack 2 is extended, and the shield machine 1 is advanced. Then, the propulsion jack 2 is contracted and the push angle 8 is adjusted to the tail portion 1c.
And a new concrete box 4 is hung from above in the tail part 1d, and the bottom is supported by a height adjusting member 7 arranged at appropriate intervals on the bottom plate 1b. Set at the forefront of the underground structure.

[0005] Then, the propulsion jack 2 is slightly extended and the pushing angle 8 is applied to the front end face of the concrete box 4, and the grout material 6 is injected into the gap between the concrete box 4 and the shield machine 1 from the ground. Next, the propulsion jack 2 is extended and the shield machine 1 is pushed forward to set a new concrete box 4 in the tail portion 1c. When the shield machine 1 moves forward in this way, the concrete box 4 in the portion grouted with the grout material 6 comes out backward from the tail portion 1c of the shield machine 1 and remains in the ground, and the concrete boxes 4 are sequentially cascaded. The underground structure is buried in the ground to form an underground structure, a backfill 5 is applied on the underground structure behind, and when the open shield machine 1 reaches the reaching pit, it is removed and the construction is completed. .

[0006] By the above-mentioned open shield method, the concrete box 4 is attached to the tail part 1 of the shield machine 1.
It is necessary to connect to the concrete box 4 already installed when it is hung in c. This concrete box 4
As a method for connecting them, a box culvert joint as disclosed in Japanese Utility Model Laid-Open No. 49-45110 can be used.

FIG. 4 shows the details thereof. In the figure, reference numeral 11 denotes a bolt hole, which is located at each corner of the concrete box 4, in a direction perpendicular to the end face 12 of the concrete box 4, and the total length of the bolt 13. Is provided at a predetermined length capable of storing. Reference numeral 14 denotes a groove that opens into the concrete box 4 and communicates with the bolt hole 11. The groove is provided at an intermediate position that divides the length of the bolt hole 11 into approximately two portions, and is substantially perpendicular to the bolt hole 11.

In this manner, the bolt 13 is stored in the bolt hole 11 of the concrete box 4 as shown by a chain line in FIG. 4 until the bolt 13 is suspended in the tail portion 1c of the shield machine 1. In connecting the four,
The bolt 13 is pulled out from the bolt hole 11 in the direction of the arrow, inserted into the bolt hole 11 of the opposing concrete box 4, and the tip of the bolt 13 is pulled out to the groove 14 provided in the opposing concrete box 4. Thereafter, the nuts 15 are screwed into the two ends of the bolts 13 from the grooves 14 of the concrete box 4 and tightened. By performing such operations for the four corners of each concrete box 4, the connection work between the concrete boxes 4 is completed.

[0009]

[Problem to be Solved by the Invention] The bolt hole 11 and the groove 14
Are provided at the four opposite corners of the front and rear end faces of the concrete box 4, respectively, but both ends of the bolt 13 and the nut
In order to prevent corrosion of 15 and prevent water leakage from the bolt holes 11, the grooves 14 are filled with mortar after filling to fill them.

However, in the joint as disclosed in Japanese Utility Model Application Laid-Open No. 49-45110, the lower groove 14 of the concrete box 4 opens upward inside the concrete box 4, so that the mortar to be filled therein may fall. However, the groove 14 at the bottom of the concrete box 4 opens downward, so it is necessary to take measures to prevent it from falling when filling the mortar. Extremely troublesome measures such as applying a plate are required.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned disadvantages of the prior art, and to provide a concrete for underground structures in which a concave portion for fixing the ends of bolts for joining the boxes with a nut or the like can be easily filled with mortar. To provide a box.

[0012]

According to the present invention, in order to achieve the above object, at each corner of the front and rear end faces of a concrete box,
A bolt hole is provided substantially perpendicular to the end face, and a concave portion which opens upward into the box at the lower part of the concrete box and which communicates with the bolt hole is opened upwardly outside the box at the upper part of the concrete box. The gist of the present invention is to provide a recess for conducting to the bolt hole, and to provide the recess at a substantially middle position of the length of the bolt hole.

[Action]

According to the first aspect of the present invention, a bolt is inserted into a bolt hole of a concrete box, and nuts are respectively screwed into recesses of the concrete box into both ends of the bolt to be tightened. After that, the mortar is filled in the recess, but the recess provided at the four corners of the concrete box opens upward in the lower part of the concrete box and upwards in the upper part of the concrete box. Since the mortar is opened and all the concave portions are opened upward as described above, the filled mortar does not fall without any special measures.

According to the second aspect of the present invention, in addition to the above operation, the bolts are stored in the bolt holes of the concrete box, and when connecting the concrete boxes, the bolts are pulled out from the bolt holes. A relatively long bolt can be easily set in the bolt hole by inserting it into the bolt hole of the opposing concrete box and pulling out the tip of the bolt to the recess provided in the opposing concrete box.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. 1 is a vertical sectional side view showing an embodiment of a concrete box for underground structures of the present invention, FIG. 2 is an external perspective view of the same, FIG. 3 is a vertical sectional side view before joining, and shows the conventional example. The same components as in FIG. 4 are denoted by the same reference numerals.

As in the prior art, the concrete box 4 is provided with bolt holes 11 at respective corners of the front and rear end faces 12 and at a right angle to the end face 12 as shown in FIG. .

Further, at the lower left and right sides of the concrete box 4, the center of the bolt hole 11 is located substantially in the middle of the length of the bolt hole 11, that is, substantially at the center of the concrete box 4. And a concave portion 16 which is open to the bolt hole 11 and is electrically connected to the bolt hole 11.

On the left and right of the upper part of the concrete box 4, an opening is formed upwardly outwardly of the concrete box 4 at a substantially middle position of the length of the bolt hole 11, that is, at a substantially center position of the concrete box 4. In addition, a concave portion 17 that is electrically connected to the bolt hole 11 is provided. These concave portions 16 and concave portions 17 can be formed by a box forming method when the concrete box 4 is manufactured, and the bolt holes 11 can be formed by embedding a sheath.

As described above, the concrete box 4 is suspended in the tail portion 1c of the shield machine 1 as shown in FIG. 5 for use in the open shield method.
Then, as shown in FIG. 3, a bolt 13 as a connecting member is stored in the bolt hole 11 of the concrete box 4, and the already installed concrete box 4 and the newly suspended concrete box 4 are connected to each other. In doing so, the bolt 13 is pulled out from the bolt hole 11 in the direction of the arrow, inserted into the bolt hole 11 of the existing concrete box 4, and the tip of the bolt 13 is pulled out to the concave portion 16 or the concave portion 17 provided in the existing concrete box 4. After that, the nuts 15 are screwed from the concave portions 16 and the concave portions 17 of the concrete box 4 into both ends of the bolts 13 and tightened. It is to be noted that the work is performed from the outside on the upper surface of the concrete box 4 for the concave portion 17, and the work is performed inside the concrete box 4 for the concave portion 16.

By performing such operations on the four corners of each concrete box 4, the connection work between the concrete boxes 4 is completed. After the connection, as shown in FIG. The mortar 18 is filled, and the mortar 18 fills the recess 16 and the recess 17. For the filling operation of the mortar 18, the concrete box 4
Is performed from the outside on the upper surface of.

As another embodiment, the bolt hole 11 may be relatively short, and the concave portion 16 or the concave portion 17 may be provided at the end of the bolt hole 11. In this case, since the bolt 13 is also shorter in accordance with the length of the bolt hole 11, if the recess 16 or the recess 17 is wider than the bolt 13, the concrete boxes 4 must be opposed to each other. The bolt 13 can be inserted into the bolt hole 11 directly from the recess 16 or 17 to perform the joining.

[0022]

[Effects of the Invention] As described above, the concrete box for underground structures of the present invention uses bolts and nuts when joining the boxes to prevent detachment, uneven settlement or floating. Although the mortar is filled with the mortar after the joining, the mortar can be easily filled without fear of falling.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing one embodiment of a concrete box for an underground structure of the present invention.

FIG. 2 is an external perspective view showing one embodiment of a concrete box for an underground structure of the present invention.

FIG. 3 is a longitudinal side view before joining.

FIG. 4 is a vertical sectional side view showing a conventional example.

FIG. 5 is a vertical sectional side view schematically showing an open shield method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Open shield machine 1a ... Side wall plate 1b ... Bottom plate 1c ... Tail part 2 ... Propulsion jack 3 ... Partition wall 4 ... Concrete box 5 ... Backfilling 6 ... Grout material 7 ... Height adjustment material 8 ... Pushing material 9 ... Excavation means 11 ... bolt hole 12 ... end face 13 ... bolt 14 ... groove 15 ... nut 16 ... recess 17 ... recess 18 ... mortar

Claims (2)

(57) [Scope of request for utility model registration] 1. A bolt hole is provided at each corner of the front and rear end faces of a concrete box at a substantially right angle to the end face, and a lower part of the concrete box is opened upward into the box and communicates with the bolt hole. A concrete box for an underground structure, characterized in that a concave portion to be opened upwards outward of the container at an upper portion of the concrete box, and a concave portion is provided to communicate with the bolt hole. 2. The concrete box for an underground structure according to claim 1, wherein the concave portion is provided at a substantially middle position of the length of the bolt hole.