JPS6343274Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Field of Application" The present invention relates to a concrete segment suitable for use in constructing a vertical shaft by a submerged box method, a deep foundation method, or the like.

``Prior art'' Conventionally, when constructing a shaft that reaches more than 10 meters underground, multiple arc-shaped concrete segments that are connected into a cylindrical shape are generally used, and these are constructed using the submerged box method or the deep foundation method. Ta. In the submerged box construction method, the cylindrical wall formed by connecting the above-mentioned segments etc. into a cylindrical shape is excavated and submerged, and the segments are successively stacked and connected in a cylindrical shape on top of it. becomes. On the other hand, in the deep foundation method,
This is a construction method in which a cylindrical sheet pile, which also serves as an earth retaining wall and whose lower edge is a cutting edge, is pre-sunk by pushing down using jacks, etc., and the segments are successively connected in a cylindrical shape inside the sheet pile.

``Problem that the invention aims to solve'' By the way, while the shaft being constructed is still relatively shallow, the submerged box method is considered to be better from the viewpoint of work efficiency. As the segments are piled up on the ground as the body sinks, the work to connect the segments by tightening the bolts between the joint fittings buried in the joint end faces of the segments should be done from the outside on the ground from a safety standpoint. is preferable. On the other hand, as the shaft construction becomes deeper, the cylindrical wall during construction becomes unable to sink due to large external pressure from the soil, and it becomes necessary to switch to the deep foundation construction method. It must be done inside.

However, in the case of conventional concrete segments, all of the openings for bolt tightening of joint fittings buried in the upper, lower, left and right joint end faces are used as so-called internal tightening segments that open on the inner surface of the segment. For example, when constructing a shaft like the one described above, when constructing a shaft using an external tightening segment, it is necessary to It became impossible to switch to the deep foundation method,
On the other hand, when constructing only internally tightened segments, there were problems such as segment connection work when using the submerged box construction method had to be done at high places due to the relationship with the vertical shaft.

"Means for Solving the Problem" In this invention, each joint end face, which is the upper and lower sides and the left and right sides of the arc plate-shaped segment body to constitute a cylindrical wall that is to be interconnected and sunk underground, is , in a concrete segment formed by embedding a joint fitting having a bolt operation space necessary for bolt tightening operation, the bolt operation space of the joint fitting at the joint end face of the upper side is opened to the outer surface of the segment main body, and the lower side The opening for bolt operation of the joint fitting on the joint end face of the segment body is opened to the inner surface of the segment body.

Embodiment The embodiment shown in FIG. 1 shows an example in which the present invention is applied to a concrete segment used when constructing a vertical shaft such as a water collection well. In the figure, reference numeral 1 denotes a segment main body mainly made of concrete, which is formed in the shape of an arc as a whole, and reinforcing steel materials (not shown) such as main reinforcement and distribution reinforcement are buried inside the segment body. Also,
4, which are the top and bottom sides and left and right sides of segment body 1
A plurality of joint fittings 3 are embedded in each of the joint end surfaces 2a, 2b, 2c, and 2d. Each of these joint fittings 3 is connected to an opposing joint fitting of another adjacent concrete segment using bolts and nuts, and is connected to a bolt insertion hole 3a opened on each joint end surface for bolting operation. They are each provided with a necessary bolt operation cavity 3b. In the illustrated example, the upper side of the joint end surface 2a of each bolt operation cavity 3b is
The bolt operating space 3b of each joint fitting opens on the outer surface of the segment main body 1, and the other joint end surface 2
The bolt operating spaces 3b of the joint fittings b, 2c, and 2d are configured to open on the inner surface of the segment body 1, respectively. In the figure, the concrete segment is designated as a whole by C.

Next, how to use the concrete segment C and its functions when constructing a vertical shaft such as a water collection well will be described.

For example, when constructing a vertical shaft using a plan that combines the submerged box and deep foundation methods, first of all, if the submerged box method is used, the segment C is first installed in a cylindrical sheet pile with a cutting blade 5a installed in advance as shown in Fig. 2. It is used as a segment to connect and sink one ring directly above No.5. Here, a hole 3b for bolt operation of each joint fitting on the joint end surface 2a of the upper side of the segment C
is open on the outer surface of the segment main body, so for the subsequent normal type segment to be connected to the upper stage, an external fastening segment C1, which also has a bolt operation cavity open on the outer surface, is used. In this way, the subsequent work of connecting the segments C1 to each other is performed from the ground G, which is safe.

If it becomes necessary to switch to the deep foundation method during construction, use the cylindrical sheet pile 5 as shown in Figure 3.
, excavate and push down the soil beneath it, and
A conventional inner tightening segment C2 is used for the segment to be connected to the lower stage of segment C. At this time, the bolt operating spaces 3b of each joint fitting on the joint end surface 2b of the lower side of the segment C are opened to the inner surface of the segment main body, and the inner tightening segment C2
Since they have the same structure as the above, they can be connected to each other, and therefore construction can be carried out using the deep foundation method.

In addition, in the example shown in FIG.
Although an example is shown in which the bolt operation spaces 3b of each joint fitting in c and 2d are opened on the inner surface of the segment body 1, these spaces 3b may also be opened on the outer surface of the segment body 1. no problem.

"Effects of the invention" As explained above, the concrete segment for shafts according to the invention has the bolt operation holes on the upper side of the segment body opened to the outer surface of the segment body, and the bolt operation holes on the lower side open to the outer surface of the segment body. Since the openings are made on the inner surface of the segment body, it is not only possible to smoothly switch from the submerged box construction method to the deep foundation method, but when the submerged box construction method is adopted, the segment connection work can be performed from the outside on the ground, making it safer. It has an excellent effect of improving sex.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing one embodiment of the present invention;
FIG. 3 and FIG. 3 are schematic cross-sectional views showing the construction procedure, respectively. 1... Segment body, 2a, 2b, 2c, 2
d... Joint end surface, 3... Joint fitting, 3b... Hollow space for bolt operation, C... Concrete segment.

Claims (1)

[Scope of utility model registration request] 1 Holes for bolt operation necessary for bolt tightening are provided on each joint end face, which is the upper and lower sides and left and right sides of the arc plate-shaped segment main body that is to be interconnected and constitute a cylindrical wall that is to be sunk underground. In a concrete segment in which a joint fitting provided with is buried, a hole for bolt operation of the joint fitting on the joint end surface of the upper side is opened to the outer surface of the segment body, and a hole for bolt operation of the joint metal fitting on the joint end surface of the lower side is opened to the outer surface of the segment body. A concrete segment for vertical shafts characterized by an opening on the inner surface of the segment body.