JP2614287B2 - Method of constructing cylindrical structure and steel segment for construction - Google Patents

Description

The present invention relates to a method for constructing a cylindrical structure such as a deep foundation pile, an underground space, a water storage tank, and a steel segment for construction in the civil engineering and construction fields.

(Prior Art) As is well known, steel segments are used as temporary members when constructing concrete structures, and many types have been developed.

Thus, in the method of constructing a cylindrical structure such as a deep foundation pile, an underground space, a water storage tank, in many cases, the steel segments are joined to form an annular segment wall, and then the steel segments are removed. Instead, concrete burying means is employed. However, despite the large amount of steel material, the mechanical strength is low, which is extremely uneconomical.

Therefore, Japanese Patent Application Laid-Open No. 63-595 discloses that a strong annular wall is formed as a structure by connecting steel segments by connecting bolts between steel segments and connecting upper and lower steel segments using a connecting material. There has been proposed a method (hereinafter referred to as "A invention") of constructing an economical pile having a small number of inserted reinforcing bars, high rigidity, and economic efficiency.

(Problems to be Solved by the Invention) The present inventors have developed a vertical pile using steel segments and then developed a landslide prevention steel pipe anti-construction method in which steel sheet piles are inserted as reinforcing bars. In order to increase the rigidity of the annular segment wall itself made of steel segments, we studied a method of suppressing landslides by reducing the rebar material, making it more durable and more economical. It was found that the joint was weak and could not be used for applications where large horizontal force, bending and shearing force acts like a landslide prevention steel pipe pile.

The invention A is also stronger than the conventional steel segment, but remains uneasy when a large bending or shearing force is applied.

An object of the present invention is to provide a method for constructing a cylindrical structure, which is highly reliable in structural mechanics, and which is economically advantageous. It is to provide an excellent construction steel segment.

(Means for Solving the Problems) The present invention provides the following means (a) to (e) as means for solving the above problems and achieving the object. (A) A skin curved to a set curvature A steel segment consisting of a plate and a grid-like rib having a friction welding joint provided with a through hole for bolt welding at the circumferential and vertical ends welded to the inner peripheral surface of the skin plate. After constructing an annular segment wall on the peripheral surface of the cylindrical excavation hole while friction-joining via, a cylinder for filling concrete between the outside of the annular segment wall and the cylindrical excavation hole and the inner hole of the annular segment wall Structure construction method.

b. The method for constructing a cylindrical structure according to item a), wherein a steel segment having a skirt metal fitting for closing a gap is provided on an outer surface on a connection side of the skin plate.

c. The method for constructing a cylindrical structure according to the above item a), wherein a steel segment provided with a grid-like rib having a warped lateral rib is used.

d, a cylindrical structure comprising a skin plate curved to a set curvature, and a grid-like rib formed on the inside of the skin plate and formed with a joint for friction welding having a through hole for bolt welding at an end. Steel segment for building objects.

e, a skin plate curved to a set curvature, a grid-like rib formed inside the skin plate and formed with a joint for frictional bonding provided with a through hole for bolt bonding at an end, and the skin plate. And a skirt fitting for closing a gap provided on the outer surface on the connection side of the steel segment.

(Operation) The method according to the present invention is characterized in that after drilling a desired cylindrical drilling hole, the skin plate curved to the set curvature and the circumferential and vertical ends welded to the inner circumferential surface of the skin plate are bolted to each other. A steel segment consisting of a grid-like rib having a frictional joint having a through hole is friction-joined through a successive attachment plate, and an annular segment is formed on an annular cylindrical excavation hole peripheral surface covering the excavation hole peripheral surface. Since the wall is constructed, the annular segment wall has an extremely strong joint portion and can be handled as a two-way material, and can be economically designed as a rebar material that can withstand various stresses.

Moreover, since it is simple in form, it is easy to fill the concrete, and there is little possibility that the packing may be uneven.

Further, since high strength bolts such as friction welding high strength bolts and torsion type high strength bolts are used for joining the steel segments to each other, there is no need for skilled work, and highly reliable construction is possible in a short time.

Thus, since the annular segment wall has extremely low rigidity as a reinforcing material, there is no need for a reinforcing reinforcing material, and even if necessary, the amount of reinforcing reinforcing material can be extremely small. .

Further, when a steel segment having a skirt metal fitting for opening and closing is used on the connection side, there is an advantage of reducing leakage of the filled concrete, and a steel segment having a grid-like rib having a warped side rib is used. In this case, since there is no hard-to-fill pocket portion that is likely to be formed below the base of the horizontal rib, there is an advantage that concrete can be more densely filled.

Next, the steel segment for construction according to the present invention, in advance, considering the curvature of the desired cylindrical drilling hole peripheral surface,
In the circumferential direction and vertical direction welded to the skin plate and the inner peripheral surface of the skin plate bent to the set curvature,
Lattice-shaped ribs having frictional joints provided with through holes for bolt joints In other words, since they are composed of curved lattice-like ribs that are in close contact with the inner peripheral surface of the skin plate, the structure is simple and therefore the manufacturing is also easy. It has the advantage of being easy and inexpensive.

Further, the grid-like ribs welded to the inner peripheral surface of the skin plate have friction-joined hands provided with through holes for bolt joints at circumferential and vertical ends, so that the steel segments are attached to each other. Friction welding can be easily performed via the plate.

Furthermore, when a skirt metal fitting for closing the gap is provided on the outer peripheral surface of the steel segment on the connection side of the skin plate, a gap that easily occurs at the contact portion between the steel segments can be closed. The concrete leakage is reduced and reliability and economy can be improved.

(Example) Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic perspective view of such a steel segment 1 according to the present invention, showing an inner peripheral surface of a skin plate 2 curved to a set curvature.
2a has a lateral rib 3 curved so as to be in close contact with the inner peripheral surface 2a.
Similarly, a lattice-like rib 5 composed of a vertical rib 4 whose side surface is in close contact with the inner peripheral surface 2a is welded.

Thus, the ends of the horizontal ribs 3 and the vertical ribs 4 have a frictional joint 7 having a set number of through holes 6 for bolting and a frictional joint having the same number of through holes 8 for bolting. 9 is formed in a friction welding joint. A skirt metal fitting 10 for closing a gap, which is provided as required, is welded to the outer surface on the connection side of the skin plate 2.

FIG. 2 is a landslide prevention steel pipe pile 11 formed by jointing a plurality of the steel segments 1 in a circumferential direction and a vertical direction.
10a to 10c show skirt fittings for closing the gap. FIG. 3 is a partial cross-sectional view for explaining the above-mentioned friction joining, in which bolts formed at the ends of the longitudinal ribs corresponding to the lattice-shaped ribs whose end faces abut on adjacent steel segments. The joints 9a and 9b for friction joining provided with through holes are provided with joining plates 12a and 12b each having a steel plate surface with through holes for bolt joining, and high-strength bolts for joining having through holes between the joint and the attaching plate. They are friction-joined by 13a and 13b. The number of high-strength bolts used for friction joining is as follows:
It is determined according to the desired bonding strength.

Due to such frictional joining of the steel segments, the cylindrical structure becomes very strong, and there is no danger of breaking from the joint portion even when a large bending or shearing force is applied.

In addition, when a torsion-type high-strength bolt is employed as the high-strength bolt for friction joining, the tightening force can be made constant, and the work is easy, and the working time for joining can be reduced. Become.

Thus, the conventional method, as shown in FIG.
4b is tightened with the bolt 15, so that the load is transmitted by the bolt 15, so that indirect load transmission results in insufficient rigidity and proof strength, but in contrast, the friction joining method according to the present invention Since the load is reliably transmitted through the attachment plate, the rigidity and the proof stress are extremely high, and the structural reliability is large.

Fig. 5 shows a cylindrical borehole 16 excavated to prevent landslides.
Next, the annular segment wall 17 constructed by the method of the present invention
In this figure, concrete is filled into the gap between the outside of the annular segment wall 17 and the cylindrical excavation hole 16 and the inner hole of the annular segment wall 17 to constitute a landslide prevention pile.

At this time, an appropriate reinforcing bar is inserted into the lumen of the annular segment wall 17 as needed.

Next, the horizontal rib 3 and the vertical rib 4 in the concrete filling
The problem at the intersection with will be described with reference to the partial perspective view of FIG.

Now, when the steel segments 1 are joined and filled with concrete as in the construction of the landslide prevention pile, concrete is difficult to enter under the base of the lateral ribs 3, that is, near the welded portion with the skin plate, so-called difficult-to-fill pocket. In particular, the intersection of the horizontal rib 3 and the vertical rib 4 tends to be a space in which air or excess water accumulates.

If said space is not filled with concrete,
Rust and the like can damage the steel segment, which is a structural weakness.

FIG. 7 is a partial perspective view showing the grid-like rib 18 having no such a defect. The vertical rib 4a extends in the vertical direction.
The horizontal rib 3a is assembled in an upward warp.

Accordingly, since there is no difficult-to-fill pocket portion, the concrete is smoothly filled, and no structural weakness is generated.

Although the present invention has been described by taking the landslide prevention pile as an example, the present invention can also be applied to construction of a tunnel, an underpass, a storage tank, a basement, and the like. That is, in the case of a tunnel or an underpass, the method for constructing a cylindrical structure and the steel segment for construction of the present invention are applied in the horizontal direction.

(Effects of the Invention) The present invention provides a construction method that enables efficient work in constructing a cylindrical structure, is mechanically safe, has high reliability, and is economically advantageous. In addition to the above, it is possible to provide a structural steel segment which is easy in structure, inexpensive, and excellent in strength, so that its practical effect is extremely large.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a steel segment according to the present invention, FIG. 2 is a partially cutaway perspective view of a landslide prevention steel pipe pile, and FIG.
The figure is a partial sectional view for explaining the friction welding, and FIG.
FIG. 5 is a schematic cross-sectional view for explaining load transmission by a conventional bolt joint, FIG. 5 is a schematic perspective view showing an annular segment wall constructed by a method of the present invention in a cylindrical drill hole, and FIG.
The figure is a partial perspective view of the intersection of a horizontal rib and a vertical rib, and FIG. 7 is a partial schematic cross-sectional view of a grid-like rib provided with a warped horizontal rib. 1: steel segment, 1a: steel segment, 2: skin plate, 2a: inner peripheral surface, 2a: outer peripheral surface, 3: horizontal rib, 3a: horizontal rib, 4: vertical rib, 4a: vertical rib, 5: Lattice rib, 6: Through hole, 7: Friction joint,
8: Through hole, 9: Friction joint, 9a: Friction joint, 9b: Friction joint, 10: Skirt fitting, 10a to 10c: Skirt fitting, 11: Steel pipe pile for preventing landslide, 12a, 12b: Attached plate, 13a , 13b: High-strength bolt for friction welding, 14a, 4b: Rib, 15: Bolt, 16 cylindrical borehole, 17:
Annular segment wall, 18: lattice rib

Claims (5)

(57) [Claims] 1. A skin plate curved to a set curvature, and a grid-like rib having a friction joint joint provided with through holes for bolt joint at circumferential and vertical ends welded to an inner peripheral surface of the skin plate. After the steel segment consisting of, while successively friction-joining through the auxiliary plate, to construct an annular segment wall on the peripheral surface of the cylindrical drilling hole, between the outside of the annular segment wall and the cylindrical drilling hole and the A method for constructing a cylindrical structure in which concrete is filled into a lumen of an annular segment wall. 2. The method for constructing a cylindrical structure according to claim 1, wherein a steel segment having a skirt metal fitting for closing a gap is used on an outer surface on a connection side of the skin plate. 3. The method for constructing a cylindrical structure according to claim 1, wherein a steel segment provided with a grid-like rib having a warped lateral rib is used. 4. A skin plate curved to a set curvature, and a grid-like rib formed inside the skin plate and formed with a joint for frictional joining provided with a through hole for bolt joining at an end thereof. Steel segment for building cylindrical structures. 5. A skin plate curved to a set curvature, and a grid-like rib formed on the inside of the skin plate and forming a joint for frictional joining provided with a through hole for bolt joining at an end thereof. A steel segment for constructing a cylindrical structure, comprising a skirt metal fitting for closing a gap provided on an outer surface on the connection side of the skin plate.