JPH0647809B2 - Joint structure of blocks in connected block structure - Google Patents

Description

TECHNICAL FIELD The present invention relates to a block joint structure suitable for use in a piled connection block structure constructed as an offshore structure such as a breakwater, for example.

"Prior Art" As a marine structure such as a breakwater, there is a piled connection block structure. This is a structure as shown in FIGS. 6 and 7, for example. That is, a plurality of piles 2 driven into the seabed 1 are used as a foundation, and a precast concrete block (hereinafter referred to as a block) 4 having holes 3 and flat upper and lower surfaces allows the piles 2 to be loosely inserted into the holes 3. In this state, the piles 2 are bridged and piled up in multiple layers in a grid pattern. The pile 2 and the block 4 are suspended from the vicinity of the upper end of the pile 2 by a PC steel material 7 to grip the pile 2 and hold the block 4 from below.
And the holes 3 of the concrete block 4 and the filling mortar 6 filled between the piles 2 and the blocks 4 are connected together along the piles 2.
Prestress is introduced by the tension of the PC steel material 7 suspended in the gap between the two and they are integrated.

According to the piled connection block structure having the above structure, the structure can be quickly and safely constructed on the soft ground without performing the ground improvement or underwater work, and the workability at sea is good. There is.

However, in the above-mentioned structure, the blocks may come into point contact with each other at the points of the convex portions due to the unevenness of the joint surface caused by the manufacturing error of the block 4, and prestress is introduced in such a case. Then, stress concentration occurs in the convex portion, and as shown in FIG. 8, a crack is generated due to a tensile stress (stress in the X direction) parallel to the joint surface.

Further, since the PC steel material 7 is hung from the head of the pile 2, the position where the PC steel material 7 passes is determined by the position of the pile 2, and the PC steel material 7 is placed according to the driving accuracy of the pile 2. There is also a drawback that the bending strength of the pile changes due to the occurrence of an eccentric moment (prestress moment) due to the tension. Further, a plurality of PC steel materials 7 are placed in the holes 3 of the block 4.
Since the internal space is complicated, the mortar filling work becomes complicated and the workability deteriorates.
Even if it is necessary to increase the bending resistance of the columnar body formed of C steel material, blocks, and filling mortar, it is difficult to arrange a large number of PC steel materials in the internal space.
Also, a guide or the like is required to install the block in the correct position.

Therefore, as a result of diligent research to solve these problems, the present applicants, as shown in FIG. 9, dispose joints 8 at the joints of blocks 4 and connect blocks 4 to each other. If it is integrated with the PC steel material that penetrates through, the stress generated in the joint surface of the block by the joint portion 8 can be made uniform, and the position of the PC steel material is at a fixed position regardless of the driving accuracy of the pile. The placing accuracy does not affect the bending strength, and the PC steel material can be arranged without being limited to the narrow space of the pile and the block hole for improving the bending strength of the column body. We paid attention to the fact that the installation accuracy of can be dramatically improved, and that the work of filling mortar on site is also easy.

"Problems to be Solved by the Invention" However, even with the above-described structure, for example, the following problems remain to be solved.

If the joint portion 8 is a rubber sheet or urethane mat for the purpose of merely preventing leakage and stopping water, it does not have the compressive strength and elastic modulus equal to or higher than that of concrete, so that it is shown in FIG. As described above, it is impossible to prevent the stress concentration at the convex portion due to the large deformation thereof and the partial cutting at the convex portion.

When the joint portion 8 has a strength equivalent to that of concrete, for example, an underwater-curable resin-based adhesive material or an underwater-curable underwater non-separable mortar, the above-mentioned problems can be solved, but these joints can be solved. Since the material is in a fluid state before curing, when the joint material is applied or when the PC steel material 7 is tensioned, the joint material may leak into the PC steel material insertion hole, and it may not be possible to grout into the insertion hole after tensioning. To be.

It is difficult to insert the PC steel material into the insertion hole when arranging the blocks (when stacking), and the workability deteriorates.

"Means for solving the problem" So, the present invention, a plurality of precast concrete blocks, while stacking on the joint surface of each block provided with joints made of underwater curing type joint material,
A connecting block structure in which the blocks are integrated by a PC steel material penetrating each block, wherein the joining structure of the blocks is a joining surface facing the inner upper portion of the joining surfaces of the vertically adjacent blocks, The sheath tube forming the PC steel material insertion hole is projected upward from the joint surface, while the protruding portion of the sheath tube is loosely inserted and a fitting hole communicating with the PC steel material insertion hole is formed on the joint surface facing the lower part. Moreover, the inner surface of the fitting hole is formed in a tapered shape that is tapered toward the inner side.

[Operation] According to the above configuration, it is easy to arrange a large number of PC steel materials, and the proof stress of the structure can be easily improved, and the joint material into the insertion hole is formed by the sheath tube projecting to the joint surface facing the upper part. Of the PC steel material is inserted into the fitting hole of the joining surface facing the lower part, the tip of the PC steel material is guided into the insertion hole by the tapered surface at the back of the fitting hole. The insertion work becomes easier,
The workability can be improved.

[Example] Hereinafter, the present invention will be described with reference to Figs. 1 to 5. It should be noted that the present embodiment is applied to a pile driving connection block structure which is one of the connection block structures.

In these drawings, reference numeral 10 is a pile driven into the seabed 1, and a receiving block 11 is arranged below the pile 10 and an annular precast concrete block 12 is provided on the receiving block 11. 13 ……,
Are stacked, and each of these blocks 12, 13 ...
,, the lower end of which is fixed to block 12 and each block 1
3 ... are integrated by a plurality of PC steel materials 14. A joint portion 15 made of an underwater curing joint material is formed on each joint surface of the blocks 12, 13 ...
, And a filling material 16 such as mortar is injected and filled into the internal space surrounded by the blocks 12, 13 ...

The block 12 is disposed at the lowermost end of the connection block structure, and the reinforcing bar is embedded inside, and the fixing portion 17 at the lower end of the PC steel material 14 is embedded, and further from the fixing portion 17 to the upper end. A sheath tube 18 is provided so as to cover the PC steel material 14 toward. A grout injection hole 19 communicates with the lower end of the sheath tube 18.

On the other hand, the block 13 to be stacked on the block 12 has a reinforcing bar embedded therein similarly to the block 12, and has an insertion hole for the PC steel material 14 formed inside the concrete as shown in FIG. The sheath tube 18 is buried.

The structure of the joint between the blocks 12, 13, ... Is shown in FIGS. 2 and 3. That is, the sheath tube 18 forming the PC steel material insertion hole projects upward from the joint surface 12a on the joint surface 12a facing the inner upper part of the joint surfaces of the blocks 12 and 13 that are vertically adjacent to each other. A fitting hole 20 that loosely inserts the protruding portion of the sheath tube 18 and communicates with the PC steel material insertion hole is formed in the joint surface 13a facing the lower part.
The back surface 20a of 0 is formed in a taper shape (for example, a conical shape) which is tapered toward the back side (upper side in the drawing).

Here, as shown in FIG. 2, the protruding length H of the sheath tube 18 may be higher than the thickness of the joint portion 15 provided on the joint surface. For example, the coating thickness of the joint material is usually uneven on the joint surface. Since it has a size (10 mm to 3 mm) capable of absorbing the above, the height is set to correspond to the range of this size.

In addition, a packing 25 is provided on the joint surface 12a facing the upper part so as to surround the sheath tube 18 as shown in FIG.

Although an example of the joint portion between the blocks 12 and 13 has been described above, the structure of the joint portion between the blocks 13 is similar to that of the joint portion between the blocks 12 and 13, and thus the description thereof is omitted.

Next, regarding the action of the joint portion configured as described above,
A description will be given according to the construction procedure of this piled connection block structure.

As shown in FIG. 1, in order to construct a piled connection block structure, a pile 10 is driven into the seabed 1, a receiving block 11 is set under the pile 10, and then a receiving block 11 is placed on the receiving block 11. The block 12 is placed, and the block 13 is sequentially stacked on the block 12 while inserting the PC steel material 14 into the sheath tube 18. The insertion operation of the PC steel material 14 is an operation of inserting the tip of the PC steel material 14 into the fitting hole 20 of the joint surface 13a facing the lower part of the block 13, and particularly, the back surface 20a of the fitting hole 20 is at the back side. Since it is formed in a tapered shape as it goes to, the PC steel material 14 is guided along the taper to the sheath tube 18 as it is inserted. Therefore, the PC steel material 14 can be easily charged and the workability is improved. be able to.

When the blocks are stacked, a water-curable epoxy compound (for example, product name Subcoat S Venetian Anison Cavernichi Co., Ltd.) or the like is used as a joint material on the joint surface 13a facing the lower end of the block 13, that is, the lower part, with a thickness of 5 mm or more. Apply. The material of the joint material is not limited to the epoxy compound, but a water-curable resin-based adhesive material or a special admixture (for example, trade name Acris 12 manufactured by Nisso Master Builders)
It may be a mortar or the like which is blended with to give inseparability in water.

Then, after stacking the blocks 12 and 13, the PC steel material 14 is tensioned with a jack by using the blocks as a reaction force, and the filling material 16 is filled in the internal space surrounded by the blocks 12 and 13 and the piles 10. It will be in the assembled state as shown in the figure.

It should be noted that, at the time of the construction, the joint material of the block tries to flow into the sheath tube 18 by applying the joint material, but in the present embodiment, the upper portion of the sheath tube 18 projects, so that Since the inflow is prevented and the projecting portion of the sheath tube 18 is housed in the fitting hole 20, the projecting portion of the sheath tube 18 does not obstruct the stacking of the blocks. Therefore, the joint portion 15 and each block 1 having strength equal to or higher than that of concrete
It is possible to improve the applicability to the construction of a piled connection block structure or the like in which the blocks are integrated by the PC steel material 14 penetrating the Nos. 2 and 13, and thus the block 1
It is possible to equalize the stress generated on the joint surface of 2, 13, ..., and it is possible to suppress the influence of the pile construction accuracy on the bending strength of the column, and more than in the past. Since the PC steel material can be arranged, it becomes easy to increase the proof stress of the structure, the installation accuracy of the block is dramatically improved, and the work of filling the mortar on the site becomes easy.

"Effects of the Invention" As described above, according to the present invention, the following excellent effects are exhibited.

(a) Since it is possible to arrange the PC steel material so as to penetrate the block and a large number of PC steel materials can be easily arranged, it is possible to easily improve the yield strength of the structure.

(b) The sheath tube protruding to the joint surface facing the upper part can prevent leakage of the fluid joint material into the insertion hole, and the PC steel material is inserted into the fitting hole of the joint surface facing the lower part. By doing so, the front end of the PC steel material is guided into the insertion hole by the tapered surface at the back of the fitting hole, so that the workability at the time of stacking the blocks can be improved.

(c) From the above, it is possible to improve the applicability to the construction of a piled connection block structure or the like in which the blocks are integrated with the joint portion having the strength equal to or higher than that of concrete and the PC steel material penetrating each block. .

[Brief description of drawings]

1 to 5 show an embodiment of the present invention.
FIG. 1 is a half cross-sectional view of a piled connection block structure, FIGS. 2 and 3 are cross-sectional views each showing a structure of a joint portion of the block, FIG. 4 is a perspective view of the block, and FIG. 5 is a sheath tube. Fig. 6 is a plan view showing a state in which packing is attached to the periphery of Fig. 6, and Figs. 6 to 9 each show a conventional example of a pile driving connection block structure in the case of a breakwater. Fig. 6 is a partial cutout. FIG. 7 is a perspective view, FIG. 7 is a sectional view for explaining the construction method, FIG. 8 is a sectional view of a joint portion, and FIG. 9 is a sectional view of a joint portion in which a joint material is arranged. 1 ... sea bottom, 10 ... pile, 11 ... receiving block, 1
2, 13 ... Precast concrete blocks, 14
...... PC steel, 15 …… joints, 16 …… filling material, 17
...... Fixing part, 18 ...... sheath tube, 20 ...... fitting hole, 20
a: The inner surface of the fitting hole.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshimi Suzuki, 2-16-1 Kyobashi, Chuo-ku, Tokyo Within Shimizu Construction Co., Ltd. (72) Juichi Ise 2--16-1, Kyobashi, Chuo-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Takuro Odawara 2-16-1 Kyobashi, Chuo-ku, Tokyo Shimizu Construction Co., Ltd.

Claims (1)

[Claims] 1. A plurality of precast concrete blocks are stacked on each other with joints made of underwater hardening type joint material provided on the joint surface of each block, and the blocks are integrated by a PC steel material penetrating each block. In the joint structure of blocks in a connected block structure that is made into a structure, a sheath tube forming a PC steel insertion hole is formed from the joint surface on the joint surface facing the inner upper portion of the joint surface of both vertically adjacent blocks. Also protrudes upward, and on the other hand, a fitting hole which loosely inserts the protruding part of the sheath tube and communicates with the PC steel material insertion hole is formed on the joint surface facing the lower part, and the inner surface of the fitting hole is The joining structure of blocks in a connecting block structure, wherein the joining structure of the blocks is formed in a tapered shape that is tapered toward the inner side.