JPH0555647B2 - - Google Patents

Description

Detailed Description of the Invention "Industrial Application Field" The present invention is based on stacking a plurality of precast concrete blocks so that pre-driven piles can be inserted through them, and arranging steel materials so that they can be inserted through each of these blocks. An RC structure is formed by applying grout between the steel material and the steel material insertion hole of the block, and by filling mortar or concrete between the pile and the pile insertion hole of the RC structure. This invention relates to a joint structure of a connected block structure in which the RC structure and the pile are integrated.

``Prior Art'' An example of a connected block structure is a piled connected block structure that is applied to marine structures such as breakwaters. This is true for example in Figures 13 and 1.
As shown in Figure 4, a plurality of piles 2 driven into the seabed 1 serve as a foundation, and a precast concrete block (hereinafter referred to as block) 4 having holes 3 and flat upper and lower surfaces supports the piles 2. They are loosely inserted into the holes 3, spanned between the piles 2, and stacked in multiple stages in a grid pattern. The pile 2 and the block 4 are connected to a wedge fastening device 5 which is suspended from near the upper end of the pile 2 by a steel member 7 passing through a hole 3 to grip the pile 2 and hold the block 4 from below, and a concrete block. The holes 3 of 4 and the piles 2 are integrally connected by filling mortar 6 filled between the holes 3 and the piles 2.

According to the piled connected block structure of the above structure,
Almost no ground improvement or underwater work is required.
It has the advantage of being able to quickly and safely construct structures on soft ground and being easy to work with at sea.

"Problem to be solved by the invention" However, regarding the above-mentioned structure,
Since the steel material 7 is passed through the hole 3 for inserting the pile 2, the following problems have arisen.

In terms of strength, it is preferable to match the centroid of the concrete cross section with the centroids of the plurality of steel members 7, but since the steel members 7 move freely within the hole 3, it is difficult to match the centroids.

Since the distance from the compression edge to the steel material 7 is short and the number of steel materials 7 disposed is limited, the bending strength is small considering the shape.

When joining the blocks 4 underwater, special measures are required such as having a diver monitor and guiding them or using a special guide jig so that the surfaces do not become misaligned.

Therefore, as a result of intensive research to solve these problems, the present inventors created steel insertion holes in the precast concrete block separately from the pile insertion holes, and set intervals in the circumferential direction on the outside of the pile insertion holes. If the structure is provided with an opening, the steel material can be used as a guide when passing the steel material through the precast concrete block and lowering it, improving the accuracy of block placement compared to the above method. We focused on the fact that it can be placed close to the body, resulting in advantages such as increased bending strength.

However, even if such a structure is adopted, it is necessary to increase the joint strength between the precast concrete blocks to a certain extent and to prevent stress concentration from occurring on the convex portions of both joint surfaces, as shown in Figure 15. becomes. In order to increase the joint strength between precast concrete blocks, it is effective to insert a joint material between them, but since the precast concrete blocks are stacked underwater, Even when joint materials are applied to the upper surface, there is a problem in that they are washed away by waves and currents.

The present invention was proposed in view of the above circumstances, and
The aim is to provide a joint structure for connecting block structures which can solve the above-mentioned problems.

``Means for Solving the Problems'' Therefore, the joint structure of the connecting block structure of the present invention is such that a plurality of steel insertion holes formed in the precast concrete block are arranged outside the pile insertion holes separately from the pile insertion holes. are provided at intervals in the circumferential direction, and double-sized ring-shaped packings are provided between the precast concrete blocks so as to surround the portions in which the plurality of steel insertion holes are formed, and these two It is characterized by a joint material interposed between the heavy ring-shaped packings.

``Function'' Since the joint material is interposed between two large and small ring-shaped packings, even when the joint material is applied onto the precast concrete block and submerged in water, the joint material remains intact. It is less likely to be washed away or peeled off by waves or currents, and is easy to install.

"Embodiments" Examples of the present invention will be described below with reference to FIGS. 1 to 12.

In these figures, reference numeral 10 is a pile driven into the seabed 1, and a receiving block 11 is fixed to the lower part of this pile 10, and on top of this receiving block 11, an annular precast concrete block 12, 13..., are stacked on top of each other, and a plurality of steel members 14 are arranged, each having its lower end fixed to the block 12 and extending upward so as to pass through each block 13.... Then, by applying grout between the stripped material 14 and the steel material insertion holes of the blocks 12 and 13, each block 12 and 13
It is integrated as an RC structure.

Each joint surface of the blocks 12, 13, . . . is provided with a joint portion 15 made of an underwater curable resin adhesive material or an underwater inseparable mortar material. Here, Subcoat S (manufactured by Venetian Sonca Bernici) is used as an underwater-curable resin-based adhesive material, and early-strength Portland cement is used as an underwater-curable non-separable mortar material. Fine aggregate, special admixture (for example, product name Akris 12 manufactured by Nisso Master Builders, etc.)
A mixture containing the following in a predetermined proportion is used. These joint materials have strength comparable to or greater than concrete.

Further, each block 12, 13, . has been done.

Next, the blocks 12, 13, etc. will be explained in detail. The block 12 is arranged at the lowest end of the connecting block structure, and reinforcing bars are embedded inside, and the lower end of the steel material 14 is fixed. The fixing section 17 is buried, and the fixing section 17
A sheath pipe 18 is provided so as to cover the steel material 14 from the top toward the top end. The sheath tube 18 is arranged separately from the pile insertion hole 3 at intervals in the circumferential direction on the outside of the pile insertion hole 3. Note that a grout injection hole 19 communicates with the lower end of this sheath pipe 18 .

On the other hand, the block 13 stacked on top of this block 12 has reinforcing bars buried inside it like the block 12, and a sheath that forms an insertion hole for a steel material 14 inside the concrete, as shown in FIG. A pipe 18 is buried.

The structure of the joints of the blocks 12, 13, . . . is as shown in FIGS. 6 and 7. In other words, both vertically adjacent blocks 1
A sheath pipe 18 protrudes above the joint surface 12a so as not to be blocked by the joint material on the joint surface 12a facing the inner upper part of the joint surfaces facing each other. A fitting hole 20 is formed in the surface 13a, into which the protrusion of the sheath tube 18 is loosely inserted and which communicates with the steel material insertion hole. It is formed in a tapered shape (for example, a conical shape).

Here, the protrusion length H of the sheath tube 18 is the sixth
As shown in the figure, it is sufficient that the thickness is higher than the thickness T of the joint portion 15 provided on the joint surface.For example, the thickness of the joint material applied is usually large enough to absorb the unevenness of the joint surface (10 mm to 3 mm). Therefore, the height is set to correspond to this size range.

Although the example of the joint between the blocks 12 and 13 has been described above, the structure of the joint between the blocks 13 is also similar to that of the joint between the blocks 12 and 13, so a description thereof will be omitted.

The adhesion force of the filler material 16 influences the bonding force between the pile 10 and each block 12, 13 of the RC structure, and in order to increase the bonding force, the filler material 16
High-strength, non-breathing prepact mortar or underwater concrete is used.
Further, the pile 10 is made of a steel pipe having ribs R and dowels formed on the outer surface.

Next, a method of constructing the connecting block structure will be explained.

To construct this piled connected block structure,
First, as shown in FIG. 1, a pile 10 is driven into the seabed 1, a receiving block 11 is set at the bottom of this pile 10, a block 12 is placed on top of this receiving block 11, and a block 12 is placed on top of this receiving block 11. Steel material 1
4 into the sheath tube 18, the blocks 13 are stacked in order as shown in FIG.

The insertion operation of the steel material 14 involves inserting the tip of the steel material 14 into the fitting hole 2 of the joint surface 13a facing the lower part of the block 13.
In particular, since the inner surface 20a of the fitting hole 20 is tapered toward the inner side, the steel material 14 is guided into the sheath pipe 18 along the taper as it is inserted. will be
Therefore, the steel material 14 can be easily inserted and workability can be improved.

Note that when stacking the blocks 12 and 13, if an underwater curing resin adhesive material is used as the joint material between the blocks, the sixth
As shown in the figure, after the lower joint material of the upper block 13 is applied on land, it is lowered into the sea, and is mated and joined with the lower block 12 that has been installed in advance. At that time, as shown in FIG.
serves as a guide, and each block 13 can be lowered and installed with high precision as shown in FIG.

In addition, if the joint material is, for example, an underwater curing resin-based adhesive material, its hardness can be adjusted by mixing the main agent and a hardening agent, and it can have a hardness similar to that of a cement paste before hardening. Therefore, it can be easily applied to the joint surfaces of blocks. Moreover, since the joint material has good adhesion and sticks well to concrete, it will not be washed away by waves or currents or peeled off when the block is installed underwater. Since the blocks are installed, the adhesive material deforms due to the weight of the blocks themselves, and the blocks become closer to each other.
It has the advantage that the space can be completely filled.

On the other hand, when a mortar material that is not separable in water is used as the joint material, as shown in FIG. 1st
As shown in Figure 0, mortar 15 is laid down, suspended into water, and the next block 13 is installed before the joint material hardens.

After completing the installation of all blocks 12 and 13 through the above-mentioned work, a reaction force is taken on these blocks 12 and 13, and a tensile force of about 5 to 6 kg/cm ² is introduced to an arbitrary number of steel members 14 using jacks. do. This makes the bonding state between the blocks 12 and 13 more reliable. In this state, grout is injected from the injection port 19, and the blocks 12 and 13 are integrated into the RC
Make it a structure.

Next, mortar or concrete is filled between the pile 10 and the pile insertion hole 3, and the pile 10 and the blocks 12 and 13 of the RC structure are integrated (see Fig. 3).

According to the connected block structure having the above configuration, not only the blocks 12 and 13 are integrated with each other by the RC structure, but also the filler 16 injected between the pile 10 and the pile insertion hole 3 Since the blocks 12 and 13, which have an RC structure, and the pile 10 are integrated, the entire structure has strong rigidity.

In addition, if a pile 10 with a rib R or dowel formed on the outer periphery is used, the bonding strength between the pile 10 and the filling concrete (mortar) can be further strengthened, and in that case, bending force is applied. In this case, pile 10, filling concrete and block 12,
13 are deformed as one, and stronger yield strength can be exhibited.

Furthermore, in this embodiment, a joint 15 having a strength equal to or higher than that of concrete is provided between each block 12 and 13 in order to absorb the unevenness of the block surface, so that the force in the axial direction parallel to the pile 10 is Or if a bending moment is applied, each block 12, 1
It is possible to equalize the stress generated on the joint surfaces of No. 3, and to prevent problems such as stress concentration on the convex portions and cracks as shown in FIG. 15.

FIG. 11 shows another embodiment of the invention. The feature of this example is that adjacent sheath pipes (steel material insertion holes) 18 are communicated with each other through a communication hole 40.

In this way, when grouting the inside of the sheath pipe 18, it is sufficient to grout every other or every second part, which is particularly advantageous when there are many grouted parts.

FIG. 12 shows still another embodiment of the present invention. The feature of this example is that a fixing part 17 (filling anchor) is provided not in the block 12 at the lowest end but in the middle of the middle block 13, and the steel material 14 is extended upward from the middle of the block.

By doing this, block 1 of the RC structure
The amount of steel material can be changed from the middle of the cross section of the column consisting of 2 and 13, making it possible to ideally arrange the steel material according to the applied load.

"Effects of the Invention" As explained above, the present invention provides the following excellent effects.

Since the joint material is interposed between two large and small ring-shaped packings, even when the joint material is applied onto the precast concrete block and submerged in water, the joint material will not be affected by waves or currents. It is less likely to be washed away or peeled off by dirt, etc., making it easy to install.

In addition, even when a load is applied through the steel material so that the upper and lower precast concrete blocks approach each other with the joint material interposed between them, the action of the double ring-shaped packing is Therefore, it is possible to prevent the joint material from leaking out from between the two precast concrete blocks, and as a result, the construction can be carried out even more easily and reliably.

[Brief explanation of the drawing]

Figures 1 to 10 show an embodiment of the present invention, and Figures 1 to 3 are half-sectional views showing the construction procedure of a pile driving connected block structure, and Figure 4 is a perspective view of the block. Figure 5 is a plan view showing the packing attached around the sheath tube, Figures 6 and 7 are cross-sectional views showing the joints of the blocks, and Figure 8 is a diagram for explaining the action. The cross-sectional views shown in FIG. 9 and FIG. 10 respectively show the structure of the block when an underwater hardening type underwater non-separable mortar material is used as the joint material.
FIG. 9 is a plan view of the block, FIG. 10 is a sectional view of the main part, and FIGS. 11 and 12 are views showing other embodiments of the present invention. Figures 13 to 15 each show conventional examples of piled connecting block structures for breakwaters, with Figure 13 being a partially cutaway perspective view, and Figure 14 for explaining the construction method. FIG. 15 is a cross-sectional view of the joint portion. 1... seabed, 3... pile insertion hole, body 10... pile,
11...Receiving block, 12, 13...Precast concrete block, 14...Steel material, 15
... joint part, 16 ... filler, 17 ... fixing part,
18...Sheath pipe (steel material insertion hole).

Claims (1)

[Claims] 1. Drive piles so that the upper part protrudes, stack a plurality of precast concrete blocks with the piles inserted, arrange a plurality of steel members so that they are inserted through each of the plurality of precast concrete blocks, and By injecting grout between the pile and the steel insertion hole of the precast concrete block, and filling mortar or concrete between the pile and the pile insertion hole of the precast concrete block, the pile and the plurality of precast concrete blocks are connected. A joint structure between precast concrete blocks of a connected block structure in which cast concrete blocks are integrated, and a plurality of steel insertion holes formed in the precast concrete blocks are separate from the pile insertion holes. A double-sized ring-shaped packing is provided outside the pile insertion holes at intervals in the circumferential direction and between the precast concrete blocks so as to surround the portion where the plurality of steel insertion holes are formed. 1. A joint structure of a connecting block structure, characterized in that a joint material is interposed between the double ring-shaped butts.