JP5288202B2 - Impact resistance reinforcement method and impact resistance reinforcement structure for existing caisson - Google Patents

Description

  The present invention relates to an impact-resistant reinforcing method and an impact-resistant reinforcing structure for an existing caisson for performing impact-resistant reinforcement on a wave-dissipating block-covered caisson breakwater or a seawall.

  In the case of breakwater-block-covered caisson-type breakwaters and revetments, many cases of damage have been reported in which the wave-dissipating block moves due to the force of waves during high waves and collides with the caisson wall, causing cracks and holes. Yes. An example of the damage situation in a general caisson type breakwater is shown in FIG. FIG. 8 is a schematic diagram showing how the wave-dissipating block collides with the caisson.

  A general breakwater block type caisson breakwater is constructed by constructing a breakwater body 10 on a mound 20 laid on the seabed, and a wavebreak block 50 is placed on the side where the waves of the breakwater body 10 collide (for example, the open ocean side). It has a stacked structure. The breakwater main body 10 has a caisson 13 installed on a mound 20 laid on the seabed, and a filling material 14 such as sand is filled in the caisson 13, and a lid concrete 12 and an upper concrete 11 are placed on the upper part of the caisson 13. (See FIG. 2).

  In such a caisson-type breakwater, when high waves are generated due to the influence of a typhoon or the like, the wave-dissipating block 50 is moved by the energy of the waves and collides with the breakwater main body 10 as shown in FIG. There is a risk of scratching. If the caisson wall 15 is perforated, the filling material (not shown) filled in the caisson 13 flows out to reduce the weight of the caisson 13, thereby reducing the stability against breakwater sliding.

  As a method for improving the impact resistance of the existing caisson 13, the following two methods can be considered. FIG. 9 is a schematic diagram showing a first example of a conventional impact resistance reinforcing method, and FIG. 10 is a schematic diagram showing a second example of the conventional impact resistance reinforcing method.

  As shown in FIG. 9, the first impact-resistant reinforcement method temporarily removes the wave-dissipating block 50 installed outside the caisson wall 15, and casts concrete so that the concrete thickness of the caisson wall 15 increases. The reinforcing wall 200 is formed by adding a cushioning material or a steel plate to the front surface of the caisson wall 15.

  As shown in FIG. 10, the second impact-resistant reinforcing method is to temporarily remove the upper concrete 11 placed on the upper part of the caisson 13 and remove the filling material 14 and replace the filling material 14 with concrete 220. Or the iron plate 210 is attached to the inner surface of the caisson wall 15.

  Conventionally, various shear reinforcement methods for general reinforced concrete structures have been proposed (see Patent Document 1). In the technique described in Patent Document 1, a hole having a predetermined depth is drilled at a predetermined position of a reinforced concrete structure to be reinforced, and a rod-shaped reinforcing member is inserted into the hole, and then a self-curing filler is filled. It is what you do.

JP 2002-275927 A

  However, various disadvantages may occur in the conventional method described above. That is, in the first example of the conventional impact resistance reinforcing method, the work of removing the wave-dissipating block 50 is necessary, and the cost increases. Moreover, during the period when the wave-dissipating block 50 is removed, the breakwater is in an unstable state against waves. Furthermore, the wave-dissipating block 50 is in a stable state due to subsidence due to long-term waves and meshing of the wave-dissipating blocks 50, but by re-installing the wave-dissipating block 50, it was in a very stable state. The wave-dissipating block 50 returns to the initial unstable state.

  Moreover, in the 2nd example of the conventional impact-resistant reinforcement method, the removal work of the upper concrete 11 and the lid concrete 12 and the extraction work of the filling material 14 are required, and cost rises. Moreover, the breakwater is in an unstable state against waves during the period in which the upper concrete 11 is removed and the filling material 14 is removed.

  In addition, in the structure described in Patent Document 1, in a structure such as a reinforced concrete foundation, when the existing structure cannot secure sufficient safety against shear failure, only the shear strength is increased by increasing the amount of reinforcing bars. It is to improve. Therefore, as in the present invention, in a wall-shaped reinforced concrete structure, it is not possible to suppress bending deformation and improve resistance to punching shear failure. In addition, in the basic concrete that is the subject of the technique described in Patent Document 1, the reinforcing bars of the column members are usually fixed, or there are shear reinforcing bars installed at the time of new construction. It is not realistic to insert a reinforcing member from Furthermore, considering that the self-curing filler is poured, it is impossible to reinforce the target structure in the lateral direction.

  Moreover, the upper structure of a general wall structure has the superstructure of reinforced concrete, or the shear reinforcement reinforcement is arrange | positioned in the reinforcement of the wall itself, and it is difficult to perform reinforcement construction. In addition, there is a case where the upper concrete is not present in a wall portion of a structure such as a waterway or a semi-underground road, but in such a structure, there is no need for impact resistance reinforcement in the first place. On the other hand, the caisson has upper concrete and lid concrete at the upper part, but since unreinforced concrete is usually used, there is no restriction on drilling.

  The present invention has been proposed in view of the above-described circumstances, and it is not necessary to remove the wave-dissipating block disposed on the front surface of the caisson wall, to remove the upper concrete, and to remove the filling material at low cost. An object of the present invention is to provide an impact-resistant reinforcing method and an impact-resistant reinforcing structure for an existing caisson capable of performing impact-resistant reinforcement on a caisson-type breakwater or revetment covered with a wave-dissipating block.

The impact-resistant reinforcing method and impact-resistant reinforcing structure of the existing caisson of the present invention have the following characteristics in order to achieve the above-described object.
That is, the impact resistance reinforcement method for the existing caisson of the present invention is a method for impact resistance reinforcement for the wave-dissipating block-covered caisson type breakwater and revetment, and the filling material is formed from the upper part of the existing caisson. The step of drilling an insertion hole reaching the inside of the filled caisson, the step of inserting an injection tube into the insertion hole, and reinforcing the inner filling material by injecting a hardening material from the injection tube into the filling material, bending And a step of improving deformation resistance against punching shear fracture while suppressing deformation.
Here, the step of improving the resistance to punching shear fracture is a jet agitation method in which the filling material is agitated by rotating the injection nozzle, which is an injection pipe, to stir the filling material and to reinforce the filling material within a predetermined range. Is preferably adopted.

  At this time, after the step of drilling the insertion hole, the method includes a step of inserting a casing into the insertion hole, inserting an injection tube into the casing, positioning the casing, and then pulling out the casing. It is preferable to carry out after pulling out.

  The impact-resistant reinforcing structure of the existing caisson of the present invention is a shock-resistant reinforcing structure for a wave-dissipating block-covered caisson-type breakwater and a revetment, with respect to the filling material filled inside the caisson facing the wave-dissipating block, An impact-resistant reinforcing portion formed by injecting a hardening material through the insertion hole is provided. The impact-resistant reinforcing portion may be formed by a jet stirring method in which an injection nozzle that is an injection tube is inserted into the insertion hole to inject the cured material into the filling material, and the filling material is reinforced in a predetermined range. preferable.

  According to the impact-resistant reinforcing method and impact-resistant reinforcing structure of the existing caisson of the present invention, the filling material is reinforced by the so-called hardening stirrer jet stirring method without moving the wave-dissipating block or removing the filling material. By doing so, it is possible to suppress bending deformation and improve the resistance to punching shear fracture at low cost. Furthermore, since the wave-dissipating block is not moved, the stable state of the wave-dissipating block is not disturbed, and the impact-proof reinforcement work can be performed while the breakwater remains stable against waves.

  Further, by inserting a casing into the insertion hole and inserting an injection tube into the filling material using this casing, the reinforcing range can be set accurately and reliably. Furthermore, in the process of improving the yield strength against punching shear failure, the number of holes to be opened in the upper concrete can be reduced and the range can be solidified by using the jet stirring method.

The schematic diagram which shows the procedure of the impact-resistant reinforcement method of the existing caisson which concerns on embodiment of this invention. The schematic diagram of the caisson-type breakwater of the wave-dissipating block covering type which applies the impact-resistant reinforcement method and the impact-resistant reinforcement structure of the existing caisson concerning embodiment of this invention. The schematic diagram which shows the image of the impact-resistant reinforcement method and impact-resistant reinforcement structure of the existing caisson concerning embodiment of this invention. The schematic diagram which shows the outline | summary of a jet stirring construction method. The schematic diagram which shows the outline | summary of a jet stirring construction method. The schematic diagram which shows the outline | summary of a jet stirring construction method. The schematic diagram which shows the outline | summary of a jet stirring construction method. The schematic diagram which shows a mode that a wave-dissipating block collides with a caisson. The schematic diagram which shows the 1st example of the conventional impact-resistant reinforcement method. The schematic diagram which shows the 2nd example of the conventional impact-resistant reinforcement method.

<Outline of impact resistance reinforcement method and impact resistance reinforcement structure>
Hereinafter, with reference to the drawings, an embodiment of an impact resistance reinforcement method and an impact resistance reinforcement structure of an existing caisson according to the present invention will be described. FIG. 1 is a schematic diagram illustrating a procedure of an impact resistance reinforcing method for an existing caisson according to an embodiment of the present invention. FIG. 2 is a schematic diagram of a wave-dissipating block covering type caisson type breakwater to which the existing caisson impact resistance reinforcing method and impact resistance reinforcing structure according to the embodiment of the present invention are applied. FIG. 3 is a schematic diagram illustrating an image of an impact resistant reinforcement method and an impact resistant reinforcement structure of an existing caisson according to an embodiment of the present invention.

  The impact-resistant reinforcement method and the impact-resistant reinforcement structure of the existing caisson according to the embodiment of the present invention are for performing impact-resistant reinforcement on the caisson-type breakwater and revetment of the wave-dissipating block coating type, and in particular, bending deformation In addition, it is possible to improve the resistance to punching shear fracture. In the embodiment described below, the jet stirring method is used as a particularly preferable method in the step of improving the resistance to punching shear fracture. This is to reduce the number of holes opened in the upper concrete and enable solidification with a more limited range, but other solidification methods such as a chemical injection method can also be used in this process. . In the following embodiment, a caisson type breakwater will be described, but the present invention can of course be applied to a wave-dissipating block-covered caisson type revetment.

<Dissipating block-covered caisson breakwater>
As shown in FIG. 2, the wave-dissipating block-covered caisson type breakwater to which the impact-resistant reinforcement method and the impact-resistant reinforcement structure of the existing caisson according to the embodiment of the present invention are applied is formed on the mound 20 laid on the seabed. The main body 10 is constructed, and a wave-dissipating block 50 is stacked on the side where the waves of the breakwater main body 10 collide (for example, the open ocean side). The breakwater main body 10 has a covering stone 30 laid on a mound 20 laid on the seabed, a caisson 13 is set on the covering stone 30, and a filling material 14 such as sand is filled inside the caisson 13. The lid concrete 12 and the upper concrete 11 are placed on the upper part of the caisson 13. A root block 40 is installed on the side surface of the lower end portion of the caisson 13. The caisson 13 has a caisson wall 15 made of reinforced concrete as an outer shell, and an inner filler 14 is filled in the outer shell.

<Procedure for impact resistance reinforcement method>
Here, the structure of the caisson wall 15 on the front side can be considered as a surface member that is long in the vertical direction when the space between the two partition walls is considered. And as a failure mode, the bending failure of a short side direction, the bending failure of a long side direction, and a punching shear failure can be assumed. Among these failure modes, it can be considered that the punching of the caisson wall 15 in the wave-dissipating block 50 is particularly affected by the punching shear failure. Therefore, in the impact resistance reinforcement method and impact resistance reinforcement structure of the existing caisson according to the embodiment of the present invention, as shown in FIG. 1, for the purpose of suppressing bending deformation and improving the resistance to punching shear failure, The filling material 14 filled in the caisson 13 is reinforced in a predetermined range.

  That is, as shown in FIG. 3, the inside of the caisson 13 is filled with a filling material 14 such as sand, but the filling material 14 located on the front side facing the wave-dissipating block 50 is reinforced within a predetermined range. By forming the impact-resistant reinforcing portion 170, it is possible to suppress bending deformation and improve the resistance to punching shear failure.

The impact resistance reinforcing method for the existing caisson according to the present embodiment is performed in the procedure shown in FIGS. As described above, when the wave-dissipating block 50 is moved by the energy of the waves and collides with the breakwater main body 10 with respect to the caisson 13 before the impact resistance reinforcement is performed, there is a possibility that a hole is formed in the caisson wall 15.
Therefore, first, using the crawler drill 110, the insertion hole 120 that penetrates the lid concrete 12 from above the upper concrete 11 and reaches the inside of the caisson 13 filled with the filling material 14 is drilled (FIG. 1A). ). Subsequently, the casing 130 is inserted into the insertion hole 120 (FIG. 1B), and further, after the injection nozzle 140 is inserted into the casing 130, the casing 130 is pulled out (FIG. 1C). At this time, it is preferable to measure the accuracy of the insertion hole 120 and confirm that the injection nozzle 140 is inserted at an accurate position.

  Subsequently, while the injection nozzle 140 is rotated by the driving device 100, the curing material is injected to stir the filling material 14 (FIG. 1 (d)). At this time, by controlling the direction of the injection port (not shown) of the injection nozzle 140, it is possible to reinforce the filling material 14 within a desired range and form the impact-resistant reinforcing portion 170. And the impact-resistant reinforcement part 170 is formed in order, pulling out the injection nozzle 140 upwards (FIG.1 (e)), pulls out the injection nozzle 140, and the space | gap part of the insertion hole 120 of the upper concrete 11 and the lid concrete 12 Is filled with a filler 150 (FIG. 1 (f)). Although not shown, the injection nozzle 140 is connected to a storage tank for storing the curing material, a pump for delivering the curing material, and the like.

<Injection stirring method>
Next, a description will be given of an impact resistance reinforcement method for an existing caisson according to an embodiment of the present invention and a jet stirring method used in the impact resistance reinforcement structure. 4-7 is a schematic diagram which shows the outline | summary of a jet stirring construction method.
The injection agitation method is a method used for soil improvement, for example, and as shown in FIGS. 4 to 7, an injection nozzle 140 such as a perforated pipe having a plurality of injection ports 160 at the tip is inserted into the ground to be constructed. Then, the hardening material is injected from the injection port 160 at a predetermined pressure and a predetermined injection amount and the injection nozzle 140 is rotated, so that the hardening material is mixed while stirring the soil to improve the soil. Such a jet stirring method is characterized in that the soil can be improved within a desired range by adjusting the rotation range of the spray nozzle 140 and the spray pressure and spray amount of the hardener.

  Specifically, as shown in FIGS. 4 to 7, by adjusting the position of the injection port 160 and the rotation range of the injection nozzle 140 and injecting the curing material, a cylindrical shape (FIG. 4) and a wall shape (FIG. 5) Various ranges such as fan shape (FIG. 6), lattice shape (FIG. 7), etc. can be processed. In addition, the position of the injection port 160 may be one place, and may be two or more places. Further, when two or more injection ports 160 are provided, the curing material can be efficiently injected into a desired range by appropriately setting the positions.

<Other embodiments>
As described above, in the present embodiment, the impact resistance of the caisson 13 is enhanced by mixing the hardening material into the filling material 14 filled in the caisson 13 and reinforcing the filling material 14. In addition to performing such impact resistance reinforcement, a reinforcing member insertion hole is drilled from above the caisson wall 15 constituting the outer side surface of the caisson 13 toward the lower inside of the caisson wall 15, and the reinforcing member insertion hole is inserted into the reinforcing member insertion hole. By inserting a reinforcing member such as a reinforcing bar and filling with a self-curing filler, it is possible to further suppress bending deformation and improve the resistance to punching shear failure.

DESCRIPTION OF SYMBOLS 10 Breakwater main body 11 Upper concrete 12 Cover concrete 13 Caisson 14 Filling material 15 Caisson wall 20 Mound 30 Cover stone 40 Root block 50 Wave-dissipating block 60 Rebar 70 Punching device 80 Reinforcing member insertion hole 90 Rotating shaft 100 Drive device 110 Crawler drill 110 Filling nozzle 120 Insertion hole 130 Casing 140 Injection nozzle (injection tube)
DESCRIPTION OF SYMBOLS 150 Filler 160 Injection port 170 Impact-resistant reinforcement part 200 Reinforcement wall 210 Iron plate 220 Concrete

Claims (4)

A method for impact-resistant reinforcement of a wave-dissipating block-covered caisson-type breakwater and revetment,
Drilling an insertion hole reaching the inside of the caisson filled with the filling material from the upper part of the existing caisson;
Inserting an injection tube into the insertion hole;
Reinforcing the filling material by injecting a hardening material into the filling material from the injection tube, suppressing bending deformation and improving the resistance to punching shear fracture,
An impact-resistant reinforcing method for an existing caisson, characterized by comprising: The step of improving the resistance to punching shear failure is
The injection stirrer method is used, in which the hardening material is injected while rotating the injection nozzle that is the injection pipe to stir the filling material, and the filling material is reinforced in a predetermined range. Impact-proof reinforcement method for existing caisson. After the step of drilling the insertion hole, including inserting a casing into the insertion hole, inserting the injection tube into the casing and performing positioning, and then pulling out the casing;
3. The method for reinforcing impact resistance of an existing caisson according to claim 1, wherein the injection of the hardener is performed after the casing is pulled out. An anti-shock reinforcement structure for a wave-dissipating block-covered caisson breakwater and revetment,
Shock resistance of the existing caisson, which is equipped with an impact resistant reinforcement formed by injecting a hardening material through the insertion hole into the filling material filled in the caisson facing the wave-dissipating block Reinforced structure.

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