JPS58113410A - Horizontal setting work of gravity structure - Google Patents

Abstract

PURPOSE:To horizontally set a caisson by leveling off the surface of crushed stones by a method in which a bag is laid on the crushed stones, a filler is charged into the bag and hardened, and then the caisson is set up. CONSTITUTION:In setting a gravity structure 3, e.g., concrete caisson, blocks, etc., a bag 6 to be filled with a filler is laid over crushed stones 2 covered on the seabed. Then, the structure 3 is hung down and stopped at a position keeping a slight distance from the bag 6, a filler, e.g., cement mortar, etc., is charged into the bag 6 and hardened, and then the structure 3 is set on the bag. Thus, the gravity structure can be set horizontally and the loading distribution of the structure can be equalized, so that stable foundation work can be attained.

Description

[Detailed Description of the Invention] The present invention relates to a horizontal installation method for gravity-type structures such as concrete caissons and blocks. Caissons and blocks are indispensable for foundation work such as undersea oil fields and port construction. However, the method of installing it horizontally on h paper has not yet been established. As shown in Figure 1, Yakumei laid down the seabed 1, laid down crushed stone 2, placed concrete caisson 3 on top of this, and then built an oil field base. Although the crushed stone 2 is leveled to some extent by the diver, it cannot be expected that the surface will be that horizontal or flat. Therefore, there is a risk that the caisson will be placed tilted as shown in Figure m2, and it is extremely difficult to correct this. Furthermore, if the crushed stone surface is not flat, the load of the caisson will be concentrated only on the crushed stones that are in contact with it, making it extremely unstable. Looking at this from the caisson side, the parts that are in contact with crushed stone are extremely susceptible to damage. This Yuzu concrete caisson has an empty part 4a for ballast water, etc.
4b, and the bottom surface is not that thick.

Therefore, it must be said that the risk of failure is even greater.

Therefore, the first object of the present invention is to straighten the crushed stone surface and install the caisson horizontally. The purpose of younger brother 2 is to bring the entire bottom of the caisson into contact with the crushed stone and to equalize the distribution of the load on the caisson. In order to achieve this purpose, in the present invention, a bag is spread over crushed stone, a filler is injected into the bag, and the bag is solidified, and then the Karason is placed thereon. Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 3 shows a perspective view of the bag 6 for filler.

Filler injection tubes 7a and 7b are inserted into the bag 6, and each injection tube 7a and 7b is provided with a number of filler outlet holes 8. One end of the injection pipes 7a, 7b protrudes outside the bag, and a hose for feeding the filler (see FIG. 4) is connected to this end. Also two injection pipes 7m.

Since 7b gives the bag 6 some degree of rigidity, it also has the advantage of being easy to sink on the quarry surface. Therefore, if the bag 6 can be easily expanded due to the site conditions, the filler may be directly injected into the bag without the injection tube. The bag 6 may be made of cloth, rubber, or the like, but the use of Fapley sheet is advantageous in that water that has entered the bag as the filler is press-fitted can be discharged from the joints.

Next, the construction sequence of the present invention will be explained according to FIG. First, the bag 6 is placed on the crushed stone 2. This work may be performed by a dialer, or may be lifted and lowered by a crane. Of course, it is important to remove air so that it does not float up due to buoyancy,
Even so, the larger the bag 6, the more difficult the work will be. In such a case, the bag 6 may be rolled up and lowered, and then unfolded on the seabed. Next, the injection tube 7m protruding from the bag 6
.

A hose 9 is connected to the end of 7b, and the other end of the hose 9 is made to protrude above the sea surface. Next, the sicaison 3 is lowered by a crane, but is temporarily held at a position 10~20c+a away from the bag 6. Naturally, Caisson 3 remains horizontal in this state. When a filler such as mortar is press-fitted from the upper end of the hose 9, the bag 6 expands so that the upper surface contacts the bottom surface of the caisson, and the lower surface enters the gap between the crushed stones 2. Therefore, once the filler in the bag is solidified, the entire top surface of the bag 6 forms a horizontal flat surface. (In the diagram, the injection pipe inside the bag is omitted for convenience of explanation.) After that, just remove the crane hoist 10 and the caisson 3
will be installed completely horizontally. Note that if the caisson is extremely large, a considerable number of bags will be required, and it will be difficult to inject filler into the bags placed near the center. In such cases, it is best to connect the injection tubes of the bags with a joint.

According to the construction method of the present invention, such as diagonal construction, gravity-type structures can be installed horizontally, and the load distribution of the structure is equalized, so there is an advantage that stable foundation construction can be carried out.

[Brief explanation of the drawing]

Figure 1 is a simplified diagram of a caisson installed on the seabed, Figure 2 is an enlarged view of the bottom of the concrete caisson, Figure 3 is a perspective view of a bag for filler, and Figure 4 shows the construction method of the present invention. The simplified diagram shown is 01: seabed, 2: crushed stone, 3: concrete, 1 note caisson, 5: water surface, 6: bag for filler,
7m, 7b...Injection pipe, 8...Filling agent outflow hole-4/〒 Figure 1 Figure 3 w! 44Figure 45-

Claims (1)

[Claims] When placing gravity-type structures such as concrete caissons and blocks on the seabed, first, a bag for filler is laid out on crushed stones spread on the seabed, and then the structure described in 1 is suspended. The method is characterized in that the cocoon structure is temporarily placed on a VC after being lowered and temporarily stopped at a position leaving a slight gap with the bag, and a filler is introduced into the bag and solidified. Horizontal installation method for gravity structures.