JPS5939011B2 - Offshore joining method for concrete floating bodies - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an offshore joining method for concrete floating bodies,
Particularly when constructing large-scale offshore structures, concrete floating boxes that have been divided into an appropriate number of units are positioned on the ocean, and then PC steel is stretched between the floating boxes. After temporarily fixing the end faces of the floating box in the correct position by manually pulling wire or other steel wire from both ends and applying tension, mortar is injected into the joint end faces to make the PC steel. By applying a constant tension to the wire, the floating boxes are firmly and integrally joined.

Generally, offshore structures are constructed by dry work at a dock and then towed to a predetermined offshore location.

However, as the scale of the structure increases, it becomes impossible to construct it using existing docks, and constructing a new dock requires a huge amount of construction costs. When an object is towed from a dock to a predetermined position, the structure is subjected to a significantly large vertical bending moment during towing, so the design cross section must be made large, which is disadvantageous in terms of stress.

Therefore, if the structure is divided into an appropriate number of units in advance and the individual divided bodies are joined together at sea, the above problem can be solved. The sea conditions such as wave pressure, wind pressure, and tidal currents are even more severe than those on the seabed (conventional bonding methods that utilize water pressure on the seabed are not used, so these harsh construction conditions can be overcome and high precision, There is a demand for the development of an offshore joining method that is highly efficient and economical.

In particular, with the construction of offshore airports, maritime cities, offshore nuclear power plants, offshore Plato bases, etc. predicted to occur in the near future, there is a need for the development of construction methods that can economically and easily construct such large offshore structures. There are some that are extremely expensive.

In response to such demands, the present invention constructs large-scale offshore structures by joining concrete floating boxes, which have been divided into an appropriate number of units in advance, to each other using prestressed steel wires at sea. The purpose of this invention is to construct floating bodies at sea through a consistent and continuous process, and the purpose of this invention is to construct a temporary construction process from pulling the floating body to temporarily fixing it. The purpose of the present invention is to provide a joining method that allows the user to select either a PC steel wire or other steel wire as appropriate.It is also an object of the present invention to provide a joining method that can be performed by dry work or all of a series of joining steps. Furthermore, an object of the present invention is to provide a joining method that is easy to manage and has high safety.
Furthermore, it is an object of the present invention to avoid being restricted by the scale of offshore structures or the capacity of the dog. It is an object of the present invention to provide a joining method that is compatible with any method of joining, and a further object of the present invention is to make the cross-sectional shape of a marine structure economical.

In other words, the present invention provides a concrete float formed by opening steel wire holes 12.12a and 12b in the joint end faces 3 and 4 provided with the facing members 5 and 6, as in the illustrated embodiment. The floating boxes 1 and 2 are floated to a predetermined ocean position by disposing a water stop member 11 on the joint end faces 3, and the floating boxes 1 and 2 are positioned so that the joint end faces 3 and 4 face each other. After that, at least the upper and lower steel wire sheath holes 12a between the floating boxes 1 and 2 are opened.

12b is stretched with PC steel wires i3a, 13b or other steel wires, and the two ends of the wire are brought together by hand, and the joining end surfaces 3 and 4 are brought together through the facing members 5 and 6 while being gradually tensioned, After the floating boxes 1 and 2 have been temporarily fixed in their proper positions, the accumulated water between the joint end faces is drained and mortar is injected between the joint end faces, and then the relative joint end faces 3.4 are P in each sheath hole 12 facing the
The C steel wire 13 is inserted into the PC steel wires 13, 13a.

The present invention relates to a method for joining concrete floating boxes at sea, which is characterized in that the floating boxes 1.2 are joined together by applying a constant tension to the concrete floating boxes 13b.

Embodiments of the invention will be described with reference to the drawings.

Figures 1 and 2 are a side view and a front view, respectively, showing a part of a concrete floating box manufactured by dividing a predetermined marine structure into appropriate units on a dock or on land. On the joint end surfaces 3 and 4 of the body 1°2,
Two cone-shaped facing members 5 and 6 are provided facing each other.

The mating member 5 on the end face 3 is a convex fitting guide, and the mating member 6 on the end face 4 is a concave fitting guide. When they are brought together, the end faces 3 and 4 are brought together at their proper positions.

A reinforcing material such as a steel plate, synthetic rubber, or synthetic resin is applied to the surface of this mating member.

In the illustrated example, two facing members are provided, but the number may be increased or decreased as appropriate.

Further, a drain port and a mortar injection port are appropriately provided on the joint end surface, and the other end is opened to the outer surface or inner surface of the floating box (not shown).

Furthermore, on the joint end surface 3, there is a water stop member 1 in double layer except for the upper end.
1 and 11 are arranged.

Further, the upper plate, upper plate, and side plate of the floating boxes 1 and 2 have a plurality of steel wire sheath holes 12.12a and 1 at opposing positions, respectively.
It passes through 2b.

The steel wire sheath holes 12a and 12b provided in the upper and lower parts are PC
Pulling the floating boxes together by inserting the steel wires 13a and 13b,
Use it for temporary fixing, or pull the steel wire from both ends,
As a means for applying further tension, for example, a jack (not shown) is installed inside the floating box.

In addition, when the floating box is floated in the ocean, a backing through which a steel wire can be inserted is provided at the end face hole opening of the sheath hole 12b at the portion below the water line to prevent seawater from entering the floating box. To prevent.

Furthermore, the other sheath holes 12 are provided with removable caps on their inner surfaces, and backings are provided around the end holes to prevent water from entering the floating box and to prevent mortar from entering between the end surfaces. This is to prevent the injection agent from seeping into the sheath hole (not shown).

FIG. 3 and FIG. 4 show another embodiment, in which four facing members 5 and 6 are provided on the joint end surface 3, and a water stop member 1 is provided.
Reference numeral 1 is disposed all over the periphery of the joint end surface 3, and air vent holes (not shown) are provided as appropriate.

The process of joining the floating box 1 and the floating box 2 will be explained with reference to FIGS. 5 to 8.

First, the floating boxes 1 and 2 are floated on the sea and towed to a predetermined position, and positioned so that their joint end surfaces 3 and 4 face each other (FIG. 5).

Next, the opposing sheath holes 12a and 12b of the end face
PC steel wires 13a and 13b are respectively inserted through them and stretched between the floating boxes 1.2.

The use of coated steel wire for this PC steel wire is advantageous in that it can prevent invasion through the sheath hole and corrosion by seawater.

In order to stretch the steel wire between the floating boxes, for example, first the steel wire is inserted into the floating box 1 and its tip is made to protrude above the sea.
A rope is inserted into the floating box 2 and its tip is connected to the tip of a steel wire that is inserted into the floating box 1 and protrudes above the sea, and then the other end of the rope is inserted from the side of the floating box 2. Attract.

Next, both ends of the steel wires 13a and 13b are connected to jacks provided inside the floating boxes 1 and 2, respectively, and the steel wires are pulled together by hand.The floating boxes 1 and 2 are then pulled together. Bring them close together.

As the floating boxes 1 and 2 approach each other, the mating members 5 and 6, which are provided opposite to each other on the end faces 3.4, come into contact with each other, and either a convex fitting guide or a concave fitting guide is formed. The end faces 3 and 4 are finally brought into contact with each other while maintaining their normal positions (FIG. 6).

Therefore, when the tension of the steel wires 13a and 13b is further increased, the respective peripheral surfaces 20 of the facing members 5 and 6 become pressure-bearing surfaces and are crimped together, as shown in FIGS. 9a and 9b, and the floating box 1 ,2
are temporarily fixed, and at the same time, the water stop members 11, 1 on the end surface 3 are temporarily fixed.
1 is crimped, and between the end faces 3.4, the water stop members 11, 11
Water is stopped in the space surrounded by the water (Figure 7).

In this embodiment, the peripheral surface of the mating member was used as the pressure-bearing surface, but the pressure-bearing surface may be provided on any part of the end surfaces 3 and 4. A pressure bonding member may be provided to serve as a water stop member and a pressure bearing surface.

This completes the temporary construction process from pulling the floating box to temporary fixing.

Next, the water stop members 11 and 1 between the end surfaces 3 and 4 of the floating boxes 1 and 2 are
The accumulated water in the space surrounded by 1 is discharged from a drain port (not shown), and mortar is poured into the space from an injection port (not shown).

In addition to cement mortar, various adhesives may be injected.

After the mortar has hardened, the opposite sheath holes 12 (those 12a, 1 through which the PC steel wire has already been inserted) on the end faces 3°4 are opened.
2b), and its both ends are connected to jacks provided inside the floating boxes 1 and 2, and the jacks apply a constant tension to the PC steel wires 13, 13a, and 13b. Once fixed, the floating boxes 1 and 2 are joined together with a predetermined strength (FIG. 8).

In the embodiments shown in FIGS. 3 and 4, substantially the entire surfaces of the joint end surfaces 3 and 4 are surrounded by the water stop member 11, creating a sealed space.

Therefore, when pouring mortar after draining the space, air is discharged using an air vent hole (not shown) as appropriate.

In the above embodiment, the temporary construction process from pulling the floating box to temporary fixing is carried out using a PC steel wire inserted into the floating box in advance, and the temporarily fixed floating box is finally integrated into one piece. Since it can be used as is when joining, it is extremely economical as it saves labor, construction time, materials, etc. compared to the case where temporary construction work is performed separately.

On the other hand, the temporary construction process can also be performed using steel wires (such as ordinary wires) other than PC steel wires.

In this case, the sheath holes through which the steel wire is inserted are appropriately provided at the upper and lower parts of the floating box, separately from the sheath holes for the PC steel wire.

To prevent seawater from entering the floating box through the sheath hole, use a backing that can be inserted through the steel wire, or
Either insert the lower steel wire 13a into the side plates of the floating box and have both ends protrude above the deck of the floating box as shown in Figures 11a and b, or as shown in Figure 11a and b. Pressurized air chambers 30, 30 are provided inside the floating box, and pressurized air corresponding to the water pressure below the water line is injected.

As described above, the present invention allows the offshore joining of concrete floating bodies to be consistently constructed in a continuous process.

Either PO steel wire or other steel wire can be selected as appropriate for the temporary installation process from pulling the floating box to temporary fixing, so it can be used for all offshore structures regardless of the construction scale or strip structure. Applicable to construction.

In addition, since all construction is done by dry work, work management is easy and there is no danger, and it also has the advantage of being able to construct large-scale offshore structures efficiently and inexpensively.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing a part of an embodiment of a concrete floating box according to the present invention, FIG. 2 is a view taken along the line A-A in FIG. 1, and FIG. FIG. 4 is a vertical cross-sectional view showing another embodiment, and FIG. 4 is a diagram along the line B-B in FIG. The figures show a part of the joined end surface of a temporarily fixed floating box, and Figure 10a is a cross-sectional view thereof, Figure 10 is a view taken along line C-C in Figure 10a, and Figure 10a is
. Figures b and 1-a and 1-b are respectively other embodiments of the present invention. In the figure, 1 and 2 are concrete floating boxes, 3 and 4 are joint end surfaces, 5 and 6 are facing members, 11 is a water stop member, 12, 12
a, 12b are steel wire sheath holes, 13° 13a, 13b are P
It is C steel wire.

Claims (1)

[Claims] 1. A concrete floating box formed by opening a steel wire sheath hole in the joint end face provided with a matching member is floated to a predetermined ocean position by disposing a water stop member on the joint end face. , After positioning the floating boxes so that the joint end faces face each other, a PC steel wire or other steel wire is stretched through at least the upper and lower steel wire sheath holes between the floating boxes. The floating box is brought together from both ends, and the joined end faces are brought together through the joining member while being gradually tightened, and the floating box is temporarily fixed in the correct position. After draining the accumulated water and injecting mortar between the end faces, insert a PC steel wire into the opposing sheath holes of the joint end face to apply a constant tension to the PC steel wire, thereby removing the floating box. An offshore joining method for concrete floating bodies that is characterized by joining the bodies together. 2. The offshore joining method of concrete floating boxes according to claim 1, characterized in that the concrete floating boxes have a part of the joining end surface as a bearing surface.