JPH0577330U - Cylindrical caisson joint - Google Patents

Abstract

(57) [Summary] [Purpose] Can be constructed at sea without being affected by weather conditions,
Further, it provides a joint portion of a cylindrical caisson which is easy to prevent the outflow of the filled soil and has excellent workability and economy. [Structure] Cylindrical caisson 1 is a reinforced concrete bottom plate 2
And a steel cylindrical body 3. On the outer surface of the steel cylindrical body 3, a steel connecting wall 6 having a T-shaped cross section which constitutes a front wall and a rear wall of the joint portion is provided. The steel connecting walls 6 of the adjacent cylindrical caisson 1 are butted against each other, and the rubber waterproof material 7 attached to the tip of one steel connecting wall 6 is crushed to form a water-stopped space in the joint portion. Filling 5 and 8 are performed in the steel cylindrical body 3 and the joint portion surrounded by the steel connecting wall 6, respectively.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a caisson structure used as a breakwater, a seawall harbor, and an offshore structure, and more particularly to a structure of a cylindrical caisson joint in which a reinforced concrete bottom plate and a steel cylinder are integrated.

[0002]

[Prior Art]

 Conventionally known caisson structures for breakwaters and seawalls are those using steel cylinders such as steel plate cells, and reinforced concrete caissons.

Further, Japanese Patent Laid-Open No. 1-271524 discloses a cylindrical caisson (hereinafter simply referred to as a cylindrical caisson) in which a cylindrical side wall made of a steel plate or the like constituting a caisson body and a bottom plate made of reinforced concrete are integrated. Has been done.

7 and 8 show an example of the structure of a conventional joint portion of the cylindrical caisson 1. The cylindrical caisson 1 in this example is formed by integrating a steel cylindrical body 3 on the upper surface of a reinforced concrete bottom slab 2 having a rectangular planar shape. The steps until the cylindrical caisson 1 is installed in the construction of a breakwater are as follows. ..

The cylindrical caisson 1 is manufactured on land.

The cylindrical caisson 1 is floated and transported by sea, and installed on a prefabricated seabed mound.

Inside each of the installed cylindrical caisson 1 is filled 5 with earth and sand.

Conventionally, thereafter, the adjacent cylindrical caissons 1 are connected to each other by an arc-shaped front wall and an outer wall (hereinafter, referred to as an arc 16) made of a steel plate called an arc. Following the above steps, the procedure for installing the arc 16 is as follows.

The arc 16 is transported by sea.

The end (male joint) of the arc 16 is inserted from above into the joint member 4 (female joint) attached to the outer surface of the cylindrical caisson 1 by welding or the like, and the joint member 4 is fitted thereto.

Filling 8 with earth and sand is performed between the arcs 16 forming the front wall and the rear wall.

[0012]

[Problems to be solved by the device]

 The method of connecting the adjacent cylindrical caissons 1 by the arc 16 described in the section of the related art has the following problems.

The arc 16 installed for the purpose of integrating the cylindrical caisson 1 is installed by sea construction after the completion of the installation of the cylindrical caisson 1, and is therefore easily affected by waves and wind.

In order to stabilize the structure, it is necessary to add the filling sand immediately after installing the main body of the cylindrical caisson 1 and the arc 16, respectively, but in the case of a small-scale cylindrical caisson, It is uneconomical because the amount of filling sand that is input is less than the loading amount of a ship that carries sand, and waiting for work occurs.

When a gap is created between the reinforced concrete bottom slabs 2 of each adjacent cylindrical caisson 1 due to a problem in construction accuracy, in order to use earth and sand for filling the inside, consider the outflow of the filling sand from the gap. Will have to. For this reason, it is uneconomical to take measures such as injecting mortar into the bottom surface of the filling.

The present invention is intended to solve the above-mentioned problems in the conventional cylindrical caisson, particularly in the joint portion thereof.

[0017]

[Means for Solving the Problems]

 In the present invention, the front wall and the rear wall for connecting the cylindrical caissons 1 are projected from the outer surface of the steel cylindrical body 3 of the adjacent cylindrical caisson 1, respectively, and the tips are abutted to each other via the water blocking material 7. It is composed of a pair of steel connecting walls 6. The steel connecting wall 6 can be joined to the outer surface of the steel cylindrical body 3 in advance on land (including inside the dock) by welding or through an appropriate joint member.

The water blocking material 7 is made of rubber or the like, and may be, for example, a rubber gasket used at a joint portion of a submerged box or the like. This water blocking material 7 is attached to at least one of the ends of the steel connecting walls 6, and high water blocking performance can be obtained in a state where the adjacent steel connecting walls 6 are butted against each other. It should be noted that it is conceivable that the tip of the steel connecting wall 6 has a T-shaped cross section in order to attach the water blocking member 7 and improve the water blocking property thereof.

Further, in order to make the water blocking property in the joint portion more complete, it is conceivable to place underwater concrete or the like as a filling material in the joint portion surrounded by the steel connecting wall 6.

[0020]

[Action]

 When using a cylindrical caisson as a revetment, it is necessary to connect adjacent cylindrical caisson to prevent the outflow of backfill sand. In addition, in order to increase the quietness of the breakwater, it is necessary to connect the breakwater in the same way to prevent water from entering and exiting through the breakwater.

In the present invention, by using the connecting wall 6 provided on each of the adjacent cylindrical caissons 1 and the water blocking material 7 interposed therebetween, the following advantages can be obtained. is there.

The step of inserting the arc 16 into the joint member 4 of the cylindrical caisson 1 at the time of installing the conventional arc 16 is replaced with the step of attaching the steel connecting wall 6 and the water blocking material 7 to the cylindrical caisson 1 by land work. Therefore, it is possible to reduce the influence on the process due to the weather conditions at sea.

According to the present invention, the filling 5 inside the steel cylindrical body 3 of the cylindrical caisson 1 and the inside of the connecting portion (between the front wall and the rear wall formed by the steel connecting wall 6 and the water blocking member 7) The packing 8 can be performed at the same time, and the process can be shortened.

When earth and sand are used for the filling 8 of the connecting portion, the water stopping material 7 made of rubber or the like is continuously provided to the position of the reinforced concrete bottom slab 2 to prevent the outflow of the earth and sand between the adjacent reinforced concrete bottom slabs 2. Can be prevented.

[0025]

【Example】

 Hereinafter, the present invention will be described based on illustrated embodiments.

FIG. 1 and FIG. 2 show an outline of a joint portion in one embodiment in which the present invention is applied to a breakwater as a caisson structure.

As a construction procedure in this embodiment, first, in a yard or a dock on the ground, a steel connecting body 6 having a T-shaped horizontal cross section and a steel waterproofing member 6 having a horizontal cross section are attached to a steel cylindrical body 3 constituting a main body of a cylindrical caisson 1. Attach 7. The length of the steel connecting wall 6 in the direction of the breakwater extension is such that the end of the reinforced concrete bottom slab 2 is aligned with the T-shaped tip surface. Further, the dimension of the steel connecting wall 6 in the height direction is from the upper end of the steel cylindrical body 3 to the upper end of the reinforced concrete bottom plate 2.

As an example of the approximate dimensions of the concrete bottom slab 2 and the steel cylinder 3, the bottom slab thickness is 50 to 100 cm, the steel plate thickness of the steel cylinder 3 is 0.8 to 2.0 cm, and the diameter of the steel cylinder 3 is 5 It is about 20 m.

The rubber waterproof material 7 is attached to the tip of the steel connecting wall 6 in the vertical direction. FIG. 3 shows an example of a compression type water blocking material as an example of the rubber water blocking material 7. The compression-type waterproof material is crushed between the ends of a pair of steel connecting walls 6 that abut the rubber pipes between adjacent cylindrical caissons, as shown in Fig. 4. Can be filled up and water can be stopped. In addition, as the rubber waterproofing material 7, a material using water-swelling rubber can be used.

It should be noted that the rubber waterproofing material 7 does not necessarily have to be provided on both of the steel connecting walls 6 that collide with each other, but it may be attached to the leading end of the steel connecting wall 6 of at least one of the adjacent cylindrical caissons 1. Good.

Regarding the dimension of the rubber waterproofing material 7 in the height direction, from the upper end of the steel connecting wall 6 to the upper end of the reinforced concrete bottom slab 2, and as shown in FIG. It is considered to be up to the bottom. In the case of reaching the upper end of the reinforced concrete bottom slab 2, the filling 8 may flow out from the gap between the bottom slabs 2, so the filling 8 between the front wall and the rear wall formed by the steel connecting wall 6 Is better to use underwater concrete. Alternatively, the bottom plate 2 may be appropriately water-stopped (such as pouring of underwater concrete), and then earth and sand may be added to the upper part thereof.

FIG. 6 shows an outline of a caisson structure installed on the seabed mound 9 using the joint portion according to the present invention. A cylindrical caisson 1 manufactured on land, to which a steel connecting wall 6 and a water blocking material 7 are attached, is transported by sea and sequentially sunk on a prefabricated seabed mound 9, and the cylindrical caisson 1 is lined up. At this time, water blocking is performed by the water blocking material 7. The filling can be performed at the same time in the steel cylindrical body 2 of the main body of the cylindrical caisson 1 and the steel connecting wall 6 forming the joint portion. Further, in the steel connecting wall 6, by placing underwater concrete as a filling material, a more complete waterproof structure can be obtained.

[0033]

[Effect of the Invention] The conventional process of inserting the arc into the joint member of the cylindrical caisson at sea can be replaced with the process of attaching the steel connecting wall and the water blocking material to the cylindrical caisson by land work. The influence of weather conditions on the process can be reduced.

The filling of the cylindrical caisson and the filling of the joint portion can be performed at the same time, and the process can be shortened.

As compared with the conventional type using an arc, it is easier to prevent the outflow of earth and sand as a filling material.

[Brief description of drawings]

FIG. 1 is a plan view showing an outline of a joint portion in an embodiment of the present invention.

FIG. 2 is a front view corresponding to FIG.

3A and 3B show an example of the shapes of a connecting wall and a rubber waterproofing material, in which FIG. 3A is a front view and FIG. 3B is a plan view.

4 (a) and 4 (b) are plan views showing the principle of water blocking by a rubber water blocking material.

5A and 5B show an embodiment in which the water blocking material is extended to the bottom plate portion, FIG. 5A is a front view, and FIG. 5B is a sectional view taken along line AA.

FIG. 6 is a perspective view showing an outline of a caisson structure installed on a submarine mound using the joint part according to the present invention.

FIG. 7 is a plan view showing an outline of a conventional joint portion of a cylindrical caisson.

FIG. 8 is a front view corresponding to FIG.

[Explanation of symbols]

1 ... Cylindrical caisson, 2 ... Reinforced concrete bottom plate, 3 ...
Steel cylindrical body, 4 ... Joint member, 5 ... Filled, 6 ... Steel connecting wall, 7 ... Water blocking material, 8 ... Filled, 9 ... Subsea mound, 16 ...
arc

Claims (2)

[Scope of utility model registration request] 1. A front wall for arranging a plurality of cylindrical caissons in which a reinforced concrete bottom slab and a steel cylindrical body as a caisson body are arranged side by side, and forming a joint between the steel cylindrical bodies of adjacent cylindrical caissons, and In a joint portion of a caisson structure connected by a rear wall, the front wall and the rear wall respectively project from the outer surface of the steel cylindrical body of the adjacent cylindrical caisson, and a pair of ends are butted through a water blocking material. 2. The joint portion of the cylindrical caisson, characterized in that the water blocking member is attached to at least one tip of the pair of steel connecting walls. 2. The joint portion of a cylindrical caisson according to claim 1, wherein underwater concrete is placed as a filling material between the front wall and the rear wall.