JPH05141191A - Submerged caisson final connecting method - Google Patents

Abstract

PURPOSE:To provide a submerged caisson final connecting method that is less in underwater work by a diver, and easy in quality control and safety management, and beside, excellent in workability even in the abyssal zone. CONSTITUTION:In this method, a double form 1, whose both ends between an inner form 2 and an outer form 3 concentrically set up are closed by two flexible forms 4a and 4b, is used. This double form 1 is inserted into a joint clearance 11 between two final submerged caissons 8a and 8b being connected. Underwater concrete 13 is placed in space between the inner form 2 and the outer form 3, bulging the flexible forms 4a, 4b outward, and these forms 4a, 4b are stuck close to both joint end faces 10a, 10b of the final submerged caissons 8a, 8b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a final submerged box in which submerged tunnels are formed by connecting submerged boxes one after another or connecting the final submerged box and the submerged tunnel shaft using submerged concrete. It relates to the connection method.

[0002]

2. Description of the Related Art A conventional submerged box final connection method using underwater concrete is carried out by surrounding a portion of the submerged box to be connected with a formwork, and pouring underwater concrete into the box.

[0003]

However, in the conventional submerged box final connection method using such underwater concrete, the assembly of the formwork is an underwater work by the diver, and safety management, workability, and quality control are considered. There are many problems, especially in deep water. In addition, since underwater concrete acts as a water blocking material during construction, there is a problem in quality control of concrete.

It is an object of the present invention to provide a submerged box final connection method which requires less diving work by a diver, facilitates quality control and safety control, and has good workability even in deep water.

[0005]

The features of the present invention for attaining the above-mentioned object are that the final submersible boxes which are submerged on the mutual sides, or the bulkheads of the final submerged box and the submerged tunnel shaft respectively. In the submerged box final connection method that liquid-tightly joins the joint gaps between the two joint end faces that are closed and opposed to each other, a double cylinder structure is formed by the cylindrical inner and outer molds. Then, using a double mold whose both ends are closed by a flexible mold, the double mold is set in the joint gap, and the inner mold and the outer mold of the double mold are set. Underwater concrete is cast between the formwork and the flexible formwork is inflated by the pressure of the underwater concrete so as to be in close contact with the joint end surface of the connection partner.

[0006]

When a double formwork having such a double cylinder structure as an inner formwork and an outer formwork and both ends of which are closed by flexible formwork is used, When underwater concrete is cast between the inner and outer molds, the flexible molds on both sides bulge outward by the underwater concrete and come into close contact with the joint end face of the connection partner.

Therefore, the underwater work by the diver is reduced. In addition, the quality of the underwater concrete can be prevented from directly contacting with water, and the deterioration of quality can be prevented.

[0008]

EXAMPLE FIG. 1 shows an example of a double formwork 1 used in this example. The double formwork 1 has a cylindrical steel inner formwork 2 and a steel outer formwork 3 arranged coaxially, and both ends between these formwork 2 and 3 are made of cloth-permeable liquid. Each of the flexible molds 4a and 4b has a structure that is closed. Further, both molds 2 and 3 are held by a spacer 5 so that the distance between them is constant.

Next, a method of finally connecting the submerged box of this embodiment using the double mold 1 will be described with reference to FIGS.

First, as shown in FIG. 2, submerged box tunnels 7a and 7b are formed on the bottom of the water 6 from the left and right by connecting the submerged boxes, and the tip openings of the final submerged tubes 8a and 8b at the respective ends are bulk. The heads 9a and 9b are respectively closed, and the joint end face 10 is formed between the two final submersible boxes 8a and 8b.
A joint gap 11 is formed between a and 10b.

The double formwork 1 described above is hung in the joining gap 11 by a crane or the like.

Next, as shown in FIG. 3, underwater concrete 13 is poured between the inner mold 2 and the outer mold 3 through the concrete supply pipe 12 from above the water.

When the underwater concrete 13 is cast, the flexible molds 4a, which close both ends of the inner mold 2 and the outer mold 3,
4b bulges outward, and the final buried pipes 8a, 8 on both sides
It is brought into close contact with the joint end faces 10a and 10b of the b.

In this state, as shown in FIG. 4, the water blocking material injection hole 14 provided in advance in the final submerged pipes 8a, 8b.
Water-stopping is performed by injecting a water-stopping material into the gap between the joint end surfaces 10a, 10b and the flexible molds 4a, 4b via a and 14b.

Next, as shown in FIG. 5, the water 15 between the bulkheads 9a and 9b is drained into the drain holes 16 of the bulkhead 9b.
The inside of the double formwork 1 is used as a dry space.

Next, as shown in FIG. 6, the bulkhead 9
The a and 9b are removed, and the cast-in-place concrete 17 is poured in the dry space on the inner periphery of the double formwork 1.

By selecting the liquid opening ratio of the liquid-permeable flexible molds 4a and 4b, the cement milk component of the underwater concrete can be exuded to the outer surface side, and the cement milk that has exuded can be used for joining. End faces 10a, 1
Liquid tightness with respect to 0b can be provided, and in this case, it is not necessary to inject the water blocking material from the water blocking material injection holes 14a and 14b.

Further, the present invention can be similarly applied to the connection of the junction gap between the final submerged pipe of the submerged box tunnel and the submerged tunnel pit.

[0019]

As described above, in the submerged box final connecting method according to the present invention, the double mold having a structure in which both ends between the inner mold and the outer mold arranged coaxially are closed by the flexible mold. Using a frame, place this double form in the joint gap between the joint end faces of the mating partners to be connected, and in that state place underwater concrete between the inner and outer forms, and press the pressure of this underwater concrete. Since the flexible molds on both sides are outwardly inflated and brought into close contact with the joining end surface of the joining partner, the following effects can be obtained. (B) By using a double mold, diving work is almost eliminated and safety and workability are improved. (B) Even if the axis of the box is not aligned or the joint end faces are not parallel, the flexibility of the flexible form facilitates close contact with the joint end faces. (C) Since the underwater concrete is not directly exposed to water, quality can be improved. (D) By using a double mold, the process can be shortened and the construction period can be shortened.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a double mold used in the present invention.

FIG. 2 is a vertical cross-sectional view showing a process of inserting a double mold into a bonding gap in this embodiment.

FIG. 3 is a vertical cross-sectional view showing a step of placing underwater concrete on a double mold in this embodiment.

FIG. 4 is a vertical cross-sectional view showing a step of injecting a water blocking material into the gap between the double mold and the connection partner in the present embodiment.

FIG. 5 is a vertical cross-sectional view showing a process of draining the double mold in the present embodiment.

FIG. 6 is a vertical cross-sectional view showing a step of placing in-situ concrete on the inner surface of the double mold in the present embodiment.

[Explanation of symbols]

 1 Double Form 2 Inner Form 3 Outer Form 4a, 4b Flexible Form 5 Spacer 6 Water Bottom 7a, 7b Submerged Box Tunnel 8a, 8b Final Submerged Pipe 9a, 9b Bulkhead 10a, 10b Joining End Face 11 Joining Gap 12 Concrete supply pipe 13 Underwater concrete 14a, 14b Water blocking material injection hole 15 Water 16 Drain hole 17 In-place concrete

Claims (1)

[Claims] 1. A joining gap between joining end surfaces of two or more final submerged boxes that are submerged on either side, or between the final submerged box and the submerged tunnel shaft that are closed by bulkheads and face each other. In a submerged box final connection method for liquid-tightly connecting, a double cylinder structure is formed by a cylindrical inner mold and an outer mold, and both ends of these molds are closed by a flexible mold. Using a double formwork that is present, set the double formwork in the joint gap, place underwater concrete between the inner formwork and the outer formwork of the double formwork, and press the pressure of the underwater concrete. 2. The final connection method for a submerged box, characterized in that the both flexible molds are inflated and brought into close contact with the joint end surface of the connection partner.