JPH0465171B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for constructing a caisson that enables the economical construction of a huge caisson by joining conventional regular-sized concrete caissons over water. be.

[Prior art]

Traditionally, caissons used for breakwaters and other underwater structures are made on land in a caisson yard or dry dock, then towed out to sea and installed in a predetermined location, or in some cases simply installed at sea. It is known that it is constructed by

However, the conventional method of constructing a huge concrete caisson has been problematic in that it requires a vast caisson yard or the construction of a new large dry dock.

[Purpose of the invention]

Therefore, the present invention solves the above-mentioned conventional problems,
The object of the present invention is to provide a caisson construction method that enables economical construction of a gigantic caisson by repeatedly overturning regular-sized concrete caissons on water.

[Structure of the invention]

That is, in the caisson construction method of the present invention, a concrete side wall is poured onto the top of a concrete caisson that is made on land and floated on water, and after the upper opening of the side wall is sealed with a lid,
Ballast water is poured eccentrically into the concrete caisson and it is turned over, and in this state, a concrete side wall is poured onto the top of the other side of the concrete caisson, and the opening is sealed again with a lid. This method is characterized in that the above construction method is repeated depending on the size of the caisson to construct a caisson of the required size.

〔Example〕

An embodiment in which the caisson construction method of the present invention is applied will be described below with reference to the drawings. First, as shown in Fig. 1, a concrete caisson 2 of normal size is constructed in a dry dock 1, and after completion Remove the gate 3, float it above seawater W as shown in Figure 2, tow it out to a sufficiently deep body of water, or even a sea area, moor it with an anchor, etc., and place it on top of the caisson 2. Using a sliding platform or other suitable formwork, the concrete side wall 4 is joined as shown in Figure 3.
At this time, as shown at 5 and 5', ballast water is injected while being adjusted to maintain balance.

Furthermore, once the side wall body 4 is completed, its upper opening is sealed watertight with a concrete lid 6, and then, as shown in Fig. 4, ballast water 5' is injected into only one side to increase the deviation. Then, invert the caisson itself 90 degrees as shown by arrow T to bring it to the state shown in Figure 5.

In order to further increase the size of the caisson itself in this state, the ballast water 5 is discharged from the vertically unstable state shown in Fig. 6-A which shows the same state as Fig. 5 and Fig. 6B- which is a side view thereof. Increase the buoyancy and invert it by 90 degrees as shown by the arrow T' to bring it to the horizontally long and stable state shown in Figures 7-A and 7-B. Inject ballast water 5 and maintain balance as shown in Figure 8-A. Then, as shown in Figure 8-B, the side wall 4' is joined with concrete and sealed with a lid 6', and the above steps are repeated according to the size of the caisson to form a huge caisson of the required size. Complete 8.

In addition, when towing the completed giant caisson 8, it is necessary to install a steel watertight lid etc. to maintain safety. This shows an example of a caisson 8 installed for a breakwater.The huge caisson 8 is placed on top of a rubble mound 10 formed on the seabed 11, and water is poured into the box to sink it. It is filled with sand or concrete, and then a superstructure 9 is placed on top to complete the breakwater.

〔Effect of the invention〕

Therefore, if the method of the present invention is adopted, a huge caisson can be constructed by repeatedly overturning a conventional concrete caisson on the water and joining each time. Once a caisson is manufactured, it can be made into a large size at sea, making it economical because conventional sized equipment, ie docks, can be used as is.

Further, even when the caisson is overturned, the ballast water used as ballast water is simply injected or drained eccentrically into the caisson, and there is an advantage that a crane ship is not required and the manufacturing cost is low.

[Brief explanation of drawings]

Figures 1, 2, 3, 4, and 5 are cross-sectional views illustrating the process of joining and overturning the side wall of a caisson in an embodiment to which the caisson construction method of the present invention is applied. , Figure 6-A, Figure 6-B,
Figure 7-A, Figure 7-B, Figure 8-A, Figure 8-B
Figures 9-A and 9-B are explanatory views of the process of connecting the side wall bodies to the caisson of Figure 5 to form a huge caisson, and then installing it as a breakwater, and Figure 6-B is a side sectional view of Fig. 6-A, and Fig. 7-
Figure B is a side sectional view of Figure 7-A, and Figure 8-B is a side sectional view of Figure 8.
- A side sectional view of figure 9-A, and figure 9-B of figure 9-A.
FIG. 2... Caisson, 4, 4'... Side wall body, 5,
5'...Ballast water, 6,6'...Lid, 8...Giant caisson, W...Sea water.

Claims (1)

[Claims] 1. After pouring a concrete side wall onto the top of a concrete caisson built on land and floating it above water, and sealing the upper opening of the side wall with a lid, ballast water is poured eccentrically into the concrete caisson. Fill the concrete caisson with water, turn it over, and in that state add a concrete side wall to the top of the other side of the concrete caisson, seal the opening again with a lid, and then apply the above method depending on the size of the caisson. A caisson construction method characterized by repeatedly constructing a caisson of required dimensions.