JPH0211688B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a gravity type embankment body.

Conventional gravity-type embankments (ship caisson type, concrete caisson type, steel caisson type, etc.) form a foundation mound 9 on the submarine ground 10 as shown in Fig. 1, and a caisson 12 is placed on top of the foundation mound 9. It was constructed in this manner. However, due to the ground subsidence phenomenon (indicated by the solid line in the figure), the following problems occurred.

(1) Construction will take longer because structures above the levee body (cranes, winches, lighting lights, etc.) cannot be constructed until the subsidence phenomenon has finished to a certain extent.

(2) If construction is to be carried out within a limited construction period (subsidence is continuing), it will be necessary to repair the upper structure of the levee body after settlement is complete. Additionally, maintenance and management will be necessary during the ongoing subsidence, which will incur maintenance and repair costs.

(3) Due to the subsidence phenomenon, it is impossible to construct the required structure on top of the embankment body.

The present invention aims to solve the above-mentioned problems, and aims to provide a gravity-type embankment body that does not require maintenance or repair of the upper structure of the embankment body even if the seabed ground and foundation mound sink.

For this reason, the gravity type embankment body of the present invention has a gravity type embankment body in which a caisson is placed on a foundation mound created on the seabed surface, and a guide pipe provided vertically through the caisson, and a guide pipe provided vertically through the caisson. It is characterized by having a foundation pile that is loosely fitted into the seabed and whose lower end is driven into the seabed.

A gravity-type embankment as an embodiment of the present invention will be explained below with reference to the drawings. Fig. 2 is a perspective view, Fig. 3 is a cross-sectional view, and Fig. 4 is an enlarged view of the vicinity of the foundation pile in Fig. 3. 1 is a crane concrete girder (a steel girder or the like is also acceptable), and 2 is a guide pipe such as a steel pipe pile, a steel duct, a steel box, or a synthetic resin pipe provided in the hull caisson 12. 3 is a foundation pile made of steel pipe piles, H steel, etc.; 4 is the upper hull deck;
5 is the hull vertical bulkhead, 6 is the hull outer plate, 7 is the hull bottom outer plate, 8 is the filling soil, 9 is the foundation mound, 10 is the submarine ground layer, 11 is the base layer, 13 is the upper concrete, 14 is the pavement, 15 is a buffer material, and 16 is a crane rail.

Next, we will describe the construction procedure for this gravity-type embankment body.

(1) A predetermined number of guide pipes 2 are installed in the hull caisson 12 in advance by welding or the like in the factory.

(2) Towing the hull caisson 12 to a predetermined sea area,
The foundation piles 3 are driven to the foundation layer 11 on the seabed using a pile driver (not shown) (in some cases, the foundation piles 3 may be driven after excavating the ground in advance). At that time, the inner surface of the guide pipe 2 and the foundation pile 3
Ensure sufficient space so that it does not come into contact with the outside surface of the

(3) Connect the head of foundation pile 3 to crane concrete girder 1.

(4) In order to separate the foundation pile 3 and the hull caisson 12, cover the surface of the crane concrete girder 1 with a buffer material 15 made of elastite, asphalt, etc.

Therefore, according to this embodiment, since the foundation pile 3 and the hull caisson 12 are separated, synergistic sinking of the embankment upper structure due to the sinking of the foundation mound 9, seabed ground layer 10, and hull caisson 12 is prevented. be able to.

As described above, according to the gravity-type embankment of the present invention, the foundation piles are loosely fitted into the guide pipes and driven into the seabed, so even if the caisson sinks, the foundation piles will remain tight together with the caisson. It never happens. Further, even if the caisson moves horizontally due to external force such as wave force or seismic force, the horizontal force will not be transmitted to the foundation pile and it will not be displaced in the horizontal direction.

Therefore, it is possible to construct the upper structure of the levee body without the cessation of the caisson subsidence phenomenon, and the construction period of the levee body itself can be greatly shortened. This has the effect of eliminating the need for maintenance, management, and repair of structures.

Furthermore, if it becomes necessary to replace the foundation pile due to corrosion, or if you want to increase the diameter of the foundation pile, the foundation pile can be easily pulled out because it is loosely fitted into the guide pipe. There is also this effect.

[Brief explanation of drawings]

Figure 1 is a side view of a conventional gravity-type embankment;
Figures 1 to 4 show a gravity embankment body as an embodiment of the present invention, with Figure 2 being a perspective view, Figure 3 being a cross-sectional view, and Figure 4 being an enlarged view of the vicinity of the foundation pile. 1... Crane concrete girder, 2... Guide pipe, 3... Foundation pile, 9... Mound, 10... Seabed ground layer, 11... Foundation layer, 12... Hull caisson.

Claims (1)

[Claims] 1. In a gravity-type embankment body consisting of a caisson placed on a foundation mound built on the seabed surface, a guide pipe is installed vertically through the caisson, and the lower end is fitted loosely into the guide pipe. A gravity-type embankment body characterized by being equipped with a foundation pile driven into the seabed.