JPH0132330B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a protection device for multi-column foundations used for underwater bridge piers, etc.

The footings of multi-column foundations are often relatively thin and located above the water level. Therefore, there is a risk that the vessel will crawl under the footing. As a countermeasure against this problem, as shown in FIGS. 1 and 2, it is known that a large number of long protective members 9 are attached to the periphery of the footing 8 of the multi-column foundation so as to reach the water. However, in the case of this structural type, it is difficult to install the protection member 9 so that it has sufficient strength even if a ship collides with the lower part of the protection member 9, and the protection member itself is large-scale and the construction cost is high. In addition, if a ship destroys the protective members and moves forward, it will directly collide with the foundation piles, and if this phenomenon occurs, even if the multi-column foundation as a whole can withstand the collision force, the piles will be damaged. A single pile cannot withstand the impact force, and as a result, several piles may be damaged one after another, ultimately leading to the destruction of the entire foundation.

Furthermore, as shown in FIGS. 3 and 4, a separate protective structure 10 such as a cell structure or a pile structure may be installed in front or behind the multi-column foundation in a manner that is isolated from the multi-column foundation. is also known. but,
In this case, the resistance of the multi-column foundation cannot be used against the ship's collision force, and the protective structure must resist the ship's collision force alone, resulting in poor economic efficiency and structure. There is also the problem that the space for installing things becomes larger.

The object of the present invention is to provide a multi-column foundation protection device that advantageously solves the above-mentioned problems.

Next, the present invention will be explained in detail using illustrated examples.

5 to 8 show an embodiment of the present invention, in which a large number of pipe columns 1 are connected by connecting members 2 to form a steel jacket structure 3. A foundation pile 4 made of a steel pipe pile is inserted into each pipe column 1 and driven into the underwater ground 11, and mortar 12 is filled between the pipe column 1 and the foundation pile 4. A steel shim plate 13 is fitted between the upper end of the foundation pile 4, and the shim plate 13 is fixed to the pipe column 1, the foundation pile 4, or both by welding.

A large number of supporting vertical members 5 made of steel pipes with both ends closed are arranged at intervals around the jacket structure 3, and a plurality of annular protective beams 6 made of steel pipes surrounding each vertical member 5 are arranged at intervals in the vertical direction. The beam 6 and each vertical member 5 are connected to each other through a steel connecting member 14 interposed between them and fixed by welding, and each of the protective beams 6 and each vertical member 5 are connected to each other. A protection device 7 is constituted by each vertical member 5 attached via a member 14, and each pipe column 1 in the jacket structure 3 and the vertical member 5 facing it are interposed between them with bolts or They are connected via a steel connecting member 15 that is fixed by welding.

A buffer material 16 such as a liquid or granular material is filled in the beam 6 and in the vertical member 5 to buffer ship collision forces, and the buffer material 16 is filled with a buffer material 16 such as a liquid or granular material for buffering ship collision forces, and extends over the upper end of each pipe column 1 and the upper end of each foundation pile 4. Concrete footing 8 with multi-column foundation is being constructed.

When constructing the multi-column foundation protection device of the above embodiment, it is best to prefabricate it as much as possible, but generally speaking, the jacket structure and protection members are separated, and the pipes of the jacket structure are first constructed. The foundation pile is constructed using the pillar as a guide, and then the foundation pile and the pipe pillar are connected, and then the protective member is transported by a crane ship or the like and attached to the jacket structure.

When a ship collides with the protective beam 6, a large impact energy can be absorbed by the elastic deformation and plastic deformation of the steel pipes constituting the beam 6 and the steel pipes constituting the vertical member 5, and by the buffer material 16. can.

The filling of the cushioning material 16 is generally carried out on land, but it may also be carried out after the protective device 7 is attached to the jacket structure 3.

The dimensions and number of protective beams 6 and the dimensions and length of the vertical members 5 depend on the size of the target ship,
It is determined by considering collision energy, etc. Since the protective beam 6 is generally long, it is preferable to divide it into a straight part and a curved part, and to join them at the construction site by welding or flange joints.

When carrying out this invention, the protective device 7 may not be provided around the entire circumference of the jacket structure 3, but may be provided only in areas where there is a risk of a ship colliding, and the protective beam 6 and vertical member 5 may be made of materials other than steel pipes. A protective beam 6 having an arbitrary cross section may be used, and a rubber cushioning material may be attached to the outer surface of the protective beam 6. If the protection device has a buffering function, it is possible to further reduce the impact force applied to the multi-column foundation when a ship collides, and damage to the ship can be reduced.

A protective device unit may be constructed in which the protective device is divided into a plurality of units, for example, four or more in the circumferential direction of the jacket structure, and a joint using a flange and a bolt may be provided in the middle of the connecting member 15. In this way, in the event that the protective device unit is damaged,
The damaged guard unit can be easily replaced.

Alternatively, the entire jacket structure and the entire protective device may be manufactured on land, towed to the site by a crane ship, etc., and prefabricated at once. If such a construction method is adopted, on-site construction work can be carried out easily and quickly, resulting in many economic benefits.

According to this invention, a large number of tube columns 1 are connected to a connecting member 2.
Steel jacket structure 3 constructed by connecting
Each of the foundation piles 4 of the multi-column foundation is inserted into and fixed to each of the pipe columns 1, and each of the vertical members 5 is inserted into a large number of supporting vertical members 5 arranged at intervals in the circumferential direction of the jacket structure 3. A protective beam 6 arranged so as to extend over the outside of the vessel is attached to constitute a protective device 7, and each of the longitudinal members 5 is attached to the jacket structure 3, so that the ship cannot be attached to the protective device 7. In the event of a collision, the collision force can be transmitted to a large number of foundation piles 4 in the multi-column foundation via the jacket structure 3, thereby preventing some of the foundation piles in the multi-column foundation from being damaged. In addition, each foundation pile 4 in the multi-column foundation is reinforced with a jacket structure 3, and the entire structure becomes an integral structure that can strongly resist the collision force of a ship, and the protection device 7 has a jacket structure. A large number of vertical members 5 arranged at intervals in the circumferential direction of the object
and the protective beam 6 supported thereby, the protective device 7 is also strong.
Therefore, the design of the protection device 7 is easy and economical, and the foundation pile 4 can be constructed using the pipe column 1 in the jacket structure 3 as a guide, so the foundation pile can be constructed safely and accurately. can do. In addition, multi-column foundations located in deep water and on soft ground require large cross-sections and a large number of piles in order to suppress horizontal displacement and pile reaction force during earthquakes, but in the case of this invention, each foundation Since the head of the pile is reinforced by the jacket structure 3, the cross section of the pile and the number of piles can be reduced, resulting in easy construction, short construction period, and the ability to construct an economical multi-column foundation. is obtained.

[Brief explanation of drawings]

Fig. 1 is a side view showing an example of a conventional multi-column foundation protection device, Fig. 2 is a plan view thereof, Fig. 3 is a side view showing another example of the conventional multi-column foundation protection device, and Fig. 4 is a side view showing an example of a conventional multi-column foundation protection device. FIG. 5 to 8 show one embodiment of the present invention, in which FIG. 5 is a side view of the multi-column foundation protection device, FIG. 6 is a partially cutaway plan view thereof, and FIG. 7 is a multi-column foundation protection device. FIG. 8 is a partially cutaway side view showing an enlarged part of the column foundation protection device, and FIG. 8 is a partially cutaway plan view showing the relationship between the foundation pile, the jacket structure, and the protection device. In the figure, 1 is a pipe column, 2 is a connecting member, 3 is a steel jacket structure, 4 is a foundation pile, 5 is a supporting vertical member, 6 is a protective beam, 7 is a protective device, 8 is a footing, and 12 is a Mortar, 13 is a steel shim plate, 15 is a steel connecting member, and 16 is a buffer material.

Claims (1)

[Claims] 1 Each pipe column 1 in a steel jacket structure 3 constructed by connecting a large number of pipe columns 1 with a connecting member 2
Each foundation pile 4 of the multi-column foundation is inserted and fixed, and a large number of supporting vertical members 5 are arranged at intervals in the circumferential direction of the jacket structure 3. A multi-column foundation protection device characterized in that a protection device 7 is constructed by attaching a protection beam 6 arranged so as to extend, and each of the vertical members 5 is attached to a jacket structure 3.