Reinforcement structure and method for cylindrical bodies installed on the seabed.

Abstract

To provide a reinforcement structure of underwater installation cylindrical body capable of being easily constructed and suitably reinforcing a cylindrical body such as a steel pipe pile for supporting mono-pile foundations, piers, and the like, and a reinforcement method.SOLUTION: A reinforcement structure of an underwater installation cylindrical body 3 includes a reinforcement cylindrical body 7 that is placed outside the underwater installation cylindrical body 3. The reinforcement cylindrical body 7 includes: an inner tube 8 placed along the outer periphery of the underwater installation cylindrical body 3; an outer tube 9 placed outside the inner tube; and an upper lid 11 that closes the upper surface of a compartment 10 formed between the inner tube 8 and the outer tube 9. The reinforcement cylindrical body 7 is designed to penetrate underwater ground 1 by depressurizing the compartment 11.SELECTED DRAWING: Figure 2

Claims

1. A reinforcing structure for a cylindrical body installed on the seabed, which is erected on the seabed while being penetrated into the seabed ground, The aforementioned cylindrical body for installation on the seabed is equipped with a reinforcing cylindrical body positioned on the outside, The reinforcing cylindrical body comprises an inner tube arranged along the outer circumference of the cylindrical body for installation on the seabed, an outer tube arranged outside the inner tube, and a top cover that closes the upper surface of the partition formed between the inner tube and the outer tube, and is provided at the top with a stiffness change suppressing member having lower bending stiffness than the reinforcing cylindrical body. A reinforcing structure for a cylindrical body installed on the seabed, characterized in that it is designed to penetrate the seabed ground by reducing the pressure inside the compartment.

2. The reinforcing cylindrical body for installation on the seabed according to claim 1, wherein the reinforcing cylindrical body comprises a plurality of reinforcing ribs that connect the inner tube and the outer tube at intervals in the circumferential direction.

3. The reinforcing rib is formed in the shape of a plate separating the compartments in the circumferential direction and has an insertion hole that penetrates in the thickness direction of the plate, as described in claim 2.

4. The reinforcing cylindrical body for installation on the seabed according to any one of claims 1 to 3, wherein the reinforcing cylindrical body is composed of a plurality of divided cylindrical bodies that are divided in a longitudinal section.

5. The reinforcing cylindrical body for installation on the seabed according to any one of claims 1 to 4, wherein the reinforcing cylindrical body has a drain pipe attached to it that penetrates the top cover and communicates with the partition.

6. A reinforcing structure for a cylindrical body for installation on the seabed according to any one of claims 1 to 5, wherein a filler material is filled in the gap between the inner tube and the outer surface of the cylindrical body for installation on the seabed.

7. A method for reinforcing a cylindrical body for installation on the seabed, which is erected on the seabed while being penetrated into the seabed ground, A reinforcing cylindrical body is used, comprising an inner tube arranged along the outer circumference of the cylindrical body for installation on the seabed, an outer tube arranged outside the inner tube, and a top cover that closes the upper surface of the partition formed between the inner tube and the outer tube, and a stiffness change suppressing member having lower bending stiffness than the reinforcing cylindrical body is provided on the upper part of the reinforcing cylindrical body. After placing the reinforcing cylindrical body on the outside of the cylindrical body for installation on the seabed and resting its lower end on the seabed ground, A method for reinforcing a cylindrical body for installation on the seabed, characterized by reducing the pressure inside the partitioned chamber and penetrating the reinforcing cylindrical body into the seabed ground.

8. The method for reinforcing a cylindrical body for installation on the seabed according to claim 7, wherein the reinforcing cylindrical body is divided into a plurality of divided cylindrical bodies by dividing it in a longitudinal section, and each divided cylindrical body is joined together on the seabed ground along the outer surface of the cylindrical body for installation on the seabed.

9. A method for reinforcing a cylindrical body for installation on the seabed according to claim 7 or 8, wherein after the reinforcing cylindrical body is driven into the seabed ground, the soil between the inner pipe and the cylindrical body for installation on the seabed is removed to form a gap, and a filler material is filled into the gap.

10. A method for reinforcing a cylindrical body for installation on the seabed according to any one of claims 7 to 9, wherein the shear force and bending moment acting on the cylindrical body for installation on the seabed are analyzed, and the penetration length of the reinforcing cylindrical body is set based on the analysis results obtained for each depth.

11. A method for reinforcing a cylindrical body for installation on the seabed according to any one of claims 7 to 10, wherein a scour prevention member is attached to the upper outer circumference of the reinforcing cylindrical body before it is driven into the seabed ground.

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