JPH0325112A - Device for preventing excessive compression for fender - Google Patents

Abstract

PURPOSE:To lessen impact by constructing the title device of a support member supporting a fixing member attached with a fender in a way of being capable of sliding back and forth and fixing the same to a structure body and a brittle breaking member interposed between the support member and the fixing member. CONSTITUTION:The title device is constructed of a fender 1 made of elastic body such as rubber or the like, a fixing member 5 made of steel plate, a support member 10 made of steel plate and rivets 15 for shear breaking acting as brittle breaking members. When dynamic load exceeding breaking load of the rivets 15 is applied to the device by a floating body such as a ship or the like, the rivets 15 are broken making the fixing member 5 instantaneously slide toward a quaywall 16 for a stroke allowable for the sliding. Furthermore, the fender 1 recovers its displacement quantity from the quantity made by the sliding and absorbs kinetic energy of the ship by deformation made by regenerated reaction force. Thereby buffer operation of the device can be improved.

Description

[Detailed Description of the Invention] The present invention provides a method for connecting a floating body such as a ship and the aforementioned floating body when coming alongside a structure such as a quay, or during coming alongside a structure such as a quay. This relates to fenders that reduce the impact that occurs between them and structures such as quays.

Previously, this type of fender material was published in the Public Utility Model Publication 1983-
There was something like the one disclosed in 184891. As shown in Fig. 8, this device has a stopper made of an elastic body 03 such as solid rubber installed in a sealed space 02 of a fender 01, and a floating body such as a ship is attached to the fender 01. When a large dynamic load is applied, from the point at which the deformation of the fender 01 exceeds its allowable deformation amount, the inner surface of the fender 01 is brought into contact with the elastic body 03 and the elastic body 03 is deformed. The fender absorbs the kinetic energy of the large dynamic load and
1 from being destroyed.

■ ＜"Shiyotoru1" However, with this type of fender, as shown in Figure 8,
When an elastic body installed in a closed space is compressed, the reaction force exerted on floating objects such as ships is the sum of the repulsion force due to deformation exceeding the allowable deformation of the fender OL and the repulsion force due to deformation of the elastic body 03. Not only will the reaction force become excessive, but also the maximum deformation of the elastic body O3 is not large, so even if both reach the limit of deformation, they will still not be able to absorb the kinetic energy of floating objects such as ships. In many cases, there was no such structure, and as a result, floating objects such as the hull of a ship would receive a large reaction force directly from a rigid structure such as a quay, and the load received by floating objects such as the ship's hull would become excessive, which could cause damage to the ship's structure. Further, since the stopper is provided in the sealed space of the buffer member, there are problems such as maintenance is not possible or the amount of deformation of the entire fender is reduced, which reduces the energy absorbed by elastic deformation.

Furthermore, excessive deformation may damage the buffer member, depriving it of its restoring force, and reducing or eliminating its function as a fender.

The present invention relates to an improvement of an overcompression prevention device for fenders that overcomes such difficulties, and includes a fender, a mounting member for removably attaching the fender to the front surface, and a mounting member for removably attaching the fender to the front surface of the fender. A support member located behind the member and slidably supporting the attachment member in the front-rear direction and fixed to the structure, and a brittle fracture member interposed in the support member and the attachment member. It is characterized by the fact that

In addition to the above means, the present invention is characterized in that an elastic member is interposed in the support member and the attachment member in parallel with the brittle fracture member.

Since the present invention is configured as described above, when a dynamic load is applied to the fender from a floating object such as a ship, the fender deforms while generating a reaction force, causing the fender to deform while generating a reaction force. absorbs the kinetic energy of floating objects. This reaction force is transmitted to the floating object such as the ship, and is also transmitted to a structure such as a quay via the attachment member and the support member. As long as this reaction force is within the fracture load of the brittle fracture member, the attachment member does not slide.

However, if the dynamic load received from floating objects such as the ship is large and exceeds the fracture load of the brittle fracture member, the brittle fracture member will be destroyed and the mounting member will instantly slide, allowing sliding. It retreats in the direction of the structure such as the quay by the stroke. Floating objects such as ships cannot move rapidly due to their large inertia, so the fender recovers the amount of deformation due to sliding, and the fender deforms again while generating a reaction force, causing the fender to deform and return to the ship. It becomes possible to absorb the kinetic energy of floating objects such as

Due to the above-mentioned action, when the kinetic energy of the ship or the like is absorbed by the fender, the movement of the floating object on the ship or the like stops, and the deformation of the fender also stops.

Next, due to the reaction force generated by the deformation of the fender, the floating object such as the ship is urged in a direction opposite to the structure such as the quay and gradually moves, and as the fender is The reaction force is lost before the amount of deformation is recovered, and one cycle of the buffering action of the fender device is completed.

Furthermore, as described above, when the brittle fracture member breaks, the mounting member instantly retreats by the allowable sliding stroke toward the structure such as the quay, but at this time, the fender mounting surface of the mounting member The back side collides with the front edge of the support member. If this impact force is predicted to be quite large, by interposing an elastic member in the attachment member and the support member in parallel with the brittle fracture member,
The instantaneous backward movement of the mounting member can be slowed down and the impact force can be alleviated. As described above, when a floating object such as a ship comes alongside a structure such as a quay, the fender device according to the present invention absorbs a dynamic load that exceeds the planned maximum absorption energy of the fender due to some reason to the fender. Even if a load is applied to the fender, it will not be excessively compressed beyond the set deformation amount, nor will it generate an excessive reaction force, and can absorb larger impact energy. Of course, there is no damage to floating bodies such as the ships and structures such as the quays.

In addition, even if the impact force at the time of the fracture of the brittle fracture member is predicted to be quite large, by interposing the elastic member as described above, it is possible to protect not only the fender but also the structure of the ship, etc., the quay, etc. Do not apply excessive shock to objects.

Furthermore, the shape of the brittle fracture member is simple, and the shear fracture load thereof can be easily set. By setting the strength to be greater than the strength of the members, the mounting member and the supporting member are not damaged by the fracture of the brittle fracture member, and are easy to design and have excellent durability.

Furthermore, the brittle fracture members do not break under normal embankment loads, and even if they do break due to excessive loads, the fender and attachment members, and the support members and structures such as quays, can be attached and detached from each other. Since the fender is attached, the fender can be easily detached from a structure such as a quay and landed, and the broken brittle member can be replaced.

Further, it can be applied to any type of fender or cushioning material, and by appropriately selecting the stroke of the sliding portion, the performance of the fender can be set arbitrarily.

Furthermore, it has advantages such as simple structure and low manufacturing cost.

Hereinafter, one embodiment of the present invention illustrated in FIG. 1 will be described.

In Fig. 1, the fender A is installed from the front (hereinafter, the side of floating objects such as ships alongside is referred to as the "front", and the side of the quay side is referred to as the "rear") by the fender 1, the mounting member 5, and the support member 10. It is arranged horizontally and coaxially and fixed to the quay wall 16.

The fender l is made of an elastic material such as rubber, and its main body is shaped like a thick-walled hollow cylinder centered on the center line O-O. In addition to being reinforced to withstand sufficient strength, a smooth berthing buffer surface 2 is formed, and a flange 3 is formed on the rear edge to protrude to the outer periphery, and circular holes for mounting bolts (not shown) are formed in the shape. They are arranged at predetermined intervals along the circumferential direction.

The mounting member 5 is made of a steel plate, and is a disc-shaped member that tightly supports the fender 1 on the front surface and has circular holes arranged in the circumferential direction on the peripheral edge thereof, opposite to the circular holes of the flange portion 3 of the fender 1. a mounting plate 6;
The mounting plate 6 has a cylindrical portion 8 whose front end edge is welded to extend horizontally, and whose rear end edge can be partially fitted into a cylindrical portion 12 of a supporting member 10, which will be described later. It is approximately equal to the outer diameter of the flange portion 3 of the fender l.

The support member 10 is made of a steel plate, and has a circular ring-shaped flange portion 1l in which circular holes for anchor bolts (not shown) buried in the quay wall are disposed in the circumferential direction on the rear surface, and a rear portion along the inner edge of the flange portion 11. It has a cylindrical portion l2 whose end edge is welded and extends horizontally, and into which the rear end edge of the cylindrical portion 8 of the mounting member 5 is fitted into the front end edge.

The inner diameter of the cylindrical portion l2 is approximately equal to the outer diameter of the cylindrical portion 8 of the mounting member 5, and the cylindrical portion 8 is slidable. 8, and when the mounting member 5 retreats and its tip contacts the quay l6, the cylindrical part l2 simultaneously
The mounting plate 6 can come into contact with the tip. The width of the flange portion 1l is sufficient to tighten the anchor bolt.

Circular holes 9 and 13 are disposed on the circumference of the cylindrical portion 8 of the mounting member 5 and the cylindrical portion 12 of the support member 10 on the circumference, and are provided with rivet holes for shear fracture as a brittle fracture member. 5 is inserted and riveted. The length of the insertion portion is such that it can sufficiently withstand the shear breaking load of the rivet seams 5. Further, the cylindrical portion 8 is capable of sliding in the longitudinal direction within the cylindrical portion 12 when the rivet 15 is sheared and broken.

Furthermore, the material used for the rivet 15 is one that has corrosion resistance and is slightly softer than the materials for the mounting member 5 and the support member 10.

The fender l and the mounting member 5 are removably fastened firmly by screwing a nut 7 onto the tip of a bolt 4 inserted through a circular hole, and the support member 10 and the quay wall 16 are connected to each other through a flange portion. A nut 17 is screwed onto the tip of the anchor bolt 4 passing through the circular hole 11, so that the nut 17 is firmly and removably fastened.

The bolt 14 and the nut 17 are made of a corrosion-resistant material or are treated with corrosion-resistant material.

FIG. 2 shows the anti-car displacement dl+ line in the first embodiment, where the vertical axis shows the load of the ship, that is, the reaction force F of the fender l, and the horizontal axis shows the deformation amount Δ of the fender l. is taking. Curve E
shows the elastic properties of the used fender 1 regarding anti-car displacement. Therefore, the area surrounded by the horizontal axis and the curve vAE, that is, the area 0-E Pl-a-O and the area a-Pi-
The sum of P2 b-a indicates the total amount of absorbed energy (T-M) due to deformation of the fender l. According to the experimental results, the planned maximum load of fender L is 100, and rivet 1 is
If the shear failure load of 5 is 1IO, the amount of deformation when the reaction force of fender l reaches 100 is the maximum deformation of 52.
5%, and the amount of deformation of the fender 1 at the point where the shear failure load of the rivet 15 reaches 110 is 55% of the maximum deformation amount.
%Met. Furthermore, due to the shear failure of the rivet 15, the amount of deformation is instantly recovered by the sliding stroke 1 of the mounting member 5, and the total amount of energy absorbed until the deformation continues and the load reaches 110 again is the amount of energy that prevents overcompression. This was 42% more energy than would be absorbed without the device in use.

As is clear from this, the maximum reaction force exerted on the ship, etc. will not exceed 110% of the planned maximum reaction force of the fender l, and the ship, etc. will not be injured by excessive reaction force. In addition, a large amount of absorbed energy can be obtained without causing unreasonable deformation to the fender 1, and even if the rivet 1
Even if the fender 5 undergoes shear failure, there will be no problem in the repeated use of the fender 1. Furthermore, since the mounting member 5 and the support member 10 are made of a material harder than the rivet 15, and the strength of the joint is greater than the shear failure load of the head l5, the rivet 15 is inserted through the shear failure of the rivet 15. Without causing any damage to the areas around the holes 9 and 13, the fender A can be removed from the quay 16, landed, reassembled, and replaced with a sound rivet 15, and other parts can be replaced or repaired. This overcompression prevention device can be reused. Note that when the rivet 15 is sheared and broken, the connection between the attachment member 5 and the support member 10 is released, but at this time, the attachment member 5 slides and is inserted deeply into the support member IO by the stroke l, so that the fender 1 And the mounting member 5 will not fall into the water.

In addition, in this embodiment, as described above, the shear failure load of the rivet 5, which is a brittle fracture member, is set to 110% of the planned maximum reaction force of the fender 1, and the fender at the time of shear failure of the rivet 5 The deformation was set to 55% of its maximum deformation amount, and the sliding stroke l of the mounting member 5 was set to be 42% more than when fender A is not equipped with this overcompression prevention device. The value is not limited to the above, but the rivet l5
The amount of deformation of the fender l under the shear failure load of can be arbitrarily set as long as it is within a range that can be restored and withstand repeated use.

Further, the rivet 15, which is a brittle fracture member, can be replaced with a bolt.

Furthermore, the shape of the fender 1 is not limited to a cylindrical shape, and the cylindrical portion 8 of the attachment member 5 and the cylindrical portion l2 of the support member 10 are also not limited to a cylindrical shape. The attachment member and the support member are slidably joined by the brittle fracture member, and the fender recovers its deformation due to the fracture of the brittle fracture member;
Any material that can deform again and absorb the kinetic energy of floating objects such as ships may be used.

FIG. 3 shows the anti-kerr deformation curve and absorbed energy of a second embodiment in which the hollow cylindrical fender 1 of the first embodiment is replaced with a solid cylindrical fender.

The structure and action are the same and will not be described in detail.

FIG. 4 shows a third embodiment. In this embodiment, a cylindrical member 20 is provided between the mounting member 5 and the support member IO.
The rear edge of the cylindrical portion 8 of the mounting member 5 is inserted into the front edge of the support member 1, and the rear edge of the cylindrical member 20 is inserted into the front edge of the
It is inserted into the cylindrical portion l2 of No. 0, and riveted to the center line circumference of each insertion allowance by passing through rivets 21 and 22, which are brittle breakage members. The shear fracture strength of the rivet 22 is slightly higher than that of the rivet l-21, and the cylindrical member 20
The length of is set to be approximately equal to the length of the cylindrical portion 8 of the attachment member 5 and the length of the cylindrical portion l2 of the support member 10.

First, when the reaction force of the fender 1 exceeds the shear failure load of the rivet I-21, the rivet 21 is sheared and the stroke l
When the mounting member 5 slides backward, the fender 1 recovers its deformation and becomes possible to deform again, and when the fender l deforms again and its reaction force exceeds the shear breaking load of the rivet 2l. , rivet} 21 is sheared and the mounting member 5 is damaged by a stroke l.
slides further aft, and the fender l becomes able to deform again. In this way, in this example, the fender l is 2
Since the deformation is recovered in stages, even if the same fender as in the first embodiment is used, the total amount of absorbed energy increases and the buffering capacity of the fender device is improved. Other functions are the same as those in the first embodiment, and will not be described in detail.

FIG. 5 shows a fourth embodiment. In this embodiment, in addition to the first embodiment, a thick cylindrical elastic body 23
has its front and rear end surfaces in contact with the rear surface of the mounting plate 8 of the mounting member 5 and the front surface of the quay wall 16, and their axes are the same, and a brittle material is formed between the cylindrical portion 8 of the rating member 5 and the cylindrical portion 12 of the support member IO. It is interposed in parallel with the rivet 15, which is a breaking member. As shown in FIG. 6, the elastic properties of the elastic body 23 are such that the maximum amount of deformation is sufficient for the sliding stroke l of the mounting member 5, and when the amount of deformation reaches the stroke l, The reaction force generated is smaller than the reaction force generated when the rivet 15 is sheared and the attachment member 5 slides by a stroke l, and the fender l recovers its deformation by l. Therefore, when the reaction force of the fender 1 exceeds the shear failure load of the rivet 15 and the rivet 15 is sheared, the attachment member 5 slides back without compressing the elastic body 23, but the reaction force of the elastic body 23 As the force increases as shown in FIG. 6, the sliding backward speed decreases, and the cylindrical portion l of the support member 10
The front edge of 2 gently contacts the rear surface of the mounting plate 6 of the mounting member 5. In this way, the elastic body 23 slows down the instantaneous retreat of the mounting member 5 and cushions the impact when the rivet seam 5 breaks due to shearing, and also absorbs energy corresponding to the shaded area in FIG. After the shear failure of the rivet 15, the mounting member 5 can absorb the sliding stroke l while it retreats, thereby improving the buffering capacity of the fender. FIG. 7 shows a fifth embodiment. In this example, the fourth
The elastic body 23 in the embodiment
, and its front end surface is separated from the rear surface of the mounting plate 6 of the mounting member 5 by a distance d. In this embodiment, when the rivet 15 is sheared, the attachment member 5 retreats by d, and the fender 1 instantly recovers from its deformation by d, and thereafter the deformation is removed while compressing the elastic body 23. The dynamic stroke 1 is recovered, and the elastic body 23 is compressed and deformed by f-d.

This embodiment is effective when it is difficult to ensure the maximum amount of deformation of the elastic body 23 by the sliding stroke l.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view showing the structure of the main part of the first embodiment, Fig. 2 shows the anti-Kerr displacement curve in the first embodiment (the area of the shaded area is the amount of absorbed energy), and Fig. 3 FIG. 4 shows the anti-kerr displacement curve (the area of the shaded area is the amount of absorbed energy) in the second embodiment in which the fender in the first embodiment was replaced with a different type (solid type). is a vertical sectional view showing the structure of the main part of the embodiment shown in FIG. 3, FIG. 5 is a longitudinal sectional view showing the structure of the main part of the fourth embodiment, and FIG. Fig. 7 is a longitudinal sectional view showing the structure of the main part of the fifth embodiment, and Fig. 8 is a conventional overcompression prevention method. It is a longitudinal cross-sectional view showing the structure of the main part of the fender with the device. DESCRIPTION OF SYMBOLS 1... Fender material, 2... Buffer side part, 3... Flange part, 4... Bolt, 5... Mounting member, 6...
・Mounting plate, 7... Nut, 8... Cylindrical part, 9...
・Circular hole, 10... Support member, 11... Flange part,
l2... Cylindrical part, 13... Circular hole, 14... Bolt, l6... Quay, l7... Nut, 20... Cylindrical member, 21 22... Rivet, 23... Elastic body.

Claims (2)

[Claims] (1) In a shock absorbing device such as a fender that is attached to a structure such as a quay that accompanies a floating object such as a ship, the fender, the mounting member that removably attaches the fender to the front, and the attachment A support member is located rearward of the member and is fixed to the structure by supporting the attachment member so as to be slidable in the front-rear direction, and a brittle fracture member is interposed between the support member and the attachment member. A fender overcompression prevention device characterized by: (2) An overcompression prevention device for a fender, characterized in that an elastic member is interposed in the support member and the attachment member in parallel with the brittle fracture member.