JPS5942127B2 - Construction method of steel plate cell embankment body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention 1 relates to a method for constructing a steel plate cell embankment body used in harbor construction such as a quay wall, a breakwater, and a deep water revetment.

Large steel plate cells that use a synchronous vibrohammer have many advantages over cells that use conventional flat steel sheet piles, so during installation or driving work, the vibrohammer is used to vibrate the seabed sandy ground. Due to liquefaction, the cell often tilts during driving, making accurate construction difficult.

Therefore, it is desirable to use an exterior jig that restricts the tilt and rotation of the cell.

However, since the cell is huge, efforts must be made to reduce the weight of the jig.

An object of the present invention is to utilize a steel plate cell joint structure for attaching an arc portion in conjunction with an exterior jig.

Another object of the present invention is to use the arc joint structure as a sheath-type slide leader to maintain correct cell spacing and prevent tilting during installation and pouring work of steel plate cells at sea, and to prevent arc The purpose is to prevent rotation of the cell in order to correctly set the mounting position at a predetermined point on its circumference.

Furthermore, in these methods of constructing embankments, it is difficult to install the first cell in the correct position and direction.

Therefore, a further object of the present invention is to provide piles as temporary surveying platforms.
This involves installing a temporary structure, attaching an exterior jig to it, and solving the problem of positioning.

The method of the present invention comprises a step of constructing a temporary pile structure near the planned first cell installation point, a step of detachably attaching an exterior jig having a male leader to the pile structure, and a step of detachably attaching an exterior jig having a male leader to the pile construction. a step of installing the first cell while engaging a female metal fitting for attaching the arc portion of the first cell to a male leader of the tool; and a step of removing the exterior jig from the pile assembly temporary structure and attaching it to the first cell. The second cell is installed while engaging the female metal fitting for attaching the arc portion of the second cell to the male leader of the exterior jig attached to the first cell.

The present invention will be explained in detail below with reference to the drawings.

As shown in FIG. 1, an arc joint structure 3 is attached to the steel plate cell 1 in advance during yard assembly so that the arc section 2 is generally attached at a later stage of construction.

This is a female metal fitting mainly consisting of a sheath-shaped case plate 11 and a horizontal plate-shaped stiffener 12, and its detailed planar shape is shown in FIG.

In the present invention, in order to accurately suspend the next installation cell 1c by using a strong sheath-shaped structure as a female metal fitting including this case plate 11, an existing cell that has already been installed and filled is used as a slide leader. The upper base of the pipe frame 14, which is a steel frame arranged in a triangular shape when viewed from above in plan view and connected by a pin structure, is attached to the top of the steel plate cell with a screw vice 15, and the lower base of the frame 14 is attached to the cell. The cell 1b is formed by a curved plate 16 having a curved surface that matches the outer periphery.
Attach to the outer periphery of the

The apex of the pipe frame 140 has a variable angle structure with the pin hinge 20.

Further, the length of each side can be adjusted by a reverse screw socket 17 inserted between them, that is, a counter-movement rotation mechanism.

FIG. 3 shows the shape of the exterior jig mainly consisting of these pipe frames 14.

7 in the figure is a sliding curved structure material made by processing wood into a curved surface.
It is attached to the H-shaped steel beam 5 via a plate block 6, which is a lightweight steel structure, with bolts and nuts.

This H-shaped steel beam 5 is the main material of the exterior jig and is connected to the pipe frame 14 by a pin hinge 20.

A male leader thick steel plate 9 is attached to the H-shaped steel beam 5 by welding, and a male leader pedestal 8 is attached as a reinforcing material.

The male leader pedestal 8 is a stiffener 1 as a female hardware during work.
It is preferable to use wood as it may occasionally come into contact with 2.

Further, 10 is a male sliding head which is an important sliding member, and is attached to the tip of the male leader thick steel plate 9 with bolts and nuts.

Since this is a consumable item, it is made by processing wood into a curved surface.

As can be seen in FIG. 2, the male sliding head 10 always slides inside the sheath-shaped case plate 11 during the installation and pouring operation.

To engage the above male and female structures, an exterior jig is used to fix the newly suspended cell 1c to the existing cell 1b.
In particular, it descends from above the male sliding head 10.

The opposing rotation movement mechanism by the reverse screw socket 17 is used to adjust the side length of the pipe frame 140, as shown in FIG. A locking groove 32 is provided in the axial direction in a part of the thread formed in the pipe frame 14 so that it can be fixed with a locking bolt 19, and a reverse threaded socket 17 is provided in this groove 32.
The locking bolt 19 is engaged through the socket to prevent the socket from rotating due to vibration.

Generally, the hoist ship 30 that is engaged in transporting, installing, and pouring steel plate cells is required to have a reach that corresponds to the diameter of the cell, and a large hoist ship must be selected.

In FIG. 5, the upper end of the steel plate cell 1 is clamped by a hydraulic chuck 25, and a synchronous vibrohammer 29 is positioned directly above it.

Furthermore, above it is a suspension support 23 made of steel girders.
They are connected by extending the same number of branches as the number of vibrohammers used, and are usually hoisted by a hook on the host block 21 of a hoist ship using a wire rope 31 with a supporting stand via a hanging hardware such as an eyepiece.

Therefore, it is common knowledge that wire robes with supporting stands are of the same length, but this is different in the case of the present invention.

In the present invention, the lifting point of the organizer block 21 is intentionally set off the center of the circular steel plate cell, and the weight of the cell is transferred to the support block 21 and an auxiliary hoist connected to one of the lifting supports 23 by a wire rope and an eyepiece. The burden is placed on both the block 22 and the block 22.

The load sharing ratio is set according to the actual situation at the site, and the length of each attached wire rope is calculated and adjusted accordingly.

By suspending the cell at two points in this manner, rotation of the lifted steel plate cell can be suppressed and smooth work can be carried out throughout almost the entire process.

Another work problem is that the first
It is difficult to determine the location of the cell 1a on the sea, and a solution is needed.

As is common sense in port construction, the installation of cell groups begins at the corners.

That is, in FIG. 6, the first cell 1a is installed first, but the other second cell 1b, third cell 1c
Accurate installation work is extremely difficult compared to

In the method of the present invention, a pipe frame 14 and a male slide head 9 are pre-assembled into a pile-assembled temporary structure that also serves as a surveying platform, which is made up of an H-shaped steel pile 26, a shaped steel temporary structure member 27, and a wooden floor plate 28, as shown in FIG. The main parts of the exterior jig consisting of , sliding wood 7, etc. are attached and used to accurately suspend and cast the first cell.

Next, the method for constructing the steel plate cell embankment body of the present invention will be described in accordance with the order of construction.

First, a steel plate cell welding assembly yard is usually installed in a sea-facing premises within the Taiyo Shipyard, and the welding assembly work is carried out while attaching several stages of inner ring frames 4 as interior jigs.

Since the thickness of the steel plate used in the steel plate cell is extremely thin compared to its diameter, without the inner ring frame 4, it would be impossible to maintain its perfect circle throughout the entire process of assembly, transportation, installation, pouring, etc. .

The exterior jig used in the method of the present invention is effective only when combined with this interior jig.

Sea transportation of steel plate cells is usually carried out using large barges.

At the installation site offshore, necessary ground improvement work will be carried out in parallel, and survey stands made of steel such as H-shaped steel will be installed as temporary structures with piles at key points.

Normally, the break is made at point B on the extension of the cell center line shown in FIG. 6, or at point 0 on the extension of the front surface line, but in the case of the present invention, it is set at point A, which is neither of these points.

Point A can be easily converted from the viewpoint of surveying technology by shifting the coordinate axes as the position of the surveying platform.

When installing the exterior jig, the steel frame of the pipe frame 14 is disassembled at the position of the reverse threaded socket 17, and a new steel pipe for field fitting is screwed into the socket.

The exact position of the male leader sliding portion is adjusted using the reverse screw socket 17 based on the results of another precision survey.

As shown in FIG. 5, the steel plate cell 1 hoisted by a hoist ship is fitted with a case plate 11, an arc joint structure consisting of a stiffener 12, and a female metal fitting, with a two-part shaped cap 24 attached to its lower end. protected.

By careful shifting of the hoist using the anchor wire, the pointed cap 24 reaches directly above the male leader, and thereafter the steel plate cell is suspended while its female hardware and male leader slide.

In other words, loosen the hoisting wire of the hoist and make sure that the slide guide is working effectively and lower the hoist at low speed, but in reality, the lowering level of the sovereign block and the auxiliary hoisting block do not necessarily have to be the same. do not.

For example, unexpected tilting may occur due to factors such as wind pressure, and adjustment is required.

The two-point hanging method of the present invention can effectively deal with this problem.

If the tip of the cell slightly penetrates the sea floor and the descent stops,
Next, the synchronous vibrohammer 29 is activated to drive the steel plate cells to a predetermined depth.

With the above steps, the installation and pouring process of the first cell 1a has been completed.

Next, the hydraulic chuck 25 is opened, the lifting support is hoisted up, the hoist is removed, the inner ring frame 4 is removed, and the filling sand 13 is immediately thrown into the embankment.

In addition, the temporary structure made of piles shown in Figure 5 will be promptly removed.
After recovering the pipe frame 14 as an exterior jig, the end pipe frame including a hanger vise 15 and a curved plate 16 as regular parts is attached to the reverse threaded socket as a regular exterior jig as shown in Fig. 3. Return.

The cell installation and pouring work for the second cell 1b and subsequent cells can be carried out more easily by substantially the same procedure by sliding the exterior jig.

According to experimental work that did not use external jigs and did not impose any slope restrictions, the penetration speed of steel plate cells into the ground using a synchronous vibrohammer was surprisingly fast, and when the hanging wire was loosened sufficiently, the cells immediately sloped. It is known that if the hanging wire is tightened, it will easily return to its upright position.
The angle of inclination at this time is as much as 30 degrees.

This is because the vibrations of the vibrohammer liquefy the seabed sandy ground, and while penetration is easy, the cell is extremely prone to tilting, and providing a guide jig is extremely advantageous in construction. has become clear.

It has also been known through experiments that no significant external force acts on this exterior jig.

Therefore, the pipe frame, which has a planar shape like two triangles combined as shown in FIG. 1, can be made lighter and made into a single triangle frame.

Further, the hanger vise 15 may be replaced with a hydraulic chuck, and the lower curved plate 16 may be connected with a pin to an eyepiece that is in contact with the cell.

Various modifications are possible depending on the application.

In any case, according to the method of the present invention, even if the cell is a huge steel plate exceeding 30 m in diameter, the prescribed cell spacing can be maintained accurately and the arc installation position can be maintained in the circumferential direction of the cell. A construction method that prevents rotation and meets the demands of rapid construction can be accurately implemented using the sheath type steel structure as an arc partial cell joint structure.

[Brief explanation of the drawing]

Figure 1 is a plan view showing how the exterior jig of the present invention is installed;
The figure is a plan view showing details of the sliding part of the exterior jig of the present invention, Figure 3 is a perspective view illustrating the overall structure of the pipe frame of the exterior jig of the present invention, and Figure 4 is a side length adjustment device for the pipe frame. FIG. 5 is a partially cutaway perspective view showing a method for lifting two lifting supports using a starter boat, FIG. 6 is a plan view showing a method for installing the first cell, and FIG. 7 is a perspective view of the first cell. FIG. 2 is a perspective view of a pile-set structure used during installation work. DESCRIPTION OF SYMBOLS 1... Steel plate cell, 2... Arc part, 3... Arc part joint structure, 4... Insertion ring frame, 5... H-shaped steel beam 6... Plate block, 7...・Sliding curved surface structural material, 8... Male leader single pedestal, 9... Male leader thick steel plate, 10... Male sliding head, 11... Case plate, 12... Stiffener, 13...・Filled sand, 14...
・Pipe frame, 15...Bunker vice, 16・
...Curved surface plate, 17... Reverse screw socket, 18.
...Band Tool, 19...Rocking Bold, 2
0...Pin hinge, 21...Organizer block, 22.
... Auxiliary winding block, 23 ... Lifting support, 24 ...
Pointed cap, 25...Hydraulic chuck, 26...H-shaped steel pile,
27... Temporary steel structure member, 28... Wooden floor board, 2
9... Synchronous vibrohammer, 30... Hoist ship,
31... Wire rope with support stand, 32... Locking groove, ]5 Completed

Claims (1)

[Claims] 1. A step of constructing a temporary pile structure near the planned installation point of the first cell, a step of detachably attaching an exterior jig having a male leader to the temporary structure, and a step of installing the first cell while engaging the male leader of the jig with a female metal fitting for attaching the arc portion of the first cell; and a step of removing the exterior jig from the pile-assembly temporary structure and attaching it to the first cell. and a step of installing the second cell while engaging the female metal fitting for attaching the arc portion of the second cell to the male leader of the exterior jig attached to the first cell. construction method. 2. The male leader consists of a male leader thick steel plate and a male sliding head formed on the end face of the male leader thick steel plate, and the exterior jig includes a telescopic pipe frame connected in a triangular shape, and an upper end of the cell. The construction method according to claim 1, comprising a banger vice that can be engaged with the cell and a curved plate that matches the outer peripheral surface of the cell.