JPH0782731A - Construction method of horizontal drainage member in seabed and device - Google Patents

Abstract

PURPOSE:To carry out work very efficiently to reduce a construction period by executing simultaneously the construction of horizontal drainage members and the imbedding of vertical drainage members in one stage of work concurrently and to enable the supply and receiving of water from the vertical drainage members to the horizontal drainage members. CONSTITUTION:Construction members 7 having belt-shaped horizontal drainage members 8 are horizontally arranged on a construction surface, the horizontally arranged construction members 7 are made to pass through vertically to imbed vertical drainage members 2 vertically in the ground under the construction surface, and a device 16 preventing the warp of the construction members 7 is applied to the vertical drainage members 2 facing on the construction members 7. The horizontal drainage members 8 of the construction members 7 are continuously constructed on the construction surface while repeating a series of works mentioned above. Accordingly, work can be very efficiently carried out to shorten greatly a construction period by executing the construction work of the horizontal drainage members and the embedded work of the vertical drainage members in the ground simultaneously as a series of works in one stage of work.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground improvement work using a vertical drainage member such as a plastic board or sand sand pile to remove water from the ground at the bottom of the water for land reclamation. The present invention relates to a construction method and device for laying a horizontal drainage member on the ground.

[0002]

2. Description of the Related Art As a conventional ground improvement work for a water bottom, for example, as shown in FIG. 19, a soft ground 30 containing a large amount of water is used.
Form a sand mat 17 laid on the top with a height of about 1 to 1.5 m, that is, with good quality, that is, having rough eyes and excellent water permeability, and then penetrate the sand mat 17 to make a plastic board, sand pile, etc. The vertical drain member 42 is vertically embedded in the soft ground 30 to be embedded therein.

Embankment 4 is placed on such a sand mat 17.
When a heavy load is applied to the sand mat 17 by applying 4 or the like, the water contained in the soft ground 30 passes vertically through the gap formed in the vertical drain member 42 as shown by the arrow in the figure. When the sand mat 17 rises and reaches the sand mat 17, the sand mat 17 moves horizontally through the gaps of the rough mesh and is drained from the side surface of the sand mat 17 into the surrounding water.

However, the high quality sand used for the sand mat 17 has become difficult to obtain in recent years in order to prevent natural destruction and environmental problems, and even if it is available, it becomes very expensive. There is a problem that it is not profitable.

In order to solve such a problem, Japanese Patent Application Laid-Open Nos. 62-233322 and 62-233323 disclose "a method for continuously laying a plate drain on the water bottom".
There is "a water drain continuous laying device for plate drains".

In the "water bottom continuous laying method for plate drains" of the above-mentioned publication, plate drains are continuously laid on the bottom of the water from a laying ship that moves straight, and weight members are placed on the plate drains. It is characterized in that the plate-like drain is stably pressed against the bottom of the water by dropping the above. A gantry set on the laying ship, a winding drum rotatably mounted on the gantry, a casing for guiding and guiding a plate-shaped drain drawn from the winding drum to the water bottom, and a casing for the casing. And a chute for dropping a weight member such as crushed stone provided along the rear portion.

In these conventional examples, a plate-shaped drain produced from a factory or the like is used as a substitute for the sand mat 17 so as to solve the current problem that it is difficult to obtain good quality sand in ground improvement work. To do.

[0008]

However, in these conventional "plate drain laying method" and "plate drain laying apparatus", after the vertical drain member is driven into the ground and buried, Since it is necessary to separately perform the two-step work such as laying a drain on the bottom of the water, there is a problem that the period required for the whole ground improvement work becomes long.

Further, in this conventional example, unless the plate-shaped drain is pressed down on the bottom of the water, the plate-shaped drain is curled up and cannot be brought into contact with the vertical drain member previously buried in the ground. The method of dropping weight such as crushed stones on the drain is adopted. However,
Only by dropping such weights, it is not possible to effectively prevent the plate-shaped drain from being turned up. Therefore, there is a problem that the drainage action of water by the drainage member is not sufficiently performed.

Further, since there is a large time gap between the burying work of the vertical drainage member and the laying work of the plate-like drain, sludge and sand float in the water during the construction, so that the vertical drainage member and the plate-like drainage Sludge and sand are easily caught between the drain and the drain, so that the water cannot be reliably transferred from the vertical drainage member to the horizontal drainage member, resulting in the same problem as described above.

Therefore, the present invention makes the construction extremely efficient and shortens the construction period by laying the horizontal drainage member and embedding the vertical drainage member in parallel in one step at the same time, and also flips up the horizontal drainage member. Can be effectively prevented,
By preventing sludge and sand from getting caught between the vertical drainage member and the plate drain, water can be reliably delivered from the vertical drainage member to the horizontal drainage member, and the drainage action can be sufficiently improved. An object of the present invention is to provide a method and an apparatus for laying a horizontal drainage member.

[0012]

In order to solve the above-mentioned problems, a method of laying a horizontal drainage member on a water floor according to the present invention is a method of laying a laying member having a belt-shaped horizontal drainage member horizontally on a laying surface, and A means for preventing the curving of the laying member in the vertical drainage member facing the laying member by vertically piercing the laying member arranged horizontally and vertically burying the vertical drainage member in the laying surface groundwork. It is characterized in that the laying member is continuously laid on the laying surface while repeating these series of operations, and the laying device for the horizontal drainage member at the water bottom according to the present invention is a strip-shaped member. Laying member holding means for holding the laying member in which the horizontal drainage member and the net-shaped ground reinforcing member are integrated so that the laying member can be drawn out, and the laying member for laying the laying member horizontally on the laying surface. Laying member drawing means that draws out from the holding means, vertical drainage member embedding means that vertically penetrates the laying member horizontally arranged on the laying surface to vertically bury the vertical drainage member in the ground of the laying surface, and the laying It is characterized in that the vertical drainage member facing the member is provided with a curl preventing means for preventing the laying member from curling.

[0013]

According to the method and apparatus for laying a horizontal drainage member on the water bottom having such a structure, the laying work of the laying member having the horizontal drainage member and the burying work of the vertical drainage member in the ground are performed in one step. By repeating the work in parallel while performing the work in parallel, it is possible to perform two work in the same process at a time with two conventional processes at the same time, thus making the work extremely efficient and significantly shortening the construction period. It will be possible.

Further, the vertical drainage member is vertically embedded in the laying surface ground by penetrating the laying member in the vertical direction, and the vertical drainage member facing the laying member thereafter is provided with a means for preventing the laying member from turning up. The horizontal drainage member can be effectively prevented from being turned over as compared with the weight such as crushed stone in the conventional example, so that the water can be reliably delivered from the vertical drainage member to the horizontal drainage member, and the drainage action is sufficiently improved. be able to.

Further, since there is almost no time interval between the laying work of the laying member and the burying work of the vertical drainage member in the ground, sludge or sand is not caught between the horizontal drainage member and the vertical drainage member. Since there is no direct contact between the two,
After all, the water can be reliably delivered from the vertical drainage member to the horizontal drainage member, and the drainage action can be sufficiently improved.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 13 are views showing an embodiment of a method and apparatus for laying a horizontal drainage member on a water bottom according to the present invention.

FIG. 1 is a view showing a special ship as a laying device for a horizontal drainage member on a water bottom according to the present invention. In the figure, reference numeral 1 is a hull of a dedicated ship, and this hull 1 has a substantially rectangular outer shape when viewed from above, and a substantially rectangular center well 3 penetrating in the vertical direction is formed inside thereof. ing.

A laying frame body 13 is provided below the hull 1, and the laying frame body 13 is provided so as to be vertically movable with respect to the hull 1 through a guide post 25 using a steel pipe or the like.
It is possible to descend toward the bottom of the water or ascend toward the hull 1. By using such a laying frame body 13 for laying work, it becomes possible to lay the horizontal drainage member 8 at a predetermined position on the laying surface accurately.

The hull 1 is provided with a setting device 27 (vertical drainage member embedding means) for driving the vertical drain member 2 (vertical drainage member) into the soft ground 30 at the bottom of the water. The placing device 27 has a turret structure 4, and the turret structure 4
Is a rail member 28 provided along both sides of the hull 1.
It is supported above and can run in the front-back direction of the hull 1 along the upper surface of the rail member 28.

The driving device 27 has a mandrel 5 which encloses the vertical drain member 2 and an underwater guide 6 for guiding the mandrel 5. The underwater guide 6 is movable in the vertical direction relative to the turret structure 4, and the mandrel 5 is movable in the vertical direction relative to the underwater guide 6, and the underwater guide 6 and the mandrel 5 are Both pierce the center well 3 and move up and down.

The mandrel 5 protects the vertical drain member 2 contained therein and also has a function as a casing for driving the vertical drain member 2 into the ground. That is, when driving the vertical drain member 2, the mandrel 5 is driven into the ground, and when the mandrel 5 is pulled out from the ground thereafter, the vertical drain member 2 remains in the ground as described later, and only the mandrel 5 is pulled out to the ground. Be done.

When the mandrel 5 is pulled out to the ground, the horizontal drain member 8 is left in the ground so that the vertical drain member 2 faces the horizontal drain member 8 for a predetermined length.
The vertical drain member 2 is cut at a predetermined length above the base, and this cutting is performed by a rotary cutter (not shown) built in the tip of the mandrel 5. By the way, before performing such cutting, the fixing member attaching device 16 (turning prevention means) provided at the lower end portion of the underwater guide 6 is used as shown in FIG.
The pin type fixing member 18 is attached to the vertical drain member 2 facing the horizontal drainage member 8 as shown in FIG.

As the vertical drain member 2, a plastic board having irregularities on both front and back surfaces is used. For example, "Geo drain" (trade name) sold by Marubeni Construction Machinery Sales Co., Ltd. is used. The vertical drain member 2 has a long strip-like shape with a cross-sectional shape as shown in FIGS. 3 and 4, and has a structure in which a filter 2b wraps around a core body 2a having unevenness on both front and back surfaces. Has become. The material of the core 2a is polyolefin resin, the filter 2
Cellulose, polyester-based synthetic fiber non-woven fabric or the like is used as the material of b, but other materials may be used.

Further, the hull 1 is provided with a plurality of drums 9 for rolling a band-shaped horizontal drainage member 8 and continuously holding the drainage member 8, and a net-shaped ground reinforcing member 10 for rolling. , A plurality of drums 11 are provided for continuously holding the drums 11 so that they can be pulled out. Further, in the vicinity of the drums 9 and 11, a plurality of horizontal drainage members 8 and a plurality of ground reinforcement members 10 that have been pulled out are integrally sewn to form a wide laying member 7. Is provided. The drums 9 and 11 and the sewing device 12 constitute a laying member holding means.

As the horizontal drainage member 8, for example, "Public drain" (trade name) manufactured by Asahi Engineering Co., Ltd. is used. As shown in FIG. 5, the horizontal drainage member 8 has a structure in which a filter 8b wraps both sides of a core body 8a having irregularities on the front and back sides. Core body 8
Although hard vinyl chloride is used as the material of a and polyester long-fiber nonwoven fabric is used as the material of the filter 8b, other materials may be used.

As the ground reinforcing member 10, for example, "Netron sheet" (trade name) manufactured by Mitsui Petrochemical Co., Ltd.,
"Yukaron Net" (trade name) manufactured by Mitsubishi Petrochemical Co., Ltd.,
Similarly, “Tensor” (trade name) manufactured by Mitsubishi Petrochemical Co., Ltd. and the like are used, and each of them has a net shape but no knot. High density polyethylene is mainly used for civil engineering as the material of "Netron", polyethylene is used as material of "Yukaron net", and high density polyethylene and polypropylene are used as material of "Tensor". Is used.

Referring again to FIG. 1, the laying frame 13 is provided with a drawer device 14 (laying member drawing means).
This drawer device 14 holds the tip of the laying member 7 in which the horizontal drainage member 8 and the ground reinforcing member 10 are sewn and integrated by the sewing device 12 and moves from the right side to the left side of the laying frame body 13 in FIG. By moving, the laying member 7 is arranged horizontally on the laying surface of the soft ground 30 at the bottom of the water.

A cutting device 15 such as an electric saw is provided on the front side (right side in the figure) of the laying frame body 13 above the laying member 7 which is pulled out by the drawer device 14 and is arranged in the horizontal direction. The cutting device 15 can cut the laying member 7 when the laying member 7 is completely laid.

Next, the operation of the hull 1 according to the above embodiment will be described. First, as shown in FIG. 6, the hull 1 is towed to the laying site in a state where the laying frame body 13 is raised to the maximum and stored in the hull of the hull 1. Then, the position is fixed to the laying site by the anchor via the chain 32. At this time, a plurality of horizontal drainage members 8 and ground reinforcement members 10 are respectively drawn from the drums 9 and 11 and integrally sewn by a sewing device 12 to form a laying member 7, and the tip end of the laying member 7 is a pulling device 14. Being gripped by.

Next, as shown in FIG. 7, the guide post 25
The laying member 13 in which the horizontal drainage member 8 and the ground reinforcing member 10 are integrally sewn together with the laying frame body 13 being lowered to the soft ground 30 on the bottom of the water by the drawing device 14 It is pulled to the left end of the center and placed horizontally on the bottom of the soft ground 30 to be laid.

Next, as shown in FIG. 8, the underwater guide 6 descends and the fixing member attaching device 16 at the lower end portion thereof is installed in the laying frame 1.
3, the mandrel 5 descends under the guidance of such an underwater guide 6. Therefore, when the vertical drain member 2 is driven into the ground by the mandrel 5, the laying member 7
Prevent them from being pulled into the ground or turned over together. The mandrel 5 penetrates in the vertical direction through the ground reinforcing member 10 that constitutes one of the laying members 7, and is driven into the laying surface foundation 30 for a certain length. At this time, the vertical drain member 2 housed in the mandrel 5 is driven into the ground together with the mandrel 5 while being protected by the mandrel 5.

An anchor plate 34 as shown in FIG. 9 is attached to the tip of the vertical drain member 2 in the mandrel 5, and when the mandrel 5 is driven into the ground, both ends of the anchor plate 34 are shown as shown in FIG. The part is bent along the tip of the mandrel 5, and is smoothly driven into the ground 30 together with the mandrel 5.

Then, as shown in FIG. 10, when the underwater guide 6 is left as it is and only the mandrel 5 is raised, as shown in FIG. 11, the anchor plate 34 attached to the tip portion of the vertical drain member 2 is attached. The ends of the anchor plate 34 are expanded because of resistance in the ground.
Are left in the ground together with the vertical drain member 2. In this way, the first vertical drain members 2 penetrate the laying member 7 and complete the driving into the ground 30.

Next, the vertical drain member 2 driven into the ground is cut by a rotary cutter built in the tip of the mandrel 5 leaving a predetermined length above the laying member 7, but before that. 2 by the fixing member attaching device 16
As shown in FIG. 3, a pin type fixing member 18 is attached to the middle portion of the vertical drain member 2 so that the laying member 7 will not be turned over later.

Since the vertical drain member 2 of a predetermined length that has been cut and left on the laying member 7 falls on the horizontal drain member 8 and overlaps them so as to contact each other, it is sucked up from the ground by the vertical drain member 2. The water is directly transferred to the horizontal drainage member 8 and drained to the outside by the horizontal drainage member 8.

After cutting the vertical drain member 2 from the laying member 7 of the vertical drain member 2 so as to leave a predetermined length facing the laying member 7, the mandrel 5 and the underwater guide 6 are lifted above the water surface and the inside of the mandrel 5 is removed. The anchor plate 34 is attached to the tip of the vertical drain member 2 again, the turret structure 4 of the driving device 27 is slightly moved to the right side in FIG. 10, and the same operation as described in FIGS. 8 to 10 is repeated. The vertical drain member 2 is driven for the second time. When such driving of the vertical drain member 2 is repeated a plurality of times, as shown in FIG. 12, a large number of vertical drain members 2 are driven into the ground.

In this way, as shown in FIG. 12, when the turret structure 4 comes to the rightmost side and the planned number of vertical drain members 2 have been driven in, the mandrel 5 and the underwater guide 6 are moved as shown in FIG. And the laying frame 13
Is lifted by a certain distance to release the grasping of the laying member 7 by the drawer device 14, and then the hull 1 is moved by a predetermined distance without cutting the laying member 7. At this time, the horizontal drainage member 8 and the ground reinforcement member 10 are continuously drawn out by the movement of the hull 1, and are sewn by the sewing device 12 to be the laying member 7, which is laid on the bottom of the laying frame body 13. .

After the hull 1 is moved, its position is fixed again by the anchor, and the laying frame body 13 is lowered to the soft ground 30 at the bottom of the water through the guide post 25, whereby the laying member 7 is softened as shown in FIG. It is arranged horizontally on the ground 30. After that, the same operation as described above with reference to FIGS. 8 to 12 is repeated. By repeating such a series of operations, the laying member 7 can be continuously laid in the laying construction area, and when all the construction in the planned area is completed, the laying member 7 is cut by the cutting device 15 to lay the laying frame. The body 13 is raised and moved to another laying construction area.

In the above embodiment, the case where the fixing member attaching device 16 attaches the pin type fixing member 18 to the vertical drain member 2 as the turning-over preventing means has been described, but as shown in FIG. 14, the vertical drain member 2 is clipped. The die fixing member 19 is locked, the vertical drain member 2 is locked with the ring fixing member 20 as shown in FIG. 15, and the vertical drain member 2 is engaged with the donut-shaped fixing member 21 as shown in FIG. 17, the vertical drain members 2 are joined to each other using a joining member 22 as shown in FIG. 17, or the plurality of vertical drain members 2 are made of the same material as the vertical drain member 2 as shown in FIG. You may make it join by the member 23 for.

[0040]

As described above, according to the present invention, it is possible to solve the conventional environmental problems such as natural destruction due to natural sand collection and water pollution during sand mat construction, as well as the horizontal drainage member. By repeating the laying work and the burying work of the vertical drainage member as a series of work, the conventional two-step work can be performed simultaneously in one process, which makes the work extremely efficient. It is possible to significantly shorten the construction period.

Further, the laying member having the horizontal drainage member is vertically penetrated to vertically bury the vertical drainage member in the foundation of the laying surface, and then the laying member is prevented from being turned upside down on the laying member. Since the means is provided, it is possible to effectively prevent the horizontal drainage member from being turned over as compared with the weight such as the crushed stone in the above-mentioned conventional example. Therefore, it is possible to reliably deliver the water from the vertical drainage member to the horizontal drainage member, and to perform the drainage action. Can be sufficiently improved.

Since there is almost no time interval between the laying work of the laying member and the burying work of the vertical drainage member in the ground, no sludge or sand is caught between the horizontal drainage member and the vertical drainage member. Since there is no direct contact between the two,
After all, the water can be reliably delivered from the vertical drainage member to the horizontal drainage member, and the drainage action can be sufficiently improved.

Further, according to the present invention, not only the horizontal drainage member (laying member) can be surely prevented from being turned up by the turning-up preventing means, but also the vertical drainage member is cut and remains on the installation member for a predetermined length. Since the drain member overlaps the horizontal drainage member and both are in direct contact with each other, the water drained from the ground by the vertical drainage member can flow into the horizontal drainage member more reliably, and the delivery of water is performed perfectly. Be seen.

Further, in the above-mentioned embodiment, when landfilling is carried out while using the laying site as a waste disposal site, the sand for sand mat, which has been used in large quantities in the past, is not necessary, and thus it is conventionally used. A space is available for the volume of sand, which can increase the amount of waste disposal more than before.

Also, the vertical drain member 2 and the horizontal drain member 8
Since the factory products are used, stable supply is possible, quality can be kept constant, and reliability of the drainage effect can be improved.

Further, since the laying frame body 13 is used such that the laying frame body 13 is lowered to the water bottom and the horizontal drainage member 8 is horizontally arranged on the water bottom, the horizontal drainage member 8 is laid exactly at a predetermined position. It has become possible. In addition, the lower end of the underwater guide 6 is lowered onto the laying member 7,
Since the mandrel 5 drives the vertical drain member 2 into the ground by being guided to the ground, it is possible to prevent the laying member 7 from being pulled into the ground or curling up during the driving.

Further, as described in the above-mentioned conventional publication, by placing a weight bag or the like filled with sand or aggregate in addition to sand or gravel on the horizontal drain member at the bottom of the water. Compared with the one that prevents the turn-up, in the dedicated ship of the above-mentioned embodiment, since such heavy objects as sand, gravel, weight bag, etc. are unnecessary, there is a space for accommodating such heavy objects and onboard the ship. Therefore, it is possible to prevent the work of making a weight bag and the like from being unnecessary, prevent the special ship from being unnecessarily increased in size, and save the time and trouble in handling the heavy objects, thereby improving the efficiency and automation of the work.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing the structure and operation of a dedicated ship according to an embodiment of a method and apparatus for laying a horizontal drainage member on a water bottom according to the present invention.

FIG. 2 is a partially enlarged perspective view showing a state in which a pin-type fixing member 18 is attached to a portion of the vertical drain member 2 which is located above the laying member 7 and a pile-up preventing unit is provided.

FIG. 3 is a cross-sectional view when the vertical drain member 2 is cut in the width direction.

4 is an enlarged view of an IV portion in a circle of the vertical drain member 2 in FIG.

5 is a perspective view showing a shape of a core body 8a by flipping a part of a filter 8b of the horizontal drainage member 8. FIG.

FIG. 6 is a side view for explaining the operation of the exclusive ship shown in FIG.

FIG. 7 is a side view for explaining the operation of the special ship.

FIG. 8 is a side view for explaining the operation of the special ship.

9 is an anchor plate 34 attached to the tip of the vertical drain member 2 when the mandrel 5 is driven in. FIG.
FIG.

FIG. 10 is a side view for explaining the operation of the special ship.

FIG. 11: Anchor plate 3 attached to the tip of the vertical drain member 2 when the mandrel 5 is pulled out
It is sectional drawing which shows 4.

FIG. 12 is a side view for explaining the operation of the special ship.

FIG. 13 is a side view for explaining the operation of the special ship.

FIG. 14 is a partially enlarged perspective view showing another embodiment provided with a turning-up prevention means.

FIG. 15 is a partially enlarged perspective view showing another embodiment provided with a turning-up preventing means.

FIG. 16 is a partially enlarged perspective view showing another embodiment provided with a turning-up prevention means.

FIG. 17 is a partially enlarged perspective view showing another embodiment provided with a turning-up prevention means.

FIG. 18 is a partially enlarged perspective view showing another embodiment provided with a turning-up prevention means.

FIG. 19 is a schematic side sectional view illustrating a conventional ground improvement work.

[Explanation of symbols]

 1 Hull 2 Vertical drain member 2a, 8a Core body 2b, 8b Filter 3 Center well 4 Turret structure 5 Mandrel 6 Underwater guide 7 Laying member 8 Horizontal drainage member 9, 11 Drum 10 Ground reinforcement member 12 Sewing device 13 Laying frame body 14 Drawer device 15 Cutting device 16 Fixing member attaching device 18 Pin type fixing member 19 Clip type fixing member 20 Ring type fixing member 21 Donut type fixing member 22 Joining member 23 Joining member 25 Guide post 27 Placing device 28 Rail member 30 Soft ground 32 chains 34 anchor plates

Claims (3)

[Claims] 1. A laying member having a strip-shaped horizontal drainage member is horizontally arranged on a laying surface, and the laying member arranged horizontally is vertically penetrated so that the vertical drainage member is vertically arranged in a laying surface groundwork. Embedding, the vertical drainage member facing the laying member is provided with means for preventing the laying member from being turned upside down, and the laying member is continuously laid on the laying surface by repeating a series of these operations. A method for laying a horizontal drainage member at the bottom of the water, which is characterized in that 2. A laying member holding means for holding a laying member in which a strip-shaped horizontal drainage member and a net-shaped ground reinforcing member are integrated so as to be able to be drawn out, and laying for laying the laying member horizontally on a laying surface. Laying member drawing means for drawing a member from the laying member holding means, and a vertical drainage member embedded vertically in a laying surface ground by vertically penetrating a laying member horizontally arranged on the laying surface. An apparatus for laying a horizontal drainage member at the bottom of the water, comprising: a means for preventing the vertical drainage member facing the laying member from being turned up. 3. A hull, and a laying frame body provided on the hull so as to be able to descend in water below the hull, wherein the laying member holding means and the vertical drainage member embedding means are provided on the hull. The laying device for a horizontal drainage member at the bottom of a water according to claim 2, wherein the laying member drawing-out means is provided in the laying frame body, and the turning-up preventing means is provided in the vertical drainage member embedding means. .