JP2000087356A - Stabilizing method for soil structure on soft ground - Google Patents

Abstract

PROBLEM TO BE SOLVED: To costlessly carry out a stabilizing repair for preventing settlement of a road or the like formed with an embankment on a soft ground in a short time without any traffic regulation of the road or the like on the upper face, by propulsively inserting a hollow embedding material from the external face of a soil structure on the soft ground to embed the hollow material in the soil structure. SOLUTION: A jacking device 30 for insertion of a hollow embedding pipe is arranged at a side location of a slope face 21 at the embankment side of an approach road 20 of a bridge which has settled or is expected to settle, to propulsively insert a hollow embedding pipe 40 into the slope face 21 of the embankment by the jacking device 30 and embed the pipe in the embankment. Soil penetrated in the hollow embedded pipe 40 at the same time with the embedment of the pipe is discharged to the outside of the pipe 40 to empty the hollow embedding pipe 40. In this way, many hollow embedding pipes 40 are embedded in rows at every nearly equal distance and also vertically embedded in several stages at every distance on the slope face 21 of the embankment to stabilize the soil structure on the soft ground, in the repair work for lightening the weight of an approach road 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for stabilizing an earth structure on soft ground, and more particularly, to an earth structure such as an approach road such as a bridge provided by embankment on a soft ground or an expressway. The present invention relates to a method for stabilizing an earth structure on soft ground, which is suitable for use in the present invention.

[0002]

2. Description of the Related Art It is widely practiced to lay an embankment on an existing ground and to pave the upper surface of the embankment with gravel, asphalt, or the like to provide an earth structure such as a road. In such an earth structure, if the existing ground is soft, the soft ground may be damaged by the weight of the embankment and road material laminated on the soft ground, or by the weight of a vehicle or the like passing on the road. The sinking causes a problem that the embankment sinks, and the road itself, which is paved above, sinks.

The problem of settlement of the soft ground will be described with reference to an example of an approach road to a bridge shown in FIG. The bridge 11 of the bridge 10 built on the river is the abutment 1 installed on both sides of the river.
When the abutments 12 and 12 are arranged, a plurality of concrete foundation piles 13 and 13... Made of concrete or the like are reached on the soft ground F which is the existing ground until the rock G is reached. The abutments 12, 12 are installed on the foundation piles 13, 13,.... Meanwhile, the abutment 1
On both sides of 2 and 12, on the soft ground F which is the existing ground,
An approach road 20 formed by the embankment M is provided. The embankment M is usually inclined, and a gravel D
A road material D in which b and asphalt Da are laminated is provided.

[0004] The approach road 20 to the bridge 10 as described above.
After completion, with the passage of time, the soft ground F is compressed due to the weight of the embankment M itself and the like, at the beginning of the construction, the upper part was La, but it sank and descended to Lb. By sinking, the upper surface of the approach road 20 may also sink, resulting in an unfavorable state of the function of the road.

[0005] A bridge 1 constructed on the soft ground F
0 abutment 11 is the weight of the embankment M itself and the embankment portion M
It has been reported that a so-called "lateral movement" phenomenon such as horizontal movement or inclination occurs at the time of completion or after completion due to the influence of land subsidence. This phenomenon also affects the approach road 20, and the approach road 20
As a result, undesired conditions such as sinking of the upper surface are caused.

As a countermeasure for the "lateral movement" and the like, there have been proposed (1) a method of reducing the load on the embankment (EP
S method), (2) Method to reduce the earth pressure of the embankment on the back of the abutment (Culvert method, Holding embankment method), (3) Method to increase the strength of the ground (Loading method, Consolidation method, Sand compaction pile) (4) Construction method (Pile slab construction method, pile cap construction method)
And so on.

[0007] In any of the above construction methods, when a new road is newly constructed, the aforementioned "lateral movement" after completion is predicted in advance and implemented as a countermeasure. When the road is completed and the road subsides during use or when the subsidence is expected to progress, the EPS method of (1) above, that is, embankment is generally used. The construction method to reduce the weight is being carried out.

[0008] In the EPS method, a lightweight embankment material is buried and disposed inside the embankment instead of a normal embankment.
The weight of the whole embankment is reduced by adopting the lightweight embankment material,
Since the settlement effect on the soft ground due to the embankment load is smaller than that of an earth structure such as a road including only normal embankment, it is possible to construct the earth structure in a state where the ground treatment work is reduced. . As the lightweight embankment material to be buried, a naturally occurring material such as lightweight earth and sand, granulated slag, coal ash, and incinerated ash, an artificial material such as styrene foam or cellular mortar, or a hollow structure is used. .

As the hollow structure used as a lightweight embankment material, a circular corrugated pipe, a box culvert, a hollow glass fiber reinforced plastic box, or the like is used. The hollow structure is formed by arranging a large number of the hollow structures at intervals in a horizontal direction, and covering the hollow structure with a normal embankment, thereby forming an earth structure such as a road. In order to increase the light-weight function of the hollow structure, the hollow structure may be arranged in two or more stages vertically.

[0010]

By the way, after the completion of the construction of the earth structure of the approach road 20 of the bridge 10 as described above,
When the road surface sinks due to the soft ground and the surface of the road becomes unfavorable in function, the EPS method of (1),
That is, in the case where the construction method for reducing the weight of the embankment is implemented, hitherto, the asphalt or the like on the road surface has been broken, the embankment has been dug up from the upper surface side, and the lightweight embankment material has been arranged in a lower portion of the embankment. Then, the lightweight embankment material is covered and buried again by embankment, and the surface of the embankment is paved with gravel Db, asphalt Da, or the like.

However, the repair work of the earth structure by the EPS method based on the settlement of the soft ground needs to be performed over the entire width and the entire length of the approach road, and is performed by breaking asphalt and the like on the road surface. Therefore, during the period of the repair work, it is necessary to restrict traffic such as partial or complete stoppage of the approach road 20.

[0012] In addition, the repair work of the earth structure by the EPS method is performed by breaking the road surface such as asphalt and digging up the embankment, so that the work period is long and the construction cost is high. There are many problems to be solved, such as not being able to obtain. The present invention has been made in view of the above point, and an object of the present invention is to stabilize and repair a soil structure such as an approach road of a bridge formed by embankment on soft ground, such as an approach road. It is an object of the present invention to provide a method for stabilizing an earth structure on soft ground which can be carried out in a short time at a low cost without restricting traffic on a road or the like on the upper surface.

[0013]

In order to achieve the above object,
The method for stabilizing an earth structure on soft ground according to the present invention basically includes inserting and propelling a hollow buried object from the outer surface of the earth structure on soft ground to form a hollow buried object in the soil structure. By burying, characterized in that the earth structure is reduced in weight,
A large number of the hollow buried objects are inserted and buried at predetermined intervals in the earth structure.

In the method for stabilizing an earth structure on soft ground according to the present invention, the hollow structure is inserted into and propelled from the outer surface of the earth structure while the earth structure is left as it is. Since the hollow buried object can be buried, it is not necessary to remove another structure or the like even if it is located above the structure, and it is possible to reduce the construction cost and the construction period significantly.
In a preferred specific embodiment of the method for stabilizing an earth structure on soft ground according to the present invention, the earth structure is an embankment road such as an approach road or a highway of a bridge, and the hollow buried object is , Is a reinforced plastic tube.

By applying the method for stabilizing an earth structure on soft ground according to the present invention to an embankment road such as an approach road of a bridge or an expressway, the vehicle is running on the road, Since the construction can be performed, it is not necessary to regulate the traffic of vehicles for the construction, and it is not necessary to dig a road on which asphalt is paved for the construction. By using a reinforced plastic pipe as the hollow buried object, the weight of the hollow buried object itself can be reduced, and the insertion of the earth structure into the embankment can be facilitated.

In another preferred embodiment of the method for stabilizing an earth structure on soft ground according to the present invention, the hollow buried object may be inserted into a side surface of the earth structure by the hollow buried object. Is inserted from one opening side by the pressing force of the hollow buried object insertion propulsion device, and simultaneously with the propulsion of the insertion of the hollow buried object into the side surface of the earth structure, the soil that has entered the hollow buried object is removed from the hollow buried object. It is characterized by being eliminated by an insertion propulsion device. According to the aspect, the insertion promotion of the hollow buried object into the embankment of the earth structure and the removal of the soil in the portion where the hollow buried object is buried can be performed simultaneously and easily,
Work for stabilizing the earth structure can be easily performed.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 4 show an embodiment in which the method for stabilizing an earth structure on soft ground according to the present invention is applied to an approach road of a bridge. FIG. 1 shows an embankment approach road which is an earth structure. FIG. 2 is a perspective view showing a construction state on the approach road, and FIG. 2 is a cross-sectional view showing a construction state on the same approach road as FIG. FIG. 3 is a cross-sectional view of the embankment approach road after construction of the stabilization method, and FIG. 4 is a vertical cross-sectional view of the bridge approach road of FIG.

The repair of the approach road 20 which has sunk or is expected to sunk is carried out by reducing the weight of the approach road 2.
An existing hollow buried pipe insertion propulsion device 30 (a device for an underground buried object facility) is disposed at a lateral position of the inclined surface 21 on the side of the bank M of the bank 0, and the hollow buried pipe insertion propulsion device 30 causes the hollow buried pipe insertion propulsion device 30 to operate. 40 is inserted into the embankment slope 21 and buried in the embankment M, and simultaneously with the insertion and embedding, soil that has entered the hollow embedding pipe 40 is discharged out of the hollow embedding pipe 40,
This is performed by making the hollow buried pipe 40 buried in the embankment M hollow. By repairing the approach road 20 by reducing the weight, the slope 21 of the embankment M is reduced.
In addition, a large number of the hollow buried pipes 40 are buried in rows at substantially equal intervals, and are arranged in several stages at intervals in the vertical direction.

The hollow buried object insertion propulsion device 30 is provided with a propulsion cylinder
1, a propulsion plate 32 that is moved in the front-rear direction by the propulsion cylinder 31, and an underground insertion body 33 that is inserted into the embankment M. The underground insert 33 has a leading pipe 34 disposed at the tip thereof, and a dummy pipe 3 is provided at the rear of the leading pipe 34.
5, one end of a propulsion casing tube 36 is attached and fixed to the dummy tube 35, and the other end of the propulsion casing tube 36 is so moved as to be integral with the propulsion plate 32. It is arranged in the insertion propulsion device 30.

At the outer periphery of the propulsion casing tube 36, one or a plurality of hollow buried tubes 40 buried in the embankment M are arranged at intervals.
In the case of 0, the number is sequentially increased in accordance with the length of insertion into the embankment M, and arranged continuously in the vertical direction. The distal end of the hollow buried pipe 40 is engaged with the dummy pipe 35, and an air gripper 37 is interposed between the propulsion casing pipe 36 and the hollow buried pipe 40 at a vertical interval. .
The air gripper 37 expands the tube by pressurized air, and connects the propulsion casing tube 36 and the hollow buried tube 40 so as to move integrally.

In the propulsion casing tube 36,
A soil discharge screw 39 extends from the insertion propulsion device 30 side, and when the screw 39 rotates, the soil guided from the front conduit 34 into the propulsion casing tube 36 is discharged to the insertion propulsion device 30 side. I can do it. Further, with respect to the hollow embedded object insertion propulsion device 30,
On the side opposite to the inclined surface 21 of the embankment M, a reaction force receiving body 38 that receives a reaction force at the time of insertion promotion of the insertion propulsion device 30 is provided.
It is placed with its lower part buried underground.

A method for stabilizing an earth structure on soft ground using the hollow buried object insertion propulsion device 30, that is, to the embankment M of the approach road 20 for the bridge 10 to reduce the weight of the approach road 20. The burying operation of the hollow buried pipe 40 is performed by mounting the hollow buried pipe 4 on the hollow buried object insertion propulsion device 30.
0, and the underground insert 33 is inserted into the hollow buried pipe 40.
, And one end of the hollow buried pipe 40 is connected to the dummy pipe 3 of the underground insertion body 33.
6, the propulsion cylinder 31 of the insertion propulsion device 30 is operated to move the propulsion plate 32 and the underground insert 33 toward the inclined surface 21 of the embankment M. The underground insert 33 is inserted into the embankment M from the leading conduit 34 at the head. At this time, the insertion propulsion device 30 attempts to move in the opposite direction to the embankment M side by the reaction force caused by the insertion of the underground insertion body 33 into the embankment M. The movement is blocked by 38.

By further operating the insertion propulsion device 30,
When the underground insert 33 is pushed into the embankment M, the soil enters the propulsion casing 36 from the front conduit 34. The infiltrated soil is guided toward the insertion propulsion device 30 by rotating the soil discharge screw 39 and discharged to the outside. When the insertion operation of the underground insertion body 33 is continuously performed, the leading conduit 34 of the underground insertion body 33 causes the slope of the embankment M on the side opposite to the side where the insertion propulsion device 30 is disposed. It will penetrate the surface 21. When the front conduit 34 of the underground insertion body 33 penetrates, the front conduit 34 and the dummy pipe 35 are removed from the slope 21 of the embankment M on the opposite side, and the pressure in the tube of the air gripper 37 is reduced. The propulsion casing tube 36
After separating from the hollow buried pipe 40, the propulsion casing pipe 36 and the soil discharge screw 39 are retracted toward the insertion propulsion device 30 and taken out from the embankment M.

By the above operation, the embankment 21
Only the hollow buried pipe 40 is left and buried, so that there is no soil in the hollow buried pipe 40 and a hollow is formed. When a single through-hole formed by the hollow buried pipe 40 is formed in the embankment M in this way, the insertion propulsion device 30 is moved, and the embedding work of the next hollow buried pipe 40 is performed in the same manner. In M, a large number of hollow buried pipes 40 are sequentially buried in rows in the horizontal and vertical directions.

As shown in FIG. 3, the embankment M of a plurality of hollow buried pipes 40, 40 buried in the embankment M.
The ends facing the inclined surface 21 of the
Are engaged so that insects, animals, earth and sand, etc. do not enter the interior. FIG. 4 shows a method of stabilizing an earth structure on soft ground according to the present embodiment by applying a plurality of hollow buried pipes 40 to approach roads 20 and 20 on both sides of a bridge 10.
.. Indicate the state of being buried, and an example of a specific arrangement and dimensional relationship of a large number of the buried hollow buried pipes 40, 40. .

For example, when the thickness LA of the embankment M is LA = 10
m, the length LB of the embankment M is LB = 50m,
The dimension L1 from the road surface to the hollow buried pipe 40 is L1
= 1 to 1.2 m, and when the outer diameter L2 of the hollow buried pipe 40 is about L2 = 0.8 m, the dimension L3 between the hollow buried pipe 40 and the adjacent hollow buried pipe 40 is required. To L3
= 0.6 m is good.

As an example of the hollow buried pipe 40, a reinforced plastic composite pipe is used. The reinforced plastic pipe is sandwiched between a resin mortar layer and a circumferential reinforcing layer made of glass fibers and an axial reinforcing layer. The protective layer is made of a thermoplastic resin such as a polyester resin. According to the above configuration, the hollow buried pipe 40 has a sufficient strength against a load at the time of propulsion into an earth structure because the hollow buried pipe 40 is a thin-walled pipe since the hollow buried pipe 40 has a large strength against loads in a circumferential direction and an axial direction. Demonstrate.

As described above, one embodiment of the present invention has been described in detail. However, the present invention is not limited to the above-described embodiment, and may be designed without departing from the spirit of the invention described in the appended claims. Can be variously changed. For example, in the above embodiment, the case where the stabilization method of the earth structure on the soft ground of the present invention is applied to an approach road of a bridge has been described.However, the present invention is limited to the approach road of the embankment. It can be applied to all roads such as other general roads and highways,
The present invention can also be applied to soil structures on soft ground other than roads that are required to be lightweight.

The means for propelling a hollow buried object into an earth structure such as an approach road of a bridge is not limited to the insertion propulsion apparatus of the above embodiment, and any other means may be used. Furthermore, although the hollow buried object has been described as a circular pipe, it may be rectangular, such as a box culvert, and may have any shape.

Further, the size of the hollow buried pipe is not limited to the exemplified outer diameter of 0.8 m, but may be appropriately determined in consideration of the size and weight of the earth structure. The number of the hollow buried pipes to be buried can be appropriately selected depending on how much the earth structure is desired to be lightweight. In addition, the distance between adjacent hollow buried pipes, even if the hollow buried pipe is deformed by earth pressure,
It is preferable to secure a distance that does not affect the deformation of the adjacent hollow buried pipe. Furthermore, the use of reinforced plastic as the material of the hollow buried object has been described. However, the hollow buried object is not limited to reinforced plastic, and may be a hollow buried object of another material such as concrete or iron. .

[0031]

As will be understood from the above description, the method for stabilizing an earth structure on soft ground according to the present invention can be implemented by inserting a hollow buried object from the outer surface of the earth structure while keeping the earth structure as it is. The hollow buried object can be buried inside the structure simply by doing so, so that there is no need to remove other structures, etc., even if they are on top of the structure, while reducing construction costs and shortening the construction period. enable.

Further, by applying the method for stabilizing an earth structure on soft ground according to the present invention to an embankment road such as an approach road of a bridge or an expressway, the vehicle is running on the road. Since the construction can be carried out, there is no need to restrict the traffic of the vehicle for the construction, and it is not necessary to dig up the road on which asphalt is paved for the construction.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which a method for stabilizing an earth structure on soft ground according to the present invention is applied to an approach road of a bridge according to an embodiment.

FIG. 2 is a cross-sectional view showing an application state to the approach road in FIG. 1;

FIG. 3 is a cross-sectional view showing a state of an approach road of a bridge after construction of the stabilization method of FIG. 1;

FIG. 4 is a vertical sectional view of the approach road of the bridge in FIG. 3, taken along the line IV-IV.

FIG. 5 is a longitudinal sectional view showing a state of an approach road of a bridge on soft ground where no stabilization method for an earth structure is applied.

[Brief description of reference numerals]

 REFERENCE SIGNS LIST 10 bridge 11 bridge 12 abutment 13 foundation pile 20 approach runway 21 embankment slope 30 hollow buried object insertion propulsion device 31 propulsion cylinder 32 propulsion plate 33 underground insertion body 34 front pipe 35 dummy pipe 36 propulsion casing pipe 37 air bag 38 machine stand 39 Earth removal screw 40 Hollow buried pipe 41 Reaction force receiver D Pavement part Da Asphalt Db Gravel F Soft ground G Rock M Embankment

Continued on the front page (72) Inventor Masasaku Okamoto 3300-3, Minomachi, Nishiminatomachi, Niigata, Niigata Prefecture Inside Honma Gumi Co., Ltd. (72) Eitaro Kawaura 3,300-3, Toriminomachi, Nishiminatomachi, Niigata, Niigata Prefecture Homma Gumi Co., Ltd. (72) Inventor Hiroo Morita 3300-3, Ninominato-machi, Minomachi, Niigata City, Niigata Prefecture Honma Gumi Co., Ltd. (72) Inventor Hiroyuki Saito 6-1, Shinmitsucho, Niigata City, Niigata Prefecture (72) Inventor Hiroyuki Takahashi 6-1, Shinkocho, Niigata City, Niigata Prefecture Kowanai Co., Ltd. (72) Inventor Shibata Higashi 6-1, Shinkocho, Niigata City, Niigata Prefecture Kowauchi Co., Ltd. (72) Inventor Yoshitsugu Oshima 3-4-7 Toranomon, Minato-ku, Tokyo Sekisui Chemical Co., Ltd. (72) Inventor Hideo Yamauchi 3-4-7 Toranomon, Minato-ku, Tokyo Sekisui Chemical Co., Ltd. (72) Inventor Yasuo Yamabe Shiga 75 Nojiri, Ritto-cho, Kurita-gun, Sekisui Chemical Co., Ltd. F-term (reference) 2D044 CA01 2D051 AA09 AG11 CA06 2D054 AC18 AD27 B A03 BA16 DA03 EA03

Claims (6)

[Claims] 1. A method for reducing the weight of an earth structure by inserting and burying a hollow buried object from an outer surface of the earth structure on a soft ground and burying the hollow buried object in the earth structure. Characteristic stabilization method for soil structures on soft ground. 2. The method for stabilizing an earth structure on soft ground according to claim 1, wherein a large number of said hollow buried objects are inserted and buried at predetermined intervals in said earth structure. . 3. The method for stabilizing an earth structure on soft ground according to claim 1, wherein the hollow buried object is a reinforced plastic pipe. 4. The soil structure on soft ground according to claim 1, wherein the soil structure is an embankment road such as an approach road or a highway of a bridge. Stabilization method. 5. The insertion propulsion of the hollow buried object into the side surface of the earth structure is carried out from one opening side of the hollow buried object by a pressing force of a hollow buried object insertion propulsion device. 5. The method for stabilizing an earth structure on soft ground according to any one of 1 to 4. 6. The hollow buried object insertion propulsion device, wherein simultaneously with the propulsion of the hollow buried object into the side surface of the earth structure, the soil that has entered the hollow buried object is removed by the hollow buried object insertion propulsion device. 5. The method for stabilizing an earth structure on soft ground according to 5.