JPH05280054A - Reinforcement soil method and device of plate anchor type for double shut embankment - Google Patents

Abstract

PURPOSE:To suppress effectively the shearing deformation of the soil and sand as stopping, enhance the stability of the constructed embankment and also the reliance upon the works executed, and save the costs of executing works to a great extent. CONSTITUTION:Sheet piles are driven parallel in two rows 1, 2 to build double structural sheet pile works, and the upper parts of the two rows are coupled by tie rods 3. The space between these rows of sheet piles is filled with the soil and sand S as stopping, and in the under-part inside of one of the sheet pile rows 1, a plate anchor 5 is embedded being oriented as against the direction in which the soil and sand deforms. This plate anchor is tied by a wire rope 6 with the over-part of the other sheet pile row 2 so as to suppress the shearing deformation X of the soil and sand. Thus plate anchor type reinforcement soil devices 5, 6 are installed and constructed. When the double shut embankment is to be dismantled, the plate anchor 5 is removed and collected using the wire rope 6. The plate anchor 5 is equipped with a plurality of check plates 5a, 5b which are arranged against the direction in which the soil and sand as stopping makes compressive and shearing deforomation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate anchor for a double cut-off wall, which is constructed to separate the foundation of the structure from surrounding water when constructing various structures in the sea or river. Type reinforced earth construction method and device.

[0002]

2. Description of the Related Art The above-mentioned double cut-off dam is generally adopted when constructing a large-scale dam body in deep water. For example, in FIG.
As shown in Fig. 2, steel sheet piles are laid in two rows at intervals on the seabed and the river bed G and built in the sheet pile rows 1 and 2, and the upper portions of the sheet pile rows 1 and 2 are connected by the tie rod 3 to form the sheet pile row 1 , Soil layer is filled between 2 to form a medium-filled sediment S layer to build a double cut-off levee body, and as the water level inside the sheet pile row 2 is gradually decreased, the beams and bellows are gradually raised. Is installed.

As shown in FIG. 5, the above-mentioned double cut-off dike includes the earth pressure and residual water pressure Psw of the earth and sand S, the earth pressure (passive earth pressure) Pe of the ground, the water pressure Pw, and the tension of the tie rod 3 and the like. When the load is applied, the sheet pile rows 1 and 2 and the filling sand S are integrated to form a kind of composite structure that resists external force. Further, since the stability of the bank body is greatly influenced by the shear strength of the medium soil S, sand or gravel having a good grain size combination that is expected to have high shear strength is applied to the medium soil. Therefore, when cohesive soil such as dredged soil or excavated soil is mixed, the internal friction angle of the inner filling material is extremely reduced and the shear strength is greatly reduced, and the compressive deformation and uneven load due to the self-weight of the inner filling material Shear deformation due to is easy. That is, it is easily deformed by fluctuations in water pressure, fluctuations in external pressure due to drainage of water inside the bank, excavation, etc., and this bank becomes unstable and easily destroyed. For example, when the water pressure Pw on the left side becomes an unbalanced load due to drainage on the right side in the figure, the inner filling soil S is sheared and deformed in the direction of the arrow and easily falls as indicated by the dotted line. If necessary, the bank body is provided with a stabilizing measure such as further placing a steel sheet pile, arranging sand in the lower part of the sheet pile row, or reinforcing it with a cutting beam.

[0004]

SUMMARY OF THE INVENTION The conventional double breakwater is
In order to stabilize the levee body, it is necessary to use sand and gravel with a good grain size mixture that can be expected to have a large shear strength as medium-filled soil.
Considering that this levee body is a temporary structure, dredged soil,
It is desired to use economically advantageous construction by using locally procurable earth and sand such as excavated soil as the medium earth and sand.
However, this causes a problem in the stability of the bank.

The present invention was developed in order to address the above-mentioned problems, and the object of the present invention is to effectively suppress the shear deformation of the medium-filled earth and sand, and (EN) It is an object to provide a plate anchor type reinforced earth work method and device for a double cut-off dam, which improves stability and construction reliability and enables significant reduction in construction costs.

[0006]

SUMMARY OF THE INVENTION In the present invention, a sheet pile is made into a parallel plate.
Pile them in a row and build them in a double sheet pile row, connect the upper parts of both sheet pile rows with tie rods, fill the space between the two sheet pile rows with sand and fill the lower part of the inside of one sheet pile row. As a plate anchor-type reinforced soil device that embeds plate anchors facing each other in the direction of deformation of the filled soil and connects the plate anchor and the upper part of the other sheet pile row with a wire rope to suppress shear deformation of the filled soil. The built-in construction further facilitates the construction of the dam body by removing the plate anchors by the wire rope and collecting them when dismantling the double-damage dike, and at the same time effectively shears and deforms the filling soil. It suppresses and stabilizes the bank, and facilitates its removal and recovery.

Further, the plate anchor type reinforced soil device is provided with a plurality of restraining plates which are embedded in the lower portion of the intermediate filling soil and which are arranged so as to face each other in the deformation direction of compression and shear of the intermediate filling soil. It consists of a plate anchor and a wire rope that connects the plate anchor and the upper part of the sheet pile row. The anchor performance is enhanced to further improve the shear deformation suppression performance and reliability of the filled soil.

[0008]

[Operation] Along with the construction of two parallel rows of sheet piles, connecting the tiles between the tops of the sheet pile rows, and filling of the middle filling soil, a plate anchor is embedded in the inner lower part of one of the sheet pile rows facing the deformation direction of the middle filling soil. Then, the plate anchor and the upper part of the other sheet pile row were connected with a wire rope and incorporated as a plate anchor-type reinforced soil device that suppresses shear deformation of the filled soil, and it was easily constructed on a double cut-off wall and had an unbalanced load. The plate anchor exerts an excellent anchoring force under the strong earth pressure during shearing deformation of the medium-filled earth and sand, and the anchoring force suppresses the shearing deformation of the middle-filled earth and sand to the other sheet pile row via the wire rope. As a result, the shear deformation of the medium soil is effectively suppressed, the shear strength is greatly increased, and the stability and construction reliability of the double levee are significantly improved. Plates anchor the rope easily removed and recovered.

Further, the plate anchor comprises a plurality of restraining plates arranged so as to face each other in the compressing and shearing deformation directions of the filled soil, and each restraining plate receives a strong earth pressure and has a strong anchoring force. It further enhances the performance of suppressing the shear deformation of the filled sand and the reliability.

[0010]

[Embodiment] FIG. 1 shows an embodiment of a plate anchor type reinforced earth construction method and apparatus for a double levee of the present invention, FIG. 2 (A) (B)
Fig. 3 shows each embodiment of the plate anchor type reinforced soil device, Fig. 3 shows the operation of the device, and Fig. 4 shows each embodiment of the plate anchor. In the drawing, reference numerals 1 and 2 denote a sheet pile row in which piles of steel sheet piles (steel sheet piles) are laid in parallel on the seabed or river bed G, and 3 is a steel rod connecting the upper portions of the sheet pile rows 1 and 2, Tie rods such as wire ropes, 5 is a plate anchor having a horizontally oriented restraining plate 5a and a vertically oriented restraining plate 5b, and 6 is a link between the plate anchor and the upper part of the sheet pile (steel sheet pile). A wire rope is installed, 7 is a fastening member at the upper end of the wire rope, S is a filling soil, 5 and 6 are plate anchor type reinforced earth devices, and a sheet pile is attached to the seabed or riverbed G as shown in FIG. (Steel sheet pile) is laid along a guide frame (not shown) with high precision in parallel folding screens and built into double sheet pile rows 1 and 2 with excellent watertightness, and between the upper portions of the sheet pile rows 1 and 2. Connect the tie rods 3 at appropriate intervals and fill the piles S between the sheet pile rows 1 and 2. As well as, embedded in the plate anchor 5 inside bottom of one sheet pile row 1 is opposed to the deformation direction of Chutsume sand S, the plate anchor 5
And the upper part of the other sheet pile row 2 are connected by a wire rope 6 in a tensioned state to suppress the shear deformation of the filling soil S and are incorporated as a plate anchor type reinforced soil device 5, 6 It is a plate anchor type reinforced earth method.

The piles of sheet piles 1 and 2 are built by removing obstacles such as the seabed and riverbed G, soft soil, etc., and the steel sheet piles are guided along a robust guide frame, preferably a folding screen. It is struck and built with high precision, and it is laid to the desired rooting length according to the condition of the ground, water changes inside the deadline, excavation, etc. In addition, the medium-filled earth and sand S filled between the sheet pile rows 1 and 2 is a good sand with a particle size mixture that is expected to have a large shear strength,
Gravel is preferable, but since shear deformation is effectively suppressed in the present invention, dredged soil, excavated soil, etc. can be used as needed, and filling of medium filling sand S and plate anchor type reinforced soil equipment are possible. The assembling of 5 and 6 is carried out in parallel. For example, as shown in FIG.
Is applied as an unbalanced load, the plate anchor 5
Is placed at a space of about 1 m with respect to the sheet pile row 1 at or near the water bottom ground G at the lower inner side of the sheet pile row 1 and arranged in parallel as shown in the figure so as to oppose the deformation direction of the filling sand S. Is buried in the middle filling soil S and its plate anchor 5
A preload L is applied to the wire rope 6 connected to the wire rope 6 to bring the wire rope 6 to a desired tension, and the wire rope 6
The upper end of the sheet pile is connected to the upper part of the other sheet pile row 2 by a fastening member 7 to be incorporated as plate anchor type reinforced soil devices 5 and 6. A large number are arranged in parallel at appropriate intervals. The upper end of the wire rope 6 and the upper part of the sheet pile row 2 are preferably filled with sand S
It is fixed between the top and the maximum water level of the middle filling soil S where the shear deformation of the layer is maximum.

The plate anchor type reinforcing soil devices 5 and 6 are
As described above, the plate anchor 5, the wire rope 6, etc. are used.
It is equipped with restraint plates 5a, 5b (vertical direction and horizontal direction in the drawing) that enhance the opposition to the direction of compression deformation and shear deformation, and are formed to have a length of about 1 to 2 m according to the scale of the double levee. In the case of a relatively long length, both ends of the wire rope 6 are connected to the front end edge of the plate anchor 5 with an appropriate means, as shown in FIG.
Stabilize the embedding direction of a and 5b, and if relatively short,
As shown in FIG. 2B, one end of the wire rope 6 is connected to the front end edge of the plate anchor 5 by an appropriate means. further,
As shown in FIG. 4 (A), the inhibition plate 5a and the inhibition plate 5
b connected in a cross shape, a structure in which the inhibition plate 5b is connected on one end of the inhibition plate 5a as shown in FIG. 4B, and a inhibition plate at one end of the inhibition plate 5a as shown in FIG. 4C 5b is a structure in which the intermediate portions are connected, or FIG.
As shown in (D), the restraint plate 5a has a structure in which the restraint plate 5b is connected to the middle portion of the restraint plate 5a, and is appropriately selected and used in accordance with the earth and sand material, shape, scale, etc. of the middle layer of earth and sand S layer. It

The above-mentioned plate anchor type reinforcing soil device 5,
6 is incorporated in order to suppress the shear deformation X of the filling soil S due to an unbalanced load or the like to increase the shear strength and stabilize the double levee, and the plate anchor 5 thereof is shown in FIGS. 1 and 3. As shown in the figure, it is buried in the lower part of the inner filling sand S inside the sheet pile 1 on the left side, receives a strong earth pressure due to its own weight, and its movement is effectively restrained to exert an excellent anchoring force. For example, if the right side of the drawing is drained, the left side water pressure Pw
Etc. is applied as an unbalanced load to the double levee, which causes shear deformation X of the middle sill sand S in the direction of the arrow, causing overturning and destruction of the levee body, but the middle sill sand S undergoes shear deformation X. When started, the plate anchor 5 receives a tensile force T from the upper portion of the sheet pile row 2 through the wire rope 6 in the direction of the arrow, and is deeply buried in the lower portion of the filling sand S to receive strong earth pressure, Figure 3
As described above, against the horizontal component of the tensile force T, the earth pressure Pb acting on the vertical restraining plate 5b becomes a reaction force,
The earth pressure Pa acting on the horizontal deformation suppressing plate 5a becomes a reaction force against the vertical force component of the tensile force T in the vertical direction, and the plate anchor 5 receives the strong reaction force, that is, the strong anchor. The force is exerted to prevent the sheet pile row 2 from being tilted through the wire ropes 6 to effectively suppress the shear deformation X of the filling soil S and significantly increase the shear strength of the filling soil S. In addition, when the underwater work done inside the double cut-off wall is completed, the inside is filled with water and the filled sand S is taken out.
The plate anchors 5 are also sequentially taken out by the wire rope 6, and can be easily and quickly withdrawn and collected, and the tie rods, sheet piles, etc. are also withdrawn.

Since the shear strength of the medium-filled soil is effectively increased as described above, not only sand and gravel having a good grain size composition, which is expected to have high shear strength, but also dredged soil, excavated soil, etc. are used in large quantities. However, the shear strength of the double levee is ensured and it has excellent stability, and the plate anchor type reinforced soil device is arranged at appropriate intervals in the length direction of the double levee. It is easily installed in the levee body, and the relatively simple mechanism eliminates the need for a safety mechanism of the conventional complex mechanism, and it is easy and quick to construct, which enables significant cost savings. And so on.

The plate anchor type reinforced soil device is
Various plate anchors such as those shown in Fig. 4 are selected and used according to the scale of the double cut-off bank and filling sand, etc., and a plurality of plate anchors can be connected or each sheet pile row can be used as required. It is also possible to design side by side to prevent shear deformation of the middle soil in two directions.

[0016]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, the plate anchor type is used for suppressing the shear deformation of the middle stuffed earth, as well as the construction of the parallel two rows of sheet piles, the tied connection between the upper parts of the piles, the filling of the middle stuffed soil. The reinforced soil device is easily built into the double levee, and the plate anchor type reinforced soil device is easily incorporated into the double levee by a relatively simple mechanism, and the plate anchor has strong earth pressure. The movement of the wire rope is effectively restrained and exerts an excellent anchoring force, which effectively suppresses the shear deformation of the filling soil and greatly increases its shear strength to stabilize the dam body, and the wire rope Allows the plate anchors to be easily removed and recovered,
Further, the plurality of restraint plates of the plate anchors exert a stronger anchoring force to further enhance the restraint performance and reliability of the shear deformation of the filled soil, and the use of dredged soil or excavated soil as described above. The construction is easy and quick, and the stability and construction reliability of the double cut-off dike are significantly improved, and significant cost savings are possible.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a plate anchor type reinforced earth method and device for a double cut-off dam of the present invention.

FIG. 2 is perspective views (A) and (B) showing examples of the plate anchor type reinforced soil device.

FIG. 3 is an enlarged sectional view of an essential part for explaining the action of the plate anchor type reinforced soil device.

FIG. 4 is a side view (A) to (D) showing each embodiment of the plate anchor.

FIG. 5 is a sectional view showing a conventional example of a double cut-off dam.

[Explanation of symbols]

 1, 2 Sheet pile row 3 Tirotod 5 Plate anchor 5a, 5b Restraint plate 6 Wire rope 5, 6 Plate anchor type reinforced soil device S Middle filling sand X Shear deformation

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsunetaro Iwabuchi 22-7 Sanbancho, Chiyoda-ku, Tokyo Sanbancho Sekino Building 3rd Floor Japan Construction Industry Management Association

Claims (3)

[Claims] 1. Pile piles are piled in parallel to form double piles, and the upper portions of both piles are connected by a tie rod to fill the middle piles with sand. , Embedding a plate anchor in the lower part of the inside of one of the sheet pile rows so as to face the deformation direction of the filling soil, and connecting the plate anchor and the upper portion of the other sheet pile row with a wire rope Plate anchor type reinforced earth construction method for double anchorage, which is built as a plate anchor type reinforced earth device that suppresses shear deformation. 2. The plate anchor type reinforced earth work method for a double dyke according to claim 1, wherein the plate anchor is removed by the wire rope when the double dyke is dismantled and recovered. Plate anchor type reinforced earth method for heavy dykes. 3. A plate anchor type reinforced earth device applied to the plate anchor type reinforced earth method for a double levee according to claim 1 or 2, wherein the medium anchored earth and sand is buried under the middle stuffed earth and sand. A plate anchor having a plurality of restraint plates arranged to face each other in the deformation direction of compression and shear, and a wire rope connected between the plate anchor and the upper part of the sheet pile row. Double anchorage plate anchor type reinforced soil device.