JP3009845B2 - Protective material for underground diaphragm wall method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective material for an underground continuous wall method, and more particularly to a technique for preventing foreign matter from entering a joint portion of a steel panel.

[0002]

2. Description of the Related Art Underground continuous walls are used for earth retaining walls, foundation frames and the like when constructing underground structures. The construction of such a wall is generally performed by an underground continuous wall construction method, and various construction methods such as a method of embedding a steel cage or a steel box in a concrete wall are provided. When constructing an underground wall using this type of construction, when the weight of the structure is large or when the construction depth is deep, the steel underground diaphragm wall method using a steel box is generally used. Have been.

In the steel underground continuous wall method, for example, a steel box as shown in FIG. 7 is used, and a steel box is formed in combination in an excavation hole. The steel panel shown in the figure is composed of first and second members 1 and 2,
The first member 1 includes a pair of flanges 1a arranged in parallel.
And a web 1b connecting the flange 1a at the center.
And a hollow cylindrical portion 1d having slit-shaped openings 1c provided at both ends of each flange 1a.

The second member 2 has a pair of flanges 2a arranged in parallel, a web 2b connecting the flanges 2a at the center, and a hollow having slit-shaped openings 2c provided at both ends of each flange 2b. It has a cylindrical portion 2d and an arrowhead-shaped claw 2e fitted and fixed to the opening 2c of the hollow cylindrical portion 2d. The claw pieces 2e are inserted into the hollow cylindrical portion 1d of the first member 1 to constitute a joint portion, are intermittently arranged at predetermined intervals along the opening 2c, and It is provided so as to protrude outward.

When the first and second members 1 and 2 constructed as described above are to be built in the excavation hole 3, the installation position is marked on a guide wall or the like, as shown in FIG. First, the first member 1 is erected at a predetermined position, and then the claw 2e of the second member 2 is inserted between the first members 1 into the hollow cylindrical portion 1d. When the installation of the first and second members 1 and 2 is completed, a curable material 4 such as concrete is filled in the excavation hole 3 to form a rectangular panel. When forming, in order to enable joint connection between the panels, the backfill crushed stone 6 is interposed between the first member 1 located on the end side and the excavation hole 3 with the wraparound member 5 interposed therebetween. Had been filled.

However, when the backfill crushed stone 6 is filled between the first member 1 and the end of the excavation hole 3, the first member 1
Since the hollow cylindrical portion 1d serving as the joint portion is provided with the slit-shaped opening 1c, the backfill crushed stone 6 enters from the opening 1c, and the cylindrical portion 1d is closed. When the backfill crushed stones 6 enter the hollow cylindrical portion 1d, the work for removing the crushed stones requires labor and time, and the construction efficiency is reduced.

After the formation of the preceding panel, excavation for the following panel is performed as shown by the dotted line in FIG. 8, and at this time, the bit of the excavator comes into contact with the hollow cylindrical portion 1d,
There has also been a problem in that the connection is very difficult after being damaged or deformed. Therefore, for example, Japanese Patent Application Laid-Open No. 5-272131 discloses a hollow cylindrical portion 1.
An underground continuous wall construction method in which a partition plate for preventing the backfill crushed stone 6 from entering in d is provided. The partition plate disclosed in this publication has a plate portion in which both ends in the longitudinal direction are in contact with the side surface of the excavation hole 3 and the front surface is in contact with the hollow cylindrical portion 1.
And a projection inserted into the hollow cylindrical portion 1, and these are integrated. However, in the case where the backfill crushed stone 6 is prevented from entering by such means, there is a technical problem described below.

[0008]

That is, in the partition plate disclosed in the above publication, the both ends of the plate portion in the longitudinal direction are brought into contact with the wall surface of the excavation hole 3 so that the backfill crushed stone 6 can be formed by the first member 1. Although it is prevented from intruding into the side, the wall surface of the excavation hole 3 is uneven and uneven,
Intrusion of the backfill crushed stone 6 could not be sufficiently prevented.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a protective material for an underground continuous construction method capable of reliably and sufficiently preventing the penetration of backfill crushed stones. Is to provide. Another object of the present invention is to provide a protective material for an underground continuous wall method which can be easily pulled out.

[0010]

In order to achieve the above-mentioned object, according to the present invention, steel panels connected to each other through joints are erected in a rectangular excavation hole excavated in the ground. Later, in the underground continuous wall construction method in which a hardening material is filled in the excavation hole and a subsequent panel is sequentially connected to the excavation hole, the steel panel on the end side and the excavation hole are connected. When filling the backfill crushed stone between, it is a protective material interposed between the steel panel and the backfill crushed stone,
The protective material was constituted by a protective plate for covering the outer periphery of the hollow cylindrical portion constituting the joint portion of the steel panel so as to embrace the outer peripheral portion, and a protective tube inserted into the hollow cylindrical portion. According to this configuration, the protective material includes a protective plate that covers the outer periphery of the hollow cylindrical portion so as to embrace the outer peripheral portion, and a protective tube inserted into the hollow cylindrical portion. Intrusion can be reliably prevented. The protective material, a substrate portion narrower than the width of the excavation hole, one end side is fixed to both ends of the substrate portion, a curved thin plate whose inner surface side is pressed against the hollow cylindrical portion by the side pressure of the backfill crushed stone, It is provided on the other end side of this curved thin plate, and by the lateral pressure of the backfill crushed stone,
A flat plate that is pressed against a mounting plate of the wraparound prevention member provided on the steel panel. According to this configuration, since the protective material is pressed into contact with the two places, it is possible to more reliably prevent the backfill crushed stone from entering the hollow cylinder. Further, the protective material can be pulled out by a predetermined amount by a drawing-out jig provided with a jack according to the filling state of the curable material. With this configuration, the protective material can be cut off from the curable material, and the protective material can be easily pulled out.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 and 6 show an embodiment of a protective material for an underground continuous wall method according to the present invention. In the following description, portions that are the same as or correspond to the above-described conventional example are denoted by the same reference numerals.

FIG. 1 is a top view of an end side when a protective panel 20 according to the present invention is installed and a preceding panel 12 is formed by an underground continuous wall method. The preceding panel 12 forms a rectangular excavation hole 3 by a conventional underground continuous wall method while being filled with a stable liquid such as muddy water, and a joint portion (the hollow cylindrical portion 1d in FIG. 7) is formed in the excavation hole 3. The first and second members 1 and 2 are connected and built via the claw portions 2e), and thereafter, the hardening material 4 such as concrete is filled in the excavation hole 3 and formed.

The steel panel is basically the same as the first and second members 1 and 2 shown in FIG. The outer surface of each flange 1a of the first member 1 disposed at both ends is provided with a hollow cylindrical portion 1d in the connecting direction of the preceding panel 12.
A mounting plate 14 is protruded in the vicinity of. The mounting plate 14 extends along the longitudinal direction of the flange 1a and has the same length as the flange 1a.

A wraparound member 10 is fixed to one side surface of the mounting plate 14 with bolts. The wrap-around preventing member 10 includes a substrate 10a made of a thin metal plate, for example, a steel plate or a tin plate, and a flexible sheet, for example, a rubber sheet 10 attached to one surface of the substrate 10a.
b. In this embodiment, the rubber sheet 10b is attached to the substrate 1 so that the rubber sheet 10b comes into contact with the side wall surface of the borehole 3.
0a is stuck on the outer surface side.

The wraparound member 10 is bent in the vicinity of the mounting plate 14 so that the overall shape is substantially L-shaped. The backfill crushed stone 6 for enabling connection between the panels is filled between the first member 1 and the end of the excavation hole 3 in the connection direction. The material 20 is installed. The protection member 20 includes a protection plate 22 and a protection tube 24.

The details of the protection plate 22 are shown in FIGS. The protection plate 22 shown in the figure is formed to have the same length as the length of the first member 1 in the longitudinal axis direction, and has a flat plate-like substrate portion 22a having a width smaller than the width of the excavation hole 3; At both ends in the width direction of the portion 22a, a pair of curved thin plates 22b having one end fixed thereto and a pair of flat plates 22c fixed to the other end of the curved thin plate 22b are provided.

At the upper end side of the substrate portion 22a, the substrate portion 22a
A pair of reinforcing plates 22d are fixed to each other with bolts and nuts, and a connecting plate of a drawing-out jig described later is connected to the reinforced portion. Curved thin plate 22b
Are made of a flexible thin metal plate, and are arranged so as to embrace the outer periphery of the hollow cylindrical portion 1d of the first member 1, respectively.

The flat plate 22c is attached to the mounting plate 1.
4 and is disposed so as to face the mounting plate 14. The protection tube 24 is a cylindrical tube having substantially the same length as the length of the first member 1 in the longitudinal axis direction, and is inserted into the hollow cylindrical portion 1d. When the backfill crushed stone 6 is filled after the protection material 20 configured as described above is installed, as shown in FIG. 3, the inner side of the curved thin plate 22 b of the protection plate 22 is hollowed out by the filling pressure of the backfill crushed stone 6. It is pressed against the edge of the opening 1c of the cylindrical portion 1d. In addition, the backfill crushed stone 6 is also filled between the wraparound material 10 and the curved thin plate 22b, and when this portion is filled with the backfill crushed stone 6,
The curved thin plate 22b is deformed by receiving the lateral pressure of the backfill crushed stone 6.

At this time, one end of the curved thin plate 22b is fixed to the substrate portion 22a, and this portion is pressed against the edge of the opening 1c as described above.
The free end side provided with 2c moves forward. When the curved thin plate 22b moves in this manner, the flat plate 22c that is opposed to the flat plate 22b is pressed against the mounting plate 14.

Therefore, in the case of this embodiment, the protection plate 22
The curved thin plate 22b surrounds the hollow cylindrical portion 1d so as to embrace the hollow cylindrical portion 1d, so that the backfill crushed stone 6 is prevented from entering the hollow cylindrical portion 1d, and the flat plate 22c is attached to the mounting plate. 14 and the inner surface side of the curved thin pair 22b is pressed against the edge of the opening 1c of each hollow cylindrical portion 1d, so that the backfill crushed stone 6 is also prevented from entering these portions.

In the hollow cylindrical portion 1d, a protective tube 24 is provided.
Is inserted, the protection tube 24 also prevents the backfill crushed stone 6 from entering. On the other hand, when the backfill crushed stone 6 is filled, the wraparound preventing material 10 is composed of a thin metal plate substrate 10a and a rubber sheet 10b, and the rigidity of the rubber sheet 10b is reinforced by the substrate 10a. While it is prevented from being greatly deformed, it also has an appropriate flexibility, so that the tip side of the wrap-around preventing material 10 is deformed following the side wall surface of the excavation hole 3 under the lateral pressure of the backfill crushed stone 6. In close contact.

At this time, the flexible rubber sheet 10b
Abuts against the wall surface of the excavation hole 3, so that the degree of close contact between them is kept even better. Then, the curable material 4 is filled in the excavation hole 3 in such a state. When the curable material 4 is filled, the curling preventing material 10 is interposed between the curable material 4 and the backfill crushed stone 6, and the tip side thereof is in close contact with the side wall surface 3a of the excavation hole 3; 4 is reliably prevented from wrapping around the backfill crushed stone 6 side.

Here, in the case of the present embodiment, the protective material 20 is pulled out by a predetermined amount by the drawing-out jig 30 according to the filling state of the curable material 4. 4 to 6,
An example of a drawing-only jig 30 used at this time is shown. The dedicated jig 30 shown in FIG. 1 includes a plurality of jacks 34 installed on a guide wall 32 provided at the upper end of the excavation hole 3 and a pull-out table 36 supported on a telescopic plunger 35 of the jack 34. Have been.

The draw-out table 36 has a protective plate 22 on its lower surface.
A connection plate 38 is formed so as to be engaged with the protection tube 24, and a concave portion 40 for inserting the protection tube 24 is cut out on one side surface thereof. The connection plate 38 is joined by sandwiching the upper end side of the protection plate 22 and screwing a bolt and nut. The protection tube 24 is inserted into the concave portion 40, and is fixed to the pull-out base 36 by mounting a holding tool 42 having a U-bolt for tightening on the upper surface side of the pull-out base 36.

The protective material 20 is pulled up in the following procedure as the preceding panel 12 is filled with the curable material 4. First, when the curable material 4 for consolidating the preceding panel 12 is filled, the jack 34 is operated and pulled out by about 5 cm. Next, during the period in which the curable material 4 for main construction is being filled, the material is similarly pulled out about 5 cm. Also,
After the curable material 4 for main construction is filled, it is similarly pulled out by about 5 cm.

Further, after filling the curable material 4 for permanent installation, after a predetermined time, for example, 12 hours, similarly, 5c
m is pulled out. After the excavation hole for the following panel is excavated, the protective material 20 is removed by a hydraulic crane or the like.
Is completely pulled out, but a jack 34 can be used to assist the lift at the start of the pulling out.

Now, the protective material 20 constructed as described above
By using, the backfill crushed stone 6 can be reliably and sufficiently prevented from entering the hollow cylindrical portion 1d constituting the joint portion of the steel panel, so that the labor for the removal operation is reduced and the construction efficiency is improved. Also, when excavating for the following panel, the hollow cylindrical portion 1d is not damaged or deformed, so that there is no hindrance to the subsequent connection.

In the case of this embodiment, the protective material 20
Is pulled out by a predetermined amount by the dedicated jig 30 having the jack 34 in accordance with the filling state of the curable material 4 for forming the preceding panel, so that the curable material 4 and the protective material 20 are reliably cut off. Finally, it is possible to easily pull out when finally pulling out.

[0029]

As described above in detail in the embodiments,
ADVANTAGE OF THE INVENTION According to the protective material for underground diaphragm wall construction methods according to the present invention, the penetration of backfill crushed stone into the joint portion for connection can be reliably and sufficiently prevented, so that the construction efficiency can be improved.

[Brief description of the drawings]

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a top view of a main part in a construction state showing an embodiment of a protective material for an underground continuous wall method according to the present invention.

FIG. 2 is a plan view of the protective material.

FIG. 3 is an enlarged view of a main part of FIG. 1;

FIG. 4 is an explanatory side view when the protective material of the present invention is pulled out using a dedicated pulling-out jig.

FIG. 5 is a top view of the exclusive jig.

FIG. 6 is a side view of the exclusive jig.

FIG. 7 is a perspective view showing an example of a steel panel used in the steel ground wall construction method.

FIG. 8 is a plan view of an essential part showing a conventional example when a preceding panel is formed by an underground continuous wall method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st member 2 2nd member 3 Excavation hole 3a Side wall surface 4 Curable material 6 Backfill crushed stone 10 Wrap-in prevention material 20 Protective material 22 Protective plate 22a Substrate part 22b Curved thin plate 22c Flat plate 30 Jig for exclusive use of extraction 34 Jack

Continuation of the front page (72) Inventor Kazuyuki Tazaki 2-6-3 Otemachi, Chiyoda-ku, Tokyo Nippon Steel Corporation (72) Inventor Yoshimitsu Nozu 1-10-19 Higashisakura, Higashi-ku, Nagoya-shi, Aichi Prefecture (72) Inventor Jin Takahashi 1-10-19 Higashi-sakura, Higashi-ku, Nagoya-shi, Aichi Prefecture In-house Nagoya Branch (72) Inventor Nobuhiko Hayashi 1-10-19, Higashi-sakura, Higashi-ku, Nagoya-shi, Aichi (56) References JP-A-5-272131 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 5/02-5/20

Claims (3)

(57) [Claims] After a steel panel connected to each other through a joint is built in a rectangular drilled hole excavated in the ground, a hardening material is filled in the drilled hole, and a horizontal In the underground continuous wall construction method of sequentially constructing the leading and trailing panels connected in the direction, when filling crushed stone between the steel panel on the end side and the excavation hole, the steel panel and A protective material interposed between the backfill crushed stone and the protective material, wherein the protective material covers the outer periphery of a hollow cylindrical portion constituting a joint portion of the steel panel so as to embrace the outer periphery thereof, and is inserted into the hollow cylindrical portion. Protective material for underground diaphragm wall construction, characterized in that it comprises a protective pipe to be used. 2. The protection material according to claim 1, wherein the protection member has a substrate portion narrower than a width of the excavation hole, and one end side is fixed to both ends of the substrate portion.
A curved thin plate whose inner surface side is pressed against the hollow cylindrical portion by the side pressure of the backfill crushed stone, and provided on the other end side of the curved thin plate, by a side pressure of the backfill crushed stone, a wraparound preventing material provided on the steel panel. The protection material for underground continuous wall construction according to claim 1, further comprising a flat plate that is in pressure contact with the mounting plate. 3. The underground continuous wall according to claim 1, wherein the protective material is pulled out by a predetermined amount by a pulling-out jig provided with a jack according to a filling state of the curable material. Protective material for construction methods.