JPH09228363A - Protecting material for underground continuous wall construction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent entering of backfilling crushed stone. SOLUTION: A protecting material comprises a protecting plate 22 and a protecting pipe 24, and the protecting plate comprises a base part 22a, a curved thin plate 22b, and a flat plate 22c. The curved thin plate 22b is formed by a flexible metallic thin plate, and is installed in such manner that it holds an outer periphery of a hollow cylindrical part 1d of the first member. The protecting pipe 24 is inserted into the hollow cylindrical part 1b. An inner surface side of the curved thin plate 22b of the protecting plate, is closely brought into contact with an edge of an opening 1c of each hollow cylindrical part 1d, by the charged side pressure of the backfilling crushed stone, when the backfilling crushed stone is charged after the protecting material is installed. On the other hand, when the thin plate 22b is about to deform when it receives the side pressure of the backfilling crushed stone, the side where the flat plate 22c is installed, is moved forward because the end of the curved thin plate 22b is fixed to the base part 22a, and is pressed to the edge of the opening 1c. The curved thin plate 22c is thus moved, so that the flat plate 22c is pressed to the fitting plate 14.

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 construction 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 as earth retaining walls and foundation frames when constructing underground structures. Construction of such a wall body is usually performed by an underground continuous wall construction method, and various construction methods such as a method of burying a reinforcing bar cage or a steel box in a concrete wall body are provided. When constructing a continuous underground wall by this type of construction method, the steel continuous underground wall method that uses a steel box is generally adopted when the weight of the structure is large or the construction depth is deep. Has been done.

In the steel underground continuous wall construction method, for example, steel panels as shown in FIG. 7 were used to form a steel box by combining them 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 is a pair of flanges 1a arranged in parallel.
And a web 1b connecting the flange 1a at the central portion.
And a hollow cylindrical portion 1d having slit-shaped openings 1c provided at both ends of each flange 1a.

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

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

However, when the backfilled crushed stone 6 is filled between the first member 1 and the end side of the excavation hole 3, the first member 1 becomes
Since the hollow cylindrical portion 1d serving as the joint portion is provided with the slit-shaped opening 1c, the backfilled crushed stone 6 enters into the inside through the opening 1c, and the cylindrical portion 1d is closed. If the back-filled crushed stone 6 enters the hollow cylindrical portion 1d, the work for removing the crushed stone 6 takes labor and time, and the construction efficiency decreases.

After the formation of the leading panel, as shown by the dotted line in FIG. 8, excavation for the trailing panel is performed. At this time, the bit of the excavator comes into contact with the hollow cylindrical portion 1d,
There is also a problem that it may be damaged or deformed, and subsequent connection becomes very difficult. Therefore, for example, in Japanese Patent Application Laid-Open No. 5-272131, the hollow cylindrical portion 1
There is disclosed a underground wall construction method in which a partition plate for preventing the backfilled crushed stone 6 from entering the inside of 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.
The hollow cylindrical portion 1 is provided with a projecting portion that is inserted into the hollow cylindrical portion 1. However, in the case of preventing the backfilled crushed stone 6 from entering by such means, there are technical problems described below.

[0008]

That is, in the partition plate disclosed in the above publication, the back-filled crushed stones 6 are moved to the first member 1 by bringing both ends of the plate portion in the longitudinal direction into contact with the wall surface of the excavation hole 3. Although the wall surface of the excavation hole 3 has unevenness and is not a uniform surface,
Intrusion of the backfilled crushed stone 6 could not be sufficiently prevented.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a protective material for underground continuous construction method capable of reliably and sufficiently preventing the intrusion of backfilled crushed stone. To provide. Another object of the present invention is to provide a protective material for underground continuous wall construction method that can be easily pulled out.

[0010]

In order to achieve the above object, the present invention constructs steel material panels interconnected through a joint in a rectangular excavation hole excavated in the ground. Later, in the underground continuous wall construction method in which the hardening hole is filled with a curable material to sequentially construct the forward and backward panels to be connected in the lateral direction, the steel material panel on the end side and the drilling hole A protective material, which is interposed between the steel material panel and the backfilled crushed stone when filling the backfilled crushed stone,
The protective member is composed of a protective plate that covers the outer periphery of the hollow cylindrical portion that constitutes the joint portion of the steel panel by hugging it and a protective tube that is inserted into the hollow cylindrical portion. According to this configuration, the protective member includes the protective plate that covers the outer periphery of the hollow cylindrical portion so as to be wrapped therein, and the protective tube that is inserted into the hollow cylindrical portion. Intrusion can be reliably prevented. The protective member is a substrate portion having a width narrower than the width of the excavation hole, one end side is fixed to both ends of the substrate portion, and a curved thin plate whose inner surface side is pressed against the hollow cylindrical portion by lateral pressure of the backfilled crushed stone, It is provided on the other end side of this curved thin plate, and by the lateral pressure of the backfilled crushed stone,
The steel plate may be formed of a flat plate press-contacted to a mounting plate of the anti-wraparound material provided on the steel panel. According to this structure, since the protective material is pressed at two locations, it is possible to more reliably prevent the backfilled crushed stones from entering the hollow cylindrical body. In addition, the protective material can be pulled out by a predetermined amount by a pulling-out jig equipped with a jack according to the filling state of the curable material. By adopting this configuration, the protective material can be trimmed with the curable material, and the withdrawal can be easily performed.

[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 underground wall construction method according to the present invention. In the following description, the same or corresponding parts as those in the conventional example described above are designated by the same reference numerals.

FIG. 1 is a top view of the end portion side when the protective material 20 according to the present invention is installed and the preceding panel 12 is formed by the underground continuous wall construction method. The preceding panel 12 has a rectangular excavation hole 3 formed by a conventional underground continuous wall construction method while being filled with a stabilizing solution such as mud, and the joint portion (the hollow cylindrical portion 1d in FIG. 7) is formed in the excavation hole 3. And the first and second members 1 and 2 are connected to each other via the claw portion 2e), and then the excavation hole 3 is filled with a curable material 4 such as concrete.

The steel panel is basically the same as the first and second members 1 and 2 shown in FIG. Then, on the outer surface of each flange 1a of the first member 1 arranged on both end sides, the hollow cylindrical portion 1d in the connecting direction of the preceding panel 12 is formed.
A mounting plate 14 is provided in the vicinity of. The mounting plate 14 extends along the longitudinal axis of the flange 1a and has the same length as the flange 1a.

A wraparound prevention member 10 is fixed to one side surface of the mounting plate 14 with bolts. The anti-wraparound material 10 includes a substrate 10a made of a thin metal plate, for example, a steel plate or a tin plate, and a flexible sheet attached to one surface of the substrate 10a, for example, a rubber sheet 10.
b. In this embodiment, the rubber sheet 10b contacts the side wall surface of the excavation hole 3 so that the substrate 1
It is attached to the outer surface side of 0a.

The anti-wraparound material 10 is bent near the mounting plate 14 so that the overall shape is substantially L-shaped. The backfill crushed stone 6 for enabling the connection between the panels is filled between the first member 1 and the end portion side of the drill hole 3 in the connecting direction. Prior to this filling, the protection of the present invention is performed. The material 20 is installed. The protective member 20 is composed of a protective plate 22 and a protective tube 24.

Details of the protective plate 22 are shown in FIGS. The protective 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 a flat plate-shaped substrate portion 22 a having a width smaller than the width of the drilled hole 3, and this substrate. At both ends in the width direction of the portion 22a, a pair of curved thin plates 22b is fixed at one end, and a pair of flat plates 22c is fixed at the other end of the curved thin plate 22b.

On 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 sandwiched therebetween, and a connection plate of a pulling-out dedicated jig, which will be described later, is coupled 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 the mounting plate 1
It is formed narrower than 4 and is arranged so as to face the mounting plate 14. The protection pipes 24 are cylindrical pipes having substantially the same length as the length of the first member 1 in the longitudinal axis direction, and are inserted into the hollow cylindrical portion 1d. When the backfilled crushed stones 6 are filled after the protective material 20 configured as described above is installed, the inner surface side of the curved thin plate 22b of the protective plate 22 is hollowed by the filling side pressure of the backfilled crushed stones 6 as shown in FIG. It is pressed against the edge of the opening 1c of the cylindrical portion 1d. Further, the backfill crushed stone 6 is also filled between the wraparound prevention 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 receives the lateral pressure of the backfilled crushed stone 6 and tries to deform.

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, so that the flat plate 2
The free end side provided with 2c moves forward. When the curved thin plate 22b moves in this manner, the flat plate-shaped plates 22c arranged opposite to each other are pressed against the mounting plate 14.

Therefore, in the case of this embodiment, the protective plate 22
The curved thin plate 22b surrounds the outer periphery of the hollow cylindrical portion 1d so as to surround the hollow cylindrical portion 1d. Therefore, the backfilled crushed stone 6 is prevented from entering the hollow cylindrical portion 1d, and the flat plate 22c is attached to the mounting plate. Since it is pressed against 14 and the inner surface side of the curved thin pair 22b is pressed against the end edge of the opening 1c of each hollow cylindrical portion 1d, intrusion of the backfilled crushed stone 6 is prevented even in these portions.

In addition, a protective tube 24 is provided in the hollow cylindrical portion 1d.
Since the protective tube 24 is inserted, the backfilled crushed stone 6 is prevented from entering by the protective tube 24. On the other hand, when the backfilled crushed stone 6 is filled, the sneak-in prevention 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 largely deformed, it is also provided with an appropriate degree of flexibility, so that the tip side of the sneak prevention 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
Is in contact with the wall surface of the excavation hole 3, so that the degree of close contact between them can be further improved. Then, in such a state, the curable material 4 is filled in the excavation hole 3. When the curable material 4 is filled, the sneak-in prevention material 10 is interposed between the curable material 4 and the backfilled crushed stone 6, and its tip side is in close contact with the side wall surface 3a of the excavation hole 3. 4 is surely prevented from going around to the backfill crushed stone 6 side.

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

The pull-out table 36 has a protective plate 22 on its lower surface side.
A connecting plate 38 to be engaged with is projected, and a concave portion 40 for inserting the protective tube 24 is cut out on one side surface side 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 protective tube 24 is inserted into the recess 40, and is locked to the pull-out base 36 by mounting the holding tools 42 having U bolts for tightening on the upper surface side of the pull-out base 36, respectively.

The protective material 20 is pulled up by the following procedure as the curable material 4 of the preceding panel 12 is filled. First, when the curable material 4 for solidifying the preceding panel 12 is filled, the jack 34 is operated and pulled out by about 5 cm. Next, while the curable material 4 for main installation is being filled, it is similarly pulled out by about 5 cm. Also,
After filling the curable material 4 for main installation, it is similarly pulled out by about 5 cm.

Further, after the curable material 4 for main installation is filled, a predetermined time, for example, 12 hours has passed, and then 5c is similarly applied.
It is pulled out by about m. Then, after the excavation hole for the trailing panel has been excavated, a protective material 20 is provided by a hydraulic crane or the like.
However, the jack 34 can be used to assist the lift force at the start of the withdrawal.

Now, the protective member 20 constructed as described above.
By using, it is possible to reliably and sufficiently prevent the back-filled crushed stone 6 from entering the hollow cylindrical portion 1d that constitutes the joint portion of the steel material panel, so the labor of the removing work is saved and the construction efficiency is improved. Further, even when excavating for the trailing panel, the hollow cylindrical portion 1d is not damaged or deformed, so that the subsequent connection is not hindered.

Further, in the case of this embodiment, the protective material 20
In accordance with the filling state of the curable material 4 for forming the preceding panel, the dedicated jig 30 provided with the jack 34 pulls the curable material 4 by a predetermined amount, so that the edge of the curable material 4 and the protective material 20 is reliably cut off. , It becomes possible to pull out easily when finally pulling out.

[0029]

As described above in detail in the embodiments,
According to the protective material for the underground continuous wall construction method of the present invention, the intrusion of the backfilled 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 drawings]

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

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

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

FIG. 4 is a side view for explaining the process of pulling out the protective material of the present invention using a dedicated pulling jig.

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

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

FIG. 7 is a perspective view showing an example of a steel material panel used in the steel underground continuous wall method.

FIG. 8 is a plan view of relevant parts showing a conventional example when forming a preceding panel by an underground continuous wall method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st member 2 2nd member 3 Drilling hole 3a Side wall surface 4 Curable material 6 Backfill crushed stone 10 Sneak prevention material 20 Protective material 22 Protective plate 22a Substrate part 22b Curved thin plate 22c Flat plate 30 Pull-out jig 34 Jack

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kazuyuki Tasaki, Kazuyuki Tasaki, 2-6-3 Otemachi, Chiyoda-ku, Tokyo, Nippon Steel Corporation (72) Inventor Yoshimitsu Nozu 1-10 Higashisakura, Higashi-ku, Nagoya-shi, Aichi −19 Obayashi Corporation Nagoya Branch (72) Inventor Hitoshi Takahashi 1-10-19 Higashi Sakura, Higashi-ku, Nagoya, Aichi Prefecture 1-10-19 Obayashi Corporation Nagoya Branch (72) Inventor Nobuhiko Hayashi 1-10-19 Higashi-sakura, Higashi-ku, Nagoya City, Aichi Prefecture Obayashi Nagoya Branch Office

Claims (3)

[Claims] 1. After a steel material panel interconnected via a joint is built in a rectangular excavation hole excavated in the ground, a curable material is filled in the excavation hole to form a horizontal cross section. In the continuous underground wall method of sequentially constructing the forward and backward panels connected in the direction, when the backfill crushed stone is filled between the steel material panel and the excavation hole on the end side, the steel material panel and the A protective material interposed between the back-filled crushed stone and the protective material, the protective plate covering the outer periphery of the hollow cylindrical portion constituting the joint portion of the steel panel by hugging it, and being inserted into the hollow cylindrical portion. A protective material for the underground continuous wall construction method, which comprises a protective tube. 2. The protective member includes a base plate portion having a width narrower than the width of the excavation hole, and one end side fixed to both ends of the base plate portion.
A curved thin plate whose inner surface side is brought into pressure contact with the hollow cylindrical portion by the side pressure of the backfilled crushed stone, and is provided on the other end side of the curved thin plate, and by the lateral pressure of the backfilled crushed stone, a sneak prevention material provided on the steel material panel. The protective material for the underground continuous wall construction method according to claim 1, further comprising a flat plate plate that is in pressure contact with the mounting plate. 3. The underground continuous wall according to claim 1, wherein the protective material is withdrawn by a predetermined amount with a jig for withdrawal provided with a jack according to the filling state of the curable material. Protective material for construction method.