JP7284720B2 - steel guide wall - Google Patents

Description

The present invention relates to construction technology for steel guide walls.

When digging a deep groove in the construction ground for continuous wall construction work, etc., when constructing a guide wall to protect the topsoil part and prevent the excavated groove from collapsing, and to guide equipment such as excavation drills. There is
With reference to FIG. 3, construction of a guide wall with reinforced concrete when the ground is soft will be described.
When constructing the guide wall 30 on the soft ground, first, the trench wall protection 11 is constructed in a predetermined area in the ground. The trench wall protection 11 is formed by soil mortar (mixing soil and solidifying material), for example, by mixing and agitating in-situ soil and solidifying material (using, for example, a multi-shaft kneading excavator or the like).
The main purpose of the ditch wall protection 11 is to keep the excavated ditch wall stable during the period from excavation while preventing the ground from collapsing, erecting a reinforcing bar cage, and pouring concrete. The installation area of the ditch wall protection 11 varies depending on the construction conditions (ground, groundwater, shape and depth of the excavated ditch wall, surcharge from excavating machinery, etc.), etc., but it is common to provide the ditch wall protection 11 on the side of the excavated ditch wall. The installation area is determined by stability calculation calculated based on the construction conditions.

Next, an area where the guide wall 30 is to be installed is excavated. Leveling concrete (not shown) is placed at the bottom of the excavated area (space), reinforcing bars 14 are assembled on the leveling concrete, and formwork 15 is installed.
Concrete 13 is placed outside the formwork 15 (both left and right sides in the plane of the drawing). Since the reinforcing bars 14 have already been placed, the guide wall 30, which is a reinforced concrete structure, is constructed by placing the concrete 13 in this step.

On the other hand, if the ground is relatively strong, instead of constructing trench wall protection, the surface of the construction area may be improved. Surface layer improvement is performed, for example, on a predetermined region from the ground surface to a depth of about 2 m. Shallow layer improvement is performed, for example, by excavating in-situ soil, mixing it with a solidifying material, and then backfilling it in the original location.
Then, the area where the guide wall should be installed is excavated to the required scale. The subsequent procedure for constructing the guide wall 30 is the same as the procedure for the groove wall protection 11 described above.

The reason why a reinforced concrete structure is constructed as the guide wall 30 in the above-described prior art is that a heavy track belt of an excavator for constructing a continuous wall is placed on the guide wall. For example, a drill for constructing a continuous wall that constitutes an excavating machine weighs about 30 tons, and the entire excavating machine is even heavier. The guide walls are thereby subjected to a great deal of load, which makes it difficult to reliably support the excavating machine unless the guide walls are of solid construction, especially if the ground below is soft.
In addition, during excavation, the grooves (excavated areas) between the guide walls are filled with bentonite (mud water). Since the bentonite water level fluctuates, both inner surfaces of the groove are likely to collapse. This is also the reason why the guide wall 30 is constructed with reinforced concrete having excellent strength.

However, the reinforced concrete guide wall 30 as described above requires a number of days for concrete curing, which increases the number of construction days and construction costs.
Moreover, after the construction of the continuous wall, it is necessary to remove the cast reinforced concrete guide wall 30, but removing the reinforced concrete requires a great deal of labor and costs enormous costs. Furthermore, the removed reinforced concrete must be treated as industrial waste, which requires labor and cost.

Here, there are techniques for constructing guide walls with steel instead of reinforced concrete structures (see Patent Documents 1 to 3).
However, in the conventional technologies (Patent Documents 1 to 3), the configuration of the constituent members is complicated, and a great deal of labor is required for assembly and removal. There is a problem that the cost of removal will rise.

JP-A-60-156825 Japanese Utility Model Laid-Open No. 4-4926 JP-A-6-180011

The present invention has been proposed in view of the above-mentioned problems of the prior art. It is intended to provide a guide wall.

The steel guide wall (20) of the present invention is a steel guide wall that is placed along both sides of a planned excavation opening construction site for constructing a continuous wall in an area below the ground level where the heavy excavator operates. There is
Shaped steel (1: H-shaped steel, C-shaped steel, for example) in which webs are installed vertically along both sides of a scheduled excavation opening construction site for continuous wall construction;
a first connecting member (bh: bolt/nut, for example) that connects adjacent shaped steels (1);
A plate (5) connected to the web of the shaped steel (1) by a second connecting member (6: tie rod, for example) inserted through the web and closing the open cross section between the upper and lower flanges;
A lower iron plate (3) on which the shaped steel (1) is placed;
The lower iron plate (3) and the third connection member (2: for example, clamping fitting) that connects the shaped steel (1).

In the present invention, it is preferable to have a reinforcing member (7: jack, for example) installed between the upper and lower flanges of the shaped steel (1) to support the load of the web (1A).

According to the present invention having the above configuration, it is not necessary to place reinforced concrete. Therefore, concrete curing is not required, and the construction period can be shortened accordingly, and the construction cost is also reduced.

In addition, when removing the steel guide wall (20) after construction (for example, continuous wall construction method), there is no need to lift the reinforced concrete, so the labor and cost required for removing the reinforced concrete can be reduced. Furthermore, there is no need to dispose of the concrete that constitutes the reinforced concrete as industrial waste, and labor and costs can be reduced accordingly.
In addition, according to the present invention, there is no need to use a special dedicated member, and there is no need to manufacture the dedicated member. In addition, it is easy to assemble and dismantle because it is a connection structure using bolts, nuts, tie rods, and clamping metal fittings, and it is possible to reuse the shape steel and connection members after dismantling. Therefore, construction costs are reduced.

Furthermore, in the present invention, if the reinforcing member (7) is arranged in the shaped steel (1) to reinforce the web for earth retaining material, the load of the equipment necessary for construction (for example, a heavy excavator) can be transferred to the steel guide. Even if it acts on the wall (20), it is possible to prevent inconveniences such as buckling or deformation of the web (1A) of the shaped steel (1).

1 is a front view of a steel guide wall according to a first embodiment of the present invention; FIG. FIG. 2 is a partially enlarged view of a single-stage section steel according to the first embodiment; It is an explanatory view showing a guide wall made of reinforced concrete according to the prior art.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG.
The embodiment shown in FIG. 1 is applied when the ground below the steel guide wall is soft.
The excavating machine used for constructing the continuous wall includes, for example, an excavating drill (not shown) and track belt 52 . A drilling drill weighs, for example, about 30 tons and one track belt of the drilling machine is heavily loaded.
Therefore, the steel guide wall 20 according to the embodiment is required to have a strong structure capable of supporting such a large load.
In the illustrated embodiment, H-shaped steel is exemplified as the shaped steel 1 .

In FIG. 1, the steel guide wall 20 continuously constructed in the direction perpendicular to the paper surface is a first connection member bh ( For example, bolts and nuts), the lower iron plate 3 on which the shaped steel 1 is placed, the filler 4 (for example, high quality soil) filled in the area above the lower iron plate 3, the reinforcing member 7 for the shaped steel 1 (for example, jack), an upper iron plate 9 arranged above the shaped steel 1, and a groove wall protection 11 constructed below the lower iron plate 3.

In FIG. 1, on the left side of the opening 20-A of the steel guide wall 20, the shaped steel 1 is arranged in two rows and two rows. On the right side of the opening 20-A, on the other hand, two rows of shaped steel 1 are arranged.
The shaped steel 1 located in the upper stage and the shaped steel 1 located in the lower stage are connected by a first connecting member bh. For simplification of the drawing, the first connection member bh is indicated by a dashed line.
When using a commercially available product in which holes are provided in advance at a predetermined pitch on the flange surface of the shaped steel 1, the holes can be used as insertion holes. Steel 1 can be fastened together. Since it can be used without cutting unnecessary holes, it can be reused without being damaged, as compared with products on the market that do not have holes.
1 and 2, the steel guide wall 20 extends in the depth direction (the direction perpendicular to the plane of the paper). Although not shown, adjacent shaped steels 1 are also joined in the depth direction.

In FIG. 1, the lower iron plates 3 are arranged outside the opening 20-A (both left and right sides of the opening 20-A in FIG. 1). 1 are placed respectively.
In the area on the left side of the opening 20-A, the lower steel plate 3 is connected to the shaped steel 1 below by a third connection member 2 (for example, a clamping fitting) to prevent the shaped steel 1 from overturning. It is It should be noted that a commercially available product can be used as the clamping fitting exemplified as the third connecting member 2 .
The lower iron plates 3 arranged on the left and right sides of the opening 20-A are arranged so as to extend in a direction away from the opening 20-A from the position where the shaped steel 1 is placed. A filling material 4 is filled above the existing portion.
In the illustrated embodiment, high-quality soil is used as the filler 4 . As the filler 4, improved soil obtained by adding a solidifying material to soil may be used, or soil having a high unconfined compressive strength brought from a location other than the construction site may be used. The lower iron plate 3 on which the filler 4 is placed also has the function of distributing the heavy load from the endless track belt 52 of the excavating machine.

In FIG. 1, to the left of opening 20-A, track belt 52 of the excavating machine is shown in dashed lines. In this state, the maximum weight is loaded on the left row of the two rows and two rows of shaped steel 1 on the left side of the steel guide wall 20 .
Therefore, of the two rows and two rows of shaped steel 1 on the left side of the steel guide wall 20, the internal space (between the upper and lower flanges of the shaped steel 1 A reinforcing member 7 for supporting the load applied to the web 1A (portion extending in the vertical direction) of the shaped steel 1 is provided in the space).

In FIG. 1, an upper iron plate 9 is arranged above the shaped steel 1 on the left side of the opening 20-A. In other words, the upper iron plate 9 is covered with the shaped steel 1 . The upper steel plate 9 has the function of distributing the heavy load of the track belt 52 of the excavating machine and the function of facilitating smooth movement of the excavating machine by the track belt 52 . The area in which the upper iron plate 9 is placed is determined based on the area that receives the heavy load from the track belt 52 of the excavating machine.
In the illustrated embodiment, the ground below the steel guide wall is soft, and there is a risk that the heavy excavating machine cannot be supported only by improving the surface layer. there is
After the steel guide wall 20 is constructed, the borehole in the area below the opening 20-A is filled with, for example, bentonite (not shown) in order to prevent the borehole from collapsing in the area below the opening 20-A. be.

Next, the configuration around the shaped steel 1 will be further described with reference to FIG. 2 . For simplification of illustration, only one stage of the section steel 1 on the left side of the opening 20-A in FIG. 1 is shown, and illustration of the lower iron plate 3 and the upper iron plate 9 is omitted.
In FIG. 2, plates 5 (plate-shaped members) are arranged on the left side of the left section steel 1 and on the right side of the right section steel 1, and the web 1A between the plate 5 and the section steel 1 serves as a second connection member 6 (tie-rods by bolts, etc.). The threaded portion provided on the shaft portion of the second connecting member 6 is not shown.
The plate 5 is provided to prevent the filling material 4 (see FIG. 1) and bentonite (not shown) from flowing into the internal space of the shaped steel 1 .
A head portion 6A (bolt head) of the second connecting member 6 is welded to the plate 5, and the bolt portion is inserted through a through hole formed in the web of the shaped steel 1 and fastened with a nut 6B. This prevents the plate 5 from moving relative to the shaped steel 1 .
If a commercially available product in which holes are provided at a predetermined pitch in the web 1A of the shaped steel 1 is used, the holes can be used as insertion holes. 5 can be stopped. Since it can be used without cutting unnecessary holes, it can be reused without being damaged, as compared with products on the market that do not have holes.

As described above with reference to FIG. 1, the reinforcing member 7 is arranged in the interior space of the steel section 1 as a reinforcing member for the web 1A of the steel section 1 which is heavily loaded by the track belt 52 of the excavating machine. there is The reinforcing members 7 are arranged at a pitch of 3 m, for example, in a direction perpendicular to the paper surface of FIGS. 1 and 2 . Although not shown, the reinforcing member 7 is held or fixed at a predetermined position in the internal space of the shaped steel 1 by known means.
In the illustrated embodiment, a jack is shown as an example of a reinforcing member 7 (a reinforcing member for the web 1A of the shaped steel 1) that supports the load acting on the shaped steel 1. It is selectable.
If the excavating machine used has a boom and the excavating drill is lowered from the boom to the construction area to excavate the area (so-called "crawler crane"), the track belt is made of steel. The steel guide wall 20 is not located near the steel guide wall 20 and the steel guide wall 20 need not support the load of the excavating machine (crawler crane).
As such, the reinforcement member 7 can be omitted if the steel guide wall 20 does not bear the weight of the excavating machine.

Although not shown, it is possible to fill the internal space of the shaped steel 1 with a padding, for example Styrofoam. This is to prevent earth and sand from entering the internal space of the shaped steel 1 by filling stuffing such as polystyrene foam when the plate 5 is omitted.
Note that the stuffing is not limited to polystyrene foam, and can be selected from shape-variable and lightweight materials.

Next, a procedure for constructing the steel guide wall 20 shown in FIG. 1 will be described. First, the groove wall protection 11 is constructed in the area below the steel guide wall 20 construction site, and after the groove wall protection 11 is constructed, the area where the steel guide wall 20 is to be installed is excavated.

Then, the position of the opening 20-A of the steel guide wall 20 is determined, the lower iron plate 3 is laid on both left and right sides of the opening 20-A, and the shaped steel 1 is installed on the lower iron plate 3. As described above, the steel sections 1 are arranged in two rows and two rows on the left side of the opening 20-A, and the steel sections 1 are arranged in two rows and one row on the right side of the opening 20-A. When installing the shaped steel 1, the shaped steels 1 are connected to each other by the first connection member bh.
A reinforcing member 7 is arranged in the internal space of the shaped steel 1 . Then, in the left and right shaped steels 1 of the opening 20-A (the left shaped steel 1 for the left region of the opening 20-A), the opening ends on the side distant from the opening 20-A are closed with the plate 5. , the web 1A of the section steel 1 and the plate 5 are connected by means of a second connecting member 6; Then, in the left and right shaped steels 1 of the opening 20-A (the right shaped steel 1 for the left region of the opening 20-A), the opening end on the side contacting the opening 20-A is closed with the plate 5. , are connected to the section steel 1 by means of a second connecting member 6 .

In the next step, the area above the lower steel plate 3 on the side of the section steel 1 closed by the plate 5 is filled with a filler 4 . After the filling material 4 is filled, it is compacted by, for example, a rolling compactor.
After filling the filler material 4 , an upper iron plate 9 is arranged in a region extending from above the shaped steel 1 to the surface of the filler material 4 .

Constructing the steel guide wall 20 according to the embodiment shown in FIG. 1 eliminates the need to place reinforced concrete. Therefore, concrete curing becomes unnecessary, and the construction period can be shortened accordingly, and the construction cost is also reduced.
In addition, when removing the steel guide wall 20 after constructing the continuous wall, there is no need to remove reinforced concrete, chipping work such as removal of reinforced concrete is unnecessary, and labor and cost can be reduced. Furthermore, there is no need to dispose of concrete as industrial waste, which reduces labor and costs.

In addition, since the steel guide wall 20 is constructed by combining the shaped steel 1, the connection members bh, 6, 2, the lower iron plate 3, and the plate 5, there is no need to manufacture and use dedicated members, and a dedicated The construction cost is reduced by the cost of manufacturing the member.
In addition, it is easy to assemble and dismantle because it is a connection structure using bolts, nuts, tie rods, and clamping metal fittings, and it is possible to reuse the shape steel and connection members after dismantling.

In addition, the open end of the shaped steel 1 on the side away from the opening 20-A was closed with the plate 5, and the web 1A of the shaped steel 1 and the plate 5 were connected with the second connection member 6, so that the shaped steel It is possible to prevent the earth and sand and the filler 4 from flowing into the space inside 1. Then, the open end of the shaped steel 1 on the side contacting the opening 20-A was closed with the plate 5 and connected to the web 1A of the shaped steel 1 with the second connecting member 6, so that bentonite was added to the space inside the shaped steel 1. can be prevented from flowing in.
Furthermore, by arranging the reinforcing member 7 in the internal space of the shaped steel 1, even if the endless track belt 52 of the excavating machine is placed on the steel guide wall 20, the web 1A of the shaped steel 1 is prevented from buckling or deforming. I can.
Further, since the upper iron plate 9 is laid above the shaped steel 1, the load of the endless track belt 52 can be dispersed.
Furthermore, even if the ground at the construction site is soft, by constructing the groove wall protection 11 below the lower iron plate 3, it is possible to resist the heavy load of the excavating machine.

In the embodiment shown in FIG. 1, the ground at the construction site where the steel guide wall 20 is to be constructed is soft, and the trench wall protection 11 is formed below the steel guide wall 20 .
On the other hand, if the ground is good (relatively strong) at the construction site, instead of constructing the trench wall protection 11, if the area below the lower iron plate 3 is shallowly improved, the heavy weight of the excavator can be supported. can do

If the ground at the construction site is good (relatively strong) and if the excavating machine is of a type that lowers the excavating drill from the boom into the construction area (crawler crane), the crawler track belt of the excavating machine is made of steel guides. It is not positioned near wall 20 . Therefore, instead of constructing the groove wall protection 11, the area below the lower iron plate 3 is shallowly improved, and the reinforcing member 7 in the internal space of the shaped steel 1 can be omitted.

It should be noted that the illustrated embodiment is merely an example and is not intended to limit the technical scope of the present invention.
For example, the shaped steel 1 that constitutes the steel guide wall 20 is not limited to 2 rows and 2 rows, or 2 rows and 1 row. It is often determined according to the conditions of the construction site, the load condition of the excavator, and the like.

1 ... shaped steel (for example, H-shaped steel, C-shaped steel)
1A... Web 2... Third connecting member (for example, clamping fitting)
3 Lower iron plate 4 Filler (good quality soil)
5... Plate (plate-like member)
6 . . . second connection member (for example, tie rod, bolt)
7 Reinforcing member (for example, jack)
9 Upper iron plate 11 Groove wall protection 20 Steel guide wall 20-A Steel guide wall opening 30 Guide wall bh First connection member ( bolts and nuts)

Claims (2)

A steel guide wall arranged along both sides of a scheduled excavation opening construction site for constructing a continuous wall in an area below the ground surface level where the heavy excavator operates,
Shaped steel in which webs are installed vertically along both sides of a scheduled excavation opening for construction of a continuous wall;
a first connection member that connects adjacent shaped steels;
a plate connected to the shaped steel web by a second connecting member inserted through the web and closing the open cross section between the upper and lower flanges;
a lower iron plate for placing the shaped steel;
A steel guide wall comprising the lower iron plate and a third connection member that connects the shaped steel. 2. A steel guide wall according to claim 1, having reinforcing members installed between the upper and lower flanges of the shaped steel to support loads acting on the web.

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