JP2003293366A - Foundation structure of windbreak wall - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the foundation structure of a windbreak wall in which a foundation for the windbreak wall is fixed on a ground without depending upon the overs and shorts of ground strength. <P>SOLUTION: In the foundation structure of the windbreak wall, a plurality of rotary press-in steel pipe piles 9 having excavating blades 9a having a diameter larger than the diameter of the piles at the lower ends of the piles are rotated and pressed into the ground, and the lower ends of each support (1 and 2) on the windward side and the leeward side in the wall 8 are connected and fixed at the upper ends of the rotary press-in steel pipe piles (9d and 9e) respectively. The inside of the pile 9 may be filled with concrete, mortar, crushed stones or sand. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a basic structure of a windbreak wall which enables stable support at low cost with a simple construction method for a wall or fence mainly used for windbreak, snowproof, sandproof, dustproof and the like.

[0002]

2. Description of the Related Art Generally, a windbreak wall is constructed by attaching a perforated steel panel or a synthetic resin net to a windbreak wall frame fixed by concrete footing. If the foundation strength of the windbreak wall is sufficient to withstand the ground, a direct foundation will be used, in which concrete is placed directly on the ground. In addition, if the ground strength is insufficient, foundation piles that support concrete footing may be placed in advance.

Since a large bending moment is generated by the load of the wind on the column supporting the windbreak wall, it is required that the foundation structure of the windbreak wall is a very solid structure. Usually, as shown in Figure 6a, the weight of the concrete footing used for the foundation of the windbreak wall is increased to address the problem of bending moment due to wind load.

However, when the load of wind is resisted by increasing the weight of the concrete footing, the load of wind also increases in proportion to the wall height of the windbreak wall. Therefore, it is inevitable when the wall height of the windbreak wall is set high. Basically, the foundation work will also become large-scale. In addition, when the ground proof strength is insufficient, as shown in FIG. 6b, the piles for supporting the concrete footing are also required, which further increases the size and complexity of the foundation work. On the other hand, as shown in FIG. 6c, when the foundation is composed of only ordinary piles, the pile length becomes very long, which is disadvantageous in terms of cost.

Further, there is room for improvement in that the large size of the concrete footing causes a large restriction when laying out the windbreak wall on the site.

[0006]

The basic structure of the windbreak wall is an essential part for stably supporting the windbreak wall, but it is only an auxiliary part for the main purpose. Nevertheless, since the wind load increases as the wind barrier height increases, the foundation becomes large in proportion to this, and problems such as an increase in the construction man-hours and layout restrictions in the foundation work occur.

The present invention has been made in order to remedy the above-mentioned drawbacks of the prior art. The purpose of the present invention is to improve the foundation structure that resists wind load by the weight of the foundation, so that it is not greatly affected by excess or deficiency of ground resistance. It is to provide a windbreak foundation structure that can fix the windbreak foundation to the ground.

Another object of the present invention is to provide a basic structure of a windbreak wall which can be installed by a simple construction method, does not restrict the layout of the windbreak wall on the site, and has a low construction cost.

[0009]

[Means for Solving the Problems] (1) The first invention is
A plurality of rotary press-fitted steel pipe piles 9 each having an excavation blade 9a having a diameter larger than the pile diameter at the lower end of the pile are rotationally press-fitted into the ground 5 to install a plurality of windward and windward side columns (1, 2). This is a basic structure of a windbreak wall in which the lower ends are connected and fixed to the upper ends of the rotary press-fitted steel pipe piles (9d, 9e), respectively. (2) The second aspect of the present invention is to install a plurality of rotary press-fitted steel pipe piles 9 equipped with excavation blades 9a having a diameter larger than the pile diameter at the lower end of the piles by rotationally press-fitting into the ground 5 to wind from the columns 1 of the windbreak wall 10. This is a basic structure of a windbreak wall in which the lower ends of the horizontal fall prevention members 12 stretched on both the upper side and the leeward side are connected and fixed to the upper ends of the rotary press-fitted steel pipe piles (9d, 9e), respectively. (3) A third aspect of the invention is the rotary press-fitted steel pipe pile 9 according to the first or second aspect of the invention, in which concrete, mortar, crushed stone, and sand are filled.

<Operation> In the basic structure of the windbreak wall of the present invention, a rotary press-fitted steel pipe pile 9 having an excavation blade 9a having a diameter larger than the pile diameter at the lower end is installed by rotary press-fitting in the ground, and windward and This is a structure in which the lower ends of the stanchions (1, 2) on the leeward side or the lower ends of the horizontal fall prevention members 12 and the upper ends of the rotary press-fitted steel pipe piles 9 are connected.
In the present invention, the couple of the excavation blade 9a attached to the lower end of the steel pipe pile 9 resists the bending moment due to the wind load.

Therefore, according to the present invention, since the foundation structure of the windbreak wall can be constructed by rotationally press-fitting the steel pipe pile 9 into the ground, large-scale excavation work is not required, and the construction period of the foundation structure of the windbreak wall and Construction costs can be significantly reduced. Further, since a large-scale concrete footing as in the conventional case is unnecessary, problems such as layout restrictions do not occur.

Further, in the present invention, the large-diameter excavation blade 9a attached to the lower end of the rotary press-fitted steel pipe pile 9 plays a large role as a pull-out resistance element, and push-in force and pull-out force are greater than those of a normal pile having the same diameter. It has excellent resistance to. Therefore, it is advantageous that the pile length can be designed shorter than the general foundation pile and the pile diameter can be designed smaller.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. 1 and 2 are views showing a windbreak wall of the first embodiment.

In the first embodiment, the legs of the truss structure in which the vertical columns 1 and the inclined columns 2 supporting the vertical columns 1 from the back side are connected by a plurality of belly members 3 are erected on the ground 5 at regular intervals. A plurality of horizontal frame members 6 extending in the horizontal direction are attached to each vertical column 1 in an orthogonal state. Then, the wall material 7 such as a perforated steel panel or a synthetic resin net is
A windbreak wall 8 is formed by being attached to the horizontal frame member 6 and the vertical support 1.

As shown in FIG. 2, the lower ends of the vertical stanchions 1 on the windward side and the inclined stanchions 2 on the leeward side are respectively ground 5.
It is inserted into the upper end of the rotary press-fitted steel pipe pile 9 which is press-fitted into. In the rotary press-fitting steel pipe pile 9 of the present invention, almost one turn of the excavating blade 9a is fixed to the lower end portion of the pile, and the rotary press-fitting steel pipe pile 9 is press-fitted into the ground 5 by, for example, a full swing type construction machine or an auger machine.

Concrete is filled and hardened at the upper end of the rotary press-fitted steel pipe pile 9 with the lower end of the vertical support column 1 or the inclined support column 2 inserted. And are connected and fixed. At this time, after the rotary press-fitting of the pile, the inside of the pile may be capped and concrete may be placed only on the upper end of the pile, or after the concrete of the rotary press-fitting steel pipe pile is filled with concrete, mortar, crushed stone, and sand, the The columns may be connected and fixed from above [not shown].

As shown in FIG. 3, the lower end of the steel pipe pile 9 in the first embodiment is notched in a spiral shape, and the steel pipe pile 9 is
The starting end and the terminating end of the spiral cutout at the lower end are connected via an arcuate step portion 9b. An excavation blade 9a is concentrically welded and fixed to the lower end of the steel pipe pile 9 along the lower end surface of the steel pipe pile 9. The excavation blade 9a is formed by partially cutting a disk-shaped (ring-shaped) steel plate having an inner diameter smaller than the inner diameter of the steel pipe and having an outer diameter larger than the outer diameter of the steel pipe in the radial direction. The cutout portion of the excavation blade 9a is fixed to the step portion 9b in a corresponding state. An excavating blade 9c is fixed by welding to the cutout one end side of the excavating blade 9a.

Further, the lower end of the pile 9 to which the excavation blade 9a is attached may be either an open end pile which is left open or a closed end pile whose end is closed. The N value of the ground, the required supporting force, the working condition, etc. Is selected as appropriate.

The configuration of the rotary press-fitted steel pipe pile described above is merely an example, and the rotary press-fitted steel pipe pile of the present invention has an excavation blade having a diameter larger than the pile diameter at the lower end, and the shape of the excavation blade is rotated. The shape is not particularly limited as long as the shape is suitable for press fitting.

The basic structure of the windbreak wall of the present invention is constructed as described above, and its operation will be described below.

In the present invention, the lower end of the vertical column 1 on the windward side and the lower end of the inclined column 2 on the leeward side are connected and fixed to the upper ends of the rotary press-fitted steel pipe piles 9, respectively. In the present invention, since the foundation structure of the windbreak wall 8 can be constructed by rotationally press-fitting the steel pipe piles 9 into the ground 5, large-scale excavation work is unnecessary, and the construction period and construction cost of the foundation structure of the windbreak wall 8 are eliminated. Can be significantly reduced.

Further, a large bending moment is generated on the windbreak wall 8 by the load of the wind. In the present invention, the rotary press-fitting steel pipe pile 9d which is windward is called pull-out resistance, and the rotary press-fitting steel pipe pile 9e which is windward is called compression resistance. Thus, the stress against the bending moment can be dealt with in the entire foundation structure using the rotary press-fitted steel pipe pile 9.

Here, when the stress due to the wind resistance acts on the pillars 1 and 2 and the pile 9, the conventional driving pile is resisted by the friction between the pile outer peripheral surface and the earth and sand, but in the present invention, it is provided at the lower end of the pile 9. The large-diameter excavation blade 9a thus formed plays a large role as a resistance element. That is, the rotary press-fitting steel pipe pile 9 of the present invention
Then, in addition to the frictional resistance between the pile outer peripheral surface and the earth and sand, the load of the earth and sand applied to the excavation blade 9a and the shear resistance of the earth and sand moved by the excavation blade 9a and the surrounding sand and sand are added. You can get the power.

In particular, since the above-mentioned shear resistance is several times larger than the frictional force between the pile outer peripheral surface and the sand in a conventional pile, the length of the pile can be greatly reduced as compared with the case of using the pile. Further, in the present invention, since the blade diameter of the excavation blade 9a can be freely set, the pile length can be further shortened by using a large blade diameter for the necessary pushing force and pulling force,
Construction costs and construction period can be shortened by significantly reducing the pile length.

As a modified example of the first embodiment, FIG.
As shown in b, the rotary press-fitting steel pipe pile 9 is press-fitted in an oblique direction according to the tilt angle of the tilting strut 2 so that the tilting strut 2 on the leeward side and the rotary press-fitting steel pipe pile 9 are linearly connected and fixed. May be. If the diameter of the excavation blade cannot be increased due to restrictions such as construction conditions, a slight footing may be added to the foundation [not shown].

<Second Embodiment> FIGS. 4 and 5a show a second embodiment.
It is the figure which showed the windbreak wall 10 of embodiment. In the second embodiment, the pillar 1 of the windbreak wall 10 is erected on the concrete footing 11, and one end of the horizontal overturning prevention member 12 connected to the rotary press-fitting steel pipe pile 9 is provided on the windward side and the leeward side of the pillar 1. It is the basic structure of the connected windbreak wall 10. In the second embodiment, the same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the second embodiment, vertical columns 1 are erected at regular intervals on a small concrete footing 11, and a plurality of horizontal frame members 6 are attached to the vertical columns 1 in an orthogonal state. A wall material 7 is attached to the material 6 and the vertical column 1. Then, on both the windward side and the leeward side of the windbreak wall 10, a horizontal fall prevention material 12 such as a steel wire or a steel rod is provided.
Are stretched respectively. One end of the horizontal fall prevention member 12 is connected and fixed to the vertical column 1, and the other end is connected and fixed to the upper end of the rotary press-fitted steel pipe pile 9 press-fitted to the windward side or the leeward side of the windbreak wall 10.

In the second embodiment, the vertical column 1 is fixed to the concrete footing 11, and is fixedly connected by the horizontal press-fitting steel pipe piles 9 which are press-fitted on the windward side and the leeward side, respectively, by the horizontal fall prevention member 12. As a result, pull-out resistance is achieved by the windward rotary press-fitting steel pipe pile 9d connected by the horizontal fall prevention member 12, and pull-out resistance is obtained by the windward rotary press-fitting steel pipe pile 9e similarly connected by the horizontal fall prevention member 12. The stress against the moment can be dealt with in the entire foundation structure using the rotary press-fitted steel pipe pile 9.

Further, in the second embodiment, the rotary press-fitting steel pipe pile 9 is used.
High resistance can be obtained by the couple acting on the excavation blade 9a. Therefore, the concrete footing 11 for fixing the vertical support 1 can be downsized as compared with the conventional example (FIG. 5b), so that large-scale excavation work is unnecessary,
The construction period and construction cost for constructing the basic structure of the windbreak wall 10 can be significantly reduced.

The second embodiment is applied to, for example, repairing the insufficient strength of the existing windbreak wall basic structure, or repairing the wall height by using the existing windbreak wall basic structure. You can also do it.

[0031]

According to the present invention, a rotary press-fitted steel pipe pile having excavation blades having a diameter larger than the pile diameter at the lower end is rotationally press-fitted and installed in the ground to prevent windward and leeward props at the lower end or horizontal overturn. It is a structure that connects the lower end of the material and the upper end of the rotary press-fitted steel pipe pile. In the present invention, since the foundation structure of the windbreak wall can be constructed by rotationally press-fitting the steel pipe pile to the ground, large-scale excavation work is unnecessary, and the construction period and construction cost for constructing the foundation structure of the windbreak wall are greatly reduced. it can. Further, since a large-scale concrete footing as in the conventional case is unnecessary, it is advantageous in that problems such as layout restrictions do not occur.

Further, in the present invention, the stress against the bending moment is dealt with in the entire foundation structure using the rotary press-fitted steel pipe piles, such as pull-out resistance on the upwind side of the vertical support and compression resistance on the down-tilt support side. be able to. In particular, in the rotary press-fitting steel pipe pile of the present invention, in addition to the friction resistance between the pile outer peripheral surface and the earth and sand, the load of the earth and sand applied to the excavation blade, and the shear resistance in the earth and sand moved by the excavation blade and the surrounding earth and sand are added, High resistance due to couple can be obtained.

Since the above-mentioned shear resistance is several times larger than the frictional force between the outer peripheral surface of the pile and the soil in the conventional pile, the pile length can be shortened as compared with the case of using the pile. Further, in the present invention, since the blade diameter of the excavating blade can be freely set, the pile length can be further shortened by using a large blade diameter for the necessary pushing force and pulling force, and the construction cost and the construction period can be greatly shortened. Can also be shortened.

Further, according to the present invention, it is possible to reduce the total amount of construction waste generated during construction by putting earth and sand or the like into the inside of the steel pipe pile, which is also advantageous in construction cost and environmental protection.

[Brief description of drawings]

FIG. 1 is a perspective view showing a windbreak wall and its basic structure according to a first embodiment.

2 (a) is a side view of FIG. 1, and FIG. 2 (b) is (a).
It is the figure which showed the modification.

FIG. 3A is a side view of a lower end portion of a rotary press-fitted steel pipe pile according to the present invention, and FIG. 3B is a vertical cross-sectional view of FIG.

FIG. 4 is a perspective view showing a windbreak wall and its basic structure according to a second embodiment.

5A is a side view of FIG. 4, and FIG. 5B is a side view of a conventional example.

6 (a) to 6 (c) are side views showing a conventional windbreak wall and its basic structure.

[Explanation of symbols]

1 vertical support 2 inclined support 3 belly materials 5 ground 6 Horizontal frame material 7 Wall material 8 wind barriers 9 Rotary press-fit steel pipe pile 9a Excavation blade 9b Step portion 9c drilling blade 9d Windward rotary press-fit steel pipe pile 9e Downwind side rotary press-fit steel pipe pile 10 windbreak 11 Concrete footing 12 Horizontal fall prevention material 13 piles

Claims (3)

[Claims] 1. A plurality of rotary press-fitted steel pipe piles having excavation blades having a diameter larger than the pile diameter at the lower end of the pile are installed by rotary press-fitting into the ground,
A basic structure of a windbreak wall in which the lower ends of the upwind and downwind columns of the windbreak wall are connected and fixed to the upper ends of the rotary press-fitted steel pipe piles. 2. A plurality of rotary press-fitted steel pipe piles having excavation blades having a diameter larger than the pile diameter at the lower end of the pile are installed by rotary press-fitting into the ground,
A basic structure of a windbreak wall, in which each lower end of a horizontal fall prevention material stretched both on the windward side and on the leeward side of a windbreak wall is connected and fixed to the upper end of the rotary press-fit steel pipe pile. 3. Concrete is placed inside the rotary press-fitted steel pipe pile,
The foundation structure for a windbreak wall according to claim 1 or 2, which is filled with mortar, crushed stone, and sand.