JP2002275864A - Surface sealed wall fill dam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface sealed wall fill dam eliminating a fear of cracking in a sealed wall even when subjected to great water pressure by a water storage pond. SOLUTION: The surface sealed wall fill dam comprises the sealed wall (a concrete slab 3) installed on the surface on the upstream side of a dam body 1, the sealed wall (the concrete slab 3) having at least a lateral cross section forming continuous arches.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface impervious wall fill dam in which a water impervious wall made of concrete or asphalt concrete is installed on an upstream surface of a bank body.

[0002]

2. Description of the Related Art As a conventional surface damping wall fill dam of this type, an upstream surface of a levee constructed of a material mainly composed of a natural material such as a highly permeable rock is shielded by an artificial material such as concrete. The thing which installs a water wall is known.

According to the surface impervious wall fill dam, no pore water pressure is generated in the embankment, and the water pressure in the reservoir works in a direction in which the effective stress of the embankment increases. There is an advantage that can be relatively steep.

[0004]

However, in this type of surface impervious wall fill dam, the material of the impervious wall is too large in resistance to deformation as compared with the embankment, so that the dam is not suitable for the water pressure. In the case where a large tensile stress occurs in the impermeable wall, there is a disadvantage that cracks cannot be avoided.

Accordingly, an object of the present invention is to provide a surface impervious wall fill dam in which cracks do not occur in the impervious wall even when receiving a large water pressure from a reservoir.

[0006]

That is, a surface impervious wall fill dam according to a first aspect of the present invention is a surface impervious wall fill dam having a water impervious wall installed on an upstream surface of a bank body. The wall is characterized in that at least the transverse cross section forms a continuous arch.

According to the surface impervious wall fill dam of the first invention, since the impervious wall at least has a continuous cross section in the form of a continuous arch, the impervious wall receives a large water pressure from the reservoir. Also, the large water pressure can be transmitted by the in-plane stress, and no large tensile stress occurs on the impermeable wall. Therefore, according to this, it is possible to avoid a situation that causes the occurrence of cracks in the impermeable wall.

[0008] In such technical means, the impermeable wall is installed on the upstream surface of the embankment, and at least the cross section in the lateral direction forms a continuous arch. Any structure may be used as long as a material having a small water permeability is used so as not to cause the generation of water. Therefore, for example, not only the cross section in the horizontal direction may form a continuous arch but also the cross section in the vertical direction may have a structure similar to a so-called shell structure forming a continuous arch. .

However, from the viewpoint of more reliably avoiding the occurrence of cracks in the impermeable wall, a portion of the impermeable wall that serves as a fulcrum of a continuous arch is vertically disposed on the embankment. It is preferable that a filling material is filled between the embankment body and the impermeable wall while being supported by the underground beam.

On the other hand, a surface impervious wall fill dam according to the second invention is a surface impervious wall fill dam having a water impervious wall installed on an upstream surface of a bank body, wherein the impervious wall is uniform. It is characterized by forming a flat slab. here,
The “uniform flat slab” means not only a flat slab having a uniform thickness dimension and a construction method, but also a uniform flat slab in terms of concrete composition, reinforcing bar amount, and the like. According to the surface impervious wall fill dam according to the second invention, the impervious wall is formed as a uniform flat slab, so even when receiving a large water pressure from the reservoir, the impervious wall is partially formed on the impervious wall. No large tensile stress occurs. Therefore, according to this, it is possible to avoid a situation that causes the occurrence of cracks in the impermeable wall.

[0011]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a schematic configuration of a surface impervious wall fill dam according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a detailed configuration of the surface impervious wall fill dam.

In this embodiment, the surface impervious wall fill dam has a schematic structure as shown in FIG.
A water impervious wall 3 is installed on the upstream surface of the slab. As shown in FIG. 2, the embankment body 1, the underground beam 2, a concrete slab 3 as a water impervious wall, And a filling material 4. Hereinafter, each component will be described in detail.

(1) Embankment 1 The embankment 1 is constructed of a material mainly composed of a natural material such as a highly permeable rock.

FIG. 1 shows the upstream surface of such a bank 1
As shown in FIG. 2, a concrete slab 3 made of concrete, which is an artificial material, is installed. Further, at the center of the concrete slab 3, although not shown, a reinforcing bar for preventing cracking by resisting a binding force generated in the concrete slab 3 due to drying shrinkage or the like is arranged in a lattice shape.

The gradient on the upstream side of the embankment 1 is shown in FIG.
As shown in the figure, it is relatively steep, but this is because the concrete slab 3 is installed on the upstream surface,
Not only does pore water pressure not occur in the embankment 1,
This is because the water pressure in the reservoir also works in the direction in which the effective stress of the bank body 1 increases.

(2) Underground Beam 2 As shown in FIG. 2, the underground beam 2 is located near the upstream surface of the embankment body 1 in the vertical direction at an interval corresponding to a portion of the concrete slab 3 which becomes a fulcrum of an arch. It is arranged in.

The underground beam 2 supports the portion of the concrete slab 3 serving as the fulcrum of the continuous arch with a sufficiently strong structure, so that the force transmitted from the concrete slab 3 can be reliably ensured. It plays a role of transmitting to the embankment body 1.

With the underground beam 2, a more stable supporting state of the concrete slab 3 can be obtained, and the occurrence of cracks in the concrete slab 3 can be more reliably avoided.

(3) Concrete Slab 3 As shown in FIG. 2, the concrete slab 3 has a shape such that the cross section in the lateral direction forms a continuous arch.

The concrete slab 3 bears a large water pressure (see the arrow shown in FIG. 2) from the reservoir with in-plane stress and transmits the same to the embankment 1.

In other words, the surface impervious wall fill dam according to the present embodiment receives a large water pressure from the reservoir. According to such a concrete slab 3, a large water pressure can be borne and transmitted with in-plane stress. Therefore, a large tensile stress does not occur in the concrete slab 3, and therefore, no crack is generated in the impermeable wall.

Since the concrete slab 3 is supported by the above-mentioned strong underground beam 2, it has a structure that is sufficiently considered against settlement and earthquake.

In the present embodiment, only the cross section in the lateral direction has a shape forming a continuous arch, but the present invention is not limited to this. For example, it is also possible to use a combination of a plurality of so-called shell structures that form a continuous cross section in the vertical direction as well as in the horizontal direction.

(4) Filling Material 4 Filling material 4 is filled between the embankment 1 and the concrete slab 3, as shown in FIG. 2, and in the present embodiment, the embankment 1 An aggregate having a greater ability to resist deformation than the material used for the above is used.

Since the concrete slab 3 is always faced and supported by the filling material 4, the in-plane stress generated in the concrete slab 3 can be further reduced. It is possible to more reliably avoid the occurrence of cracks.

Therefore, according to the surface damping wall fill dam according to the present embodiment, since the concrete slab 3 having a continuous cross section forming a continuous arch, the large water pressure received from the reservoir is subjected to the in-plane stress. And the concrete slab 3 is no longer subjected to a large tensile stress.

That is, according to the surface impervious wall fill dam, no crack is generated in the concrete slab 3 and it is not necessary to repair it by resin or injection. In the case of a surface impervious wall fill dam in which a water impervious wall is installed on the upstream surface of the embankment, another embodiment in which the impermeable wall forms a uniform flat slab is adopted. In this case, it is possible to enjoy substantially the same effects as those of the surface impermeable wall fill dam according to the present embodiment. That is, according to the surface impervious wall fill dam according to such another embodiment, the impervious wall is formed as a uniform flat slab, so even when receiving a large water pressure from the reservoir. In addition, a large tensile stress does not occur partially on the impermeable wall, and it is possible to avoid a situation that causes the occurrence of cracks on the impermeable wall.

[0029]

According to the present invention, there is provided a surface damping wall fill dam which does not crack even when receiving a large water pressure from the reservoir because of the above construction. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a surface impermeable wall fill dam according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a detailed configuration of a surface impervious wall fill dam according to one embodiment of the present invention.

[Explanation of symbols]

 1 ... embankment 2 ... underground beam 3 ... concrete slab (water barrier) 4 ... filling material

Claims (3)

[Claims] 1. A surface impervious wall fill dam comprising an impervious wall installed on an upstream surface of an embankment body, wherein the impervious wall forms an arch whose cross section at least in a lateral direction is continuous. Characterized by the surface impermeable wall fill dam. 2. A portion of the impermeable wall serving as a fulcrum of a continuous arch is supported by an underground beam vertically arranged on the embankment, and between the embankment and the impermeable wall. 2. The surface impervious wall fill dam according to claim 1, wherein the filling material is filled with a filling material. 3. A surface impervious wall fill dam having an impervious wall installed on an upstream surface of an embankment body, wherein the impervious wall forms a uniform flat slab. Impermeable wall fill dam.