JP3956871B2 - Renewal method and structure of slit sabo dam. - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for renewing a slit sabo embankment in which earth and sand gravel has been captured, and further to a slit sabo dam at that time. Furthermore, the present invention relates to a cross beam structure of a slit sabo dam considering removal.
[0002]
[Prior art]
Most of the conventional sabo dams were impervious sabo dams that crossed rivers. For this reason, depending on the location of the sabo dam, the river is divided so that no sediment is supplied to the downstream area.As a result, the riverbed may be lowered in the downstream area or coastal erosion may occur in the coastal area. there were. In addition, the influence of aquatic organisms such as fish on the living environment is often regarded as a problem.
[0003]
Therefore, in recent years, a sabo dam has been constructed in which a slit portion is provided in the sabo dam and a transmissive slit portion is provided so as to maintain the continuity of the upstream and downstream portions of the dam.
[0004]
However, in a sabo dam with only slits, if a debris flow flows down, the boulder group at the tip of the debris flow can be captured, but the subsequent flow is composed of gravel groups whose gravel diameter is smaller than the tip of the debris flow. On the other hand, it cannot be said that the effect is sufficient, and as disclosed in Patent Document 1, a structure in which a horizontal beam is attached to the slit portion to enhance the soil trapping function has been adopted as a new technique.
[0005]
In addition, there is a sabo levee in which members are combined in a lattice shape as disclosed in Patent Document 2.
[0006]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-50435 [Patent Document 2]
Japanese Patent Laid-Open No. 7-82725 [0007]
[Problems to be solved by the invention]
Since the transmission type sabo dam shown in Patent Document 1 has a horizontal beam attached to the upstream side, the accumulated sediment is limited to the upstream side of the dam, and when the sediment deposited upstream is removed with a heavy machine, Therefore, it is only possible to remove stones from the upstream side of the sabo dam. However, in general, it is often possible to carry heavy equipment to the downstream side of the sabo levee, but it is difficult to carry heavy equipment to the upstream side because it is necessary to provide a new loading road. There are many cases. Therefore, there is a demand for a structure capable of removing debris and gravel, that is, removing stones not only from upstream but also from downstream.
[0008]
In addition, when removing stones with heavy machinery, the horizontal beams often interfere with the work in the stone removal work in the vicinity of the cross beam members, resulting in poor work efficiency and accidentally removing the horizontal beam itself with heavy machinery. It may be damaged. For this reason, if it is possible to remove the cross beam before removing the stone, workability will be greatly improved. However, the earth and sand and gravel collected on the cross beam may be subject to earth pressure, so it can be removed as it is. It is difficult.
[0009]
In addition, the transmission-type sabo dam shown in Patent Document 1 has a horizontal beam attached to the upstream side of the sabo dam. Don't be.
[0010]
However, the upstream side of the sabo dam is extremely dangerous if debris flow or flooding flows from the upstream side during work, but if it is possible to work on the downstream side of the sabo dam, avoid that danger be able to.
[0011]
Here, in the present specification, the debris removal work as described above means that the function of the sabo dam is restored to the old one. This is referred to as “update method”.
[0012]
It is an object of the present invention to provide a slit sabo levee having a structure that is safe when renewing a sabo dam and that can be operated downstream of the sabo dam.
[0013]
Another object of the present invention is to provide a renewal method that can be performed safely and easily on a sabo dam, in which the structure of the transverse beam of the slit sabo dam is particularly designed to be removed.
[0014]
[Means for Solving the Problems]
As a result of various studies on means for solving such a problem, the present inventors attached the cross beam member of the slit sabo dam to the downstream side wall surface of the sabo dam, that is, the both banks on the downstream side, so that the slit portion When stone removal work is necessary after the earth and sand or gravel has been captured, the support device is appropriately brought into contact with the sediment accumulation part in the slit from the downstream side, and the earth pressure is supported by this device. To do. In the meantime, after removing the fixing member of the cross beam member and removing the cross beam member if necessary, the pressure of the support device against the earth pressure is gradually decreased, and the debris from the slit portion is gradually removed to the downstream side as described above. As a result, the present invention has been completed.
[0015]
Such a earth pressure support device can be composed of a tensioned wire and a cross beam as a simple configuration. In other words, wire rods are run along the cross beam member, or when the cross beam member is a tubular body, the wire rod is passed through the inside and at the downstream side wall surface (both sides) of the sabo dam. Attach the wire to the tool and give tension to the wire. As a result, the earth pressure is supported by the action of the supporting device against the earth pressure constituted by the tensioned wire rod and the cross beam member. In the meantime, remove the mounting means such as bolts that fix the cross beam member, and then gradually release the tension applied to the wire, so that the cross beam member can be safely slit even if earth pressure is acting on the cross beam member Enables work to be removed from the section. Thus, after removing the earth pressure support device from the slit portion, the debris and gravel removal work may be performed from the downstream side.
[0016]
Here, the present invention is as follows.
(1) A method for renewing a slit sabo levee having a slit portion in which a cross beam member is installed, and earth and sand gravel captured in the slit portion,
Supporting the earth pressure by the earth and stone in the slit part acting on the cross beam member by the support device;
While the earth pressure in the slit portion is supported by the support device, the mounting means of the cross beam member installed by the mounting means that can be attached to and detached from the downstream side surface of the bank is removed.
Next, a method for updating a slit sabo embankment in which earth and sand gravel is captured, wherein the transverse beam member and the support device are detached from the slit part to enable removal of earth and sand and gravel from the slit part.
[0017]
(2) The support device includes the transverse beam member and a wire material that supports the transverse beam member with its tension, and supports the earth pressure while supporting the transverse beam member with the wire material. The method for renewing a slit sabo dam as described in (1) above, wherein the attaching means is removed, and then the tension of the wire is loosened, and the transverse beam member and the wire are separated from the slit portion.
[0018]
(3) The slit sabo dam according to (1) or (2), wherein the cross beam member is detachably attached to a cross beam mounting member provided on both sides of the downstream side of the slit portion of the sabo dam. Update method.
[0019]
(4) A slit sabo embankment having a slit portion in which one or two or more cross beam members are installed, the cross beam member installed by detachable attachment means on both banks on the downstream side of the slit portion; In the substantially transverse direction of the cross beam member, it is composed of first and second support means for the wire provided on both sides of the downstream side of the slit portion, and third support means for the wire provided on the cross beam member. A slit sabo dam characterized in that the wire, the first, second and third support means and the cross beam member cooperate to constitute a support device for supporting earth pressure in the slit portion.
[0020]
(5) The slit sabo levee according to (4), wherein the cross beam member is detachably attached to a cross beam mounting member provided on both sides of the downstream side of the slit portion of the sabo dam.
[0021]
(6) The transverse beam member is a pipe material, and the third support means is constituted by a hollow portion thereof, or is constituted by a wire metal support provided on the outer surface of the transverse beam member, or the transverse beam The slit sabo levee according to (4) or (5) above, characterized by comprising wire fixing means provided at both ends of the member.
[0022]
(7) The first support means and / or the second support means according to any one of (4) to (6), wherein the first support means and / or the second support means are constituted by anchor fittings provided on both banks on the downstream side of the slit portion. Slit sabo dam.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
As described above, the present invention achieves its intended purpose by using a temporary support device for earth pressure, and there are many forms and mechanisms as such a earth pressure support device. Although considered, the present invention will be described with an embodiment in which an earth pressure support device using a combination of a wire rod and a cross beam member is used as the simplest practical means.
[0024]
According to this aspect of the present invention, as already described, the earth pressure support device is configured by the wire (wire) capable of applying tension to the cross beam member even when the earth pressure is acting on the cross beam member. . In that case, a cross beam member such as a steel pipe is attached not on the upstream side of the sabo dam but on the downstream side wall surface. By doing so, the first and second support means for the wire rod installed on the left and right of the cross beam member, specifically, the wire rod is passed through or fixed to the wire rod support jig, and the wire rod is fixed from both ends or one end to the wire rod. The earth pressure is supported by applying tension from the other end. Such a configuration utilizes the fact that even if the means for attaching the cross beam member is removed, the cross beam member does not suddenly come off and does not jump out of the slit portion.
[0025]
After that, by gradually releasing the tension of the wire from a position away from the embankment if necessary, the transverse beam member is gradually detached from the slit part by the action of earth pressure. Therefore, the cross beam member can be safely detached from the sabo dam, that is, removed. In addition, all these operations can be performed on the downstream side of the safe sabo dam even if there is a debris flow, flood or gravel fall from the upstream.
[0026]
Further, by removing the cross beam member in advance, it is possible to prevent the work efficiency from being lowered due to the cross beam member at the time of stone removal work, and at the same time, it is possible to prevent the cross beam member from being accidentally damaged by a heavy machine or the like. Moreover, the stone removal work can be performed not only from the upstream side but also from the downstream side.
[0027]
In addition, since the positional relationship between the cross beam member, the wire, and the first and second support means of the wire is that the cross beam member needs to be crimped to the sabo dam by applying tension to the wire, when viewed from the front The mounting height of the horizontal beam member and the wire rod support means (eg, fixing jig) should be the same. Further, since the vertical earth pressure is supported by the lateral tension, it is preferable that the wire approaches the downstream wall surface of the sabo dam from the horizontal beam member toward the support means of the wire when viewed from above. In addition, the cross beam member can be crimped to the sabo dam body. For that purpose, it is preferable to provide a certain height from the wall surface of the embankment. Specifically, it is preferable to attach the cross beam member to the wall surface via the cross beam mounting member.
[0028]
【Example】
Embodiments of the present invention will be described in detail with reference to the accompanying drawings.
According to the present invention, the pressure by the earth, that is, the earth pressure is temporarily supported instead of the cross beam member, and the cross beam member is detached during that time. Various devices can be considered as the earth pressure support device at this time, for example, a device in which a wall-like material is brought into contact with the stone and is supported by a hydraulic mechanism from the downstream side of the slit portion between the cross beam members. Alternatively, cover the entire exit of the slit with a net-like member (for example, a wire mesh), apply tension to it to support earth pressure, and press the horizontal beam itself with a heavy machine such as a backhoe to remove the fixing of the horizontal beam. After that, it is possible to move the heavy machinery, but in any case, when releasing the supporting force of earth pressure, it is necessary to release it gradually and to release it remotely. Therefore, in consideration of these, an apparatus using the tension of the wire is the simplest and practical.
[0029]
In the following, as an example of the present invention, a case where a steel pipe is used as the cross beam member and a steel wire (hereinafter simply referred to as “wire”) is used as the wire is shown. The earth pressure “support device” in the illustrated example is composed of a cross beam member, a wire, and appropriate tension applying means (not shown).
[0030]
FIG. 1 is a partially schematic perspective view of a cross beam structure of a slit sabo dam 10 according to the present invention. In the drawing, a sabo dam 10 provided with a slit portion 12 is provided with a transverse beam mounting member 14 in the height direction on both sides of the downstream side of the slit portion 12, that is, on the wall surface 11. The cross beam mounting member 14 is provided with one or two or more cross beam members 16 substantially horizontally at a predetermined interval, and both ends of each cross beam member 16 are bolted to the cross beam mounting member 14 via fixing brackets 20 and can be attached and detached. It has become. The intervals between the cross beam members need not be equal. In the illustrated example, the first and second support means 24 and 26 of the wire 22 are provided in the lateral direction.
[0031]
FIG. 1 is a representative example of a slit sabo dam with a single slit, but the present invention can also be used in a multi-slit structure having two or more slits. Further, in the steel column type slit sabo embankment 40 shown in FIG. 4 to be described later, the present invention can be applied in a mode in which the column members 41, 43 or the cross beam members 16 on the downstream side of the column members 41, 42 or 43, 44 are provided. is there. In addition, the same member is represented with the same code | symbol and the description beyond this is abbreviate | omitted.
[0032]
FIG. 2 is a schematic explanatory view seen from above showing the state of supporting the wire 22 of FIG. 1 more specifically. The principle of the present invention will be described by taking one transverse beam member 16 as an example. The same members as those in FIG. 1 are denoted by the same reference numerals.
[0033]
The reason why the cross beam attaching member 14 is provided is to facilitate removal and to secure a height between the wall surface of the embankment and the cross beam member.
According to the present invention, the first and second support means 24 and 26, which are wire fixing brackets, are provided on the downstream side wall surface 11 of the sabo dam, and the wire 22 is fixed to one of them, in the illustrated example. The wire that has passed through the steel pipe constituting the cross beam member 16 is given tension by appropriate means through the second support means 26 made of the other metal fitting.
[0034]
In another aspect, both the metal fittings are wire support metal fittings, and tension may be applied by pulling from both.
The tension applying means in the present invention is not particularly illustrated, but can be constituted by a heavy machine, a rotating drum, or the like. For example, the wire may be hooked on an appropriate part of the heavy machine and tension may be applied to the wire by moving the heavy machine, or a separate winding drum may be provided, and the wire may be wound around the drum to rotate the drum to apply tension.
[0035]
After applying a predetermined tension to all the cross beam members through the wires, any cross beam members may be removed sequentially while supporting the earth pressure by the tension, or one by one or two or three of the cross beam members. While applying tension through the wire and supporting the earth pressure by the tension, only the transverse beam member at that time may be detached from the slit portion. In this case, this operation is sequentially performed on the other cross beam members, and finally all the cross beam members are detached from the slit portions.
[0036]
According to the present invention, even if the bolt fixing the cross beam member is removed, there is no risk that the cross beam member will be bounced out and removed as long as the earth pressure support device is functioning. There is no danger of coming.
[0037]
While the earth pressure is supported by the earth pressure support device in this way, after removing the bolt from the cross beam member, the tension of the wire is gradually loosened, and the earth and stone can be dropped from the slit part little by little. it can.
[0038]
At this time, the work of loosening the tension of the wire can be performed at a remote position by extending the wire by reversing the drum, moving the heavy machinery, or moving the arm of the backhoe, so that the work can be performed safely.
[0039]
After the wire tension is completely released, the cross beam member is removed from the slit portion. At this time, since there is no obstacle in the slit portion, the work of removing the internal debris and gravel can be performed from the downstream side of the sabo dam with heavy equipment, and the problems so far can be solved at once.
[0040]
In the illustrated embodiment, the transverse beam member needs to be able to easily attach a wire and to be able to stably support the earth pressure even if the fixing bolt is removed only by the tension applied to the wire.
[0041]
The steel pipe is desirable because it only requires the wire to pass inside the steel pipe and does not require any particular processing. However, even if it is not a steel pipe, it is sufficient that the transverse beam member is crimped to the sabo dam with tension applied to the wire, and the fixation of the transverse beam member can be safely removed during that time.
[0042]
For example, as shown in FIG. 3, a guide fitting 34 for attaching the wire 22 may be attached to a cross beam member 30 made of H-shaped steel, and tension may be applied to the wire 22 along this guide fitting 34. In the illustrated example, the cross beam member 30 is directly attached to the wall surface 11 of the sabo dam by anchor bolts 36.
[0043]
In another aspect, a metal fitting for fixing a wire may be provided at both ends of the cross beam member, the wire may be fixed thereto, and tension may be applied to the cross beam member via the wires at both ends. Of course, in this case, tension may be applied from both ends or from one end.
[0044]
FIG. 4 shows an example in which only one side is made of wire. The portion in contact with the cross beam member 30 is composed of a support member 52 made of steel bar or mold steel, one end is fixed to the wall surface by a fixing bracket 54, and the other end is Similarly, it is attached to the wire 22 by a fixing bracket 56. Tension is applied to the support member 52 by pulling the wire 22.
[0045]
The size of the cross beam member is determined by the impact energy of the gravel that flows down during debris flow or flooding and the width of the slit. In the case of steel pipes, a diameter of about 300 to 600 mm is appropriate. In addition, it is not necessary to make all the diameters the same in the height direction.
[0046]
The width of the slit is usually 1 to 2 times the maximum gravel diameter transported by a debris flow or flood that is expected to flow down, and is often less than 3m. Since it is possible, by making the slit width sufficiently large, it is also possible to serve as a loading road for loading heavy machinery to the upstream side.
[0047]
In addition, since the cross beam member is installed on the downstream side, the boulders do not hit the cross beam member when the slit width is set narrow. Therefore, the cross beam member is damaged more than when the cross beam member is installed on the upstream side. Is unlikely.
[0048]
For the joint between the cross beam member and the sabo dam body, if the steel pipe is fixed as it is, the wire will not be crimped sufficiently even if tension is applied. Is desirable. In the embodiment shown in FIG. 1 and FIG. 2, the horizontal beam mounting member 14 is provided as the gap, and the material is an example using H-shaped steel, which is a steel material. It may be wood. Further, even if it is not a continuous body in the vertical direction, it may be provided only in the vicinity of the transverse beam fixing portion as shown in FIG. As described above, the padding, that is, the mounting member also has an effect of securing the height from the seating surface, and there is no limitation as long as it is.
[0049]
About a wire, it is necessary to have the strength which can endure even if it bears the earth pressure which acts on a cross beam member, and elongation is small. This is because if the elongation is large, the wire member may be stretched at the same time that the transverse beam member is removed, and the transverse beam member may move greatly. In this respect, the material used is preferably a steel wire, but can also be a rope, a chemical fiber rope, a chain, or the like.
[0050]
In addition, it can be used as long as it can bear the tension of not only wire rods but also bar steel and mold steel, but in that case, it cannot be wound up like wire rods, so it is not easy to carry on site and when leaving the embankment for remote operation. It must be joined to ensure the length, which is not easy. If there is a risk that the horizontal beam steel pipe will deform greatly when it catches earth and sand and it will be difficult to pass the wire inside the steel pipe, it is also possible to insert a temporary wire for drawing in the steel pipe beforehand. Conceivable.
[0051]
In addition, the wire may be attached only at the time of renewal to remove the stone. Sediment capture function can be maintained.
[0052]
The wire fixing jig only needs to be able to apply tension to the wire, and is preferably a U-bolt, an eyebolt, a pulley, or the like. However, it may not be the same on the right and left of the cross beam member, and one of them can fix the wire completely, and the other can be a jig that can be pulled through the wire so that tension can be applied.
[0053]
In addition, the fixing jig may be installed in advance or may be attached to an existing sabo dam at the time of stone removal (renewal). The operation of applying tension to the wire is most easily performed by heavy machinery.
[0054]
The stone removal work need not be performed in the vicinity of the cross beam member, and by adjusting the length of the wire, it is possible to take a safe distance even if the cross beam member is removed by removing the tension. In addition, even if it is difficult to install a heavy machine for applying tension in the vicinity of the bank, it can be handled by extending the wire length.
[0055]
As a slit sabo levee, as shown in FIG. 5, a steel transmission sabo dam with a structure in which steel pipes 41 to 44 are assembled in a lattice shape inside the slit portion 12 is also seen. However, the present invention is similarly effective. This is because according to the method of the present invention, the cross beam member 16 constituting the steel pipe lattice can be removed little by little. In the present invention, including the case of such a mode, it is said that the transverse beam member is installed “on both banks on the downstream side of the slit portion”.
[0056]
【The invention's effect】
As described above, according to the present invention, when the slit portion of the slit sabo dam is blocked by debris or gravel, the cross beam member can be easily removed, and work from the downstream side of the dam Therefore, it is possible to eliminate the above-mentioned debris and gravel, and it is possible to renew the slit sabo dam, that is, to extend the life by a safe and easy work by heavy machinery, and it is particularly effective in practical use. It is a certain invention.
[Brief description of the drawings]
FIG. 1 is a partially schematic perspective view of a cross beam structure of a slit sabo dam according to the present invention.
FIG. 2 is a schematic explanatory view of a state of attaching a wire having a cross beam structure of a slit sabo dam according to the present invention.
FIG. 3 is a schematic explanatory view showing another aspect of attachment of the wire of the cross beam structure of the slit sabo dam according to the present invention.
FIG. 4 is a schematic explanatory view of another aspect of the earth pressure support device used in the present invention.
FIG. 5 is a horizontal explanatory view of another slit sabo dam to which the present invention is applicable.

Claims (7)

A slit erosion embankment renewal method having a slit portion in which a transverse beam member is installed, and earth and sand gravel captured in the slit portion,
Supporting the earth pressure by the earth and stone in the slit part acting on the cross beam member by the support device;
While the earth pressure in the slit portion is supported by the support device, removing the mounting means of the cross beam member installed by the mounting means removable on the downstream side surface of the bank,
Next, a method for updating a slit sabo dam with seismic gravel captured, wherein the cross beam member and the supporting device are detached from the slit portion to enable removal of debris and gravel from the slit portion. The support device includes the transverse beam member and a wire material that supports the transverse beam member with its tension, and supports the earth pressure while supporting the transverse beam member with the wire material, and means for attaching the transverse beam member therebetween. 2. The slit sabo dam renewal method according to claim 1, wherein the tension of the wire is released and then the transverse beam member and the wire are separated from the slit portion. The method for updating a slit sabo dam according to claim 1 or 2, wherein the cross beam member is detachably attached to a cross beam attachment member provided on both banks on the downstream side of the slit portion of the sabo dam. A slit sabo levee having a slit portion in which one or two or more cross beam members are installed, the cross beam member installed by detachable attachment means on both banks on the downstream side of the slit portion, and the cross beam member The wire comprises first and second support means for the wire provided on each of the two banks on the downstream side of the slit portion in the substantially transverse direction, and third support means for the wire provided on the transverse beam member. A slit sabo levee characterized in that the first, second, third support means and the cross beam member cooperate to support a soil pressure in the slit portion. The slit sabo dam according to claim 4, wherein the cross beam member is detachably attached to a cross beam attachment member provided on both banks on the downstream side of the slit portion of the sabo dam. The transverse beam member is a pipe, and the third support means is constituted by a hollow portion thereof, or is constituted by a wire metal support provided on the outer surface of the transverse beam member, or both ends of the transverse beam member The slit sabo levee according to claim 4 or 5, characterized in that the slit sabo levee is constituted by a wire rod fixing means provided on the wire. The slit sabo levee according to any one of claims 4 to 6, wherein the first support means and / or the second support means are constituted by anchor fittings provided on both banks on the downstream side of the slit.

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