JP7386687B2 - Crown protection work for transparent erosion control dam - Google Patents

Description

The present invention relates to a crown protection work for a transmission-type erosion control dam, and more particularly, to a crown protection construction for reinforcing the crown part of a transmission-type erosion control dam.

Conventionally, a first buffer means is attached to the most upstream column of a permeable sabo dam through an elastic member such as rubber, and the first buffer means is attached to the horizontal beam, connecting beam, and inclined beam at the rear of the permeable sabo dam. A configuration in which a second buffer means is attached is known (see Patent Document 1).

In addition, there is a reinforcement structure that is made of an elastic body and a steel plate embedded in the elastic body, has a U-shaped buffer member in plan view, and covers a part of the upstream side (left side in the figure) of the vertical member of the permeable sabo dam. is known (see Patent Document 2).

Furthermore, a configuration is known in which a rubber formwork is provided on the upper part of an erosion control dam to buffer rocks and the like to protect the structure of the erosion control dam (see Patent Document 3).

Japanese Patent Application Publication No. 2001-234524 Japanese Patent Application Publication No. 2014-185515 JP2009-024377A

Permeable erosion control dams capture debris flows, but after the sand is filled, when the gravel overflows and passes from the crest multiple times (hundreds to thousands of times, etc.), the steel pipes placed near the crest There have been cases of damage and loss due to accumulation of dents. Reinforcing measures against this kind of problem are necessary.

The first buffer means shown in Patent Document 1 and the reinforcing structure shown in Patent Document 2 are buffer structures that are attached to upstream supports of erosion control dams, dams, etc., and are used as buffering and reinforcing means for steel pipes near the top. doesn't work.

The second buffering means shown in Patent Document 2 has the function of absorbing the impact energy of boulders that have passed through the first buffering means or climbed over the dam body, but it is not used as a buffering or reinforcing means for the steel pipe near the top end. doesn't work.

The rubber formwork shown in Patent Document 3 covers a part of the top of the dam, but since it is made of rubber, it may not necessarily have sufficient strength if it is repeatedly hit directly by gravel, and the formwork may not be strong enough. The structure and its mounting structure are not simple configurations.

The present invention aims to solve the above-mentioned conventional problem, and in a permeable sabo dam, after the sand is filled, the flow overflows from the crown and the passing gravel collides with the crown. A transparent sabo dam that absorbs loads and prevents damage or loss of the steel pipes placed at the top, has a simple structure, and can be easily incorporated into existing transparent sabo dams. The challenge is to realize a crown protection work.

In order to solve the above-mentioned problems, the present invention provides a top horizontal crossing member on the upstream side and a top horizontal crossing member on the downstream side, which are provided horizontally in the transverse direction of a river in a permeable erosion control dam. This is a crest protection work that is incorporated into a permeable erosion control dam to reinforce a permeable erosion control dam, and includes multiple vertical protective steel pipes placed horizontally along the flow direction of the river, and multiple vertical protective steel pipes placed horizontally in the transverse direction of the river. a plurality of lateral coupling members that intersect with the directional protection steel pipe and couple the plurality of longitudinal protection steel pipes to each other; an engagement member fixed to the front end of the longitudinal protection steel pipe and extending downward; and a downstream of the lower end of the engagement member. A plurality of longitudinal protection steel pipes are provided with a slip prevention member that is fixed to the side end surface and suppresses the lateral movement of the top protection work, and the front and rear sides of each of the plurality of longitudinal protection steel pipes are provided with cushioning rubber for mounting. , is placed on the top horizontal cross member on the upstream side and the top horizontal cross member on the downstream side of the top end of the permeable sabo dam, and the engaging member A crown protection work is provided, characterized in that it is configured to be engaged with a top horizontal cross member on the upstream side of a type erosion control dam.

It is preferable that the mounting cushioning rubber is provided via a cushioning rubber attachment web fixed to the longitudinal protection steel pipe.

The anti-slip member is fixed to the engagement member so that when the crown protection works moves in the transverse direction of the river, it will come into contact with the upstream vertical column forming the permeable erosion control dam. something that is

According to the crown protection work of a permeable erosion control dam according to the present invention, the following effects are produced.
(1) The cushioning rubber can reduce the gravel collision load and also reduce the cumulative deformation of the steel pipe due to multiple debris collisions, so the deformation of the permeable sabo dam body almost never occurs. do not have.

(2) It can be installed on top of the top of the transparent sabo dam body (existing or new) by simply inserting it from upstream. Since it is placed on the surface, construction precision is not required. Therefore, the crest protection work can be easily built into the main body of a permeable sabo dam without the need for scaffolding, and is highly economical. Therefore, it can be easily installed especially in the body of a permeable erosion control dam installed in a mountainous area or the like.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram illustrating an example of a permeable erosion control dam body incorporating a crown protection work according to the present invention, in which (a) is a side view, (b) is a plan view, and (c) is a view from the upstream side. FIG. It is a figure explaining the Example of the crown protection work based on this invention, (a) is a top view, (b) is a BB sectional view of (a), (c) is (a) FIG. It is a perspective view of the crown protection work of the said Example, (a) is a figure seen from diagonally above upstream, (b) is a figure seen diagonally from below downstream. A state in which the crown protection work of the above embodiment is mounted and incorporated on the crown part of the permeable sabo dam body will be explained, (a) is a side view, and (b) is a B of (a). -B sectional view (vertical sectional view seen from the downstream side). It is a figure which shows the permeable type sabo dam in which the crown protection work of the said Example was mounted and incorporated in the crown part of the permeable type sabo dam main body, (a) is a side view, (b) is a downstream side FIG. It is a figure which shows the transparent type sabo dam in which the crown protection work of the said Example was mounted and incorporated in the crown part of the transparent type sabo dam main body, (a) is the whole top view, (b) It is an enlarged view of the main part of (a). It is a perspective view seen from the upstream side showing the principal part of the penetration type sabo dam in which the crown protection work of the above-mentioned example is placed and incorporated in the crown part of the penetration type sabo dam main body.

EMBODIMENT OF THE INVENTION The form for implementing the crown protection work based on this invention is demonstrated below with reference to drawings based on an Example.

(Example)
Embodiments of the crown protection work according to the present invention will be described with reference to FIGS. 1 to 7. In this specification, when a permeable sabo dam is viewed from the upstream side, left and right are referred to as left and right, the width direction of the river is referred to as the transverse direction (left-right direction), or the horizontal direction, and the upstream and downstream directions of the river are also referred to as the vertical direction.

The permeable erosion control dam body incorporating the crown protection work according to the present invention may have a well-known structure, an example of which is shown in FIG. The permeable sabo dam main body 1 of this embodiment includes an upstream permeable wall 3 and a downstream permeable wall 4, which are installed on a concrete foundation 2 at intervals on the upstream and downstream sides. 5 is a concrete side wall.

The upstream permeable wall 3 and the downstream permeable wall 4 are each formed into a lattice structure (see FIG. 1(c)) by combining vertical columns 7 and horizontal cross members 8 made of steel pipes in a lattice shape, and They are connected by a horizontal connecting member 9 extending in the upstream and downstream directions. The downstream permeable wall 4 is supported by a diagonal support member 10 or the like from the downstream side.

In this specification, the uppermost horizontal cross member 8 of the horizontal cross members 8 forming the upstream permeable wall 3 is referred to as the top horizontal cross member 15 on the upstream side, and the horizontal cross member forming the downstream permeable wall 3 is referred to as the top horizontal cross member 15. 8, the uppermost horizontal cross member 8 is referred to as the top horizontal cross member 16 on the downstream side.

As shown in FIGS. 1(a) to (c), the permeable sabo dam main body 1 has a top horizontal cross member 15 on the upstream side and a top horizontal cross member 16 on the downstream side with an interval between them at the top end 14. It is set aside.

The permeable erosion control dam main body 1 to which the crown protection work 20 according to the present invention can be applied needs to have a structure in which such an upstream top horizontal crossing member 15 and a downstream top horizontal crossing member 16 are provided. There is.

In short, the permeable sabo dam body is provided with an upstream top horizontal cross member and a downstream top horizontal cross member on which the crown protection work 20 can be placed on the upstream and downstream sides of the top end. In this case, the crown protection work 20 can be applied to a permeable sabo dam body that does not necessarily have the structure of this embodiment.

Top protection:
The configuration of the crown protection work 20 will be explained with reference to FIGS. 2 to 4 and the like. As shown in FIGS. 2 and 3, the crown protection work 20 includes a plurality of longitudinal protection steel pipes that extend horizontally along the flow direction (upstream and downstream direction) of the river, and these plurality of longitudinal protection steel pipes. A plurality of horizontal coupling members are provided which intersect and couple the plurality of longitudinal protection steel pipes in parallel with each other.

In this embodiment, as shown in FIGS. 2(a), (b), and 3, as a plurality of longitudinal protection steel pipes, left and right longitudinal protection steel pipes 21 located on the left and right when viewed from the upstream side, An intermediate longitudinal protection steel pipe 22 located between the longitudinal protection steel pipes 21 of They are coupled to each other by a directional coupling member 23.

In this embodiment, as shown in FIGS. 2 and 3, the horizontal connecting member 23 uses a steel pipe, but the horizontal connecting member 23 connects the vertical protective steel pipes 21 and 22 so that they do not shift from each other. Therefore, it is not necessarily necessary to use a steel pipe, and other members such as shaped steel may be used.

An engaging member 26 extending downward is provided at the upstream end of all or some of the plurality of longitudinal protection steel pipes 21 and 22. A slip prevention member 28 is provided on the downstream end surface of the engagement member 26.

In this embodiment, an H-shaped steel is used as the engagement member 26, and its upper end portions are fixed to the upstream ends of the left and right vertical protection steel pipes 21 by welding or the like, and are provided so as to extend downward. Note that the engaging member 26 does not necessarily have to be an H-shaped steel.

A contact buffer rubber 27 is attached to a part of the downstream end surface of the engaging member 26. In this way, the crown protection work 20 can be incorporated into the permeable sabo dam main body 1, which will be described later, without having the abutment buffer rubber 27 attached to a part of the downstream end surface of the engagement member 26. At this time, a separately prepared contact buffer rubber 27 may be inserted into the portion where the top protection work 20 contacts the top horizontal cross member 15.

Further, on the downstream end surface of the lower end of the engagement member 26, a slip prevention member 28 made of H-shaped steel is fixed by welding or the like below the portion where the abutting buffer rubber 27 is attached. In this embodiment, the anti-slip member 28 is made of H-shaped steel, but it does not necessarily have to be made of H-shaped steel.

The anti-slip member 28 used has a smaller cross-sectional dimension (dimension of a vertical cross-section in the longitudinal direction) than the engaging member 26 . As mentioned above, the anti-slip member 28 is fixed to each of the engagement members 26 fixed to the upstream ends of the left and right vertical protection steel pipes 21, and the position where the anti-slip member 28 is fixed is such that it can function as a anti-slip member. shall be.

That is, as will be described later, as shown in FIGS. 4 to 7, when the crown protection work 20 is assembled in the crown part 14 of the permeable erosion control dam main body 1, as shown in FIGS. 4(b) and 5(b) As shown in FIG. 2, the left and right anti-slip members 28 are fixed so as to face each other and to be located close to the insides of the vertical pillars 7 of the corresponding left and right upstream transmission walls 3.

Here, "proximity" in the present invention means that when the crown protection work 20 is about to move (lateral shift) in the transverse direction of the river, the shift preventing member 28 This is the distance at which the top protection work 20 is restrained (restrained) from moving in the transverse direction.

As shown in FIGS. 2 and 3, buffer rubber mounting webs 30 are fixed to the lower surfaces of the front and rear ends of the left and right and intermediate longitudinal protection steel pipes 21 and 22 (a plurality of longitudinal protection steel pipes). There is.

Although various configurations of the buffer rubber mounting web 30 can be considered, in this embodiment, the buffer rubber mounting web 30 is arranged with respect to the upstream and downstream directions of the river, as shown in FIGS. 2(b) and 3(b). The orthogonal vertical cross section is ⊥-shaped, and includes a vertical plate 31 and a horizontal plate 32.

A mounting buffer rubber 33 is attached to the lower surface of the horizontal plate 32 of the buffer rubber attachment web 30. The mounting cushioning rubber 33 will be described later, but as shown in FIG. It is a cushioning rubber that cushions the collision load in the event of a collision.

The mounting cushioning rubber 33 has a thickness of about 5 to 10 cm, and its lower surface is the main body of the permeable sabo dam to be mounted, as shown in FIGS. 2(c), 3(a), and (b). A curved surface is formed (marked with R) along the upper surfaces of the top horizontal cross member 15 on the upstream side and the top horizontal cross member 16 on the downstream side in the top end 14 of No. 1.

The mounting buffer rubber 33 is made of porous material that has been made into chips and hardened, so that it is more easily deformed than solid rubber, and is pushed by the weight of the vertical protection steel pipes 21 and 22, causing the permeable erosion control dam body 1 to deform. It fits into the top horizontal cross member 15 on the upstream side and the top horizontal cross member 16 on the downstream side.

In this embodiment, the web 30 for attaching buffer rubber for mounting is provided on the longitudinal protection steel pipes 21 and 22, and the buffer rubber 33 for mounting is provided via this web 30 for attaching buffer rubber for mounting. However, it is not necessarily necessary to provide the web 30 for attaching the mounting buffer rubber.

That is, when installing the crown protection work 20 into the transmission-type sabo dam body 1, etc., a separately prepared mounting buffer rubber is placed between the vertical protection steel pipes 21, 22 and the upstream side of the transmission-type sabo dam body 1. It may also be configured to be inserted between the top horizontal cross members 15 of the.

Installation of crown protection work:
When constructing the crown protection work 20 to be incorporated into the transmission-type sabo dam body 1, the crown protection work 20 is installed on the crown part 14 of the transmission-type sabo dam body 1 using heavy equipment such as a crane (not shown). It is lifted upwards on the upstream side and brought close to the top end 14 of the transmission-type sabo dam body 1 so as to be inserted from the upstream side.

As shown in FIG. 4, the mounting buffer rubber 33 provided at the front and rear ends of the left and right vertical protection steel pipes 21 and the middle vertical protection steel pipe 22, respectively, is attached to the permeable erosion control dam body. It is placed on the top horizontal cross member 15 on the upstream side and the top horizontal cross member 16 on the downstream side at the top end 14 of No. 1.

At this time, the engaging member 26 abuts and engages with the top horizontal cross member 15 of the permeable sabo dam main body 1 from the upstream side via the abutting buffer rubber 27, and furthermore, the engaging member 26 contacts and engages with the top horizontal cross member 15 of the permeable sabo dam body 1 from the upstream side via the abutting buffer rubber 27. The left and right anti-slip members 28 provided on the side end faces are positioned close to the inside of the upstream vertical column member 7 so as to face each other.

By incorporating the plurality of crown protection works 20 into the transparent sabo dam body 1 as described above, as shown in FIGS. 4 to 7, a plurality of The structure is a permeable sabo dam 37 in which a crown protection work 20 is arranged.

In addition, if the longitudinal protection steel pipes 21 and 22 are not equipped with the buffer rubber mounting web 30, as described above, when installing the crown protection work 20 into the permeable erosion control dam main body 1, a separately prepared mounting The cushioning rubber for the installation may be inserted between the top protection work 20 and the top horizontal cross member 15 on the upstream side.

In addition, if the abutment cushioning rubber 27 is not attached to the downstream end surface of the engaging member 26, a separately prepared rubber rubber 27 is provided between the engaging member 26 and the top horizontal cross member 15 on the upstream side during installation. Just insert a cushioning rubber for contact.

As described above, the crown protection work 20 can be installed on top of the top end 14 of the transparent Sabo dam body 1 (existing or newly constructed) by simply inserting it from the upstream side. Since it is placed via the mounting buffer rubber 33, construction accuracy is not required.

Therefore, the crown protection work 20 can be easily built into the permeable erosion control dam body 1 without building scaffolding, and is highly economical. Therefore, it can be easily installed even in the main body 1 of a permeable sabo dam installed especially in a mountainous area.

(effect)
The operation of the crown protection structure 20 having the above-described configuration will be explained below in connection with the permeable erosion control dam 37 shown in FIGS. 4 to 7, which includes the crown protection structure 20. The permeable sabo dam 37 captures the debris flow flowing from the upstream of the river, and when the river becomes full of sand, the wave height h of the debris flow becomes higher on the upstream side of the permeable sabo dam 37, as shown in FIG. 4(a). .

Then, the gravel 36 in the debris flow flows down toward the top end 14 of the permeable erosion control dam 37. However, in the transparent type erosion control dam 37, since the crown protection work 20 is provided, some of the gravel 36 collides with the longitudinal protection steel pipes 21 and 22 of the crown protection work 20, but the collision load ( The collision energy) is absorbed by the mounting cushioning rubber 33 via the cushioning rubber attachment web 30, producing a cushioning effect.

Further, if the colliding gravel 36 is relatively large, the vertical protection steel pipes 21 and 22 of the crown protection work 20 may be dented. However, due to such concave deformation, the collision load caused by the gravel 36 is absorbed and a buffering effect is produced.

In this way, the collision load of the gravel 36 can be reduced by the mounting cushioning rubber 33, and moreover, it can be absorbed by the cumulative deformation of the denting of the longitudinal protection steel pipes 21, 22 caused by multiple collisions of the gravel 36. Therefore, the collision load of the gravel 36 has almost no effect on the permeable sabo dam body 1, and deformation, damage, etc. hardly occur.

Above, the form for implementing the crown protection work according to the present invention has been explained based on the examples, but the present invention is not limited to such examples, and the embodiments described in the claims It goes without saying that there are various embodiments within the scope of technical matters.

Since the crest protection work according to the present invention has the above-mentioned configuration, it can be applied to various permeable erosion control dams, but it is particularly difficult to construct due to topographical and environmental considerations, and is also applicable to relatively many It can also be applied to permeable erosion control dams installed in rivers such as mountainous areas where debris flows containing gravel flow down.

1 Transparent type sabo dam body
2 Concrete foundation
3 Upstream transparent wall
4 Downstream side permeable wall 5 Concrete side wall
7 Vertical column material
8 Horizontal transverse member
9 Horizontal binding material
10 Diagonal support material
14 Top part
15 Upstream top horizontal cross member
16 Downstream top horizontal cross member
20 Crown protection work
21 Left and right vertical protection steel pipes
22 Intermediate longitudinal protection steel pipe
23 Lateral coupling member
26 Engagement member
27 Buffer rubber for contact
28 Slip prevention member
30 Buffer rubber mounting web
31 Vertical plate
32 Horizontal board
33 Buffer rubber for mounting
36 Gravel
37 Permeable erosion control dam

Claims (3)

It is installed on the top of a permeable sabo dam, which has a top horizontal cross member on the upstream side and a top horizontal cross member on the downstream side, which are provided horizontally in the transverse direction of the river, to reinforce the permeable sabo dam. It is a crown protection work,
A plurality of longitudinal protection steel pipes arranged horizontally along the flow direction of the river, and a plurality of longitudinal protection steel pipes arranged horizontally in the transverse direction of the river and intersecting with each other to connect the plurality of longitudinal protection steel pipes to each other. A horizontal coupling member, an engagement member fixed to the front end of the longitudinal protection steel pipe and extending downward, and a gap fixed to the downstream end surface of the lower end of the engagement member to suppress lateral movement of the crown protection work. A stop member;
The front and rear sides of each of the plurality of longitudinal protection steel pipes are connected to the top horizontal cross member on the upstream side and the top horizontal cross member on the downstream side of the top end of the transmission type erosion control dam, respectively, through the mounting buffer rubber. placed on top;
A crown protection work characterized in that the engaging member is configured to be engaged from the upstream side with the top horizontal cross member on the upstream side of the permeable erosion control dam via a contact buffer rubber. 2. The crown protection work according to claim 1, wherein the installed buffer rubber is provided via a buffer rubber attachment web fixed to the longitudinal protection steel pipe. The anti -slip member is fixed to the engagement member so that when the crown protection works moves in the transverse direction of the river, it comes into contact with an upstream vertical pillar that constitutes a permeable erosion control dam. The crown protection work according to claim 1 or 2, characterized in that:

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