JPS61277710A - Scouring-preventing member and manufacture thereof - Google Patents

Abstract

PURPOSE:To prevent wear and damage of an anchor bolt, by a method wherein recessed parts are formed in a souring-preventing member, a through-hole, extended between the bottom surface of the recessed part and the back of the scouring member, is provided, and a notch is formed in the side wall part of the recessed part. CONSTITUTION:Plural columnar recessed parts 2 are formed in a surface part 1a, and a through-hole in a circle in cross section, extended between a bottom surface 2a of the recessed part 2 and a back 1b. A notch 5 is formed in the side wall of the recessed part 2 to form a scouring-preventing member 1. The top part 9a of an anchor bolt 9, buried in a concrete block 8 on a river bed, is inserted into a through-hole 3 from the back surface 1b side of the member 1, and the member 1 is placed on the block 8. A wash 10 and a nut 11 are threadedly joined with the top part 9a to secure the member 1 to the block 8, and thereafter, the interior of the recessed part 2 is filled with a filling protection material 13.

Description

Detailed Description of the Invention (Industrial Application Field) The present application relates to a scour prevention member and a method for manufacturing the same, for example, a member installed on a river bed on the upstream or downstream side of a river weir or dam,
The present invention relates to a scouring prevention member that prevents scouring of riverbeds caused by debris flows during floods, and a method for manufacturing the same.

(Prior Art) Conventional scouring prevention members include, for example, those shown in FIGS. 8 and 9. FIG. 8 is an overall schematic diagram showing how the scouring prevention member is used on a riverbed. be.

In FIG. 8, 31 is a scour prevention member, and the scour prevention member 31 is a top end 33a on the upstream side of the fixed weir 33 of the river 32.
It is installed so as to cover the upper part of the concrete block 34 from the apron part 33b on the downstream side.

Anchor bolts 35 are provided on the concrete block 34. A recess 37 is provided in the front surface 31a of the scour prevention member 31, and a through hole 38 passes through from the bottom surface 37a of the recess 37 to the back surface 31b of the scour prevention member 31.

The anchor bolt 35 penetrates from the back surface 31b side to the inside of the recess 37, and a washer and a nut 39 are attached to the top part 35a of the anchor bolt 35 to fix the scour prevention member 31 to the concrete block 34.

When river 32 floods due to landslides and landslides, river JI+
Debris flow 41 flows down into 32, and a large number of boulders 42 pass over scour prevention member 31 of fixed weir 33.

In the conventional scour prevention member 31, as shown in FIG. 9, in order to prevent the top portion 35a of the anchor bolt 35 from being worn away by boulders 42 or earth and sand, the concave portion 37 is filled with liquid natural vulcanized rubber or the like for protection. It is filled with material 45.

(Problems to be Solved by the Invention) However, these filling protection materials 45 are repeatedly impacted by boulders 42 in flowing water due to several floods, and the recesses 37
There is a problem in that it falls off and falls off.

Therefore, the first invention of the present application is capable of preventing the filling protection member in the recess from coming off and falling off even if boulders in a debris flow caused by a flood collide with the recess of the scour prevention member, thereby preventing wear and tear on the top of the anchor bolt. In addition to providing a scour prevention member that can prevent damage, the second invention of the present application provides a method for manufacturing a scour prevention member that is easy to manufacture, takes a short time, and has productivity that does not require tools such as jigs. The purpose is to provide a manufacturing method with high cost and low cost.

(Means for solving the problem) A scour prevention member according to the first invention of the present application is a scour prevention member that prevents scour caused by running water, and includes a recess and a through hole that penetrates from the bottom surface to the back surface of the recess. , and a notch formed in the side wall of the recess. Second part of the application
A method for manufacturing a scour prevention member according to the invention includes an upper mold;
The lower mold has a cavity and is combined with the upper mold. The lower mold has a substrate, a lower protrusion integrally formed on the substrate, and a lower protrusion having a cross-sectional area smaller than that of the lower protrusion. a first step of preparing a mold having a plurality of convex portions, a second step of installing a lower mold with the convex portions upward; and a second step of installing a lower mold with the convex portions upward; A third step of attaching the protruding elastic member, a fourth step of filling the cavity of the lower mold with a scour prevention member made of unvulcanized rubber, and a fifth step of combining the upper mold with the lower mold.
a sixth step of vulcanizing the scour prevention member by heating and pressurizing the upper mold and the lower mold from the outside, and removing the upper mold and simultaneously taking out the scour prevention member and the elastic member from the cavity of the lower mold. The method is characterized by comprising a seventh step, and an eighth step of taking out the elastic member from the scour prevention member and forming a notch in the scour prevention member.

(Function) The scour prevention member is installed to cover the concrete block, and a nut is attached to the top of the anchor bolt located within the recess of the scour prevention member. The recess is filled with a filling protection material, and the top of the anchor bolt and the nut are buried therein.

During a flood, a debris flow flows in a river, and a large number of boulders pass through a fixed weir and repeatedly collide with the recesses of the scour prevention member, repeatedly impacting the protective material filled in the recesses.

However, since a notch is formed in the side wall of the recess of the scour prevention member according to the first invention of the present application to prevent the filling protection material from falling out, the filling protection material falls out and falls off. The anchor bolt head will not wear out or break.

In addition, in the conventional method of manufacturing a scour prevention member, the protruding member does not correspond to the notch of the scour prevention member attached to the side wall of the lower protruding portion of the lower mold, and the protrusion member is a scour prevention member made of unvulcanized rubber. After vulcanization, the scour prevention member and the protruding member are removed from the lower mold cavity. Since the protruding member protrudes from the side wall portion, a large force is required to take it out, and furthermore, a jig is required for taking it out. However, according to the manufacturing method according to the second invention of the present application, the protruding member is made of an elastic member, and the elastic member expands and contracts.
Since they are deformed, the scour prevention member and the elastic member can be taken out from the lower mold very easily and simultaneously in a short time with little force without the need for a jig. Further, the elastic member can be taken out from the scour prevention member and used again for manufacturing the scour prevention member, which reduces costs.

(Example) Hereinafter, an example of the scour prevention member according to the first invention of the present application will be described based on the drawings.

1 and 2 are diagrams showing a first embodiment of a scour prevention member according to the first invention of the present application.

First, the configuration will be explained.

In FIG. 1, ■ is a scouring prevention member, and the scouring prevention member 1 has a plurality of cylindrical recesses 2 provided at predetermined positions on the surface 1a and the bottom surface 2a of the recess 2. back side 1
It has a through hole 3 with a circular cross section that penetrates up to b.

5 is a notch, and the notch 5 is located in the lower side wall portion 2 of the recess 2.
An annular hole 5a having a diameter larger than the cylindrical diameter D2 of the recess 2, protruding into the side wall 2b, and having a circular cross section.
is formed. Reference numeral 6 denotes a reinforcing material (campus in this embodiment), and the reinforcing material 6 is provided near the back surface 1b in parallel with the back surface 1b, and reinforces the strength of the scour prevention member 1.

When the scouring prevention member 1 is installed on the riverbed of a fixed weir or dam, the scouring prevention member 1 is placed on a concrete block 8 in the riverbed and buried in the concrete block 8, as shown in FIG. The top portion 9a of the anchor bolt 9 passes through the through hole 3 from the back surface 1a side of the scour prevention member 1 and reaches the inside of the recess 2. A washer 1 is attached to the top 9a inside the recess 2.
0 and a nut 11 are screwed together, and the scour prevention member 1 is fixed to the concrete block 8. Reference numeral 13 denotes a filling protection material, which is filled in the recess 2, embedding the top 9a of the anchor bolt 9, the washer 10, and the napht 11, and filling the notch 5.

Next, the effect will be explained.

The boulders or earth and sand in the debris flow collide with the filling protection material 13 in the recess 2 of the scour prevention member 1, and repeatedly impact the filling protection material 13. Although the filling protection material 13 tries to escape from the recess 2 and fall off, the filling protection material 13 fills the notch 5 of the side wall portion 2b of the recess 2 of the scour prevention member 1 according to the first invention of the present application, and the filling Since the protective material 13 is prevented from coming off, the filled protective material 13 will not come off and fall off. Therefore, the top portion 9a of the anchor bolt 9 will not be worn or damaged.

FIG. 3 is a diagram showing a second embodiment of the scour prevention member according to the first invention of the present application. In the second embodiment, the notch 16 of the concave portion of the scour prevention member 15 is an annular hole 1 having a substantially triangular cross section, instead of the annular hole 5a having a substantially circular cross section in the first embodiment.
6a, the configuration, operation, and effect are the same, so the same reference numerals are given and the explanation will be omitted.

FIG. 4 is a diagram showing a third embodiment of the scour prevention member according to the first invention of the present application. In the third embodiment, the notch 19 of the recess of the scour prevention member 18 extends from the top end 2c of the recess 2 to the bottom surface 2a of the recess 2, instead of the annular hole 5a having a substantially circular cross section in the first embodiment. The structure, operation, and effect are the same except that the notch 19 is provided to gradually increase the cross-sectional area S2, so the same reference numerals are given and the explanation will be omitted.

In the above-mentioned embodiment, the cross-sectional shape of the recessed portion is circular, but the first invention of the present application is not limited to this embodiment. good.

Further, in the above embodiment, the shape of the notch is a continuous annular hole having a substantially circular cross section projecting into the side wall of the recess, but in the first invention of the present application, this embodiment However, the notch may protrude from a part of the side wall, as long as the filling protection material does not come off or fall off.

Next, a method for manufacturing a scour prevention member according to the second invention of the present application will be explained based on the drawings.

FIGS. 5 to 7 are diagrams for explaining the steps of the method for manufacturing a scour prevention member according to the second invention of the present application.

First, the equipment prepared in the first step will be described.

FIG. 5 is a partial sectional view showing the configuration of the device. In FIG. 5, reference numeral 21 denotes a mold for manufacturing the scour prevention member, and the mold 21 is composed of an upper mold 22 and a lower mold 23. The upper mold 22 is made of a flat iron plate, and the lower mold 23 has a cavity 23a made of iron (the figure shows the cavity 24 filled with unvulcanized rubber, which will be described later). Combine. Lower mold 23
is based on the cross-sectional area of the flat plate-shaped substrate 24 facing the upper mold 22, the lower protrusion bone 25 integrally formed on the substrate 24 and extending in the direction of the upper mold 22, and the lower protrusion bone 25. It also has a small cross-sectional area and includes a plurality of convex portions 27 including an upper protruding portion 26 that is in contact with the upper mold 22 . The side wall portion 25a of the lower protrusion bone 25 is provided with a valley portion 29 (the elastic member 28 is shown attached in the figure) to which an elastic member 28, which will be described later, is attached over the entire circumference.

In the second step, the lower mold 23 is placed on a predetermined table (not shown) 4 with the convex portion 27 facing upward.

In the third step, an annular elastic member 28 (polyurethane rubber in this embodiment) having a circular cross section is attached to the lower protruding rib 25 of the lower mold 23 so as to protrude outward into the valley 29 of the side wall 25a. In the fourth step, in advance, unvulcanized rubber 30
The cavity 23a of the lower mold 23 is filled with a scour prevention member 30, which is formed by forming a reinforcing material 30b (campus in this embodiment) into a layer and having cylindrical holes 30c at predetermined locations. In the fifth step, the upper mold 22 is replaced with the lower mold 2.
Combine from above 3. In the sixth step, the upper mold 22 and the lower mold 23 are heated and pressurized from the outside, and the scour prevention member 30 is filled into the cavity 23a and vulcanized, as shown in FIG. In the seventh step, the upper mold 22 is removed, and the vulcanized scour prevention member 30 and elastic member 28 are simultaneously taken out from the cavity 23a of the lower mold 23, as shown in FIG. In the eighth step, the elastic member 28 is taken out from inside the recess 30d corresponding to the convex part 27 in the scour prevention member 30, and as shown in FIG. A protruding annular notch 30f with a circular cross section is formed.

Next, the effect will be explained.

In the method of manufacturing a scour prevention member, the lower mold 23
Since the elastic member 28 attached to the side wall 25a of the lower protruding bone 25 projects inside the scour prevention member, when the vulcanized scour prevention member 30 is taken out from the cavity 23a of the lower mold 23, Although it requires extremely large force, the second part of the present application
According to the method for manufacturing a scour prevention member according to the invention, since the elastic member 28 expands, contracts, and deforms, the elastic member 28 can be manufactured together with the scour prevention member 30 very easily, in a short time, and with little effort. It can be taken out. Moreover, it can be easily taken out from the scour prevention member 30, and the working time can be shortened. Furthermore, the elastic member 28 can be used again, resulting in a significant cost reduction.

(Effects of the Invention) As explained above, according to the first invention of the present application, even if boulders or earth and sand in a debris flow caused by a flood collide with the recess of the scour prevention member, the protective material filled in the recess may fall out or It can be prevented from falling off, and therefore the top of the anchor bolt can be prevented from wearing and breaking.

Further, according to the second invention of the present application, even if the scour prevention member has a protruding notch on the side wall of the recess, the scour prevention member can be removed from the cavity of the lower mold very easily and in a short period of time after vulcanization. It can be taken out manually. Moreover, the elastic member forming the notch can also be easily taken out from the recess of the scour prevention member and can be used again. therefore,
It can shorten work time and reduce labor, greatly improve productivity, and significantly reduce costs.

[Brief explanation of drawings]

1 and 2 are diagrams showing a first embodiment of the scour prevention member according to the first invention of the present application, FIG. 1 is an enlarged sectional view of the main part thereof, and FIG. 2 is a view of the member installed on a riverbed. FIG. 3 is an enlarged cross-sectional view of main parts. FIG. 3 and FIG. 4 are enlarged sectional views of main parts showing a second embodiment and a third embodiment of the scour prevention member according to the first invention of the present application, respectively. 5 to 7 are diagrams for explaining the steps of the method for manufacturing a scour prevention member according to the second invention of the present application, and FIG. 5 is a diagram for explaining the first to sixth steps,
FIG. 6 is a diagram for explaining the seventh step, and FIG. 7 is a diagram for explaining the eighth step. FIGS. 8 and 9 are views showing a conventional scour prevention member, with FIG. 8 being an overall schematic diagram showing its usage, and FIG. 9 being an enlarged sectional view of its main parts. 1.15.18...Scouring prevention member, ■b...
...Back surface, 2.30d...Concave portion, 2a...Bottom surface, 2b...Side wall portion, 3...Through hole, 5.16.19 .30f...Notch, 21...
... Mold, 22 ... Upper mold, 23 ... Lower mold, 23a ... Cavity, 24 ... Substrate, 25 ... ...lower protruding bone, 26...upper protruding bone, 27...convex portion, 28...elastic member, 30... scour prevention member .

Claims (1)

[Claims] 1) A scour prevention member that prevents scour caused by running water,
A scouring prevention member comprising: a recess; a through hole penetrating from the bottom of the recess to the rear surface; and a notch formed in a side wall of the recess. (2) Consisting of an upper mold and a lower mold that has a cavity and is combined with the upper mold, the lower mold has a substrate, a lower protrusion integrally formed on the substrate, and a cross-sectional area of the lower protrusion. a first step of preparing a mold with a plurality of protrusions having an upper protrusion with a small cross-sectional area; a second step of installing a lower mold with the protrusions facing upward; and a second step of installing a lower mold with the protrusions facing upward; A third step of attaching an elastic member protruding from the side wall of the part, a fourth step of filling the cavity of the lower mold with a scour prevention member made of unvulcanized rubber, and a fifth step of combining the upper mold with the lower mold. a sixth step in which the upper mold and the lower mold are heated and pressurized from the outside to vulcanize the scour prevention member; and a sixth step in which the upper mold is removed and the scour prevention member and the elastic member are simultaneously taken out from the cavity of the lower mold. A method for manufacturing a scour prevention member, which comprises a seventh step and an eighth step of taking out an elastic member from the scour prevention member and forming a notch in the scour prevention member.