JP5956789B2 - How to drain the dam - Google Patents

Description

  The present invention relates to a drainage method for a dam lake in which water is dammed up by accumulated earth and sand.

  When a landslide caused by an earthquake or heavy rain occurs, a dammed lake may be formed if the flowing sediment accumulates and the river water is blocked. If the water level of the dam lake rises due to further heavy rain or river increase, the portion that dams the water (hereinafter referred to as the dam portion of the dam lake) may break down, causing serious damage to the downstream side. Therefore, it is required to quickly drain the water from the dam and remove the earth and sand from the levee to quickly eliminate the dam.

  By the way, the drainage work when a water disaster occurs is generally performed using a pump. For example, Patent Document 1 discloses that when a water disaster occurs, a drainage pump vehicle loaded with a submersible pump is made to reach a drainage site, and the submersible pump is thrown into the water of the drainage site to perform drainage.

JP 2000-161282 A

  When draining from a dam lake using a pump, a large-scale pump capable of discharging a large flow rate is required to quickly lower the level of the dam lake. However, the above-mentioned dam lakes often occur in mountainous areas where landslides are likely to occur, and even when the drainage pump is carried by vehicle to the site, roads along the way are often blocked by landslides. Therefore, it is difficult to load a large drain pump on a vehicle as described in Patent Document 1 and transport it to the site (dam lake). Moreover, there are few flat places suitable for installation of the above-mentioned large drainage pump at the site of landslide. Therefore, it is necessary to start by securing a wide and flat place where large-scale drainage pumps can be installed by removing debris and leveling, etc. It will take time.

  The objective of this invention is providing the drainage method of a dam lake which can drain | emit the water of a dam lake easily and rapidly, without using a drain pump.

Means for Solving the Problems and Effects of the Invention

A drainage method for a dam lake according to a first aspect of the present invention is a drainage method for a dam lake in which water is blocked by accumulated earth and sand, and the dam lake and the water of the dam lake are blocked. A hose laying process for laying a drainage hose across a drainage position that is on the opposite side of the dam and sandwiching the levee, and discharging the air in the drainage hose However, in the hose laying step, one end of the drainage hose is turned over and fixed at the drainage position in the hose laying step. While inverting the front and back of the hose by applying fluid pressure to the inside, the tip of the reversal is advanced by the fluid pressure, and the drainage hose is laid from the drainage position over the levee to the dammed lake that It is an butterfly.

In the present invention, a drainage hose is laid across the dam lake and the drainage position on the opposite side of the dam lake over the embankment, and further filled with water while discharging the air in the drainage hose, Fill the hose with water. Here, since the drainage position is lower than the dam lake, the so-called siphon principle allows the water filled in the section from the top of the dam lake to the drainage position to flow toward the drainage position by gravity. Thus, negative pressure is generated in the drainage hose, and water in the dam is sucked up in the section from the top of the levee to the dam. As a result, the water in the dam lake continues to flow to the drainage position over the top of the embankment that is higher than the dam lake. According to the present invention, since the water in the dam lake can be drained to the opposite drainage position beyond the embankment without using a drainage pump, drainage work becomes easy, Drainage can be started quickly without taking much time for preparatory work before drainage.
In the present invention, the drainage hose is laid by inverting the front and back of the drainage hose while continuously advancing the tip of the flipping hose. Therefore, the drainage hose can be easily laid along the slope of the bank. Also, the drainage hose can be laid so as to get over the ground even when the ground condition is bad or there is an obstacle. Furthermore, the laying direction of the drainage hose can be easily changed simply by changing the direction of the tip of the drainage hose.

The drainage method for a dam lake according to a second invention is the drainage method of the dam lake in the first invention, wherein the end of the drain hose on the dam lake side is submerged in the dam lake in the filling step. By sucking and discharging the air in the drain hose from the drainage position side, the water in the dammed lake is drawn into the drain hose.

  In the present invention, after the drainage hose is laid from the dam lake to the drainage position, the air in the drainage hose is sucked and discharged from the drainage position side. The hose can be filled with water. Further, the drainage hose can be filled with water by the work on the drainage position side. Therefore, the water filling operation into the drain hose is facilitated.

According to a third aspect of the present invention, there is provided a drainage method for a dam lake, wherein, in the first invention, the drain hose is sealed with an end on the dam lake side and an end on the drain position before the filling step. The drainage hose is provided with a water injection part and an exhaust part, and in the filling step, water is injected from the water injection part into the drainage hose by a water injection pump from the exhaust part into the drainage hose. The drainage hose is filled with water, and after the filling step, the end of the drainage hose on the side of the dam and the end of the drainage position side are opened. To do.

  In the present invention, after sealing both the end of the drainage hose on the side of the dammed lake and the end of the drainage position side, while injecting water from the water injection part into the drainage hose, Drain the air and fill the drain hose with water. After that, when the end of the drainage hose on the side of the dam lake and the end on the side of the drainage position are opened, the water in the dam lake flows out to the drainage position over the bank.

In the present invention, it is necessary to inject water into the drainage hose with a water injection pump, but this water injection pump only needs to be capable of injecting the integral water of the drainage hose into the drainage hose within a certain time. Compared to a drainage pump for continuously draining the water of a dammed lake, a small one is sufficient. Therefore, it is easy to carry-in work such that it can be carried into the site by human power, and the installation place on the site is small.
A drainage method for a dam lake according to a fourth aspect of the present invention is the drainage hose according to the third aspect, wherein a watertight bag is attached to an end of the drainage hose on the drainage position side so as to cover the open end. A pipe for discharging water in the bag body to the outside is attached between the outer surface of the end portion of the drainage hose and the bag body.
By attaching a water-tight bag to the end of the drainage hose on the drainage position side so as to cover the open end, it is possible to prevent air from entering from this end and stopping drainage. In addition, by attaching a pipe between the end of the drain hose and the bag body, a drainage path for the water discharged from the drain hose to the inside of the bag body is secured to prevent the air from entering from the open end. Drainage can be continued while preventing with the bag.
A drainage method for a dam lake according to a fifth aspect of the invention is a drainage method for a dam lake in which water is dammed up by accumulated earth and sand, and the dam lake and the water in the dam lake are dammed up. A hose laying process for laying a drainage hose across a drainage position that is on the opposite side of the dam and sandwiching the levee, and discharging the air in the drainage hose However, the filling step of filling the drainage hose with water, and before the filling step, the end of the drainage hose on the dam lake side and the end on the drainage position side, respectively The drainage hose is provided with a water injection part and an exhaust part. In the filling step, water is injected from the water injection part into the drainage hose by a water injection pump, and the drainage hose is supplied from the exhaust part. The air inside is discharged and the drainage hose After the filling step, the drain hose side end and the drainage position side end of the drainage hose are opened, and the drainage hose end of the drainage hose is opened to the drainage side. A watertight bag is attached so as to cover the pipe, and a pipe for discharging water in the bag to the outside is attached between the outer surface of the end of the drainage hose and the bag. Is.
In the present invention, after sealing both the end of the drainage hose on the side of the dammed lake and the end of the drainage position side, while injecting water from the water injection part into the drainage hose, Drain the air and fill the drain hose with water. After that, when the end of the drainage hose on the side of the dam lake and the end on the side of the drainage position are opened, the water in the dam lake flows out to the drainage position over the bank.
In the present invention, it is necessary to inject water into the drainage hose with a water injection pump, but this water injection pump only needs to be capable of injecting the integral water of the drainage hose into the drainage hose within a certain time. Compared to a drainage pump for continuously draining the water of a dammed lake, a small one is sufficient. Therefore, it is easy to carry-in work such that it can be carried into the site by human power, and the installation place on the site is small.
In addition, by attaching a watertight bag body to the end of the drainage hose on the drainage position side so as to cover the open end, it is possible to prevent air from entering from this end and stopping the drainage. In addition, by attaching a pipe between the end of the drain hose and the bag body, a drainage path for the water discharged from the drain hose to the inside of the bag body is secured to prevent the air from entering from the open end. Drainage can be continued while preventing with the bag.
A drainage method for a dam lake according to a sixth aspect of the invention is characterized in that, in the fourth or fifth aspect of the invention, one end of the pipe projects beyond the open end of the drainage hose in the bag body. It is.
Inside the bag, one end of the pipe projecting beyond the open end of the drainage hose
Since it is kept away from the open end, drainage is prevented from being blocked by the bag.
It is.

A drainage method for a dam lake according to a seventh aspect of the present invention is the drainage hose according to any one of the third to sixth aspects , wherein the water injection section and the exhaust section are provided in a portion of the drainage hose positioned at the top of the levee section. It is characterized by being.

  Usually, the top of the embankment that is blocking the water of the dam lake is at the highest position in the drainage hose laying path. Therefore, if a water injection part and an exhaust part are provided at the top part of the drainage hose, water head pressure does not act on the water injection part, so water can be injected into the hose with a small water injection pump. The air can be easily discharged from the drain hose.

According to an eighth aspect of the present invention, there is provided a drainage method for the dam lake in the seventh aspect , wherein in the hose laying step, a first section from the top to the dam lake and a second from the top to the drainage position.
The drainage hoses are individually laid in the section, and the two drainage hoses respectively laid in the first section and the second section are connected to a connector installed on the top of the levee section. The two drain hoses are connected via a connecting tool, and the water injection part and the exhaust part are provided in the connecting tool.

  In the present invention, the drainage hose is separately laid in the first section from the top of the levee to the dam and the second section from the top of the levee to the drainage position, Connect both drain hoses. Here, since the water injection part and the exhaust part are provided in the connector installed at the top part, it is not necessary to provide the water injection part or the exhaust part in the drainage hose itself.

According to a ninth aspect of the present invention, there is provided a drainage method for a dam lake in the eighth aspect , wherein the connector has a curved leg portion.

  According to the present invention, even when the state of the ground at the top of the levee is poor, such as when rocks and irregularities are scattered, the legs of the coupler are not easily caught by rocks and irregularities, Easy to install and move.

According to a tenth aspect of the present invention, there is provided a drainage method for a dam lake according to any one of the third to ninth aspects, wherein the drain hose has an end portion on the dam lake side and an end portion on the drainage position side. By inserting the plug member and the second plug member, respectively, the end on the dam lake side and the end on the drainage position side are sealed.

  Thus, the end portion can be reliably sealed by inserting the plug member into the end portion of the drainage hose.

  The drainage method for a dam lake according to an eleventh invention is characterized in that, in the tenth invention, at least one of the first plug member and the second plug member includes an expansion body that expands by air injection. To do.

  According to the present invention, the end portion of the drainage hose can be easily sealed and opened by injecting and discharging air to the expansion body.

  The drainage method for a dam lake according to a twelfth aspect of the present invention is the drainage hose according to the tenth or eleventh aspect, wherein the plug is attached to at least one of the end of the drain hose on the dam lake side and the end on the drainage position side. A drop prevention member for preventing the member from falling off from the drainage hose is attached.

  When the drainage hose is filled with water, there is a possibility that the first stopper member or the second stopper member may come off due to the water head pressure at the end of the drainage hose at a low position. In the present invention, the stopper member is prevented from falling out of the drain hose by attaching the drop prevention member to the end of the drain hose.

  The drainage method for a dam lake according to a thirteenth aspect of the present invention is the drainage hose according to any one of the first to twelfth aspects, wherein the drainage hose has a hose body made of a tubular fabric, and the inner surface and the outer surface of the hose body. Both are covered with a synthetic resin coating.

  Even if the inner surface of the tubular fabric is covered with a synthetic resin coating, the watertightness of the drainage hose is secured. However, when the pressure in the drainage hose becomes a negative pressure, there is a possibility that the coating is peeled off from the tubular fabric due to the atmospheric pressure acting on the coating on the inner surface through the texture of the tubular fabric. In the present invention, the outer surface of the tubular woven fabric is also covered with the synthetic resin coating, thereby preventing the above-described peeling of the coating on the inner surface. In addition, since the outer surface of the tubular fabric is covered with the coating, the tubular fabric is prevented from being damaged during laying.

It is a figure which shows the state in the middle of laying of the drainage hose based on 1st Embodiment of this invention. It is a figure which shows the state which laying of the drainage hose was completed. It is a figure explaining the filling process of the water into a drainage hose. It is a figure explaining the drainage process from a dam lake. It is sectional drawing of a reversing machine. It is an enlarged view of the edge part by the side of the dam lake of a drainage hose. It is a figure explaining the preparatory process before the drainage from a dam lake based on 2nd Embodiment of this invention. It is a figure explaining the drainage process from a dam lake. It is a perspective view of a coupling tool. It is a figure explaining the drainage process from a dam lake concerning the change form of 2nd Embodiment. It is an enlarged view of the edge part of the drainage hose shown by FIG. It is an enlarged view of the edge part of the drainage hose of another modification. It is an enlarged view of the edge part of the drainage hose of another modification. It is a figure explaining the preparatory process before drainage concerning another modification.

(First embodiment)
Next, a first embodiment of the present invention will be described. FIG. 1 is a diagram showing a state in the middle of laying a drainage hose according to the first embodiment, FIG. 2 is a diagram showing a state in which the drainage hose has been laid, and FIG. 3 is filling water into the drainage hose. The figure explaining a process and FIG. 4 are figures explaining the drainage process from a dam lake.

  As shown in FIGS. 1 to 4, earth and sand that have flowed out due to landslides and the like are accumulated to form a levee portion 1, and river water is dammed by the levee portion 1, thereby forming a dam lake 2. In this embodiment, first, as shown in FIGS. 1 and 2, drainage on the opposite side of the dam lake 2 and the dam lake 2 (right side in the figure: hereinafter also referred to as the skirt side) across the embankment portion 1. A drainage hose 5 is laid over the position 3 (hose laying step). In addition, as can be seen from FIG. 1, the drainage position 3 on the skirt side is in a low land that is considerably lower than the water surface of the dam lake 2. Next, as shown in FIG. 3, the inside of the drainage hose is filled with water (filling process), and the so-called siphon principle is used to drain the water in the dam lake 2 into the drainage hose 5 as shown in FIG. 4. To drain the drainage basin 8 installed at the drainage position 3 (drainage process).

(Hose laying process)
First, the drainage hose 5 is laid across the dam lake 2 and the drainage position 3 on the hem side and beyond the top 1 a of the levee 1. In the present invention, the method of laying the drainage hose 5 is not particularly limited. However, in the first embodiment, as shown in FIGS. The drainage hose 5 is laid by moving the inverted tip portion 5 a to the dam lake 2 along the slope of the levee 1 while inverting.

The drain hose 5 is not particularly limited as long as it has water tightness, but in the following, a synthetic resin (for example, polyvinyl chloride) is provided on both the inner surface and the outer surface of a jacket (hose body) made of a tubular woven fabric. A case where a shape-retaining hose having a coating of a hard thermoplastic resin such as the above is used will be described as an example. The diameter of the drainage hose 5 is not particularly limited. However, if the diameter is small, the amount of drainage decreases. On the other hand, if the diameter is large, the weight increases and the laying operation becomes difficult. From these viewpoints, a drainage hose having a diameter of about 100 to 200 mm can be preferably used. Moreover, as a jacket, the thing of the following specifications can be used, for example.
(Diameter: 200mm)
Warp: Polyester yarn 1100T / 4 × 2 × 312 Weft: Polyester yarn 1100T / 5 × 45P

  When laying the drainage hose as described above, first, a reversing machine 6 for inverting the front and back of the drainage hose 5 is installed in a relatively flat place of the drainage position 3 on the skirt side. FIG. 5 is a cross-sectional view of the reversing machine.

  As shown in FIG. 5, the reversing machine 6 includes a pressure vessel 10, a reel 11, a heater 12, and the like. Pressurized air is supplied to the pressure vessel 10 from an air supply source (not shown) connected to the air supply unit 10a. A drain hose 5 is wound on the reel 11 in a state of being flattened. Then, the drainage hose 5 wound around the reel 11 is pulled out to the delivery port 10 b of the pressure vessel 10 through the heater 12 installed between the two pairs of guide rollers 13 and 14. Further, one end portion of the drainage hose 5 drawn out is fixed to the vicinity of the delivery port 10b of the pressure vessel 10 by the fixing tool 15 in an inverted state.

  When pressurized air is supplied into the pressure vessel 10, air pressure (fluid pressure) acts on the inside of the end portion of the drainage hose 5 turned upside down. Further, the drainage hose 5 drawn out from the reel 11 is heated by the heater 12 to a temperature equal to or higher than the softening temperature of the film made of a thermoplastic resin such as polyvinyl chloride (for example, 80 ° C.). Thereby, the flexibility of the drainage hose 5 is increased, and the front and back of the drainage hose 5 are reversed while being pulled out of the reel 11 by the pressure of the pressurized air. At this time, the portion where the drainage hose 5 is reversed (the tip portion 5a of the reverse) advances forward. Accordingly, by inverting the front and back of the drainage hose 55 and advancing the tip 5a of the reverse, the drainage hose 5 is laid along the slope of the levee 1 to the dam lake 2 as shown in FIGS. can do.

  As described above, the drainage hose 5 is laid using the continuous advancement of the tip portion 5a of the drainage hose 5 so that the drainage hose 5 can be used even in an environment where the work of the slope of the levee portion 1 is difficult. Can be laid easily. In addition, there are many obstacles such as fallen trees and rocks on the slope of the levee 1, and driftwood may exist around the dam 2. However, in the laying by reversal described above, the drainage hose 5 can be quickly laid over the obstacle, and the laying work is facilitated without the need for prior removal of the obstacle. Further, during the reversal, the non-reversed portion 5b (see FIG. 5) of the drainage hose 5 is drawn out inside the reversed portion, and no friction is generated between the drainage hose 5 and the drainage hose 5 is hardly damaged. . In addition, when there are obstacles that cannot be overcome, such as trees and large rocks, on the slope of the levee part 1, it is necessary to change the direction in which the drainage hose 5 is laid. The laying direction can be easily changed simply by changing the direction of the tip portion 5a.

  FIG. 6 is an enlarged view of the end of the drainage hose on the dam lake side. The end 30a of the drainage hose 5 on the dam lake 2 side (the end opposite to the end 30b on the drainage position 3 side fixed to the reversing machine 6) is the part that is finally inverted. The end 30a is joined by adhesive, sewing, etc. before the reversal laying, and the open end is sealed so that the pressure of pressurized air acts on the reversal tip portion 5a until the reversal of 5 is completely completed. Has been. However, when the end 30a of the drainage hose 5 is finally reversed, the joint portion is cleaved by the pressure of the pressurized air, and the open end is opened. In other words, the bonding strength of the open end of the end portion 30a is such that it can be cleaved by the pressure of pressurized air used for reversal.

(Filling process)
When the drainage hose 5 has been laid to the dam lake 2, the drainage hose 5 is then filled with water. First, as shown in FIG. 3, a suction source 7 such as a vacuum pump is connected to the end 30 b of the drain hose 5. The end 30b of the drainage hose 5 and the suction source 7 may be connected by connecting the suction source 7 to the reversing machine 6 while the reversing machine 6 is attached to the end 30b. Alternatively, the end 30b may be connected to the suction source 7 after the reversing machine 6 is removed from the end 30b. Then, the suction source 7 is driven in a state where the other end portion of the drain hose 5 is submerged in the dam lake 2, and the air in the drain hose 5 is sucked and discharged from the drain position 2 side. Then, since the pressure in the drainage hose 5 is reduced to a negative pressure, the water in the dam lake 2 is drawn into the drainage hose 5 and the air in the drainage hose 5 is replaced with water. Thus, the water in the dam lake 2 can be drawn into the drain hose 5 and the drain hose 5 can be filled with water simply by sucking and discharging the air in the drain hose 5 from the drainage position 3 side. Further, all of the operations such as connection of the suction source 7 to the drainage hose 5 and start of suction by the suction source 7 are performed on the drainage position 2 side. Therefore, the water filling operation to the drain hose 5 is facilitated.

(Drainage process)
When it is confirmed that water has flowed out to the drainage position 3 side, it is assumed that the air in the drainage hose 5 is almost exhausted, and the end 30b of the drainage hose 5 is disconnected from the suction source 7 and installed at the drainage position 3. Put it in a drainage basin 8.

  Once the drainage hose 5 is filled with water, even after the suction source 7 is disconnected, the water in the dam 2 is located at the top of the levee portion 1 at a higher position by the so-called siphon principle. It will continue to flow over the drainage position 3 lower than the dam lake 2 over 1a.

  As shown in FIG. 4, the end 30 b of the drainage hose 5 installed in the drainage basin 8 at the drainage position 3 is lower than the end 30 a of the drainage hose 5 submerged in the dam lake 2. And in the section from the drainage position 3 to the top part 1a, the water in the drainage hose 5 flows toward the drainage basin 8 by gravity, but this reduces the pressure of the part installed in the top part 1a of the levee part 1. Negative pressure. On the other hand, due to this negative pressure, in the section from the top 1a to the dam lake 2, the water of the dam 2 is sucked up toward the top 1a. By performing this action continuously, the water in the dam lake 2 continues to flow to the drainage position beyond the top 1a of the bank 1. In addition, once the flow of water from the dam lake 2 to the drainage position 3 occurs, air enters from the end portions 30a and 30b of the drainage hose 5 and the watertight state inside the drainage hose 5 is eliminated. Unless the water level of the dam 2 is lowered and the height relationship with the drainage position 3 is reversed, the above water flow continues.

  Further, during the drainage, as shown in FIG. 4, the end 30b of the drainage hose 5 on the drainage position 3 side is submerged in the drainage basin 8, and the drainage hose 5 extends from the end 30b. Air is hard to enter inside. Therefore, the watertight state in the drainage hose 5 is easily maintained, and continuous drainage is possible.

  In addition, as mentioned above, a negative pressure is generated inside the drain hose 5 at a position higher than the dam lake 2 (particularly, at the top 1a of the bank 1). Therefore, it is preferable that the drainage hose 5 is configured to maintain watertightness even when used in a negative pressure environment. For example, in the case of the above-described hose mainly composed of a jacket made of a tubular woven fabric, the water tightness of the drainage hose 5 is ensured even if the inner surface of the laid tubular woven fabric is covered with a synthetic resin coating. . However, when the pressure in the drainage hose 5 becomes a negative pressure, there is a possibility that the coating is peeled off from the tubular fabric due to the atmospheric pressure acting on the coating on the inner surface side through the texture of the tubular fabric. . Therefore, in order to prevent the peeling of the coating on the inner surface side, it is desirable that not only the inner surface of the tubular woven fabric but also the outer surface is covered with a synthetic resin coating. Moreover, in this structure, there exists an effect that the outer surface of a cylindrical fabric is protected by a film and damage is prevented. In addition, it is described in Unexamined-Japanese-Patent No. 50-31417 that the hose which has the above structure can be used in a negative pressure environment.

  In the first embodiment described above, the drainage hose 5 is laid over the dam lake 2 and the drainage position 3 on the hem side beyond the top 1a of the levee 1 and then the drainage hose 5 is filled with water. To do. Then, according to the so-called siphon principle, the water in the dam lake 2 flows out to the drainage position 3 on the opposite side over the embankment 1 on the way, and drainage continues from the dam lake 2. Thereby, the water in the dam lake 2 can be drained to the drainage position 3 without using a drain pump. Therefore, the drainage work becomes easy, and drainage can be started promptly without taking much time for the preparatory work before drainage.

  Next, a modified form of the first embodiment will be described. However, components having the same configuration as in the first embodiment are denoted by the same reference numerals and description thereof is omitted as appropriate.

1] When laying the drainage hose 5 by reversal, it is possible to use a fluid such as water in addition to pressurized air. However, in this case, the weight of the draining hose 5 during reversal is increased, and the head pressure acts on the hem side when laying above the slope of the levee 1, which is disadvantageous. Therefore, from these viewpoints, it is preferable to reverse the drainage hose 5 using pressurized air as in the first embodiment.

2] In the first embodiment, the sealed end 30a of the drainage hose 5 is opened by the pressure of pressurized air used for reversal, but it is difficult to open by the pressure of pressurized air. Alternatively, the operator may perform an operation of opening the end 30a on the dam lake 2 side.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In addition, about the thing which has the structure similar to the said 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted suitably. FIG. 7 is a diagram illustrating a preparatory step (hose laying step, filling step) before draining from the dam lake 2 according to the second embodiment. FIG. 8 is a diagram for explaining a drainage process from the dam lake 2.

  This second embodiment differs from the first embodiment described above in the following points. First, as shown in FIGS. 7 and 8, in the hose laying process, instead of laying a single drainage hose 5 from the dam lake 2 to the drainage position 3 on the hem side, from the top 1 a of the levee 1. Drain hoses 5A and 5B are individually laid in a section 17 (first section) to the dam lake 2 and a section 18 (second section) from the top 1a of the levee 1 to the drainage position 3. Further, in the filling step, the ends 30a and 30b of the drain hoses 5A and 5B are sealed, respectively, and then water is filled by injecting water into the drain hoses 5A and 5B. Hereinafter, the hose laying step and the filling step will be described focusing on differences from the first embodiment.

(Hose laying process)
The drain hoses 5A and 5B in the first section 17 and the second section 18 may be laid by inverting the front and back of the drain hoses 5A and 5B, respectively, as in the first embodiment. Alternatively, both the drainage hoses 5A and 5B are transported to the top 1a of the bank 1 and the rolled hose is rolled from the top 1a to the dam 2 and the drainage position 3 respectively. The hoses 5A and 5B may be laid.

  Moreover, as shown in FIG. 7, the connecting tool 9 which connects drainage hoses 5A and 5B is installed in the top part 1a of the bank 1. FIG. 9 is a perspective view of the connector 9. The connector 9 includes two cylinders 20 and 21 and leg portions 22 provided at the lower portions of the two cylinders 20 and 21.

  As shown in FIG. 9, the two cylinders 20 and 21 are joined to each other at their ends, and are bent upward as a whole. Then, by connecting the ends of drain hoses 5A and 5B laid in the first section 17 and the second section 18 to these two cylinders 20 and 21, respectively, and fixing them with a band 24, two drains Hose 5A, 5B is connected via the connector 9 (cylinder 20, 21). The two cylinders 20 and 21 are provided with a water injection part 25 and an exhaust part 26, respectively. The water injection part 25 and the exhaust part 26 are for filling the interior of the drainage hoses 5A and 5B connected by the connector 9 with water in a filling process described later.

  The leg 22 is a member having a curved grounding portion 22a, that is, a so-called sled shape. Thus, even if it is a case where the state of the ground of the top part 1a of the levee part 1 has a bad state where rocks and unevenness | corrugation are scattered because the connection tool 9 has the curved leg part 22, a leg part 22 is less likely to get caught by rocks, unevenness, and the like, and the connecting device 9 can be easily installed. In addition, it becomes easy to change the position by moving the connector 9 a little while the drain hose 5 is already connected and a large load is applied to the leg portion 22.

  Note that a fitting 23 to which a rope or the like can be connected at the time of installation is attached to a connecting portion between the two cylinders 20 and 21. For example, the coupling 9 is suspended by a rope coupled to a helicopter. Can be transported to the top 1a. Alternatively, the connecting tool 9 may be pulled up from the hem side to the top 1a along the slope of the levee portion 1 by passing the rope to the dam lake 2 side and pulling the rope from the dam lake 2 side. The connector 9 may be made of metal from the viewpoint of securing a certain level of strength, but it is made of resin for weight reduction in consideration of transport to the top 1a. You can also

(Filling process)
When the drainage hose 5 has been laid, as shown in FIG. 7, the drainage hose 5B laid in the second section 18 and the end 30a of the drainage hose 5A laid in the first section 17 on the dam lake 2 side. The end portions 30b on the drainage position 3 side are respectively sealed.

  Here, the end portions 30a and 30b are securely sealed by inserting plug members (first plug member and second plug member) into the end portions 30a and 30b of the drainage hose 5, respectively. The first plug member and the second plug member are not particularly limited in configuration, but here, as the first plug member and the second plug member, an airtight bag body that expands by injecting air. An air packer (expanded body) made of In this air packer, the end portions 30a and 30b can be easily sealed and opened by air injection and discharge, and the operation is easy.

  As shown in FIG. 7, the air packer 31 as the first plug member is inserted into the end 30a of the drain hose 5A in the first section 17, while the end 30b of the drain hose 5B in the second section 18 is The air packer 32 as the second plug member is inserted. The two air packers 31 and 32 are connected to the air pumps 33 and 34 through hoses, respectively. Valves 35 and 36 are attached between the air packers 31 and 32 and the air pumps 33 and 34. Then, by supplying air from the air pumps 33 and 34 to the two air packers 31 and 32, the air packers 31 and 32 are expanded to seal the ends 30a and 30b, respectively. Further, by closing the valves 35 and 36 after the air packers 31 and 32 are expanded, the expanded state (sealed state of the end portions 30a and 30b) is maintained. In addition, the end 30a of the drain hose 5A is submerged in the dam lake 2, and the end 30b of the drain hose 5B is placed in the drain 8 installed in the drainage position 3.

  Next, water is filled in the drainage hoses 5A and 5B in which the end portions 30a and 30b are sealed. As described above, a water injection part 25 and an exhaust part 26 are provided in the connector 9 that connects the two drainage hoses 5A and 5B. A water injection pump 37 is connected to the water injection portion 25 of the connector 9 via a hose, and a valve 38 is attached in the middle thereof. An air vent hose 39 is connected to the exhaust part 26, and a valve 40 is attached to the air vent hose 39. Then, the valve 38 is opened, and the water pumping pump 37 injects the water pumped from the dam lake 2 into the two drainage hoses 5A and 5B, respectively. At the same time, the valve 40 is opened, and the air in the drain hose 5 is discharged from the air vent hose 39 attached to the exhaust part 26. As a result, the drainage hose 5 is filled with water. In addition, the water poured into the drain hose 5 does not necessarily need to be the water in the dam lake 2, and may be water taken from other water sources. And when water comes out from the front-end | tip of the air vent hose 39, since the inside of the drainage hose 5 will be in the state substantially filled with water, while stopping the water injection by the water injection pump 37 and closing the valve 38, Then, the valve 40 of the air vent hose 39 is closed, and the filling of water is finished.

  In addition, since the water injection part 25 and the exhaust part 26 are provided in the connector 9 which connects two drain hose 5A, 5B, it is necessary to provide the water injection part 25 and the exhaust part 26 in the drain hose 5A, 5B itself. Therefore, a very common drain hose 5 can be used. Further, the connector 9 provided with the water injection part 25 and the exhaust part 26 is installed on the top part 1 a of the levee part 1. Here, the top portion 1 a of the levee portion 1 damming up the water of the dam lake 2 is normally at the highest position in the laying path of the drainage hose 5. In this case, since the water head pressure does not act on the water injection section 25, water can be injected with the small water injection pump 37, and air can be easily discharged from the drain hose 5.

  Next, the air packers 31 and 32 are removed from the end portions 30a and 30b of the two drainage hoses 5A and 5B in a state where the end portion 30a of the drainage hose 5A is submerged in the dam lake 2, respectively. More specifically, as shown in FIG. 8, when the valve 35 is opened and the air packer 31 is evacuated and deflated, the air packer 31 is pushed out from the end 30a by the water pressure, and the end on the dam lake 2 side. Part 30a is opened. Subsequently, when the valve 36 is opened and the air packer 32 is evacuated and deflated, the air packer 32 is pushed out from the end 30b by the water pressure (+ water head pressure), and the end 30b on the drainage position 3 side is opened. The Then, due to the principle of siphon, a flow of water from the dam lake 2 to the drainage position 3 is generated in the drainage hose 5, and the water in the dam lake 2 is continuously drained. 3 to the drainage basin 8.

  In the second embodiment, the drainage hose 5 is laid from the dam lake 2 over the embankment part 1 to the drainage position 3 on the skirt side, and the end portions 30a and 30b of the drainage hoses 5A and 5B are respectively sealed. The water is filled in the drain hoses 5A and 5B. In this state, when the end portions 30a and 30b are opened, the water in the dam lake 2 is sucked into the drainage hose 5 and flows out to the drainage position 3 on the opposite side over the bank 1. Therefore, the water in the dam lake 2 can be easily drained to the drainage position 3 without using a drain pump.

  In the second embodiment, it is necessary to inject water into the drainage hose 5 with the water injection pump 37. The water injection pump 37 supplies the integrated water of the drainage hose 5 into the drainage hose 5 within a certain time. It is sufficient if it has a capacity sufficient for injection, and a small pump is sufficient as compared with a drainage pump installed to continuously drain the water of the dam lake 2. Therefore, it is easy to carry-in work such that it can be carried into the site by human power, and the installation place on the site is small.

  Next, a modified form of the second embodiment will be described. However, components having the same configuration as in the second embodiment are denoted by the same reference numerals and description thereof is omitted as appropriate.

1] If air enters the drainage hose 5 from the end 30b of the drainage hose 5 on the drainage position 3 side that is not submerged during drainage, the watertight state may be canceled and drainage may stop. Therefore, in order to reliably prevent the ingress of air, a watertight (non-water-permeable) bag body may be attached to the end portion 30b of the drainage hose 5 on the drainage position 3 side. FIG. 10 is a diagram for explaining a drainage process according to this modified embodiment. FIG. 11 is an enlarged view of the end of the drainage hose 5, (a) is a perspective view, and (b) is a cross-sectional view. As the water-tight bag 51, one formed of a butyl rubber sheet or vinyl chloride tarpaulin can be used.

  As shown in FIG. 10 and FIG. 11, air enters from the open end 50 by attaching a water-tight bag 51 to the end 30 b of the drain hose 5 on the drainage position 3 side so as to cover the open end 50. It is prevented. However, if the bag body 51 completely covers the opening end 50 of the drainage hose 5, there is no place for the discharged water, so that the outer surface of the end portion 30b and the bag body 51 are connected as shown in FIG. A pipe 52 (preferably a plurality) is attached between them to form a discharge path for the water discharged from the drain hose 5 into the bag body 51 to the outside of the bag body 51. Thereby, drainage from the end portion 30b can be continuously performed while the bag body 51 prevents air from entering from the opening end 50 of the end portion 30b.

  As shown in FIG. 11, if one end of the pipe 52 protrudes from the opening end 50 of the drainage hose 5 in the bag body 51, the bag body 51 is separated from the opening end 50 by one end of the pipe 52. Since the done state is maintained, the bag body 51 is prevented from preventing drainage. Note that the air packer 32 pushed out from the end portion 30 b at the time of opening is received by the bag body 51 covering the open end 50. Accordingly, it is possible to prevent the air packer 32 from flowing due to the water flow from the opening end 50 during drainage.

2] A drop-off preventing member for preventing the plug member from coming off (dropping off) may be attached to the end of the drain hose 5. In addition, a drop-off prevention member may be attached to both the end 30a on the dam lake 2 side and the end 30b on the drainage position 3 side of the drain hose 5, or a drop-off prevention member is attached only to one end. May be. However, in addition to the water pressure of the injected water, the water head pressure acts on the air packer 32 (second plug member) attached to the end 30b of the drainage hose 5 on the drainage position 3 side. Easy to come off while filling the water. Therefore, it is preferable that the drop-off preventing member is attached at least to the end 30b on the drainage position 3 side.

  Examples of the drop-off prevention member are given below. If the bag body 51 and the pipe 52 are attached to the end 30b on the drainage position 3 side as shown in FIG. 11, the two U-shaped pipes 55 are further connected as shown in FIG. It attaches to the outer peripheral surface of the edge part 30b of the drainage hose 5 with the several pipe 52 for drainage. Thereby, a part of the two pipes 55 (drop-off prevention member) has a shape straddling the open end 50 of the drainage hose 5, and the inflated air packer 32 is prevented from coming off from the end 30b. As shown in FIG. 12B, when the air packer 32 is deflated, the air packer 32 slips out of the end 30b and passes between the two pipes 55 and is received by the bag body 51. .

  Alternatively, as shown in FIG. 13, after the fixing air packer 56 is put in the bag body 51, the bag body 51 is fixed to the end portion 30 b of the drainage hose 5, and the fixing air packer 56 (drop-off preventing member). The air packer 32 that seals the end 30b may be prevented from coming off by inflating the air by injecting the air into the air. When opening the opening end 50, first, the air is removed from the fixing air packer 56, and then the air in the sealing air packer 32 is drawn out. It will be extruded from the part 30b. At this time, the two air packers 32 and 56 in a deflated state are both received by the bag body 51 and are not washed away by the water flow.

  The application of the drop-off preventing member is not limited to the form in which the bag body 51 is attached to the end 30b of the drainage hose 5, as shown in FIGS. That is, even when the end portion 30b does not have the bag body 51, it is possible to use a drop-off preventing member having an appropriate configuration such as the pipe 55 shown in FIG. 12 attached to the end portion 30b. is there.

3] Also in the second embodiment, as shown in FIG. 14, one drainage hose 5 may be laid from the dam lake 2 to the drainage position 3. However, in this embodiment, since there is no connector 9, a water injection part 25 and an exhaust part 26 are provided in advance on a part of the drainage hose 5 to be laid (for example, the part installed on the top part 1a of the levee part 1 in FIG. 14). Must be provided.

4] The water injection part 25 and the exhaust part 26 of the drainage hose 5 can be injected and exhausted even if they are provided at the dam lake 2 side or at the drainage position 3 side at a position lower than the top part 1a. It is. However, as the water injection section 25 is located at a lower position, a larger water head pressure acts, and it is necessary to use a pump having a high head as the water injection pump 37. Moreover, when the exhaust part 26 exists in the position lower than the top part 1a, air tends to accumulate in the part located in the top part 1a of the drainage hose 5, and discharge | emission of air becomes a little difficult.

5] For sealing the end of the drainage hose 5, a method of inserting a plug member such as the aforementioned air packer into the end is preferable in order to securely seal the end, but is not limited thereto. A member having a shape such as a bag shape or a plate shape may be sealed by attaching the end portion of the drainage hose 5 so as to cover the open end.

DESCRIPTION OF SYMBOLS 1 Levee part 1a Top part 2 Dam stop 3 Drainage position 5 Drainage hose 6 Reversing machine 9 Connecting tool 22 Leg part 25 Water injection part 26 Exhaust part 31 Air packer (1st plug member)
32 Air packer (second plug member)
37 Water injection pump 50 Open end 51 Bag body 52 Pipe 55 Pipe 56 Fixing air packer

Claims (13)

A draining method for a dammed lake where water is dammed by accumulated earth and sand,
A drainage hose is laid across the dam lake and a drainage position that is on the opposite side of the dam lake and sandwiching a levee that dams the water of the dam lake and is lower than the dam lake. Hose laying process;
A filling step of filling the drainage hose with water while discharging air in the drainage hose laid;
Equipped with a,
In the hose laying step,
At the drainage position, turn over and fix one end of the drainage hose,
The fluid pressure is applied to the inside of the inverted portion of the hose to reverse the front and back of the hose, and the tip of the reverse is advanced by the fluid pressure to pass the dam part from the drainage position to the dam. A drainage method for a dam lake, wherein the drain hose is laid to the lagoon . In the filling step, with the end of the drain hose on the side of the dam lake submerged in the dam lake, the air in the drain hose is sucked and discharged from the drain position side, The method for draining a dam lake according to claim 1, wherein water in the dam lake is drawn into the drain hose. Before the filling step, each of the drain hose, the end on the dam lake side and the end on the drainage position side are sealed,
The drainage hose is provided with a water injection part and an exhaust part, and in the filling process, water is injected into the drainage hose from the water injection part by a water injection pump, and air in the drainage hose is discharged from the exhaust part. Drain and fill the drain hose with water,
2. The drainage method for a dam lake according to claim 1 , wherein after the filling step, an end portion on the dam lake side and an end portion on the drain position side of the drain hose are each opened. A watertight bag is attached to the end of the drainage hose on the drainage position side so as to cover the open end, and between the outer surface of the end of the drainage hose and the bag, The drainage method of the dam lake according to claim 3 , wherein a pipe for discharging water to the outside is attached. A draining method for a dammed lake where water is dammed by accumulated earth and sand,
A drainage hose is laid across the dam lake and a drainage position that is on the opposite side of the dam lake and sandwiching a levee that dams the water of the dam lake and is lower than the dam lake. Hose laying process;
A filling step of filling the drainage hose with water while discharging air in the drainage hose laid;
Equipped with a,
Before the filling step, each of the drain hose, the end on the dam lake side and the end on the drainage position side are sealed,
The drainage hose is provided with a water injection part and an exhaust part, and in the filling process, water is injected into the drainage hose from the water injection part by a water injection pump, and air in the drainage hose is discharged from the exhaust part. Drain and fill the drain hose with water,
After the filling step, the end of the drainage hose on the side of the dam and the end of the drainage position side are opened,
A watertight bag is attached to the end of the drainage hose on the drainage position side so as to cover the open end, and between the outer surface of the end of the drainage hose and the bag, A drainage method for a dam lake, characterized by attaching a pipe for discharging water to the outside . The drainage method for a dam lake according to claim 4 or 5 , wherein one end of the pipe protrudes from the opening end of the drainage hose in the bag body. The drainage method for a dam lake according to any one of claims 3 to 6 , wherein the water injection section and the exhaust section are provided in a portion of the drainage hose located at the top of the levee section. . In the hose laying step, the drain hose is separately laid in a first section from the top to the dam lake and a second section from the top to the drainage position,
The two drain hoses respectively laid in the first section and the second section are connected to a connector installed on the top of the levee, and the two drain hoses are connected via the connector. Concatenate,
The drainage method for a dam lake according to claim 7 , wherein the water injection section and the exhaust section are provided in the connector. 9. The drainage method for a dam lake according to claim 8 , wherein the connector has a curved leg. By inserting the first plug member and the second plug member into the end of the drainage hose on the side of the dammed lake and the end of the drainage position, respectively, the end on the side of the dammed lake and the drainage position are inserted. The draining method of the dam lake according to any one of claims 3 to 9, wherein each of the side ends is sealed.   The drainage method of a dam lake according to claim 10, wherein at least one of the first plug member and the second plug member includes an expansion body that expands by injecting air.   A drop-off prevention member for preventing the plug member from falling off from the drain hose is attached to at least one of the drain hose end and the drain position end. The drainage method of the dam lake of 10 or 11. The drainage hose has a hose body made of a tubular fabric,
The drainage method for a dam lake according to any one of claims 1 to 12, wherein both an inner surface and an outer surface of the hose body are covered with a synthetic resin coating.