JP5092832B2 - Falling water sound and falling water flow attenuation structure in water - Google Patents

Description

  The present invention relates to a falling water sound / falling water flow attenuation structure in a water area such as a water channel having a site where flowing water falls, such as a drop head.

  In recent years, with the expansion of urbanization and the mixing of agricultural and residential areas, the number of houses has increased near water facilities such as gates and drop works. For this reason, the falling water sound of a waterway has become a problem with environmental pollution. Falling water sounds include audible sounds that humans can recognize and low-frequency sounds that cannot be recognized, and low-frequency sounds cause physical problems such as shoji and rattling of window frames, and mental problems such as headaches and sleeplessness. May trigger. In addition, in the drop work, a wave generated by the falling water vein propagates downstream, the overflow rate of the falling work provided downstream fluctuates, and the falling water vein fluctuates, which may cause discomfort. Conventionally, as countermeasures against falling water sound, there are two methods, one for water sound source and one for generated sound. As a measure against the sound source, it is known to reduce the falling water sound by providing an inclined surface in the drop work and changing the falling flow into the inclined flow. As measures against the generated sound, it is known to cover the water channel and to cover the water channel or to install a plate having a sound absorbing function on the side wall of the water channel. Among the conventional reduction techniques for attenuating water noise, for example, in a configuration in which an inclined surface is provided for the drop head, the falling water sound itself can be reduced, but the falling water flow that goes down the inclined surface enters the downstream water surface. However, there is a problem that water noise is generated at the point of entry. For this reason, there is a problem that the inclined surface must be linear and the dimensions in the upstream and downstream directions are long, and such a technique cannot be employed in places where there are topographical restrictions. Also, when installing a lid or sound absorbing plate, the sound propagates in the air, so the effect cannot be expected even if it is installed only at the location of the sound source, so the installation section must be lengthened and the cost increases. There is. For this reason, conventionally, in order to solve such a problem, as a technique for reducing the water noise due to the falling water vein, for example, a technique in which a bypass is provided outside the side wall of the drop work is known (see Patent Document 1).

The thing of this patent document 1 forms an inclined surface between the upstream high floor part of a water channel, and a downstream low floor part, and an upstream high floor part downstream end part and a downstream low floor are formed on the outer side of a water channel side wall. A bypass passage is formed to connect with the upstream end of the portion, and the inner surface of the side wall of the downstream low floor portion is formed as a rough rough surface.
JP2003-147754 (3rd page, FIG. 1)

  However, the above conventional technique has a problem that the drop work itself has to be applied, which not only complicates the drop work but also increases the cost.

  The present invention was made in order to solve the above-mentioned problems, and with a simple configuration, it is possible to greatly suppress the falling water noise and the undulation of the downstream part, and the head after construction is not limited by topographical constraints. An object of the present invention is to provide a falling water sound / falling water damping structure for a water area that can be installed in a work and can be reduced in size and greatly reduced in cost.

  The falling water sound / falling water flow damping structure according to claim 1 of the present invention forms a housing by arranging a plurality of floating materials having buoyancy and connecting them to each other so that they can move relative to each other. In addition to providing a gap to allow water to pass through, connect the upstream end of the chassis to the stepped part where the flowing water falls, so that the falling water sound / falling water flow in the water area that allows the falling water stream to flow into the upper surface of the chassis A structure for damping is provided, and a restraining means is provided for connecting the downstream end portion of the casing and the bottom of the water area downstream from the downstream end portion to suppress free vertical movement of the downstream end portion of the casing. It is a thing.

  In the falling water sound / falling water flow damping structure according to claim 1, a plurality of floating materials having buoyancy are arranged side by side and connected to each other so as to be able to move relative to each other. A structure that attenuates the falling water sound and falling water flow in the water area that allows the passage of the falling water flow into the upper surface of the enclosure by connecting the upstream end of the enclosure to the step where the running water falls, and providing a gap that allows passage By providing a restraining means for connecting the downstream end of the casing and the bottom of the water area downstream of the downstream end to suppress free vertical movement of the casing downstream end. When the falling water flow in the water area flows into the top surface of the housing, the inflowing water flows along the top surface of the housing that bends freely by the force received from the water, and the housing pushes up the water by buoyancy. At this time, the falling water flow causes a part of the water flow to drop downward from the voids of the housing, and a part flows along the upper surface. Since the falling water flow does not directly enter the dropped water surface, the generation of water noise due to the falling is suppressed. If the water is bent and sinks freely by the water flow received from above, or if the undulation movement occurs due to the pushing up of the water by buoyancy, the undulation movement is propagated from the upstream side to the downstream side, and reaches the downstream end. However, since the movement of the downstream end is restricted by the restraining means, the twisting movement is attenuated and suppressed. Therefore, the undulating movement is suppressed and the upper and lower sides are held almost flat. For this reason, even if the distance between the upstream and downstream of the housing is short, part of the water flow that flows along the upper surface leaks downward from the gap, and the occurrence of undulations in the downstream portion is suppressed, and the sound of the waves is also suppressed. The dimension between the upstream and downstream of the housing can be shortened. By reducing the length between the upstream and downstream of the housing, it is difficult for sediment to flow down on the upper surface of the housing.

  The falling water noise / falling water flow damping structure of the water area according to claim 2 of the present invention is a variation in which the shape of the upstream end side is maintained below the upstream end side of the casing to suppress the vertical movement of the casing. A suppression means is provided.

  In the falling water sound / falling water flow damping structure of the water area according to claim 2, fluctuation suppressing means is provided below the upstream end side of the casing to maintain the shape of the upstream end side and suppress the vertical movement of the casing. As a result, when the falling water flow of the water area flows into the upper surface of the housing, the inflowing water flows in a lump along the upper surface on the upstream side of the housing, and the upstream end of the housing is moved downward. While trying to push down, the housing receives a push-down force while maintaining the shape of the upstream end side. And while a falling water flow flows along the upper surface of the housing upstream end side, while dropping a part of water flow from the space | gap between housings, a part flows downstream along the upper surface. For this reason, since the falling water flow does not directly enter the dropped water surface, the generation of water noise due to the falling is suppressed. Moreover, since a part of water flow that flows along the upper surface gradually leaks downward from the gap, the occurrence of undulations in the downstream portion is suppressed, and the sound of waves is also suppressed. When the buoyancy overcomes, the upstream end side of the enclosure pushes up the water and floats up, and when it receives a falling water flow that overcomes buoyancy, it repeatedly sinks downward. Severe movement is suppressed, and the movement transmitted from the upstream end side to the downstream side is attenuated. In this way, the free movement of the downstream end is restricted by the restraining means, and the vertical movement of the upstream end is suppressed by the fluctuation propagation preventing means, so that the occurrence of ripples in the downstream part is reliably suppressed, Is also suppressed, and the dimensions between the upstream and downstream of the housing can be shortened. By reducing the length between the upstream and downstream of the housing, it is difficult for sediment to flow down on the upper surface of the housing.

  In the falling water sound / falling water flow damping structure according to claim 3, the restraining means includes a rope that has one end connected to the downstream end of the housing and the other end fixed to the bottom of the water body to maintain tension. It is designed to be prepared.

  In the falling water sound / falling water flow damping structure according to claim 3, the restraining means includes a rope that has one end connected to the downstream end of the housing and the other end fixed to the bottom of the water body to maintain tension. By being provided and configured, the installation is easy and the cost is reduced.

  In the falling water sound / falling water flow damping structure of the water area according to claim 4, one end of the fluctuation suppressing means is connected to the upstream end of the housing, and the other end is downstream of the upstream end of the housing. And it is comprised including the board | plate material connected by forming a space | gap between the housing | casing curved upwards.

  In the falling water sound / falling water flow damping structure according to claim 4, one end of the fluctuation suppressing means is connected to the upstream end of the casing, and the other end is downstream of the upstream end of the casing. In addition, by providing a plate member that is connected by forming a gap with the casing that is curved upward, when the falling water flow flows into the upstream end side of the casing, Since the upstream end side moves up and down integrally with the plate body while maintaining the curvature, fine movement and intense movement are suppressed, and movement propagated from the upstream end side to the downstream side is attenuated.

  In the falling water sound / falling water flow damping structure according to claim 5, the floating member is constituted by a pillar member having through holes on both sides of the side part, and the column body is placed sideways by matching the through holes. In addition to arranging the spacers between the column members and connecting them with ropes, the frame is arranged in the water area so that the direction in which the column members are arranged matches the flow direction of the falling water flow.

  In the fall water sound / falling water flow damping structure according to claim 5, the floating member is constituted by a pillar member having through holes on both sides of the side part, and the column body is placed side by side with the through holes being matched. In addition to arranging the spacers between these pillars and connecting them with ropes, the housing is placed in the water area so that the direction in which the pillars line up matches the flow direction of the falling water flow. When the water flow flows into the upper surface of the housing, the incoming water becomes easy to flow along the flat upper surface of the housing and stabilizes the behavior of the falling water flow. In addition, since the frame is installed so that the direction in which the pillars are arranged matches the flow direction, the frame will bend in accordance with the movement of the water flow that occurs in the flow direction, so the falling water flow that has flowed into the top surface hits. Disappears and the force is attenuated.

  In the falling water sound / falling water flow damping structure according to claim 6, the enclosure is installed in a water channel where the falling water flow flows from the upstream high floor to the downstream low floor, and the upstream end of the enclosure is disposed These are fixedly attached to the upper ends of the step portions formed between the upstream and downstream side floor portions.

  In the falling water sound / falling water flow attenuating structure according to claim 6, the enclosure is installed in a water channel in which the falling water flow flows from the upstream high floor to the downstream low floor, and the upstream end of the enclosure is When the falling water flow flows from the upstream high floor side to the upper surface of the frame upstream by being fixedly attached to the upper end of the step portion formed between these upper and lower floors, it is pushed downstream along the upper surface. The water drops gradually without falling suddenly, and while the water flows from the gap while leaking, the water flow is suppressed and the water flow is stabilized.

  In the falling water sound / falling water damping structure of the water area according to the present invention, a plurality of floating materials having buoyancy are arranged side by side and connected to each other so as to be able to move relative to each other, and a casing is formed. A structure that attenuates the falling water sound and falling water flow of the water area that connects the upstream end of the housing to the stepped part where the flowing water falls and flows the falling water flow into the upper surface of the housing. In addition, a restraining means for connecting the downstream end portion of the casing and the bottom of the water area downstream of the downstream end portion to suppress free vertical movement of the downstream end portion of the casing is provided. With a simple structure, it is possible to greatly suppress the sound of falling water and undulations in the downstream area, and it can be installed in the drop work after construction without being restricted by topographical constraints, and the structure is greatly reduced in size. The cost can be reduced.

  The purpose of eliminating the falling water sound and waves in the channel with a simple configuration is to arrange the pillars with a flat surface on the top with the through holes aligned side by side, and arrange the spacers between the pillars with a rope. Connected to form a housing, and this housing is installed in a water channel where a falling water flow flows from the upstream high floor to the downstream low floor, and the upstream end of the housing is connected to these upstream and downstream floors. It is fixedly attached to the upper end of the stepped portion formed in the middle, and the other end of the rope, one end of which is connected to the downstream end of the frame, holds tension at the bottom of the water area downstream from the downstream end. The other end of the plate body, one end of which is connected to the upstream end of the housing, is downstream of the upstream end of the housing, and the housing is curved upward to bend the housing. This was realized by forming a gap between them and connecting them.

  Hereinafter, the present invention will be described with reference to embodiments shown in the drawings. FIGS. 1A and 1B are a side view showing a falling water sound / falling water flow attenuation structure in a water area according to an embodiment of the present invention, and an explanation showing a behavior of a falling water flow at a mounting position of the attenuation structure, respectively. 2, (A) to (C) of FIG. 2 are a side view of a casing constituting a part of the damping structure, a front view of a column member constituting a part of the casing, and a plan view of the casing, respectively. . The falling water sound / falling water flow attenuation structure 2 of the water area according to the present embodiment is a water channel 5 in which the falling water flow W1 flows from the upstream high floor portion 3 to the downstream low floor portion 4 as shown in FIG. And a housing 10 installed in the water channel 5. In the water channel 5, a step portion 6 that rises substantially vertically is formed between the downstream end of the upstream high floor portion 3 and the upstream end of the downstream low floor portion 4. The housing 10 is fixedly attached to the upper portion of the stepped portion 6. FIG. 1B is an explanatory diagram of the behavior of the falling water flow by comparing the state in which the casing 10 is not attached to the step portion 6 of the water channel 5. When the frame 10 is not present, the flowing water flowing from the raised floor 3 on the upstream side (the right side of FIG. 1B) suddenly falls at the stepped portion 6 and becomes a lump of water as falling flowing water W1 on the downstream side. It hits the water surface of the low floor part 4 and generates a falling water sound. Furthermore, as a result of the falling water W1 colliding violently, a turbulent flow is generated to generate a ripple on the downstream side, and a ripple sound accompanying the ripple is generated. A solid line W in FIG. 1B indicates the behavior of the flowing water surface.

  As shown in FIGS. 2A to 2C, the housing 10 includes a large number of prisms (floating members, column members) 13 having a flat surface 11 formed on the upper surface. The rectangular column member 13 is formed by cutting a timber having a square cross section having buoyancy in a predetermined length according to the width of the water channel 5. In the prism member 13, through holes 12 </ b> A and 12 </ b> B are formed in the same direction on the side surfaces on both ends in the longitudinal direction. The casing 10 has a large number of prisms by passing the other ends of a pair of ropes (or wires, strips) 15A and 15B, each having a fixing tool 14 attached to one end, through the through holes 12A and 12B of the prism member 13, respectively. The material 13 is connected in the lateral direction. The hole diameters of the through holes 12A and 12B are larger than the diameters of the ropes 15A and 15B, and the ropes 15A and 15B pass smoothly through the through holes 12A and 12B.

  To assemble the housing 10, first, the other ends of the ropes 15A and 15B are passed through the through holes 12A and 12B of the integral prismatic member 13, and then the other ends of the ropes 15A and 15B are made of rubber. The annular spacer 16 is passed. The inner diameter of the spacer 16 is larger than the ropes 15A and 15B, and is passed through the ropes 15A and 15B with play. The outside of the spacer 16 has a size larger than the diameters of the through holes 12A and 12B. Thus, the prisms 13 and the spacers 16 are alternately passed through the ropes 15A and 15B, and when the number of the prisms 13 reaches a predetermined number, the other prisms 15A and 15B are connected to the last prism by the fixing tool 17. The prism 10 is fixed to the member 13 to prevent the prism member 13 from coming off, and the housing 10 is assembled.

  The number of prisms 13 is derived in advance by experiments. In this performance experiment, the length of the casing 10 in the flow direction, the size of the prisms 13, and the size of the gaps between the prisms 13 that can exhibit the silencing performance and the silencing performance against the falling water flow at the step portion 6 of the water channel 6. Will be guided. That is, a model of the water channel 5 is created in advance, and a test body of the housing 10 that can appropriately adjust the number of prisms, different sizes of prisms, different sizes of spacers, and the like is manufactured. The performance test which can exhibit the silencing performance and the silencing performance against the falling water flow at 6 is performed. Then, from the performance test results, the number of prisms that can obtain desired performance with the smallest number is determined for a prism having a certain size and a casing having a gap having a certain width. Further, not only the flow direction length of the housing 10 is determined by the number of the prisms 13 but also the preferred size of the prisms 13 itself, that is, the vertical and horizontal dimensions of the rectangular cross section, based on data confirmed in advance by experiments. Is also set. As described above, the housing 10 has a large number of prisms 13 arranged in the lateral direction connected by the ropes 15 </ b> A and 15 </ b> B via the spacers 16, and the gaps between the adjacent prisms 13 by the spacers 16. S1 is formed. The frame 10 is configured to swing in response to the regulation of the ropes 15 </ b> A and 15 </ b> B when the prismatic member 13 receives a force from the outside while floating in the water. In other words, when a force is applied from different directions to different parts of the flow direction of the housing 10, it is tortuous.

  The housing 10 is configured such that both the fixing tools 14 of the ropes 15 </ b> A and 15 </ b> B are fixed to the upper end portion 6 </ b> A of the stepped portion 6. For this reason, when water flows from the upstream side of the step portion 6 of the water channel 5, the water flow flows down the upper surface 10 </ b> A of the housing 10 from the upstream side to the downstream side. When the pressure from above overcomes the pressure (buoyancy) from below, the housing 10 floating in the water is recessed. Further, when a water flow flows on the upper surface 10A of the housing 10, it flows downward through the gap S1.

  By the way, in the falling water sound / falling water flow damping structure 2 of the water area according to the present embodiment, as shown in FIG. 1A and FIG. The connecting tool 22 having a U-shaped metal fitting in the center of the lower end of the downstream end prismatic material 13D on the downstream side low floor portion 4 has a U-shaped metal fitting in the substantially central position in the width direction. 23 are provided. Both ends 20A and 20B of a rope (restraining means) 20 provided with a turnbuckle 24 are connected to the connecting tool 22 and the connecting tool 23 while maintaining tension. Since the rope 20 holds the tension by the turnbuckle 24 and connects the downstream end prismatic member 13D and the downstream low floor portion 4, the downstream end prismatic member 13D of the housing 10 receives the force from the outside and moves up and down. Even if it tries to move, the movement is suppressed.

  As shown in FIG. 1A and FIG. 4, a plate 30 (fluctuation suppressing means) is attached to the casing 10 on the back surface on the upstream side. The plate body 30 has an upstream end 31A connected to the upstream end prismatic member 13U of the housing 10 via a connection fitting 32, and a downstream end 31B downstream of the upstream end prismatic material 13U of the housing 10. It is connected to the material 13M via a connection fitting 32. As shown in FIG. 2A, the plate 30 is connected to the housing 10 by bending the prism member 13 on the upstream end side upward, and the upstream curved portion of the housing 10 is connected. A gap S <b> 2 is formed between the gap 33. Since the plate body 30 is thus formed with the gap S2 between the casing 10 and moves integrally with the upstream curved portion 33 of the casing 10, the upstream side of the upstream end side of the casing 10 is upstream. The shape of the side curved portion 33 is maintained and the movement of the vertical movement of the housing 10 is suppressed.

  Next, the operation of the falling water sound / falling water damping structure 2 in the water area according to the embodiment will be described. In the falling water sound / falling water flow damping structure 2 according to the embodiment, the upstream end prismatic member 13U of the housing 10 is attached to the stepped portion 6 upper end portion 6A of the water channel 5 via both fixtures 14, and the downstream end. The prismatic member 13 </ b> D is connected to the downstream low floor 4 in a state of being pulled through the rope 20, and a plate body 10 that moves integrally with the housing 10 is attached to the rear surface on the upstream end side of the housing 10. It has been.

  For this reason, when the water flow flowing through the upstream side high floor portion 3 reaches the stepped portion 6, it flows into the upper surface 10 </ b> A of the curved portion 33 of the housing 10 in an attempt to flow down. The falling water flow W1 is blocked by the housing 10 before reaching the water surface of the downstream low floor portion 4 and flows down along the upper surface 10A. At this time, since the falling water flow W1 reaches the upper surface 10A while maintaining the water level of the upstream side high floor portion 3, the falling water flow W1 becomes a mass of water and applies a downward pressure to the curved portion 33 of the housing 10 to sink. On the other hand, the bending force 33 and the plate body 30 of the housing 10 give a force to push up the falling water flow W1 that has become a lump due to buoyancy. For this reason, as shown to (A) of FIG. 1, the housing 10 draws the loose curved surface Fc from an upstream end. The falling water flow W1 that has become a mass flows down the curved surface Fc portion of the upstream curved portion 33 of the upper surface 10A of the housing 10 and flows downward from the gap S1 through the housing 10 and flows on the upper surface 10A. The amount of water going down decreases. At this time, when the buoyancy is overcome, the upstream end side bending portion 33 of the housing 10 pushes up the water and floats up. When receiving the falling water flow W1 superior to the buoyancy, the upstream end side bending portion 33 repeatedly sinks downward. Since the plate body 30 and the plate body 30 move up and down as a unit, fine movement and intense movement are suppressed, and movement propagated in a short section from the upstream end side to the downstream side is attenuated. For this reason, the dimension between the upstream and downstream ends of the housing 10 can be shortened, and the housing can be miniaturized.

  The falling water flow W1 reduces the amount of water as it passes through the curved surface Fc. Since the curved surface Fc has a large number of voids S1 in the water channel width direction, the falling kinetic energy reaches the terminal Fe of the curved surface Fc. Has fallen. As described above, the falling water flow W1 is absorbed and attenuated as the curved surface Fc of the casing 10 passes, and does not enter the downstream water surface as shown in FIG. For this reason, generation | occurrence | production of a falling water sound is suppressed. Thus, the falling water flow W2 in which the amount of water is reduced and the kinetic energy of falling is further guided to the downstream flat surface Ff of the upper surface 10A and flows down there. Even while the falling water flow W2 flows down the downstream flat surface Ff of the upper surface 10A, the force lifted by the buoyancy of the housing 10 works and flows down from the gap S1 through the housing 10 and flows down the upper surface 10A. The amount of water going down decreases. At this time, if a gentle vertical movement occurs in the upstream end side curved portion 33 of the casing 10, the undulating movement of the vertical movement propagates downstream and is transmitted to the downstream end prismatic material 13 </ b> D of the casing 10. However, since the movement of the downstream end prismatic material 13D is restricted by the rope 20, the movement is attenuated and suppressed. For this reason, even if the upstream end side curved portion 33 is moved up and down, the casing 10 is restrained from undulating in a short section from the upstream end side to the downstream side, and is held substantially flat between the upstream and downstream sides. Therefore, in addition to the absence of turbulent flow and the occurrence of undulations, the size between the upstream and downstream ends of the housing 10 can be shortened, and the housing can be miniaturized. That is, in the case of the water channel 5 without the casing 10, the water flow in the stepped portion 6 is generated due to the disturbance of the behavior caused by the drop, whereas in this embodiment, the casing has a short dimension in the flow direction. There is no occurrence of such waves and no sound of waves. Thus, in the falling water sound / falling water flow damping structure 2 of the water area according to the present embodiment, when the falling water flow W1 on the upstream side reaches the stepped portion 6, the housing 10 receives a buffering action and loses the amount of water. Since the falling kinetic energy is scraped off and smoothly flows down along the upper surface 10A of the housing 10, there is no occurrence of falling water sound or undulating sound.

  As described above, in the falling water sound / falling water flow attenuation structure 2 of the water area according to the present embodiment, since the plate body 30 is provided, for example, in the case of the frame without the plate body 30, the step difference of the drop work is large. Then, the water flow from the upstream side high floor part 3 jumps without being along the upper surface of the housing, so that the falling sound is generated. On the other hand, the water flow from the upstream side high floor part 3 is caused by the presence of the plate body 30. It always flows down along the upper surface of the housing 10. In addition, if there is no cable 20, the frame is drawn to the falling point of the water flow by the water flow jumped from the upstream side high floor part 3, becomes a convex shape with respect to the floor 4 of the water channel 5, and falls at the falling point In contrast to the occurrence of sound, the presence of the rope 20 does not cause a large depression because the downstream side is always pulled even if a force is applied to a part of the housing 30. Thus, the falling water noise / falling water flow damping structure 2 in the water area according to the present embodiment is effective even when the head of the head is large.

  In addition, in the said Example, although it has tried to provide both the rope 20 and the plate body 30 in the housing 10, it is not restricted to this, and it may be made to provide only either one. Needless to say. Furthermore, although a large number of prismatic materials are arranged side by side, the present invention is not limited to this, and block-like floating materials may be arranged in a plane and connected to each other by a rope in the vertical and horizontal directions. Moreover, in the said Example. The space 16 is provided between the prisms 13 by the spacers 16 to allow water to pass downward. However, the present invention is not limited to this, and a hole that allows water to pass downwards is provided in the floating material itself. May be. Furthermore, in the said Example, although the upstream edge part of the housing 10 is fixed to the upper end of the step part 6 of a drop work, it is not restricted to this, For example, the step part 6 inclines Needless to say, the upper and lower positions of the stepped portion 6 may be determined according to the behavior of water. Further, in the above embodiment, the frame 10 is installed in the head work, but the present invention is not limited to this, and it is installed in the place of the topography that is naturally formed in the river or the lake. May be. Further, it may be installed in a place where water is dropped or a gate in a factory or facility. In the above embodiment, the prisms 13 are connected by the ropes 15A and 15B. However, the present invention is not limited to this, and a connecting tool is provided between the prisms so that adjacent prisms can be slidably connected to each other. You may make it do. Furthermore, in the above-described embodiment, the rectangular columnar material 13 having a rectangular cross section with a flat upper surface is used as the floating member of the casing 10, but the present invention is not limited thereto, and a round member with a circular cross section, an elliptical cross section, Needless to say, it may be wood having a semicircular section, a triangular section, or a polygonal section. Further, the upstream surface of the upper surface 10A of the housing 10 may be formed in a shape that attenuates the falling water flow, or the space on the upstream side is made larger than the space on the downstream side to reduce the water flow. May be increased. In the above embodiment, the floating material is made of wood. However, the present invention is not limited to this, and any material having a predetermined strength and buoyancy may be used. Good. Furthermore, in the said Example, although the through-holes 12A and 12B are provided in the prismatic material 13, it is not restricted to this, It replaces with the through-holes 12A and 12B and at least any one of the upper and lower surfaces of a prismatic material. An annular metal fitting may be screwed to pass the rope, and an elastic member (buffer member) may be attached to the side wall of the prismatic material to form a gap between the prismatic materials. Further, instead of the through holes 12A and 12B, grooves may be formed on both sides of the prismatic material, and a rope may be wound around the grooves and tied. Furthermore, in the said Example, although the prism 13 is made into the same water channel width direction length, it is not restricted to this, A water channel width direction length is gradually shortened as it goes downstream, and water is poured from both right and left ends. You may make it easy to flow below the body. Moreover, in the said Example, although the one strand 20 is provided in the approximate center of the water channel 5, it is not restricted to this, It distribute | arranges to the both-sides wall side of the water channel 5, and provides two It may be.

(A), (B) is the side view which shows the fall water sound and the fall water flow attenuation structure of the water area which concerns on one Example of this invention, respectively, and explanatory drawing which shows the behavior of the fall water flow in the attachment location of the attenuation structure. . Example 1 (A) thru | or (C) are respectively the side view of the housing | casing which comprises a part of damping structure of FIG. 1, the front view of the pillar material which comprises a part of housing | casing, and the top view of a housing. It is a perspective view which shows the attachment state of the rope of the damping structure of FIG. It is explanatory drawing which shows the board of the attenuation | damping structure of FIG.

Explanation of symbols

2 Falling water sound and falling water flow attenuation structure in the water body 4 Downstream low floor (water bottom)
DESCRIPTION OF SYMBOLS 10 Housing 10A Top surface of housing 13 Square pillar material (floating material)
13D Downstream end prismatic material (downstream end of the housing)
20 Rope (restraint)
30 Plate (Fluctuation suppression means)
33 Curved part (upstream end of the housing)
S1 Gap W1 Falling water flow

Claims (6)

  A plurality of floating materials having buoyancy are arranged side by side and connected to each other so as to be movable relative to each other to form a housing. In this housing, a gap allowing water to pass is provided above and below, and a step in the water area where flowing water falls The structure has a structure for attenuating the falling water sound / falling water flow in the water area where the upstream end of the housing is connected to the housing to allow the falling water flow to flow into the upper surface of the housing, the downstream end of the housing and the downstream end A falling water sound / falling water flow damping structure for a water area, characterized in that a restraining means is provided to connect the bottom of the water area downstream from the water section to suppress free vertical movement of the downstream end of the housing.   The water drop falling sound of the water area according to claim 1, characterized in that a fluctuation suppressing means is provided below the upstream end side of the housing to maintain the shape of the upstream end and suppress the vertical movement of the housing. Falling water flow damping structure.   3. The restraint means is configured to include a rope that has one end connected to the downstream end of the housing and the other end fixed to the bottom of the water body, and holds tension. 4. Falling water sound / falling water flow attenuation structure of water area.   The fluctuation suppressing means has one end connected to the upstream end of the housing and the other end downstream of the upstream end of the housing and forming a gap with the housing curved upward. The falling water noise / falling water flow attenuation structure of a water area according to claim 2 or 3, characterized in that the structure is provided with plate members connected to each other.   The floating material is composed of pillars having through holes on both sides of the side, the frame is aligned with the pillars side by side with the through holes aligned, and spacers are placed between these pillars and connected by ropes. 5. The falling water sound of the water area according to claim 1, wherein the casing is arranged in the water area so that a direction in which the column members are arranged matches a flow direction of the falling water flow. -Falling water flow damping structure.   The enclosure is installed in a water channel where the falling water flow flows from the upstream high floor to the downstream low floor, and the upstream end of the enclosure is fixed to the upper end of the step formed between the upstream and downstream floors. The water fall sound / fall water flow damping structure according to claim 1, wherein the water fall sound and fall water flow damping structure are attached.

Images