JP5393376B2 - Double-pipe tremy device and earth and sand charging method - Google Patents

Description

  The present invention relates to a double-pipe tremy device and a method for introducing earth and sand, and more specifically, when introducing earth and sand into a water bottom, a circulating flow that circulates between a gap between an inner pipe and an outer pipe and the inside of the inner pipe. The present invention relates to a double-pipe tremy device and a method for depositing earth and sand, which are easy to occur and enable smooth earth throwing and suppression of pollution diffusion.

  A method of using a double-pipe tremy device is known (see, for example, Patent Documents 1 and 2) when putting earth and sand into a predetermined range of the bottom of a sea or river. As illustrated in FIGS. 7 to 9, the conventional double tube tremy device 8 described in these patent documents has an opening 4 near the hydrostatic surface of the inner tube 3, and the hopper 7 and the inner tube 3. After that, earth and sand S is thrown into the bottom of the water.

  When the earth and sand S is introduced into the inner pipe 3, the density of the water W inside the inner pipe 3 (mixed water with the earth and sand S) is larger than the density of the water W around the inner pipe 3, so that FIG. As illustrated, the water level inside the inner pipe 3 is lowered. In order to compensate for the lowering of the water level inside the inner pipe 3, water W in the gap between the inner pipe 3 and the outer pipe 2 flows into the inner pipe 3 through the opening 4. At the lower ends of the inner tube 3 and the outer tube 2, the water W flowing out from the inner tube 3 diffuses, but a part of the water W flows into the gap between the inner tube 3 and the outer tube 2. As a result, a circulating flow that circulates between the gap between the inner tube 3 and the outer tube 2 and the inside of the inner tube 3 is generated.

  If new earth and sand S is thrown into the inner pipe 3 before the earth and sand S thrown into the inner pipe 3 flows out of the pipe, this circulation flow is continued without interruption. When the circulating flow is generated, the earth and sand S can be smoothly put into the bottom of the water, so that the construction efficiency is improved.

  However, for example, as the water depth becomes shallower, the earth and sand S thrown into the inner pipe 3 will flow out of the pipe more quickly. It becomes difficult to introduce new earth and sand S into the inner pipe 3 before flowing out of the pipe. In this way, when the time until the earth and sand S thrown into the inner pipe 3 flows out of the pipe becomes short, or when the time interval for putting the earth and sand S becomes longer, new earth and sand S is thrown into the inner pipe 3. Before, the earth and sand S already put into the inner pipe 3 flows out of the pipe. Therefore, the difference between the density of the water W inside the inner pipe 3 and the density of the water W around the inner pipe 3 is reduced.

  As a result, the water surface inside the inner pipe 3 that has been lowered rises as illustrated in FIG. 8 due to the reaction, and the water W inside the inner pipe 3 flows between the inner pipe 3 and the outer pipe 2 through the opening 4. It flows into the gap and the circulating flow stops. Then, as illustrated in FIG. 9, the water surface inside the inner pipe 3 and the water surface of the water W in the gap between the inner pipe 3 and the outer pipe 2 oscillate up and down, and eventually both The density of water W (mixed water with earth and sand S) becomes substantially the same.

  In this way, under conditions where new earth and sand S cannot be introduced into the inner pipe 3 before the earth and sand S charged into the inner pipe 3 flows out of the pipe, the circulating flow is likely to stop, so that the earth and sand S can be smoothly stopped. It was disadvantageous to throw in to the bottom of the water.

JP 2002-129568 A JP 2002-129569 A

  The object of the present invention is to facilitate the formation of a circulating flow that circulates between the gap between the inner pipe and the outer pipe and the inside of the inner pipe when throwing the earth and sand into the bottom of the water, and smooth soil injection and suppression of the diffusion of pollution. The object is to provide a double-pipe tremy device and a method for depositing earth and sand.

  In order to achieve the above object, the double-tube tremy device of the present invention is a double-tube tremy device in which an outer tube is disposed on the outer peripheral side of the inner tube, and an opening is formed on the peripheral wall of the inner tube. It is arranged so that the lower end is below the water level outside the outer pipe. Water flows into the opening through the gap between the inner pipe and the outer pipe, and from the inner pipe to the inner pipe and the outer pipe. A check valve for blocking outflow of water is provided in the gap with the pipe.

  Here, a cover that covers the inner peripheral side of the check valve may be provided. The check valve may be composed of a plate-like valve body and a hinge member provided at the upper end of the valve body, and at least the hinge member of the check valve may be covered by the cover.

  In addition, the earth and sand charging method of the present invention uses a double-tube tremy device in which an outer pipe is disposed on the outer peripheral side of the inner pipe and an opening is formed in the peripheral wall of the inner pipe. In the method of depositing earth and sand to be introduced into the range, the opening is arranged so that the lower end thereof is equal to or lower than the water level outside the outer pipe, and a check valve is provided in the opening, and the earth and sand are placed in the inner pipe. When the water surface inside the inner pipe drops below the opening, the check valve that closes the opening opens and water in the gap between the inner pipe and the outer pipe opens. When the water surface inside the inner pipe is lowered from the opening, the check valve is closed and the water inside the inner pipe is opened. It is characterized by blocking outflow into the gap between the inner tube and the outer tube through the through hole.

  Here, for example, the earth and sand are repeatedly put into the inner pipe using a backhoe bucket.

  According to the present invention, an outer tube is disposed on the outer peripheral side of the inner tube, and the lower end of the opening of the double-tube tremy device having an opening on the peripheral wall of the inner tube is below the water level outside the outer tube. In this opening, water flows into the inner tube from the gap between the inner tube and the outer tube, and the outflow of water from the inner tube to the gap between the inner tube and the outer tube is blocked. By providing the check valve, the check valve that closes the opening is opened when the sand is poured into the inner pipe and the water level inside the inner pipe is lower than the opening. Thus, the water in the gap between the inner tube and the outer tube can flow into the inner tube through the opening. In addition, when the water surface inside the lowered inner pipe rises above the opening, the check valve closes, and the water inside the inner pipe passes between the inner pipe and the outer pipe through the opening. It is possible to block outflow into the gap. Thereby, a density difference can be ensured between the water inside the inner pipe and the water around the inner pipe, and the density of the water inside the inner pipe can be kept relatively high. . For this reason, even when new earth and sand is poured into the inner pipe after the earth and sand thrown into the inner pipe flows out of the pipe, the gap between the inner pipe and the outer pipe, Therefore, a circulating flow that circulates easily is easily generated, or the circulating flow is not interrupted, so that smooth earth and sand can be introduced. This circulation flow can also suppress the diffusion of pollution.

It is a longitudinal cross-sectional view which illustrates the double pipe tremy device of this invention. It is AA sectional drawing of FIG. It is a longitudinal cross-sectional view which illustrates the state which throws earth and sand into the double-pipe tremy device of FIG. 1, and the water surface of an inner pipe falls. It is a longitudinal cross-sectional view which illustrates the state which the water surface of an inner pipe rises after the state of FIG. FIG. 5 is a longitudinal sectional view illustrating a state in which earth and sand are thrown into the double-pipe tremy device after the state of FIG. 4 and the water surface of the inner pipe is lowered. It is a longitudinal cross-sectional view which shows the modification of the double pipe tremy device of this invention. It is a longitudinal cross-sectional view which illustrates the state which throws sand into the conventional double pipe tremy device, and the water surface of an inner pipe falls. It is a longitudinal cross-sectional view which illustrates the state which the water surface of an inner pipe rises after the state of FIG. It is a longitudinal cross-sectional view which illustrates the state of the water surface of the inner tube and the outer tube after the state of FIG.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A double-pipe tremy device and earth and sand loading method according to the present invention will be described below based on the embodiments shown in the drawings. In addition, the same code | symbol is used for the same component as the conventional double tube tremy apparatus 8. FIG.

  As illustrated in FIGS. 1 and 2, the double-tube tremy device 1 of the present invention has a double-tube structure in which an outer tube 2 is coaxially arranged on the outer peripheral side of the inner tube 3. The lower end of the inner tube 3 is located slightly above the lower end of the outer tube 2. An opening 4 is provided in the peripheral wall of the inner tube 3. The opening 4 is disposed such that the lower end thereof is equal to or lower than the water level outside the outer tube 2. Therefore, the opening 4 is in a state in which part of the opening 4 is submerged or in a state in which all of it is submerged with respect to the water level outside the outer tube 2.

  Water W flows into the opening 4 from the gap between the inner tube 3 and the outer tube 2 into the inner tube 3, and the water W flows from the inner tube 3 to the gap between the inner tube 3 and the outer tube 2. The check valve 6 which shuts out the outflow of is provided. A hopper 7 is provided at the upper end of the inner tube 3.

  In this embodiment, the inner pipe 3 and the outer pipe 2 are straight cylindrical steel pipes. The inner tube 3 and the outer tube 2 are not limited to a straight shape, and may have a shape in which the lower part has a larger diameter. In addition, the inner tube 3 and the outer tube 2 can be of both a stretchable type and a non-stretchable type. In the case of the expansion / contraction type, for example, a structure in which a plurality of tubular bodies are connected in a telescopic manner is used. In the case of the non-expandable type, a simple single pipe or a structure in which a plurality of pipes are added is used.

  For example, the inner tube 3 has an inner diameter of about 2 m to 5 m, an overall length of about 10 m to 25 m, and a wall thickness of about 10 mm to 15 mm. The outer tube 2 has, for example, an inner diameter of about 3 m to 6 m (about 1 m plus the inner diameter of the inner tube 3), a total length of about 11 m to 26 m (about 1 m of the total length of the inner tube 3), and a wall thickness of It is the same as the thickness of the tube 3 and is about 10 mm to 15 mm.

  All of the openings 4 have the same specifications (the same shape and the same size), and eight openings 4 are provided at equal intervals in the circumferential direction at the same height position of the inner tube 3. The size of the opening 4 is, for example, about 300 mm to 500 mm in width and about 1200 mm to 1800 mm in height.

  The openings 4 are not limited to be arranged uniformly in the circumferential direction, but a plurality of openings 4, preferably three or more openings 4 may be arranged at equal intervals in the circumferential direction. Each of the openings 4 can have different specifications, but by making the same specifications at the same height position, it becomes easy to obtain a stable and uniform circulation flow.

  The check valves 6 that open and close the respective openings 4 all have the same specifications, and are composed of a plate-like valve body 6a and a hinge member 6b provided at the upper end of the valve body 6a. The hinge member 6 b is fixed to the inner peripheral surface of the inner tube 3 at a position slightly above the upper end of the opening 4. The valve body 6 a is set so that the upper end is connected to the hinge member 6 b and the lower end is in a position slightly below the lower end of the opening 4 so as to contact the inner peripheral surface of the inner tube 3. The check valve 6 is not limited to the structure illustrated in this embodiment.

  In this embodiment, the cover 5 which covers the inner peripheral side of each check valve 6 is provided. The main function of the cover 5 is to protect the check valve 6 from the earth and sand S introduced into the inner pipe 3. When the earth and sand S are clogged in the hinge member 6b, the movable part around the hinge member 6b of the valve body 6a is hindered. Therefore, at least the hinge member 6b of the check valve 6 is covered by the cover 5.

  Each cover 5 has the same specification and is formed of a steel plate or the like. The upper end of the cover 5 is fixed to the inner peripheral surface of the inner tube 3 at a position slightly above the hinge member 6 b, and the lower end of the cover 5 extends to the same position as the lower end of the opening 4.

  The clearance between the cover 5 and the check valve 6 is set so as to ensure a movable space necessary when the check valve 6 is opened. When the check valve 6 is opened and the lower end of the valve body 6a moves toward the center of the inner tube 3, the lower end of the cover 5 is brought into contact with it and further movement is restricted. Therefore, the maximum valve opening angle of the check valve 6 (valve body 6a) can be changed depending on the position of the lower end of the cover 5.

  Therefore, a structure in which the position of the lower end of the cover 5 can be changed can also be used. For example, a structure in which the cover 5 can be expanded or contracted in the vertical direction, or a plurality of covers 5 having different lengths are made easy, and a structure that can be easily replaced with an arbitrary cover 5 is provided. With this structure, the maximum opening angle of the check valve 6 (valve element 6a) can be easily set to a desired angle by adjusting the position of the lower end of the cover 5 in accordance with the construction site and the properties of the earth and sand S. Can be.

  In order to make it hard to clog the earth and sand S thrown into the inner pipe 3, it is preferable to make the protrusion amount from the inner peripheral surface of the inner pipe 3 of the cover 5 small. When the cover 5 is not provided, it is preferable to reduce the amount of protrusion of the check valve 6 from the inner peripheral surface of the inner tube 3. For example, the whole or a part of the hinge member 6b is embedded in the wall surface of the inner pipe 3, so that the amount of protrusion of the check valve 6 from the inner peripheral surface of the inner pipe 3 is reduced, or the amount of protrusion is zero. Thus, the check valve 6 is set to the same level as the inner peripheral surface of the inner pipe 3.

  The check valve 6 can be provided not only on the inner peripheral surface of the inner tube 3 as illustrated in FIG. 1 but also on the outer peripheral surface of the inner tube 3 as illustrated in FIG. 6.

  The procedure of the earth and sand injection method of the present invention using the double tube tremy device 1 is as follows.

  First, the double-pipe tremey device 1 installed on a trolley or the like is placed in an upright state such that the lower ends of the inner pipe 3 and the outer pipe 2 are located in the vicinity of the water bottom in the water area into which the earth and sand S are introduced.

  Next, the earth and sand S scooped with the bucket using the backhoe is repeatedly put into the hopper 7. The earth and sand S thrown into the hopper 7 is thrown into the inner pipe 3. When the earth and sand S is thrown into the inner pipe 3, the density of the water W (mixed water with the earth and sand S) inside the inner pipe 3 becomes larger than the density of the surrounding water W, so that it is illustrated in FIG. In addition, the water level inside the inner pipe 3 is lowered.

  When the water surface inside the inner pipe 3 is lower than the opening 4, the valve body 6 a of the check valve 6 that closes the opening 4 causes the water W in the gap between the inner pipe 3 and the outer pipe 2 to flow. Pressure is pressed toward the center of the inner tube 3 to open the check valve 6, and water W in the gap between the inner tube 3 and the outer tube 2 flows into the inner tube 3 through the opening 4. At the lower ends of the inner tube 3 and the outer tube 2, the water W flowing out from the inner tube 3 diffuses, but a part of the water W flows into the gap between the inner tube 3 and the outer tube 2. As a result, a circulating flow that circulates between the gap between the inner tube 3 and the outer tube 2 and the inside of the inner tube 3 is generated.

  If new earth and sand S is thrown into the inner pipe 3 before the earth and sand S thrown into the inner pipe 3 flows out from the lower end of the inner pipe 3, this circulation flow will continue without interruption. The earth and sand S flowing out from the lower end of the inner pipe 3 accumulates on the bottom of the water in the lower position of the inner pipe 3.

  If the earth and sand S thrown into the inner pipe 3 flows out from the lower end of the inner pipe 3 and the new earth and sand S is left in place without being put into the inner pipe 3, The difference between the density of water W (mixed water with earth and sand S) and the density of W around the inner pipe 3 becomes small. Thereby, the water surface inside the inner pipe 3 that has been lowered rises as illustrated in FIG. 4 by reaction.

  In the present invention, when the water surface inside the inner pipe 3 that has been lower than the opening 4 rises above the opening 4, the valve body 6 a of the check valve 6 that opens the opening 4 rises. The check valve 6 is closed by being pressed toward the wall surface of the inner pipe 3 by the pressure of the water W inside the inner pipe 3. The water W inside the inner pipe 3 is blocked from flowing into the gap between the inner pipe 3 and the outer pipe 2 through the opening 4.

  Therefore, the water W inside the inner tube 3 and the water W in the gap between the inner tube 3 and the outer tube 2 vibrate up and down independently of each other. Since the outflow of water W from the inside of the inner pipe 3 to the gap between the inner pipe 3 and the outer pipe 2 is blocked, the density of the water W (mixed water with the earth and sand S) is rapidly increased by this vertical vibration. It will never be the same. A density difference can be ensured between the water W inside the inner pipe 3 and the water W around the inner pipe 3, and the density of the water W inside the inner pipe 3 can be kept relatively high. It becomes possible.

  Therefore, even after the earth and sand S introduced into the inner pipe 3 flows out from the lower end of the inner pipe 3, when the earth and sand S is introduced into the inner pipe 3, as illustrated in FIG. A circulating flow that circulates between the gap between the inner tube 3 and the outer tube 2 and the inside of the inner tube 3 is generated quickly, or the circulating flow is not interrupted and the earth and sand S can be smoothly poured into the bottom of the water. It becomes possible. Moreover, the spreading | diffusion of the pollution produced by the thrown-in earth and sand S can also be suppressed with the circulating flow to generate | occur | produce.

  That is, even when the new earth and sand S cannot be thrown into the inner pipe 3 before the earth and sand S thrown into the inner pipe 3 flows out from the lower end of the inner pipe 3, the earth and sand S is smoothly thrown into the bottom of the water. It is possible to suppress the diffusion of pollution. Therefore, when the time until the earth and sand S thrown into the inner pipe 3 flows out of the pipe is short, for example, even when the water depth to the bottom into which the earth and sand S is thrown is 5 to 15 m, the circulating flow is quickly generated. Alternatively, the circulation flow is not interrupted, and the smooth sediment S can be introduced and the diffusion of the contamination can be suppressed. Further, when the time interval at which the earth and sand S is thrown becomes longer, for example, even when the earth and sand S is repeatedly thrown into the double pipe tremy device 1 (inner pipe 3) using a backhoe bucket, Is generated quickly, or the circulation flow is not interrupted, and smooth introduction of the earth and sand S and suppression of the diffusion of contamination can be achieved.

  It is most preferable if the passage of the water W can be completely blocked when the opening 4 is closed by the check valve 6, but it is far more than the prior art in which the check valve 6 is not provided even if some blocking leakage occurs. Therefore, it is possible to smoothly introduce earth and sand S and to suppress the diffusion of pollution.

  As described above, the earth and sand S can be efficiently deposited in a predetermined range of the bottom of the water by using the circulating flow by repeatedly introducing the earth and sand S using the double pipe tremy device 1. The inner pipe 3 and the outer pipe 2 are gradually moved upward according to the height of sediment S on the bottom of the water.

  The present invention can be applied, for example, when the depth of water up to the bottom of the soil S is 5 m to 30 m. In addition, this invention is applicable not only when throwing earth and sand S into the inner pipe 3 using the bucket of a backhoe, but also when throwing earth and sand S using a belt conveyor etc. When using a belt conveyor or the like, since the earth and sand S can be continuously put into the inner pipe 3, the circulation flow is continuously generated without difficulty. However, when the operation of the belt conveyor is temporarily stopped, When the earth and sand S cannot be supplied onto the conveyor without interruption, new earth and sand S is introduced into the inner pipe 3 before the earth and sand S introduced into the inner pipe 3 flows out from the lower end of the inner pipe 3. I can't. By applying the present invention in such a case, the earth and sand S can be smoothly poured into the bottom of the water, and the diffusion of pollution can be suppressed.

DESCRIPTION OF SYMBOLS 1 Double pipe treme device 2 Outer pipe 3 Inner pipe 4 Opening part 5 Cover 6 Check valve 6a Valve body 6b Hinge member 7 Hopper 8 Conventional double pipe treme device S Earth and sand

Claims (5)

  In the double tube tremy device having an outer tube disposed on the outer peripheral side of the inner tube and having an opening on the peripheral wall of the inner tube, the opening is disposed such that the lower end thereof is equal to or lower than the water level outside the outer tube, A check valve is provided in the opening to allow water to flow from the gap between the inner pipe and the outer pipe into the inner pipe, and from the inside of the inner pipe to the gap between the inner pipe and the outer pipe. Double tube tremy device provided.   The double pipe tremy device according to claim 1, further comprising a cover that covers an inner peripheral side of the check valve.   The said check valve is comprised by the plate-shaped valve body and the hinge member provided in the upper end part of the valve body, The said cover WHEREIN: At least a hinge member is covered among the check valves. Double tube tremy equipment.   In the earth and sand charging method, the outer pipe is disposed on the outer peripheral side of the inner pipe, and the double-pipe tremy device having an opening on the peripheral wall of the inner pipe is used to put the earth and sand into a predetermined range of the water bottom through the inner pipe. The opening is arranged so that its lower end is below the water level outside the outer pipe, a check valve is provided in this opening, the earth and sand are poured into the inner pipe, and the water surface inside the inner pipe is When lower than the opening, the check valve closing the opening is opened, and water in the gap between the inner pipe and the outer pipe flows into the inner pipe through the opening. When the water level inside the lowered inner pipe rises above the opening, the check valve closes, and the water inside the inner pipe flows into the gap between the inner pipe and the outer pipe through the opening. The method of throwing in the earth and sand to block.   The method according to claim 4, wherein the earth and sand are repeatedly introduced into the inner pipe using a bucket of a backhoe.