JP4602840B2 - Method of forming a calm water area for work - Google Patents

Description

  The present invention relates to a method for forming a working calm water area for a diver to perform work in running water such as the ocean, a river, and a canal.

  Conventionally, when a diver performs an operation under running water, there is a case in which the underwater operation of the diver may be hindered because there is a flow velocity in the underwater work area. In general, the critical flow velocity at which a diver can work while diving is set to 0.5 m / sec to 1.0 m / sec.

And when there is a daily fluctuation or a seasonal fluctuation in the flow velocity of the flowing water, a time zone or a season with a low flow velocity is selected as the work period. Further, when the flow velocity of the water flow is always high, a method is adopted in which the work area is closed, the water inside the cut-off is excluded, and a dry work space is secured (see, for example, Patent Document 1).
JP 11-21908 A

  However, if the work process is adjusted to the daily fluctuation and seasonal fluctuation of the flow velocity of the running water, the work time zone and the period are limited and work efficiency is deteriorated. Furthermore, if the flow rate fluctuates due to the weather, the work process cannot be determined and the work may be delayed.

  When the work area is closed, there is no restriction on the construction period, but it is necessary to make the structure resistant to hydrostatic pressure in order to dry the work area. For this reason, the structure must be connected in a circumferential vertical direction using a special panel, or the double deadline method must be used. As the construction period becomes longer, the construction cost will increase.

  An object of the present invention is to enable a diver to work efficiently in running water without making the working area dry and without being affected by the flow velocity of the flowing water around the working area.

  In order to solve the above-described problems, the working calm water area forming method according to the first aspect of the present invention is, as shown in FIGS. 1 to 3, for example, an underwater work area 1 in which a diver 12 works in running water. A flow rate control work 2 having a gap 11 through which flowing water can pass is disposed in a predetermined range around the water to reduce the flow rate of flowing water in the underwater work area 1.

  In this way, the flow velocity control worker 2 has a gap 11 through which flowing water can pass and becomes resistance of flowing water, reduces the flow velocity of flowing water in the underwater work area 1, and forms a working calm water area where the diver 12 can work. can do. Thereby, the diver 12 can work efficiently without being influenced by the flow speed of the surrounding water in the calm water area for work in which the flow speed of the flowing water is reduced. Moreover, since the flow velocity control work 2 can pass flowing water, it does not need to be a structure which resists a hydrostatic pressure, and is not large-scale like the conventional temporary installation.

  In addition, the said predetermined range which arrange | positions the flow velocity control worker 2 can be suitably set according to the condition of a work area. For example, you may arrange | position continuously over the perimeter of the circumference | surroundings of a working area, and may arrange | position partially. Further, when the direction of running water is constant, it may be installed in a range in front of at least the running water direction around the work area. Even if the direction of running water changes, if the flow velocity in a specific direction is large and it is certain that the flow velocity in other directions does not affect the work of the diver 12, at least in the flowing water direction with a large flow velocity. On the other hand, you may make it install in the front range.

Furthermore, the method of forming the working quiet waters according to claim 1, for example, as shown in FIGS. 2 and 3, and placing the predetermined range in a frame assembled to the stereoscopic lattice form (steel frame 3), the A plurality of baskets (stone-packed baskets 10) packed with a filling material (stone 10c) so as to have the gap 11 in the frame are built to form the flow rate control work 2.

  In this way, the flow rate control worker 2 has a simple structure in which a frame assembled in a three-dimensional lattice shape is installed and a plurality of baskets packed with filling materials are built in the frame. . Therefore, the arrangement work of the flow velocity control worker 2 can be facilitated, and the construction cost can be reduced.

The invention according to claim 2 is the method of forming the working calm water area according to claim 1 , for example, as shown in FIGS. 2 and 3, in the predetermined section of the frame (steel frame 3). The water stop plate 7 is attached in a watertight manner so as to surround the frame, and buoyancy is imparted when the frame is installed.

  In this way, by providing buoyancy to a predetermined section of the frame, it is possible to save labor for the frame transportation work and installation work. The predetermined section is desirably set at a position where the balance of buoyancy with respect to the frame is appropriate in accordance with the shape and weight of the frame.

Invention of Claim 3 is the formation method of the calm water area for work of Claim 1 or 2 , for example, as shown in FIG.2, 3, the said filling material (stone 10c) is a cobblestone or a crushed stone. It is characterized by being.

  Thus, by using cobblestone and crushed stone, which are natural materials, as the filling material, the flow rate control work 2 can be formed at low cost.

  According to the present invention, the flow velocity of the flowing water in the underwater work area is set by disposing a flow rate controller having a gap through which the water can pass in a predetermined range around the underwater work area where the diver works in flowing water. A working calm water area that can be reduced and can be used by divers is formed. And the diver can work efficiently in the calm water area for work without being affected by the flow velocity of the flowing water. Further, since the flow rate control worker does not resist the hydrostatic pressure, it is not necessary to make it large as in the prior art.

  Furthermore, the flow rate control worker can be formed by installing a frame assembled in a three-dimensional lattice shape and laying a plurality of baskets filled with filling material so as to have a gap in the frame. Alternatively, it can be formed by installing a frame assembled in a three-dimensional lattice shape and having a net attached to the outer peripheral surface thereof, and introducing a filling material so as to have a gap inside the frame surrounded by the net. . Thus, since the structure of the flow rate control work is simple, it can be easily arranged and can be constructed at low cost.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 to 26, in the present embodiment, the present invention is applied to a seismic reinforcement work for a bridge pier 21 that is an underwater structure in a bridge constructed in a strait.

  As shown in FIGS. 2 and 3, the bridge is a road bridge, and is composed of an upper structure 20 (partially shown), a bridge pier 21 that supports the upper structure 20 and a foundation 22 that is integrally formed at the lower end thereof. And. The upper part of the pier 21 is on the sea and the lower part is in the sea. The lower end of the foundation 22 is buried in the seabed ground. The horizontal cross-sectional shape of the pier 21 and the foundation 22 is an oval shape, and the pier 21 is slightly smaller than the foundation 22.

  In the seismic reinforcement work for the bridge pier 21 that is an underwater structure, the diver 12 works in the vicinity of the outer peripheral surface of the underwater portion of the pier 21 (hereinafter referred to as the underwater work area 1) under running water. The maximum flow velocity of the tidal current is 3 m / second, which exceeds the limit of diving work of the diver 12 as it is.

  Therefore, in the present embodiment, in order to reduce the flow velocity of the flowing water in the underwater work area 1 and form a calm water area for work, the flow rate control worker 2 is disposed around the underwater work area 1. The flow rate control work 2 is arranged so as to surround the pier 21 at a predetermined interval from the outer peripheral surface of the pier 21 continuously along the outer peripheral surface of the pier 21 over the entire periphery.

  First, the configuration of the flow rate control worker 2 will be described. As shown in FIGS. 2 and 3, the flow rate control worker 2 is generally configured by a steel frame 3 assembled in a three-dimensional lattice shape and a stone-packed basket 10 built in the steel frame 3.

  As shown in FIG. 4, the steel frame 3 has an oval shape whose horizontal cross section is substantially similar to the pier 21 and the foundation 22 and is slightly smaller than the foundation 22. When the height of the steel frame 3 is set on the foundation 22, the upper part of the steel frame 3 is H. W. It is set to be higher than L.

  In the present embodiment, the steel frame 3 is divided into four U-shaped portions 4 and linear portions 5 facing each other along the outer peripheral direction of the pier 21. The U-shaped part 4 is assembled in a three-dimensional lattice shape using H-shaped steel columns 4a and beams 4b, respectively, and has a plurality of sections surrounded by the columns 4a and beams 4b. Similarly, the straight portion 5 is assembled in a three-dimensional lattice shape by the pillars 5a and the beams 5b.

  In order to give buoyancy to the predetermined section of the steel frame 3 when installing the steel frame 3, as shown in FIG. 5, a water stop plate 7 is attached in a watertight manner so as to surround the section. It has been. In the present embodiment, as shown in FIG. 4, as the mounting section of the water stop plate 7 (hereinafter referred to as the buoyancy section 6), the U-shaped section 4 has straight sections in the vertical sections of both ends and the middle section. In the part 5, the longitudinal sections at both ends are set to positions where the balance of buoyancy with respect to the steel frame 3 is appropriate.

  With this buoyancy part 6, buoyancy is generated with respect to the steel frame 3, and buoyancy can be adjusted by pouring water into the buoyancy part 6 as necessary. Thereby, the labor and installation work of the steel frame 3 in water can be saved.

  As shown in FIG. 5 (a), the waterstop 7 is attached to the surface parallel to the outer peripheral direction of the pier 21 with bolts 8 and the steel plate 7a to the surface parallel to the separating direction from the pier 21. Are performed by welding. The water stop plate 7 to be joined with the bolt 8 has a plurality of bolt holes 7b formed at predetermined intervals along the outer peripheral edge. A hole through which the bolt 8 is inserted is formed in the steel frame 3 at a position corresponding to the bolt hole 7b. Further, as shown in FIG. 5B, when the waterproof packing 7c is continuously provided along the outer peripheral edge inside the bolt hole 7b, and the water stop plate 7 is fastened to the steel frame 3 with the bolts 8. Pressed to make it watertight. The iron plate 7a is reinforced with angle steel as reinforcing material 7d at predetermined intervals in the vertical and horizontal directions. The water stop plate 7 can be detached from the steel frame 3 after the steel frame 3 is installed, and the stone-packed basket 10 can be built therein.

  As shown in FIG. 6, the stone-packed basket 10 is welded with a metal mesh 10b, an expanded metal, etc., to each surface of a frame 10a assembled into a cube with angle steel, and the stone 10c (filling material) is packed in the inside. It is a thing. Further, a gap 11 is formed between the packed stones 10c so as to have a predetermined porosity. The external shape of the stone-packed basket 10 is a shape corresponding to the section of the steel frame 3 in which the stone-packed basket 10 is arranged, and can be inserted into each section from above. The stone 10c to be packed is a natural cobblestone, crushed stone, or the like, and the flow rate control worker 2 can be formed at low cost.

  Here, the steel frame 3, for example, the straight portion 5, serves as a guide member 9 that guides when a stone-packed basket 10 is inserted into the four corners of each section surrounded by the beam 5 b in plan view. Angle steel is provided in the vertical direction.

  Next, based on FIGS. 9 to 26, the procedure for reinforcing the pier 21 and the procedure for forming a working calm water area will be described using the flow rate control worker 2 configured as described above.

  First, as shown in FIG. 9, as preparation for reinforcement work of the pier 21, a plurality of hoist rail brackets 30 for installing hoist 41 described later are fixed to the upper surface of the pier 21 at predetermined intervals in the longitudinal direction. Install. The hoist rail bracket 30 slightly protrudes from both side surfaces of the upper portion of the pier 21. In addition, a temporary stage 31 is assembled on the pier 21 as a place for materials and equipment by assembling a single pipe scaffold or the like. The materials and equipment necessary for these brackets, temporary stage 31 and the like are suspended from a bridge road by a rough terrain crane (not shown).

  Next, as shown in FIG. 10, an underwater platform 33 for placing the flow velocity control worker 2 on the foundation 22 is installed. The underwater platform 33 is installed by hanging the underwater platform 33 with a trolley with a crane (not shown) and fixing it with an underwater anchor 34 by the diver 12. The diver 12 performs the work by supplying air with a hose from the submersible compressor 32 installed on the temporary stage 31.

  Then, as shown in FIG. 11, the steel frame 3 is transported to the vicinity of the pier 21 by a hoist ship (not shown), and the hoist ship is temporarily moored near the pier 21 and then suspended and suspended in the sea. A winch 35 is installed on the upper part of the pier 21, a pulley 36 is installed on the upper part of the foundation 22, one end of the wire 37 is fixed to the steel frame 3, and the other end side of the wire 37 is wound up by operating the winch 35, The steel frame 3 is moved.

  At this time, seawater is injected into the buoyancy part 6 of the steel frame 3 to adjust the buoyancy with respect to the steel frame 3, and the diver 12 guides the steel frame 3 and lowers it toward the underwater platform 33. Deploy. These operations are performed for each of the U-shaped portion 4 and the straight portion 5 of the steel frame 3, arranged so as to surround the underwater work area 1, and fixed on the underwater platform 33. In addition, after fixing the steel frame 3 to the underwater frame 33, the diver 12 removes the water stop plate 7 from the steel frame 3.

  After installing the steel frame 3, as shown in FIG. 12, the stone-packed basket 10 is transported to the vicinity of the pier 21 by a trolley with a crane, and the guide member 9 is inserted into the respective sections from above the steel frame 3. It is lowered and built while guiding. When the installation of all the stone-packed baskets 10 is completed, the flow velocity control worker 2 is completed.

  The underwater platform 33, the steel frame 3, the stone-packed basket 10, and the like are manufactured in advance in a production yard on the ground. Simultaneously with these transports, temporary steel materials and the like necessary for the subsequent work are transported and unloaded onto the steel frame 3.

  After the flow rate control work 2 is completed, the reinforcement work for the pier 21 is started. As preparation, first, as shown in FIG. 13, a single pipe scaffold is assembled on the steel frame 3 and a work scaffold 38 is installed. The steel frame 3 is also used as a work gantry. The hoist rails 42 are fixed to the hoist rail brackets 30 on both sides of the upper portion of the bridge pier 21 along the longitudinal direction using the temporary steel material unloaded from the work scaffold 38 to the steel frame 3. A plurality of hoists 41 are suspended from the rail 42.

  After the hoist 41 is installed, the work scaffold 38 on the steel frame 3 is disassembled and removed. Further, as shown in FIG. 14, a surface treatment compressor 32 is installed on the temporary stage 31, and the diver 12 performs the surface treatment (keren work) on the outer peripheral surface of the pier 21.

  Next, as shown in FIG. 15, a plurality of axial rebars 44 are installed at predetermined intervals in the vertical direction along the outer peripheral surface of the pier 21 by the diver 12. The axial rebar 44 is carried from the float carrier 46. The axial rebar 44 is built by cutting the fixing hole 45 on the upper surface of the foundation 22, roughening the inside of the fixing hole 45, filling with a fixing agent (water curable), and lower end of the axial rebar 44. This is done by inserting a part.

  After the construction of the axial rebar 44 is completed, as shown in FIG. 16, the temporary assembly bracket 49 of the precast panel 47 is installed near the upper part of the axial rebar 44 built over the outer peripheral surface of the bridge pier 21. . Then, the first precast panel 47 is carried in from the float carrier 46 and assembled in a ring shape on the temporary assembly bracket 49. The first-stage precast panel 47 assembled in a ring shape is suspended using a lifting jig. A level adjusting bolt 8 is previously installed on the foundation 22.

  As shown in FIG. 18, after the first-stage precast panel 47 is installed, before the concrete 50 is filled between the pier 21 and the precast panel 47, the diver 12 attaches the anchoring anchor 48 to the precast panel 47. The precast panel 47 is fixed to the pier 21 by driving in the circumferential direction. Further, in order to prevent leakage of the concrete 50 to be filled, the concrete is placed on the outside of the first stage precast panel 47 with the underwater frame 33 as the mold 10a.

  Next, as shown in FIG. 19, concrete 50 is filled between the pier 21 and the precast panel 47. The concrete 50 is underwater non-separable concrete. The casting height of the concrete 50 is a height that is 30 cm lower than the top end of the precast panel 47. The concrete 50 is placed by placing a small concrete pump truck (not shown) on the bridge road and relaying the relay pump 51 on the temporary stage 31 so that the diver 12 pumps it to the placement site. This is done by moving the hose 52.

  As shown in FIG. 20, the precast panels 47 in the second and subsequent stages are constructed by repeating the assembly, installation work, and concrete 50 filling work described above. As shown in FIG. 21, the uppermost precast panel 47 is assembled while the precast panels 47 are directly installed one by one after the temporary assembly bracket 49 is removed.

  An adhesive is applied in advance to the bottom surface of each precast panel 47. Further, as shown in FIG. 22, the top end of the precast panel 47 is finished using a polymer cement mortar from a mortar mixer 53 installed on the temporary stage 31. As described above, the reinforcement of the pier 21 is performed.

  Then, as shown in FIG. 23, the hoist rail 42, the temporary stage 31, the flow velocity control worker 2 and the like are removed. A single pipe scaffold is again installed on the steel frame 3, the hoist rail 42 is disassembled, and the hoist rail 42 is lifted and removed by a rough terrain crane (not shown) installed on the bridge road. Thereafter, the hoist rail bracket 30 and the work scaffold 38 are removed.

  As shown in FIG. 24, the stone-packed basket 10 built in the steel frame 3 is extracted and collected by a trolley with a crane. After removing the stone-packed cage 10, as shown in FIG. 25, the water stop plate 7 is attached to the steel frame 3 again by the diver 12 to form the buoyancy portion 6 surrounded by the water stop plate 7. The fixation of the steel frame 3 to the underwater gantry 33 is released, and the submersible pump is inserted into the buoyancy unit 6 to perform drainage, thereby floating the steel frame 3. The steel frame 3 is moved to the vicinity of a moored hoist ship (not shown) by operating the winch 35, the wire 37 is replaced on the hoist ship side, and it is hung on the ship and transported.

  As shown in FIG. 26, all the temporary materials on the underwater gantry 33 and the pier 21 are removed, and all the construction is completed.

  According to the present embodiment, the flow rate control worker 2 has the gap 11 between the stones 10c packed in the stone-packed basket 10, resistance occurs in the flowing water, and the flow velocity of the flowing water in the underwater work area 1 is set. Can be reduced. Thereby, the underwater work area | region 1 can be formed as a calm water area for work where the diver 12 can work around the pier 21. In the reinforcement work of the pier 21, the diver 12 works to install the axial rebar 44 and the precast panel 47 without being affected by the flow speed of the surrounding water in the quiet working area where the flow speed of the flowing water is reduced. Can be performed efficiently.

  Moreover, since the flow velocity control work 2 can pass flowing water, it does not need to be a structure which resists a hydrostatic pressure, and is not large-scale like the conventional temporary installation. Further, the flow rate control worker 2 has a simple structure in which a steel frame 3 assembled in a three-dimensional lattice shape is installed and a plurality of stone-packed baskets 10 are built in the steel frame 3. Therefore, the steel frame 3 and the stone-packed basket 1010 can be installed in a short time, the flow rate control worker 2 can be easily formed, and the cost can be reduced.

  In the above embodiment, the present invention is applied to the reinforcement work of the pier 21. However, the present invention is not limited to this, and can be applied to other underwater work by a diver. And in this Embodiment, although the arrangement | positioning of the flow velocity control worker 2 was continuously performed over the outer periphery so that the bridge pier 21 might be surrounded, this invention is not limited to this, According to the condition of a work area Can be set as appropriate. For example, you may arrange | position continuously over the perimeter of the circumference | surroundings of a working area, and may arrange | position partially. Further, when the direction of running water is constant, it may be installed in a range in front of at least the running water direction around the work area. Even if the direction of running water changes, if the flow velocity in a specific direction is large and it is certain that the flow velocity in other directions does not affect the work of the diver 12, at least in the flowing water direction with a large flow velocity. On the other hand, you may make it install in the front range.

  In addition, as a method of forming a flow rate control worker, a steel frame was installed and a stone-clad basket was built in the steel frame, but a steel frame with a wire mesh attached to the outer peripheral surface was installed. It is also possible to throw stones into the interior of the steel frame surrounded by the wire mesh. In this case, when removing the flow rate control work, it is possible to remove the wire mesh, discharge the stone to the bottom of the water, and save labor for removing the steel frame.

  Further, although stone 10c such as cobblestone and crushed stone is used as the filling material, blocks, timber, plastic bottles, etc. are also possible, and it is of course possible to change the specific details of the structure as appropriate. is there.

  Here, the present inventors conducted a fluid analysis for the purpose of quantitatively grasping the flow velocity reduction effect by the flow velocity controller. The analysis was a three-dimensional free surface analysis using the VOF method, and general-purpose thermal fluid analysis software was used.

  First, modeling of the flow rate control work (porous model) will be described. In general, the resistance of granular permeable materials such as stones and deformed blocks to flow can be expressed in the form of a loss head as shown below (Dupui Forchheimer's law). Therefore, in modeling the flow rate control process, a pressure loss condition using a resistance coefficient obtained by the following equation is added to the flow rate control process.

  In this analysis, the terrain change around the pier was ignored, and the water level was H.264. W. L. +3.0 m. The tidal current was a uniform flow, and a unit flow rate of 1.0 m / sec was given. In addition, a range of 1.5 m from the outer peripheral surface of the pier is set as an underwater work area, and a flow velocity control worker having a width of 1.5 m is arranged on the outer periphery. The width of the flow rate control work is 1.5 m. W. L. It was decided to pack all the stones. The main analysis conditions are shown in the table below.

  FIG. 27 is an arrangement of flow rate reduction rates at various positions in the underwater work area around the pier, using the clogging porosity as a parameter. Here, the flow rate reduction rate indicates the ratio of the flow rate to the type without the flow rate control process. Moreover, as a measurement position of a flow velocity, they are the front of a bridge pier, diagonally forward, a side surface, and diagonally backward. As shown in FIG. 27, it can be seen that when the porosity of the cobblestone is 50% or less, the flow velocity reduction rate can be suppressed to about 0.18 or less at any position.

  From the above examination results, even at strong tide of 3.0 m / sec, it is possible to keep the flow velocity to about 0.5 m / sec or less in the underwater work area surrounded by the flow velocity control work. It was shown that the working environment can be maintained substantially within the working critical flow velocity of 0.5 m / sec.

It is a perspective view which shows the formation method of the working calm water area in one embodiment to which this invention is applied. It is sectional drawing which shows the structure of the flow velocity control construction same as the above. It is a top view which shows the structure of a flow velocity control work same as the above. It is a plane sectional view showing the composition of a steel frame. It is a top view which shows attachment of a water stop board same as the above. FIG. 2 is a plan sectional view of the structure of the water stop plate. It is a side surface, a plane, and sectional view showing the composition of a stone stuffing basket. It is the top view explaining the erection of the stone stuffing basket in the steel frame. It is a figure explaining installation work, such as a temporary stage, in the construction procedure of the reinforcement work of a bridge pier. It is a figure explaining the installation work of the underwater frame for installing a steel frame. It is a figure for demonstrating the installation operation | work of a steel frame. It is a figure explaining the erection operation | work of the stone stuffing basket in a steel frame. It is a figure explaining the installation work of a hoist rail same as the above. It is a figure explaining the surface treatment work of a bridge pier same as the above. It is a figure explaining the installation work of an axial rebar similarly. It is a figure explaining the temporary assembly work of a precast panel similarly. It is a figure explaining the installation work of a precast panel similarly. It is a figure explaining the driving | operation operation | work of the locking anchor to a precast panel similarly. It is a figure explaining the filling operation | work of concrete same as the above. It is a figure explaining the installation operation | work of the precast panel of the 2nd step | stage after the same. It is a figure explaining the installation work of the uppermost precast panel. It is a figure explaining the finishing operation | work of a precast panel top end. It is a figure explaining the removal operation | work of a hoist same as the above. It is a figure explaining the removal work of a stone stuffing basket same as the above. It is a figure explaining the removal operation | work of a steel frame. It is a figure explaining the situation where the reinforcement work of the bridge pier was completed. It is a graph showing the influence of the porosity of the packing stone to the flow velocity reduction rate as a fluid analysis result.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Underwater work area | region 2 Flow velocity control work 3 Steel frame 4 U-shaped part 5 Linear part 4a, 5a Column 4b, 5b Beam 6 Buoyancy part 7 Water stop plate 7a Iron plate 7b Bolt hole 7c Waterproof packing 7d Reinforcement material 8 Bolt 9 Guide member 10 Stone-filled basket 10a Frame 10b Wire net 10c Stone (medium filling material)
DESCRIPTION OF SYMBOLS 11 Cavity 12 Diver 20 Superstructure 21 Bridge pier 22 Foundation 30 Hoist bracket 31 Temporary stage 32 Submersible compressor 33 Submersible mount 34 Underwater anchor 35 Winch 36 Pulley 37 Wire 38, 39, 40 Work scaffold 41 Hoist 42 Hoist rail 43 Surface treatment Compressor 44 Axial rebar 45 Fixing hole 46 Float carrier 47 Precast panel 48 Anchor anchor 49 Temporary bracket 50 Concrete 51 Relay pump 52 Pressure hose 53 Mortar mixer

Claims (3)

A frame assembled in a three-dimensional grid is installed in a predetermined area around the underwater work area where divers work in running water, and the filling material is packed so that there is a gap through which running water can pass. A method for forming a calm water area for working, wherein a plurality of baskets are built and a flow rate control work is arranged to reduce the flow speed of running water in the underwater work area. To a predetermined section of said frame, attach the waterstop so as to surround the compartment watertight, working quiet waters according to claim 1, characterized in that to provide buoyancy when installing the frame Forming method. Wherein during filling material, forming method of working quiet waters according to claim 1 or 2, characterized in that a cobblestone or crushed stone.

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