JP2018076661A - Device, structure and method to prevent self-sinking of steel pipe pile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scuttling prevention device for steel pipe piles, a scuttling prevention structure and a scuttling prevention method capable of shortening the construction time of the entire offshore construction including the construction of a root-hardening type steel pipe pile and reducing the material construction cost. SOLUTION: A steel pipe pile self-sinking prevention device 1 to which the present invention is applied prevents the steel pipe pile 8 from self-sinking, and includes a floating body portion 2 that floats in seawater and is connected to the steel pipe pile 8. In the portion 2, the lower end portion 8u of the steel pipe pile 8 provided in the root compaction portion 81 filled with the fluid solidifying material in the seabed ground 9 is separated from the bottom surface portion 81u of the root compaction portion 81. It is characterized in that the buoyancy force is transmitted to the steel pipe pile 8 to be connected to hold the position of the steel pipe pile 8. [Selection diagram] Fig. 1

Description

  The present invention relates to a steel pipe pile self-sink prevention device, a self-sink prevention structure, and a self-sink prevention method.

  Conventionally, for the purpose of improving workability when constructing steel pipe piles in onshore construction, for example, methods for constructing steel pipe concrete frame columns disclosed in Patent Documents 1 to 3 have been proposed. Moreover, in order to improve the workability at the time of constructing a steel pipe pile etc. in the offshore construction, the well formation steel pipe sheet pile aggregate etc. which were disclosed by patent documents 4 and 5 are proposed, for example.

  In the construction method of a steel pipe concrete frame column disclosed in Patent Document 1, a guide pipe is vertically suspended in a pile hole in which concrete of a cast-in-place reinforced concrete foundation pile is placed in a lower portion, and a bottom plate is attached in the guide pipe. The hollow steel pipe column is inserted, the concrete is poured into the hollow steel pipe column, the hollow steel pipe column is lowered into the guide pipe, and finally the lower end of the steel pipe column is uncured by the dead weight of the hollow steel pipe column filled with concrete. After stabilization of the foundation pile concrete and the filled concrete of the hollow steel pipe column, subsidize it in the foundation pile concrete, remove the guide pipe etc. A steel pipe concrete column is constructed by filling the soil mortar.

  A method of vertically installing a pile in a building structure using a pile disclosed in Patent Document 2 as a pillar and a jig used in the method assemble a base frame around an excavation hole. The pile support and the fixing plate divided into four divided pieces are placed on the base frame. Each divided piece can slide in the radial direction, whereby the pile support and the pile through-hole in the center of the fixed plate are expanded and contracted. In addition, a standing frame is erected on each of the four main frames of the base frame. An arm is horizontally provided at the upper end of the standing frame, and the tip of the arm is as close as possible to the pile to form a pile support portion. Furthermore, a pile pushing device is disposed on the lower surface of each arm.

  The steel pipe structure column construction method disclosed in Patent Document 3 has a length equivalent to or substantially equal to the bottomed steel pipe column inside the bottomed steel pipe column with the base plate placed on the foundation pile as the bottom wall. The CFT steel pipe column is constructed by allowing the sleeve pipe of the CFT to stand in a watertight manner from an appropriate position of the base plate, and the lower end of the sleeve pipe is opened by a through hole drilled in the base plate. After being built in the pile hole into which pile is injected, pile concrete is placed in the lower part of the pile hole through the sleeve pipe, and then the CFT filled concrete is placed in the CFT steel pipe column and the space in the sleeve pipe. To cast.

  The well-forming steel pipe sheet pile assembly disclosed in Patent Document 4 and its installation method are used to close a plurality of steel pipe sheet piles outside the construction site to create a steel pipe sheet pile assembly, and to construct the steel pipe sheet pile assembly as a floating body. Move to a location, sink the steel pipe sheet pile assembly on the bottom of the predetermined area, adjust the vertical accuracy of the steel pipe sheet pile assembly, if necessary, one steel pipe sheet pile of the steel pipe sheet pile assembly Drive into the ground one by one.

  The construction method of a pile-type offshore structure and the pile-type offshore structure disclosed in Patent Document 5 include a spud inserted into leg wells formed at the four corners of the frame, and a plurality of pile driving holes therebetween. Form. The bottom of the hole for pile driving is sealed with a diaphragm. In the construction method of an offshore structure, a step of towing a chassis provided with a leg well fitted with a spud and a hole for placing a pile to a predetermined position on the sea and supporting the spud on the sea The process of raising the housing to a height position that is not affected by waves above the sea surface by lowering it by placing it on the seabed, and injecting ballast water into the container in the housing at this position to reduce the weight of the housing A step of increasing and a step of driving the pile deeper than the spud through the hole for driving the pile provided in the frame and fixing the pile to the frame.

JP-A-4-281915 Japanese Patent Laid-Open No. 10-140564 JP 2004-162370 A JP 2005-146671 A JP 2013-204399 A

  Here, as a method for placing the steel pipe pile, there is a consolidation method for solidifying a fluidized solidifying material (for example, cement milk) around the lower end portion of the steel pipe pile. However, when the rooting construction method is used in offshore construction, it is necessary to prevent self-settling of the steel pipe pile until the fluidized solidified material is consolidated (for example, about 1 to 2 days). As a measure to prevent this self-sink, there is a method of fixing steel pipe piles using guide piles and guide frames as temporary materials. In this method, the guide piles are placed on the seabed ground and protruded from the sea of the guide piles. A process of removing the guide frame and the guide pile occurs after the guide frame is attached to the portion where the guide frame is attached in the horizontal direction by welding or bolt joining, and the fluidized solidified material of the solidified portion of the steel pipe pile is solidified. Moreover, since the weight of the steel pipe pile increases as the steel pipe pile becomes larger and longer, it is necessary to increase the size of the guide frame and the guide pile or reduce the number of steel pipe piles supported by one guide pile. . Such a process related to the lead pile and lead frame causes an increase in the construction period of the entire offshore construction including construction related to the placement of steel pipe piles, and therefore, an increase in material construction costs consisting of material costs and construction costs becomes an issue. Yes.

  And the method disclosed by patent documents 1-3 is an indication of the technique regarding the construction on land, and is not disclosed about the self-sediment prevention of the steel pipe pile in the offshore construction where work is difficult compared with land construction. In the methods disclosed in Patent Documents 4 and 5, a steel pipe sheet pile assembly or a pile is directly placed on the seabed, and the self-sinking of the steel pipe pile in the consolidation method is not disclosed. In addition, in the methods disclosed in Patent Documents 4 and 5, in order to place large frame support piles or spuds on the seabed, if used as a measure to prevent self-sinking of steel pipe piles, the construction period is the same as described above. The prolongation and increase in material construction costs are issues.

  Therefore, the present invention has been devised in view of the above-described problems, and the object of the present invention is to shorten the construction period of the entire offshore construction including construction of a solidified steel pipe pile and material costs. An object of the present invention is to provide a self-sediment prevention device, a self-sediment prevention structure, and a self-sediment prevention method for steel pipe piles that can realize a reduction in the amount of steel.

  A steel pipe pile self-sink prevention device according to a first aspect of the present invention is a steel pipe pile self-sink prevention device for preventing the steel pipe pile self-sink, and includes a floating body part that floats in seawater and is connected to the steel pipe pile, In the state where the lower end portion of the steel pipe pile provided in the root consolidation portion filled with the fluidized solidified material in the seabed ground is separated from the bottom surface portion of the root consolidation portion, buoyancy is exerted on the steel pipe pile to be connected. It is transmitted and the position of the said steel pipe pile is hold | maintained, It is characterized by the above-mentioned.

  The self-sediment prevention device for steel pipe piles according to a second aspect of the present invention is the first aspect of the invention, further comprising one or a plurality of restraint members connected to the floating body part and anchors placed in the seabed ground, The tensile force generated by the buoyancy is transmitted to the connected floating body parts, and the distance from the seabed ground surface to the floating body parts is kept substantially constant.

  The self-sediment prevention device for steel pipe piles according to a third invention is the first invention or the second invention, wherein the floating body portion has a highly airtight space, and an intake / exhaust portion for sucking and discharging fluid inside the space, The suction / exhaust part controls the buoyancy of the floating body part by sucking and discharging the fluid inside the space.

  The steel pipe pile self-sediment prevention device according to a fourth aspect of the present invention is the third aspect of the present invention, further comprising a sensor unit for measuring a position in the height direction of the floating body, and the intake / exhaust unit is based on the measurement result of the sensor unit. The fluid in the space is sucked and discharged to keep the distance from the seabed ground surface to the floating body portion substantially constant.

  According to a fifth aspect of the present invention, there is provided the steel pipe pile self-sediment prevention device according to the fourth aspect, wherein the sensor unit measures a water pressure acting on the floating body part and a water pressure on the seabed ground surface, and the floating body part. It has at least one of the positional information apparatus which measures an altitude.

  The self-sediment prevention device for steel pipe piles according to a sixth aspect of the present invention, in any one of the first to fifth aspects of the present invention, further comprises a cushioning material provided between the floating body part and the steel pipe pile, It is intended to prevent rolling of the steel pipe pile.

  The steel pipe pile self-sink prevention structure according to the seventh aspect of the present invention is a steel pipe pile self-sink prevention structure for preventing the steel pipe pile self-sink, and the steel pipe pile self-sediment prevention apparatus floats in seawater and has a floating body connected to the steel pipe pile. And a guide pile placed in the seabed ground, a steel pipe pile and a guide frame connected to the guide pile, and the floating body part transmits buoyancy to the steel pipe pile to be connected. The floating body part and the guide frame are in a state in which the lower end part of the steel pipe pile provided in the rooting part filled with a fluidized solidifying material in the seabed ground is separated from the bottom part of the rooting part. The position of the steel pipe pile is maintained.

  The steel pipe pile self-settlement prevention method according to the eighth invention is a steel pipe pile self-sink prevention method for preventing the steel pipe pile self-sink, and is a pile driving process in which a steel pipe pile self-sink prevention device is attached and the steel pipe pile is driven into the seabed ground. The steel pipe pile self-sink prevention device has a floating body part floating in seawater, and the pile driving step connects the steel pipe pile to the floating body part, and the seabed ground is filled with a fluidized solidified material. The lower end portion of the steel pipe pile provided in the solidified portion is separated from the bottom surface portion of the root solidified portion, the position of the steel pipe pile is maintained, and the fluidized solidified material is consolidated. And

  The self-sediment prevention method for steel pipe piles according to a ninth aspect of the present invention is the method according to the eighth aspect, wherein in the pile driving step, a constraining material is connected to the floating body part and an anchor placed in the seabed ground, and the floating body is separated from the seabed ground surface. The distance to the part is kept substantially constant.

  The self-sediment prevention method for steel pipe piles according to a tenth aspect of the invention is the eighth invention, wherein the floating body portion has a highly airtight space and an intake / exhaust portion for sucking and discharging fluid inside the space. The step is characterized in that the fluid inside the space is sucked and discharged by the suction and discharge part, and the distance from the seabed ground surface to the floating body part is kept substantially constant.

  The self-sediment prevention method for steel pipe piles according to an eleventh aspect of the invention is the eighth invention, wherein the pile driving step connects a guide frame to the lead pile placed in the seabed ground and the steel pipe pile, and the floating body portion and the The guide frame is characterized in that the position of the steel pipe pile is maintained in a state where the lower end portion of the steel pipe pile is separated from the bottom surface portion of the root-solidified portion.

  According to 1st invention-6th invention, a floating body part and a steel pipe pile are connected, and the position of a steel pipe pile is hold | maintained in the state which spaced apart the lower end part of the steel pipe pile from the bottom face part of the rooting part, Offshore including the construction of root-pipe-type steel pipe piles, because it can reduce the load on other structures such as guide frames and guide piles that support piles, and can reduce the number of other structures to be installed It is possible to shorten the construction period of the entire construction and reduce the material construction cost.

  In particular, according to the second aspect of the present invention, one or a plurality of restraining members connected to the floating body part and the anchor are provided, and the distance from the seabed ground surface to the floating body part is kept substantially constant, thereby supporting the steel pipe pile. Without using the configuration, the position of the steel pipe pile can be maintained in a state where the lower end of the steel pipe pile is separated from the bottom surface of the root consolidation part. It is possible to reduce the construction period and material costs.

  In particular, according to the third to fifth aspects of the present invention, the intake / exhaust part absorbs / extracts the fluid inside the space and keeps the distance from the seabed ground surface to the floating body part substantially constant, thereby supporting the steel pipe pile. Without using the configuration, the position of the steel pipe pile can be maintained in a state where the lower end of the steel pipe pile is separated from the bottom surface of the root consolidation part. It is possible to reduce the construction period and material costs.

  In particular, according to the sixth aspect of the present invention, by providing a cushioning material between the floating body part and the steel pipe pile, the rolling of the steel pipe pile accompanying the waves can be suppressed, so that it is hard to be affected by the marine environment. It is possible to implement steel pipe piles of the type.

  According to 7th invention, a floating body part and a steel pipe pile are connected, and the position of a steel pipe pile is hold | maintained in the state which left | separated the lower end part of the steel pipe pile from the bottom face part of the root hardening part. The number of steel pipe piles that can be connected to one lead frame is reduced, and the number of lead piles and guide frames can be reduced. It is possible to reduce the construction time and material cost.

  According to the eighth aspect of the invention, there is provided a pile driving step for attaching the floating body portion of the steel pipe pile self-sinking device and driving the steel pipe pile into the seabed ground. In the pile driving process, other configurations that support the steel pipe pile by holding the position of the steel pipe pile and consolidating the fluidized solidified material while keeping the lower end of the steel pipe pile away from the bottom part of the rooting part Can reduce the load on the road, and can reduce the number of other configurations, reducing the construction period of the entire offshore construction including the construction of the solidified steel pipe pile and reducing the material cost. It is possible to realize.

  In particular, according to the ninth invention, in the pile driving process, the anchoring material is connected to the anchor and the floating body part, and the distance from the seabed ground surface to the floating body part is kept substantially constant, so that another structure for supporting the steel pipe pile is provided. Without using the steel pipe pile, the bottom of the steel pipe pile is separated from the bottom surface of the root consolidation part, and the position of the steel pipe pile can be maintained and the fluidized solidified material can be consolidated. It is possible to shorten the construction period of the entire offshore construction including the construction of and reduce the material construction cost.

  In particular, according to the tenth invention, in the pile driving process, the fluid inside the space is sucked and discharged by the sucking and discharging part, and the distance from the seabed ground surface to the floating body part is kept substantially constant, thereby supporting the steel pipe pile. Without using the configuration, with the bottom end of the steel pipe pile spaced from the bottom part of the rooting part, the position of the steel pipe pile can be maintained and the fluidized solidification material can be consolidated. It is possible to shorten the construction period of the entire offshore construction including the construction of steel pipe piles and reduce the material construction cost.

  In particular, according to the eleventh invention, in the pile driving step, the guide frame is connected to the guide pile and the steel pipe pile placed in the seabed ground, and the lower end portion of the steel pipe pile is fixed by the floating body and the guide frame. Steel pipe pile that can be connected to a single lead frame by reducing the load on the lead pile and the lead frame by holding the position of the steel pipe pile in a state separated from the bottom surface of the steel and solidifying the fluidized solidification material. It is possible to reduce the construction time of the lead pile and the lead frame and the reduction of the material cost in the construction of the solidified steel pipe pile because the number of lead piles and lead frames can be reduced. .

It is a perspective view which shows 1st Embodiment of the self-sediment prevention apparatus of the steel pipe pile to which this invention is applied. (A) is a top view which shows the wire used as the connection jig | tool in 1st Embodiment of the self-sediment prevention apparatus of the steel pipe pile which applied this invention, (b) was used as the connection jig | tool. It is a partial expanded sectional view which expands and shows a wire. (A) is a top view which shows the volt | bolt and nut which were used as a connection jig in 1st Embodiment of the self-sediment prevention apparatus of the steel pipe pile to which this invention is applied, (b) is used as the connection jig. It is a partial expanded sectional view which expands and shows the used volt | bolt and nut. (A) is a top view which shows the damper used as a shock absorbing material in 1st Embodiment of the self-sediment prevention apparatus of the steel pipe pile to which this invention is applied, (b) is the damper used as the shock absorbing material. It is a partial expanded sectional view shown expanding. (A) is a top view which shows the vibration proof rubber used as a shock absorbing material in 1st Embodiment of the self-sediment prevention apparatus of the steel pipe pile to which this invention is applied, (b) was used as the shock absorbing material. It is a partial expanded sectional view which expands and shows vibration-proof rubber. (A) is a top view which shows the wire used as a restraint material in 1st Embodiment of the self-sediment prevention apparatus of the steel pipe pile to which this invention is applied, (b) is the wire used as the restraint material. It is a partial expanded sectional view shown expanding. It is a front view which shows the force which acts on each structure in 1st Embodiment of the self-sediment prevention apparatus of the steel pipe pile which applied this invention. It is a front view which shows the first half of the pile driving process which attaches the self-sediment prevention apparatus of the steel pipe pile in 1st Embodiment of the steel pipe pile self-sink prevention construction method to which this invention is applied, and drives a steel pipe pile into the seabed ground. (A) And (b) shows the latter half of the pile driving process which attaches the steel pipe pile self-sediment prevention apparatus in 1st Embodiment of the steel pipe pile self-sink prevention construction method to which this invention is applied, and drives a steel pipe pile into the seabed ground. It is a front view, (c) is a front view which shows the removal process which removes the self-sediment prevention apparatus of the steel pipe pile in 1st Embodiment of the self-sediment prevention method of the steel pipe pile to which this invention is applied. It is a front view which shows 2nd Embodiment of the self-sediment prevention apparatus of the steel pipe pile to which this invention is applied. It is a front view which shows 2nd Embodiment of the self-sediment prevention apparatus of a steel pipe pile provided with the sensor part to which this invention is applied. It is a front view which shows the first half of the pile driving process which attaches the self-sediment prevention apparatus of the steel pipe pile in 2nd Embodiment of the self-sediment prevention method of the steel pipe pile to which this invention is applied, and drives a steel pipe pile into the seabed ground. (A) is a front view showing the second half of a pile driving process in which a steel pipe pile self-sink prevention device in a second embodiment of the steel pipe pile self-sink prevention method to which the present invention is applied is attached and the steel pipe pile is driven into the seabed ground. (B) is a front view which shows the removal process which removes the self-sediment prevention apparatus of the steel pipe pile in 2nd Embodiment of the self-sediment prevention method of the steel pipe pile to which this invention is applied. It is a front view which shows the self-sediment prevention structure of the steel pipe pile to which this invention is applied. It is a front view which shows the first half of the pile driving process which attaches the self-sediment prevention structure of the steel pipe pile in the self-sediment prevention method of the steel pipe pile to which this invention is applied, and drives a steel pipe pile into the seabed ground. It is a front view which shows the latter half of the pile driving process which attaches the self-sediment prevention structure of the steel pipe pile in the self-sediment prevention method of the steel pipe pile to which this invention is applied, and drives a steel pipe pile into the seabed ground. It is a front view which shows the removal process which removes the self-sediment prevention structure of the steel pipe pile in the self-sediment prevention method of the steel pipe pile to which this invention is applied.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a first embodiment for carrying out a steel pipe pile self-sink prevention device 1 to which the present invention is applied will be described in detail with reference to the drawings.

  The steel pipe pile self-sink prevention device 1 to which the present invention is applied is used to prevent self-sedimentation of a solidified steel pipe pile 8 mainly constructed at sea as shown in FIG.

  As the steel pipe pile 8, a spiral steel pipe (for example, an outer diameter of 400 mm or more and 1600 mm or less) is mainly used. The steel pipe pile 8 has, for example, a connecting portion 8a such as a perforated steel plate, and is connected to the connecting jig 3 such as a wire using the connecting portion 8a. The connection part 8a is attached to the outer periphery of the steel pipe pile 8 by welding or the like. For example, a plurality of connection portions 8a are provided in a number of three or more. The plurality of connecting portions 8a are provided at equal intervals on the same circumference, for example, with the axial direction of the steel pipe pile 8 as the center. The plurality of connecting portions 8a are not limited to those provided at equal intervals on the same circumference.

  A plurality of steel pipe piles 8 are mainly applied to a pier foundation or the like in harbor construction. The steel pipe pile 8 extends in the height direction Z, and a lower end portion 8u is driven into the seabed ground 9. A lower end portion 8 u of the steel pipe pile 8 is provided in a root consolidation portion 81 in the seabed ground 9. The steel pipe pile 8 is provided with the lower end portion 8u in a state of being separated from the bottom surface portion 81u of the root hardening portion 81, so that the load of the steel pipe pile 8 is dispersed from the lower end portion 8u and a support force is obtained.

  In the construction of the steel pipe pile 8, the steel pipe pile 8 is provided with a root solidification by filling and solidifying the solidified portion 81 around the lower end portion 8u with a fluidized solidifying material (for example, cement milk). At this time, the steel pipe pile 8 may have the lower end portion 8u positioned on the seabed ground 9 in contact with the bottom surface portion 81u mainly due to self-sedimentation due to its own weight before the fluidized solidified material is consolidated. It is possible that a large force acts locally on the seabed ground 9 in contact with the lower end portion 8u, the seabed ground 9 is destroyed, and sufficient supporting force cannot be obtained. For this reason, the steel pipe pile 8 prevents self-sedimentation due to its own weight in a state where the fluidized solidified material is not consolidated, and maintains the position of the steel pipe pile 8 in a state where the lower end portion 8u is separated from the bottom surface portion 81u. It is necessary to distribute the load of the lower end portion 8u in the rooting portion 81.

  The steel pipe pile self-sink prevention device 1 to which the present invention is applied includes a floating body portion 2 that floats in seawater and is connected to the steel pipe pile 8.

  The floating body 2 is mainly made of a steel container, and has a highly airtight space 20 s that can hold a fluid such as air or seawater for a long time. The floating body 2 may be made of, for example, a resin material in addition to a steel material.

  For example, a cylindrical container surrounding the outer periphery of the steel pipe pile 8 is used as the floating body 2, and a hollow part 20 that is slightly larger than the outer diameter of the steel pipe pile 8 is formed. The floating body 2 is mainly in the form of a cylinder having an outer diameter of 2500 mm, a thickness of 150 mm, and a total length of about 15 m with respect to the steel pipe pile 8 having an outer diameter of 1600 mm, a plate thickness of 22 mm, and a total length of about 20 m. The shape of the floating body 2 may be, for example, a solid shape such as a spherical shape in addition to a cylindrical shape.

  The floating body 2 has, for example, a first connection portion 2a and a second connection portion 2b such as perforated steel plates, and a wire or the like is connected to at least one of the first connection portion 2a and the second connection portion 2b. Also good. As for the floating body part 2, the 1st connection part 2a is mainly attached to the inner surface of a container by welding etc., and the 2nd connection part 2b is attached to the outer surface of a container by welding etc. mainly. For example, a plurality of first connection portions 2a are provided in a number of three or more. The plurality of first connection portions 2a are provided at equal intervals on the same circumference, for example, with the axial direction of the steel pipe pile 8 as the center. The plurality of first connecting portions 2a are not limited to those provided at equal intervals on the same circumference. For example, one or a plurality of second connection portions 2b are provided, and more preferably a plurality of two or more second connection portions 2b are provided. For example, the plurality of second connection portions 2b are provided at equal intervals on the same circumference with the axial direction of the steel pipe pile 8 as the center. The plurality of second connection portions 2b are not limited to those provided at equal intervals on the same circumference.

  The floating body 2 has, for example, an intake / exhaust portion 21 that sucks and discharges fluid inside the space 20s. The intake / exhaust part 21 is provided on the surface of the container of the floating body part 2. The intake / exhaust part 21 controls the buoyancy of the floating body part 2 by sucking and discharging fluid inside the space 20s, for example, seawater. The intake / exhaust part 21 has an intake / exhaust port that connects the inside and the outside of the space 20s, and may have a pump that sucks and discharges the fluid inside the space 20s, for example, and automatically sucks and discharges the fluid inside the space 20s. It may have a control circuit or the like.

  In the steel pipe pile self-sink prevention device 1 to which the present invention is applied, one floating body portion 2 is connected to one steel pipe pile 8, for example, a plurality of floating body portions 2 with respect to one steel pipe pile 8. May be linked. In the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, when a plurality of floating body portions 2 are used for one steel pipe pile 8, for example, each floating body portion 2 may have the same shape or a different shape. Good.

  In the steel pipe pile self-sink prevention device 1 to which the present invention is applied, as shown in FIG. 2, the floating body 2 is connected to the steel pipe pile 8 by a connecting jig 3 such as a wire. In the steel pipe pile self-sink prevention device 1 to which the present invention is applied, the first connection portion 2 a of the floating body portion 2 is provided above the connection portion 8 a of the steel pipe pile 8 in the height direction Z. In the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, the first connecting portion 2 a and the connecting portion 8 a are connected by the connecting jig 3 so that a tensile force acts on the connecting jig 3. At this time, the buoyancy of the floating body 2 is transmitted to the steel pipe pile 8.

  In FIG. 2A, four connecting jigs 3 are provided, but a plurality of connecting jigs 3 may be provided. The plurality of connecting jigs 3 are provided, for example, at equal intervals on the same circumference with the axial direction of the steel pipe pile 8 as the center. The plurality of connecting jigs 3 are not limited to those provided at equal intervals on the same circumference.

  In the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, a wire and a nut may be used as the connecting jig 3 as shown in FIG. In this case, the self-sediment prevention device 1 for a steel pipe pile to which the present invention is applied has an upper end at which the first connecting portion 2a and the connecting portion 8a are located at substantially the same position along the height direction Z and can be bolted. Or provided at the lower end and adjacent to each other along the first direction X or the second direction Y. In the steel pipe pile self-sink prevention device 1 to which the present invention is applied, the first connecting portion 2a is coupled to the connecting portion 8a by a bolt screwed to a nut, and the buoyancy of the floating body portion 2 is transmitted to the steel pipe pile 8. It becomes.

  The steel pipe pile self-sink prevention device 1 to which the present invention is applied includes a buffer material 5 such as a damper, as shown in FIG. 4, for example. In the steel pipe pile self-sink prevention device 1 to which the present invention is applied, the first connection portion 2a and the connection portion 8a are provided at substantially the same position along the height direction Z, and the first direction X or the second direction Y Along each other. In the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied, the buffer material 5 is coupled to the first connection portion 2a and the connection portion 8a facing each other using bolts or the like. At this time, the buoyancy of the floating body 2 is transmitted to the steel pipe pile 8. In the steel pipe pile self-sink prevention device 1 to which the present invention is applied, the length of the buffer material 5 varies according to the force applied from the floating body 2 (in the direction of the arrow in FIG. 4B). Prevent rolling.

  Although four buffer materials 5 are provided in FIG. 4A, a plurality of buffer materials 5 may be provided. The plurality of buffer materials 5 are provided, for example, at equal intervals on the same circumference with the axial direction of the steel pipe pile 8 as the center. In addition, the some buffer material 5 is not limited to what is provided at equal intervals on the same periphery.

  The steel pipe pile self-sediment prevention device 1 to which the present invention is applied uses a damper as the buffer material 5, and for example, as shown in FIG. 5, an anti-vibration rubber or the like may be used as the buffer material 5. In this case, in the steel pipe pile self-sink prevention device 1 to which the present invention is applied, the cushioning material 5 is connected to the inner surface of the floating body 2 and the outer periphery of the steel pipe pile 8 using bolts or the like (not shown). At this time, the buoyancy of the floating body 2 is transmitted to the steel pipe pile 8. In the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, the buffer material 5 undergoes shear deformation (in the direction of the arrow in FIG. 5A) according to the force applied from the floating body 2, and the steel pipe pile 8 rolls. prevent.

  The steel pipe pile self-sediment prevention device 1 to which the present invention is applied is provided with at least one of the connecting jig 3 and the buffer material 5, for example, without providing the connecting jig 3 and the buffer material 5, It may be connected. In this case, in the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, for example, the floating body 2 whose volume is expanded may be in close contact with and connected to the steel pipe pile 8. At this time, the buoyancy of the floating body portion 2 is transmitted to the steel pipe pile 8 by a frictional force or the like.

  The steel pipe pile self-sediment prevention device 1 to which the present invention is applied includes a restraint 4 such as a wire as shown in FIG. 6, for example. In the steel pipe pile self-sink prevention device 1 to which the present invention is applied, the restraint member 4 is connected to the second connecting portion 2 b of the floating body portion 2 and the anchor 41 placed in the seabed ground 9. In the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, the second connecting portion 2 b and the anchor 41 are connected by the restraint material 4 so that a tensile force acts on the restraint material 4. At this time, the tensile force of the restraint member 4 is transmitted to the floating body portion 2, and the distance from the seabed ground 9 surface to the floating body portion 2 is kept substantially constant.

  One or a plurality of restraining materials 4 are provided, more preferably a plurality of three or more. For example, the plurality of restraining members 4 are provided at equal intervals on the same circumference around the axial direction of the steel pipe pile 8. The plurality of restraining materials 4 are not limited to those provided at equal intervals on the same circumference.

  In the steel pipe pile self-sink prevention apparatus 1 to which the present invention is applied, as shown in FIG. 7, a self-weight G acts on the steel pipe pile 8 in the sinking direction and is transmitted from the connected floating body 2 in the floating direction. Buoyancy F acts. At this time, since the buoyancy F is equal to or greater than the own weight G, the self-sinking of the steel pipe pile 8 can be prevented by connecting the floating body portion 2 to the steel pipe pile 8.

  Further, buoyancy F acts on the floating body 2 in the floating direction, and the tensile force generated by the buoyancy F from the weight G transmitted from the connected steel pipe pile 8 and the constraining material 4 connected in the sinking direction. T acts. At this time, since the resultant force of the dead weight G and the tensile force T is substantially equal to the buoyancy F, the distance from the surface of the seabed 9 to the floating body portion 2 is kept substantially constant, and the lower end portion 8u of the steel pipe pile 8 is fixed to the root portion 81. The position of the steel pipe pile 8 can be held in a state of being separated from the bottom surface portion 81u.

  Here, the self-sediment prevention method for steel pipe piles to which the present invention is applied is as shown in FIGS. 8 (a) to 9 (b). A pile driving process is provided. As shown in FIG. 9C, the steel pipe pile self-settlement prevention method to which the present invention is applied is provided with the steel pipe pile self-sediment prevention device 1 as necessary after the fluidized solidification material of the root-solidifying portion 81 is consolidated. You may provide the removal process to remove.

  In the pile driving process, as shown in FIG. 8A, the floating body 2 is floated above the planned placement position of the steel pipe pile 8, and the anchor 41 is driven around the planned placement position of the steel pipe pile 8. The In the pile driving step, when a plurality of anchors 41 are to be driven, for example, the plurality of anchors 41 are driven at equal intervals on the same circumference around the height direction Z of the planned placement position of the steel pipe pile 8. . In the pile driving process, the anchors 41 are not limited to those that are driven at equal intervals on the same circumference. First, the anchor 41 may be driven around the planned placement position of the steel pipe pile 8, and the floating body 2 may be floated on the sea.

  Next, in the pile driving process, as shown in FIG. 8 (b), the steel pipe pile 8 is inserted into the hollow portion 20 by using a vibro hammer (not shown) or the like and placed in the seabed ground 9. In the pile driving step, a plurality of nozzles for injecting water or a fluidized solidifying material are attached in advance in the circumferential direction on the lower end portion 8u side of the steel pipe pile 8 at a predetermined interval. Water is ejected from this nozzle to drive the steel pipe pile 8, and then a rooting portion 81 filled with a fluidized solidifying material is provided around the lower end portion 8 u of the steel pipe pile 8 driven into the seabed ground 9. It is done. In the pile driving process, the steel pipe pile 8 is supported by a marine crane or the like that suspends a vibratory hammer, and the position of the steel pipe pile 8 is determined while the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the rooting portion 81. Hold. It should be noted that in placing the steel pipe pile 8, not the water but the fluidized solidifying material may be injected, or the water or the fluidized solidifying material may not be injected and only the vibro hammer may be used.

  In the pile driving process, for example, in addition to using a vibro hammer or the like, for example, using a drill rod (not shown) inserted into the steel pipe pile 8, the steel pipe pile 8 is driven into the seabed ground 9, and then the lower end of the steel pipe pile 8. A root hardening portion 81 filled with a fluidized solidifying material may be provided around 8u.

  Next, in the pile driving process, as shown in FIG. 9A, the floating body 2 and the steel pipe pile 8 are connected using a connecting jig 3 such as a wire. In the pile driving process, a diver or the like attaches the connecting jig 3 to the first connection portion 2a of the floating body portion 2 and the connection portion 8a of the steel pipe pile 8 in the sea.

  In the pile driving process, before attaching the connecting jig 3 to the first connecting portion 2a and the connecting portion 8a, for example, the intake / exhaust portion 21 supplies seawater into the space 20s of the floating portion 2 and the floating portion 2 Sink. In the pile driving process, after attaching the connecting jig 3 to the first connection portion 2a and the connection portion 8a, for example, the seawater in the space 20s is drained by the intake / exhaust portion 21 to float the floating body portion 2 (In the direction of the arrow in FIG. 9A). In the pile driving process, when the floating body portion 2 is lifted, the first connecting portion 2a and the connecting portion 8a are connected by the connecting jig 3 so that a tensile force acts on the connecting jig 3. At this time, the buoyancy of the floating body 2 is transmitted to the steel pipe pile 8.

  In the pile driving process, when a tensile force is applied to the connecting jig 3, the intake / exhaust portion 21 absorbs / extracts seawater into the space 20 s and controls the buoyancy of the floating body portion 2. Air may be sucked into and discharged from the inside, and the buoyancy of the floating body 2 may be controlled. For example, after the floating body 2 is intentionally pushed into the sea, the connecting jig 3 is attached and the pushing of the floating body 2 is finished. A tensile force may act on the connecting jig 3.

  In the pile driving process, the floating body 2 and the steel pipe pile 8 are connected using the connecting jig 3, and the floating body 2 and the steel pipe pile 8 are connected using, for example, the cushioning material 5 shown in FIGS. 4 and 5. May be.

  Next, in the pile driving process, as shown in FIG. 9B, the restraint material 4 such as a wire is connected to the floating body 2 and the anchor 41. In the pile driving process, a diver or the like attaches the restraint material 4 to the second connection portion 2b and the anchor 41 of the floating body portion 2 in the sea.

  In the pile driving process, after attaching the restraint 4 to the second connecting portion 2b and the anchor 41, for example, the seawater inside the space 20s is drained by the intake / exhaust portion 21 to float the floating body portion 2 (FIG. 9). (B) arrow direction). In the pile driving process, when the floating body 2 is lifted, the floating body 2 and the anchor 41 are connected by the restraining material 4 so that a tensile force acts on the restraining material 4. At this time, the tensile force of the restraining material 4 is transmitted to the floating body 2.

  In the pile driving process, after connecting the restraint 4 to the floating body 2 and the anchor 41, the steel pipe pile 8 is removed from a vibratory hammer or the like suspended by a marine crane or the like. At this time, in the pile driving process, the tensile force of the restraining material 4 is transmitted to the floating body 2, so that the distance from the surface of the seabed 9 to the floating body 2 is kept substantially constant, and the floating body 2 is more than necessary. The position of the steel pipe pile 8 is maintained in a state in which the lifting is prevented and the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the rooting portion 81. In this state, the fluidized solidified material filled in the root hardening part 81 is consolidated (for example, about 1 to 2 days).

  In the pile driving process, after placing the anchor 41 and floating the floating body portion 2 on the sea, in addition to the order of placing the steel pipe pile 8, for example, after placing the steel pipe pile 8, the anchor 41 is driven. You may carry out in order in which the installation and the floating-body part 2 are floated on the sea.

  The removal process is performed as necessary after the pile driving process. In the removal process, as shown in FIG. 9C, the self-sediment prevention device 1 for the steel pipe pile is removed after the fluidized solidified material of the root hardening portion 81 is consolidated. In the removal process, seawater inside the space 20s of the floating body 2 is adjusted so that no tensile force acts on the restraint 4 and the connecting jig 3, and a diver or the like is connected to the second connecting portion 2b and the anchor 41. The restraint material 4 is removed and collected, and the anchor 41 placed in the seabed ground 9 is pulled out and collected. In the removal process, a diver or the like removes and collects the connecting jig 3 connected to the first connecting portion 2a and the connecting portion 8a.

  In the removal step, after collecting the restraining material 4 and the anchor 41, in addition to the order of collecting the connecting jig 3, for example, after collecting the connecting jig 3, it is performed in the order of collecting the restraining material 4 and the anchor 41. Also good.

  In the removal step, the construction of the steel pipe pile 8 is completed by removing the restraint 4 and the connecting jig 3 and then collecting the floating body 2. At this time, the bottom end portion 8 u of the steel pipe pile 8 is provided in the root consolidation portion 81 in a state of being separated from the bottom surface portion 81 u of the root consolidation portion 81. The floating body part 2, the connecting jig 3, and the restraining material 4 collected in the removal process may be reused in another pile driving process, for example.

  The steel pipe pile self-sediment prevention device 1 to which the present invention is applied includes one or a plurality of restraining members 4 connected to the floating body 2 and the anchor 41, and the distance from the surface of the seabed 9 to the floating body 2 is substantially constant. By maintaining, the position of the steel pipe pile 8 can be maintained in a state in which the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the rooting portion 81 without using another configuration that supports the steel pipe pile 8. Therefore, it is possible to realize shortening of the construction period of the entire marine construction including construction of the solidified steel pipe pile 8 and reduction of material construction costs.

  The steel pipe pile self-sediment prevention device 1 to which the present invention is applied is particularly provided with three or more plural restraining materials 4 and is provided at equal intervals on the same circumference around the axial direction of the steel pipe pile 8. Since the rolling force of the steel pipe pile 8 caused by waves and the like is evenly transmitted to each restraint 4, it is possible to carry out the construction of the solidified steel pipe pile 8 that is hardly affected by the marine environment. Is possible.

  Since the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied includes the buffer material 5 between the floating body portion 2 and the steel pipe pile 8, the rolling of the steel pipe pile 8 due to waves can be suppressed, so It is possible to carry out the construction of the solidified steel pipe pile 8 that is not easily affected by this.

  The steel pipe pile self-settlement prevention method to which the present invention is applied includes a pile driving process in which the floating body portion 2 of the steel pipe pile self-sink prevention device 1 is attached and the steel pipe pile 8 is driven into the seabed ground 9. In the pile driving process, the restraint material 4 is connected to the anchor 41 and the floating body portion 2 and the distance from the surface of the seabed ground 9 to the floating body portion 2 is kept substantially constant, without using another configuration that supports the steel pipe pile 8. In the state where the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the root consolidation portion 81, the position of the steel pipe pile 8 can be maintained and the fluidized solidified material can be consolidated. It is possible to shorten the construction period of the entire offshore construction including construction of the steel pipe pile 8 and reduce the material construction cost.

  The self-settlement prevention method for steel pipe piles to which the present invention is applied is, in particular, by carrying out a removal step of removing the self-sediment prevention device 1 for steel pipe piles after consolidating the fluidized solidified material filled in the root consolidation part 81. Since the steel pipe pile self-sink prevention device 1 can be recovered and reused, it is possible to reduce material costs.

  Next, 2nd Embodiment for implementing the self-sediment prevention apparatus 1 of the steel pipe pile to which this invention is applied is described in detail, referring drawings. In addition, about the component same as the component mentioned above, the description below is abbreviate | omitted by attaching | subjecting the same code | symbol.

  As shown in FIG. 10, the steel pipe pile self-sediment prevention device 1 to which the present invention is applied has an intake / exhaust portion 21 having a gas intake / exhaust port 21a and a liquid discharge port 21b above the sea surface, and from the sea surface. Also has a liquid inlet 21c below. In the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, the intake / exhaust portion 21 has a gas intake / exhaust port 21a, a liquid discharge port 21b, and a liquid intake port 21c, for example, for gas above the sea surface. One intake / exhaust port sharing the intake / exhaust flow and the liquid discharge port, and a liquid intake port 21c below the sea surface may be provided.

  The steel pipe pile self-sediment prevention device 1 to which the present invention is applied absorbs and discharges fluid from the inside of the space 20s of the floating body portion 2 according to the tide level by the intake and exhaust portion 21, and increases the distance from the surface of the seabed ground 9 to the floating body portion 2. Keep almost constant. The steel pipe pile self-sink prevention device 1 to which the present invention is applied is, for example, for liquids when the distance between the surface of the seabed 9 and the sea surface increases from low tide (FIG. 10 (a)) to high tide (FIG. 10 (b)). Seawater 91 is sucked into the space 20s from the suction port 21c and the floating body 2 is sunk, so that the distance between the surface of the seabed ground 9 and the floating body 2 is kept substantially constant. The steel pipe pile self-sediment prevention device 1 to which the present invention is applied, for example, discharges seawater 91 in the space 20s from the liquid discharge port 21b when the distance between the seabed 9 and the sea surface decreases from high tide to low tide. Thus, the distance between the surface 9 of the seabed and the floating body 2 is kept substantially constant by floating the floating body 2. For this reason, in the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied, the seawater 91 in the space 20s is the smallest at the low tide shown in FIG. 10 (a) and the most at the high tide shown in FIG. 10 (b).

  The steel pipe pile self-sediment prevention device 1 to which the present invention is applied includes, for example, a sensor unit 60 that measures the position in the height direction Z of the floating body 2. In the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, the suction / exhaust part 21 absorbs / discharges the fluid inside the space 20 s based on the measurement result of the sensor part 60, and the surface from the seabed ground 9 to the floating part 2. Keep the distance approximately constant.

  In the steel pipe pile self-sink prevention device 1 to which the present invention is applied, for example, as shown in FIG. 11 (a), the sensor unit 60 has a water pressure gauge. In the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied, the hydraulic pressure gauge includes a first hydraulic pressure gauge 61a provided on the floating body 2 below the sea level and a second hydraulic pressure gauge 61b provided on the surface of the seabed ground 9. And have. In the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied, the first water pressure gauge 61a measures the water pressure acting on the floating body part 2, and the second water pressure gauge 61b measures the water pressure on the surface of the seabed ground 9.

  In the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied, the suction / exhaust part 21 sucks and discharges the fluid inside the space 20s based on the difference between the results measured by the water pressure gauges 61a and 61b, and the surface of the seabed 9 The distance from the floating body 2 to the floating body 2 is kept substantially constant.

  In the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied, for example, when the difference between the results measured by the water pressure gauges 61a and 61b is within a certain range, the intake / exhaust part 21 extends from the surface of the seabed ground 9 to the floating part 2. Is determined to be constant, and the seawater 91 is not sucked or discharged into the space 20s. In the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, for example, when the difference between the results measured by the water pressure gauges 61a and 61b is out of a certain range, the intake / exhaust portion 21 is placed in the seawater 91 in the space 20s. The distance from the bottom 9 of the seabed to the floating body 2 is kept substantially constant.

  The steel pipe pile self-sink prevention device 1 to which the present invention is applied has a position information device 62 such as GPS (Global Positioning System) in which the sensor unit 60 mainly measures altitude, as shown in FIG. 11B, for example. In the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied, the position information device 62 is provided in the floating body 2 above the sea surface.

  In the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied, the intake / exhaust part 21 absorbs / extracts the fluid inside the space 20s based on the observation result of the position information device 62, and the floating part 2 from the surface of the seabed ground 9 Keep the distance to approximately constant.

  In the steel pipe pile self-sink prevention device 1 to which the present invention is applied, for example, when the measurement result of the position information device 62 is within a certain range, the intake / exhaust portion 21 has a constant distance from the surface of the seabed ground 9 to the floating body portion 2. Therefore, the seawater 91 is not sucked into or discharged from the space 20s. In the self-sediment prevention device 1 for steel pipe piles to which the present invention is applied, for example, when the measurement result of the position information device 62 deviates from a certain range, the intake / exhaust portion 21 absorbs and discharges seawater 91 into the space 20s. The distance from the bottom 9 to the floating body 2 is kept constant.

  Here, the self-sediment prevention method for steel pipe piles to which the present invention is applied is as shown in FIGS. 12 (a) to 13 (a). A pile driving process is provided. As shown in FIG. 13 (b), the steel pipe pile self-settlement prevention method to which the present invention is applied is provided with the steel pipe pile self-sink prevention device 1 as necessary after the fluidized solidification material of the root hardening portion 81 is consolidated. You may provide the removal process to remove.

  In the pile driving process, first, the floating body 2 is floated on the sea as shown in FIG. In the pile driving process, the floating body 2 is floated above the planned placement position of the steel pipe pile 8.

  Next, in the pile driving process, as shown in FIG. 12 (b), the steel pipe pile 8 is inserted into the hollow portion 20 using a vibro hammer (not shown) or the like and is placed in the seabed ground 9. In the pile driving step, a plurality of nozzles for injecting water or a fluidized solidifying material are attached in advance in the circumferential direction on the lower end portion 8u side of the steel pipe pile 8 at a predetermined interval. Water is ejected from this nozzle to drive the steel pipe pile 8, and then a rooting portion 81 filled with a fluidized solidifying material is provided around the lower end portion 8 u of the steel pipe pile 8 driven into the seabed ground 9. It is done. In the pile driving process, the steel pipe pile 8 is supported by a marine crane or the like that suspends a vibratory hammer, and the position of the steel pipe pile 8 is determined while the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the rooting portion 81. Hold.

  Next, in the pile driving process, as shown in FIG. 13A, the floating body portion 2 and the steel pipe pile 8 are connected using a connecting jig 3 such as a wire. In the pile driving process, a diver or the like attaches the connecting jig 3 to the first connection portion 2a of the floating body portion 2 and the connection portion 8a of the steel pipe pile 8 in the sea.

  In the pile driving process, before attaching the connecting jig 3 to the first connection portion 2a and the connection portion 8a, for example, seawater is supplied into the space 20s of the floating portion 2 by the liquid suction port 21c, and the floating portion Sink 2 In the pile driving process, after attaching the connecting jig 3 to the first connection portion 2a and the connection portion 8a, for example, the seawater inside the space 20s is drained by the liquid discharge port 21b, and the floating body portion 2 To surface. In the pile driving process, when the floating body portion 2 is lifted, the first connecting portion 2a and the connecting portion 8a are connected by the connecting jig 3 so that a tensile force acts on the connecting jig 3. At this time, the buoyancy of the floating body 2 is transmitted to the steel pipe pile 8.

  In the pile driving process, after connecting the floating body 2 and the steel pipe pile 8, the steel pipe pile 8 is removed from a vibratory hammer or the like suspended by a marine crane or the like. At this time, in the pile driving process, the distance from the surface 9 of the seabed to the floating body 2 is kept substantially constant by sucking and discharging the fluid inside the space 20s by the suction and discharge part 21 according to the tide level. In a state where the lower end portion 8u is separated from the bottom surface portion 81u of the root hardening portion 81, the position of the steel pipe pile 8 is maintained. In this state, the fluidized solidified material filled in the root hardening portion 81 is consolidated.

  In the pile driving process, after the floating body portion 2 is floated on the sea, in addition to the order of placing the steel pipe pile 8, for example, after placing the steel pipe pile 8, the floating body portion 2 is floated on the sea. You may go.

  The removal process is performed as necessary after the pile driving process. In the removal step, as shown in FIG. 13 (b), the self-sediment prevention device 1 for the steel pipe pile is removed after the fluidized solidified material of the root hardening portion 81 is consolidated. In the removal step, seawater inside the space 20s of the floating body 2 is adjusted so that no tensile force acts on the connecting jig 3, and a diver or the like is connected to the first connecting part 2a and the connecting part 8a. The jig 3 is removed and collected.

  In the removal step, the construction of the steel pipe pile 8 is completed by collecting the floating body 2 after removing the connecting jig 3. At this time, the bottom end portion 8 u of the steel pipe pile 8 is provided in the root consolidation portion 81 in a state of being separated from the bottom surface portion 81 u of the root consolidation portion 81. The floating body part 2 and the connecting jig 3 collected in the removal process may be reused in another pile driving process, for example.

  In the steel pipe pile self-sediment prevention device 1 to which the present invention is applied, the suction and discharge part 21 sucks and discharges the fluid inside the space 20 s and keeps the distance from the surface 9 of the seabed ground to the floating body part 2 substantially constant. Since the position of the steel pipe pile 8 can be maintained in a state in which the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the root hardening portion 81 without using another configuration that supports the steel pile pile 8, It is possible to shorten the construction period of the entire offshore construction including construction of the steel pipe pile 8 and reduce the material construction cost.

  The steel pipe pile self-settlement prevention method to which the present invention is applied includes a pile driving process in which the floating body portion 2 of the steel pipe pile self-sink prevention device 1 is attached and the steel pipe pile 8 is driven into the seabed ground 9. In the pile driving process, the fluid inside the space 20s is sucked and discharged by the sucking and discharging part 21, and the distance from the surface of the seabed 9 to the floating body 2 is kept substantially constant, so that no other structure for supporting the steel pipe pile 8 is used. In addition, in the state where the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the root consolidation portion 81, the position of the steel pipe pile 8 can be held and the fluidized solidified material can be consolidated. It is possible to reduce the construction period of the entire offshore construction including construction of the steel pipe pile 8 and reduce the material construction cost.

  The self-settlement prevention method for steel pipe piles to which the present invention is applied is, in particular, by carrying out a removal step of removing the self-sediment prevention device 1 for steel pipe piles after consolidating the fluidized solidified material filled in the root consolidation part 81. Since the steel pipe pile self-sink prevention device 1 can be recovered and reused, it is possible to reduce material costs.

  Next, the steel pipe pile self-sink prevention structure 7 to which the present invention is applied will be described in detail with reference to the drawings. In addition, about the component same as the component mentioned above, the description below is abbreviate | omitted by attaching | subjecting the same code | symbol.

  As shown in FIG. 14, the steel pipe pile self-sink prevention structure 7 to which the present invention is applied includes a steel pipe pile self-sink prevention device 1 having a floating body portion 2, a lead pile 71 placed in the seabed ground 9, and a steel pipe. The pile 8 and the guide frame 72 connected with the guide pile 71 are provided.

  In the steel pipe pile self-sink prevention structure 7 to which the present invention is applied, a steel pipe is mainly used as the guide pile 71. In the self-sediment prevention structure 7 for steel pipe piles to which the present invention is applied, the guide pile 71 extends in the height direction Z from the sea and is placed in the seabed ground 9. In the steel pipe pile self-sink prevention structure 7 to which the present invention is applied, the root pile around which the fluidized solidifying material is consolidated is not provided around the lower end portion of the lead pile 71. It will be removed. In the steel pipe pile self-sink prevention structure 7 to which the present invention is applied, the guide pile 71 is aligned with, for example, a plurality of steel pipe piles 8 to be connected.

  The steel pipe pile self-sink prevention structure 7 to which the present invention is applied mainly uses H-shaped steel as the guide frame 72. In the self-sediment prevention structure 7 for a steel pipe pile to which the present invention is applied, the guide frame 72 extends substantially perpendicular to the guide pile 71 (substantially parallel to the sea surface) and is connected to the guide pile 71. In the steel pipe pile self-sink prevention structure 7 to which the present invention is applied, for example, the guide frame 72 supports three or more steel pipe piles 8.

  In the steel pipe pile self-sink prevention structure 7 to which the present invention is applied, the floating body portion 2 and the guide frame 72 are connected to the steel pipe pile 8, and the lower end portion 8 u of the steel pipe pile 8 is separated from the bottom surface portion 81 u of the root hardening portion 81. The position of the steel pipe pile 8 is maintained. The steel pipe pile self-sink prevention structure 7 to which the present invention is applied reduces the load on the guide frame 72 in which the floating body portion 2 supports the steel pipe pile 8. At this time, the floating body 2 can maintain the distance between the surface of the seabed ground 9 and the floating body 2 substantially constant, for example, even when the distance between the surface of the seabed ground 9 and the floating body 2 varies due to the tide level or the like. The load on the guide frame 72 can be reduced.

  Here, the self-settlement prevention method for steel pipe piles to which the present invention is applied includes a pile driving process in which a self-sink prevention structure 7 for steel pipe piles is attached and the steel pipe piles 8 are driven into the seabed ground 9 as shown in FIGS. Prepare. As shown in FIG. 17, the steel pipe pile self-settlement prevention method to which the present invention is applied is a removal in which the steel pipe pile self-sink prevention structure 7 is removed as necessary after the fluidized solidification material of the root consolidation part 81 is consolidated. A process may be provided.

  In the pile driving process, first, as shown in FIG. 15A, the guide pile 71 is placed in the seabed ground 9, and the guide frame 72 is connected to the guide pile 71. In the pile driving process, the guide frame 72 is disposed above the planned placement position of the steel pipe pile 8.

  Next, in the pile driving process, as shown in FIG. 15B, the floating body 2 is floated on the sea. At this time, in the pile driving step, the floating body 2 is floated above the planned placement position of the steel pipe pile 8. In the placing process, after placing the guiding pile 71 and arranging the guiding frame 72, in addition to the order of floating the floating body portion 2, for example, after floating the floating body portion 2, the guiding pile 71 is driven, You may carry out in the order which arrange | positions the guide frame 72. FIG.

  In the pile driving step, next, as shown in FIG. 16A, the steel pipe pile 8 is inserted into the hollow portion 20 using a vibro hammer or the like (not shown) and is placed in the seabed ground 9. In the pile driving step, a plurality of nozzles for injecting water or a fluidized solidifying material are attached in advance in the circumferential direction on the lower end portion 8u side of the steel pipe pile 8 at a predetermined interval. Water is ejected from this nozzle to drive the steel pipe pile 8, and then a rooting portion 81 filled with a fluidized solidifying material is provided around the lower end portion 8 u of the steel pipe pile 8 driven into the seabed ground 9. It is done. In the pile driving process, the steel pipe pile 8 is supported by a marine crane or the like that suspends a vibratory hammer, and the position of the steel pipe pile 8 is determined while the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the rooting portion 81. Hold.

  In the pile driving process, next, as shown in FIG. 16 (b), the guide frame 72 and the steel pipe pile 8 are connected, and the floating body 2 and the steel pipe pile 8 are connected using the connecting jig 3 such as a wire. Link. In the pile driving process, a diver or the like attaches the connecting jig 3 to the first connection portion 2a of the floating body portion 2 and the connection portion 8a of the steel pipe pile 8 in the sea.

  In the pile driving process, before attaching the connecting jig 3 to the first connecting portion 2a and the connecting portion 8a, for example, the intake / exhaust portion 21 supplies seawater into the space 20s of the floating portion 2 and the floating portion 2 Sink. In the pile driving process, after attaching the connecting jig 3 to the first connection portion 2a and the connection portion 8a, for example, the seawater in the space 20s is drained by the intake / exhaust portion 21 to float the floating body portion 2 (Arrow direction in FIG. 16B). In the pile driving process, when the floating body portion 2 is lifted, the first connecting portion 2a and the connecting portion 8a are connected by the connecting jig 3 so that a tensile force acts on the connecting jig 3. At this time, the buoyancy of the floating body 2 is transmitted to the steel pipe pile 8.

  In the pile driving process, after connecting the connecting jig 3 to the floating body 2 and the steel pipe pile 8, the steel pipe pile 8 is removed from a vibratory hammer or the like suspended by a marine crane or the like. At this time, in the pile driving process, the floating body portion 2 and the guide frame 72 support the steel pipe pile 8 instead of the vibro hammer, and the steel pipe pile 8 is in a state where the lower end portion 8u is separated from the bottom surface portion 81u of the rooting portion 81. The position of the pile 8 is maintained. In this state, the fluidized solidified material filled in the root hardening portion 81 is consolidated.

  In addition, in the pile driving process, for example, the steel pipe pile 8 is driven in addition to the order in which the steel pipe pile 8 is driven after the lead pile 71 is placed, the guide frame 72 is arranged, and the floating body 2 is floated. After that, the guide pile 71 may be placed, the guide frame 72 may be disposed, and the floating body portion 2 may be floated.

  The removal process is performed as necessary after the pile driving process. In the removal step, as shown in FIG. 17A, after the fluidized solidified material of the root hardening portion 81 is consolidated, the guide frame 72 is removed from the guide pile 71 and the steel pipe pile 8 and collected. In the removal process, after the guide frame 72 is removed and collected, the guide pile 71 placed in the seabed ground 9 is pulled out and collected.

  In the removal step, as shown in FIG. 17 (b), seawater inside the space 20s of the floating body 2 is adjusted so that no tensile force acts on the connecting jig 3, and a diver or the like is connected to the first connecting portion. The connecting jig 3 connected to 2a and the connecting portion 8a is removed and recovered. In the removal step, the construction of the steel pipe pile 8 is completed by collecting the floating body 2 after removing the connecting jig 3. At this time, the bottom end portion 8 u of the steel pipe pile 8 is provided in the root consolidation portion 81 in a state of being separated from the bottom surface portion 81 u of the root consolidation portion 81. The floating body part 2, the connecting jig 3, the guide pile 71, and the guide frame 72 collected in the removal process may be reused in another pile driving process, for example.

  The steel pipe pile self-sediment prevention device 1 to which the present invention is applied connects the floating body portion 2 and the steel pipe pile 8, and the steel pipe pile 8 is in a state where the lower end portion 8 u of the steel pipe pile 8 is separated from the bottom surface portion 81 u of the rooting portion 81. By maintaining the position of 8, it is possible to reduce the load on other components that support the steel pipe pile 8 and to provide root consolidation, and to reduce the number of other configurations to be provided. It is possible to shorten the construction period of the entire offshore construction including the construction of and reduce the material construction cost.

  The steel pipe pile self-sink prevention structure 7 to which the present invention is applied connects the floating body portion 2 and the steel pipe pile 8, and the steel pipe pile 8 is in a state where the lower end portion 8 u of the steel pipe pile 8 is separated from the bottom surface portion 81 u of the rooting portion 81. By holding the position of 8, the load on the guide pile 71 and the guide frame 72 is reduced, the number of steel pipe piles 8 that can be connected to one guide frame 72 is increased, and the guide pile 71 and the guide frame 72 are provided. Therefore, it is possible to reduce the construction time of the lead pile 71 and the lead frame 72 in the construction of the solidified steel pipe pile 8 and the material cost.

  The steel pipe pile self-settlement prevention method to which the present invention is applied includes a pile driving process in which the floating body portion 2 of the steel pipe pile self-sink prevention device 1 is attached and the steel pipe pile 8 is driven into the seabed ground 9. In the pile driving step, the steel pipe pile 8 is held in the state where the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the root hardening portion 81, and the position of the steel pipe pile 8 is held and the fluidized solidified material is consolidated. 8 can reduce the load on other components that support 8 and can reduce the number of other configurations, so that the construction period of the entire offshore construction including the construction of the solidified steel pipe pile 8 can be reduced. It is possible to realize shortening and reduction of material cost.

  The self-sediment prevention method for steel pipe piles to which the present invention is applied particularly connects the guide frame 72 to the guide pile 71 and the steel pipe pile 8 placed in the seabed ground 9 in the pile driving process, and the floating body portion 2 and the guide frame. 72, in the state where the lower end portion 8u of the steel pipe pile 8 is separated from the bottom surface portion 81u of the root hardening portion 81, the position of the steel pipe pile 8 is maintained and the fluidized solidified material is consolidated, thereby introducing the lead pile 71 and Since the load on the guide frame 72 is reduced, the number of steel pipe piles 8 that can be connected to one guide frame 72 is increased, and the number of guide piles 71 and guide frames 72 can be reduced, construction of the solidified steel pipe pile 8 It is possible to reduce the construction time of the lead pile 71 and the lead frame 72 and reduce the material construction cost.

  The self-settlement prevention method for steel pipe piles to which the present invention is applied is, in particular, by carrying out a removal step of removing the self-sediment prevention structure 7 of the steel pipe piles after consolidating the fluidized solidified material filled in the root-solidified portion 81. Since the steel pipe pile self-sink prevention structure 7 can be collected and reused, it is possible to reduce material construction costs.

  In addition, “substantially constant” in the above description is used within the range of the maximum particle size or less of a soil cement or the like that becomes a fluid solidifying material.

  As mentioned above, although the example of embodiment of this invention was demonstrated in detail, all the embodiment mentioned above showed only the example of actualization in implementing this invention, and these are the technical aspects of this invention. The range should not be interpreted in a limited way.

DESCRIPTION OF SYMBOLS 1: Self-sediment prevention apparatus 2 of steel pipe pile 2: Floating body part 2a: 1st connection part 2b: 2nd connection part 20: Hollow part 20s: Space 21: Intake / exhaust part 21a: Intake / exhaust port 21b for gas: Discharge port 21c for liquid: Liquid Suction port 3: Connecting jig 4: Restraining material 41: Anchor 5: Buffer material 60: Sensor part 61a: First water pressure gauge 61b: Second water pressure gauge 62: Position information device 7: Self-sink prevention structure 71 for steel pipe piles: Lead pile 72: Lead frame 8: Steel pipe pile 8a: Connection portion 8u: Lower end portion 81: Rooting portion 81u: Bottom portion 9: Submarine ground 91: Seawater X: First direction Y: Second direction Z: Height direction

Claims (11)

A steel pipe pile self-sink prevention device for preventing the steel pipe pile self-sink,
Floating in seawater, equipped with a floating body connected to the steel pipe pile,
The floating body is connected in a state where the lower end portion of the steel pipe pile provided in the root consolidation portion filled with the fluidized solidification material in the seabed ground is separated from the bottom surface portion of the root consolidation portion. A device for preventing self-sedimentation of a steel pipe pile, characterized by transmitting buoyancy to the steel pipe pile and maintaining the position of the steel pipe pile. And further comprising one or a plurality of restraining materials connected to the floating body and the anchor placed in the seabed ground,
2. The restraint member transmits a tensile force generated by the buoyancy to the connected floating body portion, and keeps the distance from the seabed ground surface to the floating body portion substantially constant. The self-sedimentation prevention apparatus of the steel pipe pile of description. The floating body portion has a highly airtight space and an intake / exhaust portion for sucking and discharging fluid inside the space,
The steel pipe pile self-sediment prevention device according to claim 1 or 2, wherein the suction / discharge section controls the buoyancy of the floating body section by sucking and discharging the fluid inside the space. A sensor unit for measuring a position in the height direction of the floating body unit;
The intake / exhaust part is configured to absorb and exhaust the fluid inside the space based on the measurement result of the sensor part, and to keep the distance from the seabed ground surface to the floating body part substantially constant. The self-sediment prevention device for steel pipe piles according to claim 3. The sensor unit includes at least one of a water pressure meter that measures a water pressure acting on the floating body part and a water pressure on the seabed ground surface, and a position information device that measures an altitude of the floating body part. The self-sediment prevention device for steel pipe piles according to claim 4. It further comprises a cushioning material provided between the floating body part and the steel pipe pile,
The said buffer material prevents rolling of the said steel pipe pile, The self-sediment prevention apparatus of the steel pipe pile of any one of Claims 1-5 characterized by the above-mentioned. A steel pipe pile self-sink prevention structure for preventing the steel pipe pile self-sink,
A steel pipe pile self-sink prevention device that floats in seawater and has a floating body connected to the steel pipe pile, a guide pile placed in the seabed ground, and a guide frame connected to the steel pipe pile and the guide pile. ,
The floating body part transmits buoyancy to the steel pipe pile to be connected,
In the state where the floating body part and the guide frame are spaced apart from the bottom part of the rooting part, the lower end part of the steel pipe pile provided in the rooting part filled with a fluidized solidifying material in the seabed ground, A structure for preventing self-sinking of a steel pipe pile, characterized by holding the position of the steel pipe pile. A steel pipe pile self-sink prevention method for preventing the steel pipe pile self-sink,
It is equipped with a pile driving process to install a steel pipe pile self-sink prevention device and drive the steel pipe pile into the seabed ground,
The steel pipe pile self-sediment prevention device has a floating body part floating in seawater,
In the pile driving step, the steel pipe pile is connected to the floating body part, and the lower end part of the steel pipe pile provided in the rooting part filled with the fluidized solidifying material in the seabed ground is connected to the rooting part. A method for preventing self-sedimentation of a steel pipe pile, characterized in that the position of the steel pipe pile is maintained while being separated from the bottom surface portion, and the fluidized solidifying material is consolidated. The said pile driving process connects a restraint material to the anchor casted in the said floating body part and seabed ground, and keeps the distance from a seabed ground surface to the said floating body part substantially constant. Self-sink prevention method for steel pipe piles. The floating body portion has a highly airtight space, and an intake / exhaust portion for sucking and exhausting fluid inside the space,
9. The steel pipe pile according to claim 8, wherein the pile driving step sucks and discharges the fluid inside the space by the suction and discharge portion, and keeps a distance from the seabed ground surface to the floating body portion substantially constant. Self-sink prevention method. In the pile driving step, a guide frame is connected to the guide pile and the steel pipe pile placed in the seabed ground, and the lower end portion of the steel pipe pile is a bottom surface portion of the rooting portion in the floating body portion and the guide frame. The steel pipe pile self-sink prevention method according to claim 8, wherein the steel pipe pile position is maintained in a state of being separated from the steel pipe pile.

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