JP2014237976A - Construction method of tide embankment, double steel pipe, and superstructure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction method of a tide embankment, a double steel pipe, and a superstructure capable of suppressing an increase in manufacturing cost and constructing a superstructure having a sufficient bearing force without increasing the board thickness of an outer steel pipe and an inner steel pipe more than needed and without making the materials of the outer steel pipe and the inner steel pipe high strength more than needed.SOLUTION: This invention relates to a double steel pipe 1 used as the foundation pillar of a superstructure 5. An outer steel pipe 2 installed in a ground 7 and at the same time boring the ground 7 and an inner steel pipe 3 installed inside the outer steel pipe 2 are included. The superstructure 5 is constructed above the outer steel pipe 2 and the inner steel pipe 3 under such a state that a material cured with time 11 is filled between the inner steel pipe 3 and the outer steel pipe 2 while having an internal space A of the inner steel pipe 3 hollow.

Description

  The present invention relates to a tide embankment, a double steel pipe used as a foundation pile of an upper structure, and a construction method of an upper structure in which the double steel pipe is used as a foundation pile.

  Conventionally, in order to effectively resist the seismic force acting on the upper structure, a steel pipe pile is sometimes used as the foundation pile of the upper structure. For example, the footing and the steel pipe pile disclosed in Patent Document 1 are sometimes used. A joint structure has been proposed.

  The joint structure between the footing and the steel pipe pile disclosed in Patent Document 1 includes a footing provided at the lower part of the column base or the pier, and a steel pipe pile installed at the lower part of the footing to support the structure. A footing and a steel pipe pile are joined by the provided connection part steel pipe.

  The joint structure between the footing and the steel pipe pile disclosed in Patent Document 1 is such that the upper end side of the connection part steel pipe is inserted into the lower end part of the footing, and the lower end side of the connection part steel pipe is inserted into the upper end part of the steel pipe pile. By filling the steel pipe and the steel pipe pile with concrete, the rigidity of the foundation pile composed of the connection portion steel pipe and the steel pipe pile is improved.

JP 2001-159142 A

  However, the joint structure of the footing and the steel pipe pile disclosed in Patent Document 1 is provided with a connection steel pipe serving as an inner steel pipe inside the steel pipe pile serving as an outer steel pipe, and between the outer steel pipe and the inner steel pipe. The foundation pile is constituted by filling the gap formed and the inside of the inner steel pipe with concrete, and the rigidity of the foundation pile is remarkably increased as compared with the surrounding ground.

  For this reason, since the rigidity of this foundation pile increases remarkably compared with the surrounding ground, the joint structure of the footing and the steel pipe pile disclosed in Patent Document 1 is used when the seismic force acts on the upper structure. Compared to other stress-sharing materials such as the surrounding ground where the foundation pile is driven, the cross-sectional force that acts due to seismic force, etc. will be concentrated on this foundation pile, causing a large stress on the foundation pile was there.

  Moreover, since the joint structure of the footing and steel pipe pile disclosed by patent document 1 needs to resist the big stress which generate | occur | produces in this foundation pile, the steel pipe pile used as the outer steel pipe of this foundation pile, There has been a problem that the manufacturing cost of this foundation pile will increase by increasing the plate thickness of the connecting portion steel pipe to be the steel pipe and increasing the material strength.

  Furthermore, the joint structure of the footing and steel pipe pile disclosed in Patent Document 1 increases the plate thickness of the steel pipe pile and the connection part steel pipe, and the strength of the material is increased, so that the rigidity of this foundation pile is compared with the surrounding ground. As a result, the cross-sectional force acting due to seismic force or the like is further concentrated on the foundation pile, which causes a problem that a greater stress is generated on the foundation pile.

  Therefore, the present invention has been devised in view of the above-mentioned problems, and the object of the present invention is to increase the outer steel pipe and the inner steel pipe without increasing the thickness of the outer steel pipe and the inner steel pipe more than necessary. Without increasing the strength of the material more than necessary, the increase in the manufacturing cost of the double steel pipe can be suppressed, and a tide embankment capable of constructing a superstructure with sufficient supporting force, the double steel pipe, It is in providing the construction method of a superstructure.

  The tide embankment of the first invention is a tide embankment that is constructed in the coastal area to prevent inundation damage in the inland area, and includes a double steel pipe provided as a foundation pile on the ground on the sea side and the inland side, and the sea side and inland The double steel pipe includes an outer steel pipe provided on the ground at the same time as excavating the ground, and an inner part provided on the inner side of the outer steel pipe. The inner steel pipe has a hollow inner space and is filled with a time-hardening material between the inner steel pipe and the outer steel pipe.

  The seawall of the second invention is characterized in that, in the first invention, the cross-section connecting beam has a sheath pipe through which the foundation pile is inserted, and is arranged from the ground on the sea side to the ground on the inland side. And

  A double steel pipe according to a third aspect of the present invention is a double steel pipe used as a foundation pile of an upper structure, and includes an outer steel pipe provided on the ground simultaneously with excavating the ground, and an inner steel pipe provided on the inner side of the outer steel pipe. The upper structure is constructed above the outer steel pipe and the inner steel pipe, with the inner space of the inner steel pipe being hollow and filled with a time-hardening material between the inner steel pipe and the outer steel pipe. It is characterized by being.

  The double steel pipe of the fourth invention is the double steel pipe according to the third invention, wherein either one or both of the outer steel pipe and the inner steel pipe are either one or both of the inner surface of the outer steel pipe and the outer surface of the inner steel pipe. A dive is provided in a predetermined range of one or both of the upper end and the lower end of the steel pipe and the inner steel pipe.

  A double steel pipe according to a fifth aspect of the present invention is the double steel pipe according to the fourth aspect of the present invention, wherein the gibber uses a protruding steel pipe for one or both of the outer steel pipe and the inner steel pipe, or the inner surface of the outer steel pipe and the inner steel pipe It is characterized by being provided by welding a bar-shaped steel member such as a reinforcing bar to either one or both of the outer surfaces of.

  In any one of the third to fifth inventions, the double steel pipe of the sixth invention is provided substantially horizontally or inclined at any one or both of the upper and lower ends of the outer steel pipe and the inner steel pipe. A rib plate is provided.

  The double steel pipe of the seventh invention is any one of the third to sixth inventions, wherein the height of the top end of the outer steel pipe is substantially the same as the height of the top end of the inner steel pipe. .

  The double steel pipe of the eighth invention is the fourth invention or the fifth invention, wherein the height of the top end of the outer steel pipe is substantially the same as the height of the top end of the inner steel pipe. The outer steel pipe and the inner steel pipe are provided at one or both of the upper end portion and the lower end portion thereof.

  The double steel pipe of the ninth invention is any one of the third to sixth inventions, wherein the height of the top end of the outer steel pipe is lower than the height of the top end of the inner steel pipe.

  The double steel pipe of the tenth invention is the fourth invention or the fifth invention, wherein the height of the top end of the outer steel pipe is lower than the height of the top end of the inner steel pipe. It is provided in any one or both of the inner surface of the upper end part of an outer steel pipe, and the outer surface adjacent to the upper end part of the said outer steel pipe in the said inner steel pipe.

  The double steel pipe of the eleventh invention is the sixth invention, wherein the height of the top end of the outer steel pipe is lower than the height of the top end of the inner steel pipe, and the rib plate is formed from the outer surface of the inner steel pipe. The outer steel pipe is provided on the inner surface or outer surface of the outer steel pipe.

  The double steel pipe of the twelfth invention is characterized in that, in any of the third invention to the sixth invention, the height of the top end of the outer steel pipe is higher than the height of the top end of the inner steel pipe.

  The double steel pipe of the thirteenth invention is the fourth invention or the fifth invention, in which the height of the top end of the outer steel pipe is higher than the height of the top end of the inner steel pipe. It is provided in any one or both of the outer surface of the upper end part of an inner steel pipe, and the inner surface adjacent to the upper end part of the said inner steel pipe in the said outer steel pipe.

  The double steel pipe of the fourteenth invention is the sixth invention, wherein the height of the top end of the outer steel pipe is higher than the height of the top end of the inner steel pipe, and the rib plate extends from the inner surface of the outer steel pipe. It is provided to be installed on the inner surface or the outer surface of the inner steel pipe.

  A double steel pipe according to a fifteenth aspect of the invention is any one of the third through fourteenth aspects, wherein the outer steel pipe is provided with a drilling bit at a lower end portion for excavating the ground.

  The double steel pipe of the sixteenth aspect of the invention is the invention according to any one of the third to fifteenth aspects of the invention, wherein the inner steel pipe is spaced by a predetermined distance from the inner surface of the outer steel pipe by attaching a perforated steel plate to the outer surface. A member is provided.

  A double steel pipe according to a seventeenth aspect of the present invention is directed to any one of the third to sixteenth aspects, wherein the outer steel pipe is provided with the inner steel pipe on the inner side and is directed from the lower end portion of the inner steel pipe toward the inner surface of the outer steel pipe. In the state where the tapered member is provided, the ground is excavated and simultaneously provided on the ground.

  In the double steel pipe of the eighteenth invention, in any one of the third to seventeenth inventions, in the hollow internal space of the inner steel pipe, the increase in rigidity of the outer steel pipe and the inner steel pipe is suppressed. Non-stress transmitting material is accommodated.

  In the double steel pipe of the nineteenth aspect of the invention, in any one of the third to eighteenth aspects of the invention, the hollow inner space of the inner steel pipe has a lapse of time only at the lower end portion of the inner steel pipe that is in the vicinity of the supporting ground layer. It is characterized by being filled with a curable material.

  The double steel pipe of the twentieth invention is the double steel pipe of the nineteenth invention, wherein the inner steel pipe is a steel pipe with a projection protruding from the inner surface of the lower end portion, or a bar-shaped steel member such as a reinforcing bar is welded to the inner surface of the lower end portion. In this case, a gibber is provided.

  The double steel pipe of the twenty-first aspect of the invention is any one of the third to eighteenth aspects of the present invention, wherein the hollow internal space of the inner steel pipe has a circumferential direction in one or both of the inner steel pipe and the outer steel pipe. The time-curable material is filled only in the range in which the stress is generated.

  The construction method of the upper structure of the 22nd invention is a construction method of an upper structure in which a double steel pipe is used as a foundation pile, and at the same time as excavating the ground with an outer steel pipe provided with a drilling bit at the lower end, An outer steel pipe installation step in which an outer steel pipe is provided on the ground; an inner steel pipe installation step in which an inner steel pipe is provided inside the outer steel pipe and a time-hardening material is filled between the inner steel pipe and the outer steel pipe; And a structure construction step of constructing an upper structure above the outer steel pipe and the inner steel pipe in a state where the internal space of the steel pipe is hollow.

  The construction method of the superstructure of the 23rd invention is a construction method of a superstructure in which a double steel pipe is used as a foundation pile, and an outer steel pipe in which an excavation bit is provided at the lower end and an inner steel pipe is provided on the inner side. A double steel pipe installation step in which the outer steel pipe and the inner steel pipe are provided on the ground and the time-hardening material is filled between the inner steel pipe and the outer steel pipe, And a structure construction step of constructing an upper structure above the outer steel pipe and the inner steel pipe in a state where the space is hollow.

  According to a twenty-fourth aspect of the present invention, in the twenty-second or twenty-third aspect, in the structure construction step, the inner steel pipe that is in the vicinity of the supporting ground layer is formed in the hollow inner space of the inner steel pipe. Only the lower end portion is filled with the time-curable material.

  According to a 25th aspect of the present invention, there is provided a method for constructing an upper structure in the 22nd or 23rd aspect, wherein in the structure construction step, either one of the inner steel pipe and the outer steel pipe is provided in a hollow internal space of the inner steel pipe. Alternatively, the time-curable material is filled only in a range where circumferential stress is generated in both.

  According to a twenty-sixth aspect of the present invention, there is provided a method for constructing an upper structure according to any one of the twenty-second to twenty-fifth aspects, wherein in the structure construction step, the outer steel pipe and the inner steel pipe are placed in a hollow inner space of the inner steel pipe. In order to suppress an increase in rigidity, an upper structure is constructed above the outer steel pipe and the inner steel pipe in a state in which a non-stress transmitting material is accommodated.

  According to the first to twenty-first inventions, since the inner space of the inner steel pipe is made hollow and the upper structure is constructed above the outer steel pipe and the inner steel pipe, the overall rigidity of the outer steel pipe and the inner steel pipe is Compared to the ground, it is possible to suppress a significant increase, to suppress the cross-sectional force generated by seismic force, etc., and to reduce the stress generated in the outer steel pipe and inner steel pipe compared to the surrounding ground It becomes possible.

  Further, according to the first to twenty-first inventions, the thickness of the outer steel pipe and the inner steel pipe is not increased more than necessary, and the material of the outer steel pipe and the inner steel pipe is not increased more than necessary. The increase in the manufacturing cost of the double steel pipe to which the invention is applied can be suppressed, and an upper structure having a sufficient support force can be constructed while suppressing the increase in the construction cost.

  In particular, according to the fifteenth aspect, it is possible to provide the outer steel pipe on the ground at the same time as excavating the ground with the outer steel pipe provided with the excavation bit at the lower end portion for excavating the ground.

  In particular, according to the sixteenth aspect, the tips of the plurality of spacing members are brought into contact with the inner surface of the outer steel pipe, so that the outer surface of the inner steel pipe and the inner surface of the outer steel pipe are spaced at a predetermined distance along the circumference. Is ensured, and a gap portion can be formed between the outer surface of the inner steel pipe and the inner surface of the outer steel pipe.

  In particular, according to the seventeenth invention, it is possible to reduce the penetration resistance when the outer steel pipe and the inner steel pipe are simultaneously buried in the ground by the tapered member inclined so as to expand the diameter in the direction orthogonal to the pipe axis. .

  In particular, according to the eighteenth aspect, the non-stress transmitting material such as earth and sand is only accommodated in the inner space of the inner steel pipe, and does not contribute to the increase in rigidity of the outer steel pipe and the inner steel pipe. While suppressing the increase in rigidity, it is not necessary to dispose of non-stress transmitting materials such as earth and sand outside, and it is possible to suppress the increase in environmental cost required for disposal of non-stress transmitting materials such as earth and sand. Become.

  In particular, according to the nineteenth and twentieth inventions, the time-curable material is provided in the inner space of the inner steel pipe only in the portion embedded in the surrounding support ground layer having a large rigidity and the lower end portion of the inner steel pipe in the vicinity thereof. By being filled, it becomes possible to ensure and improve the integrity at the lower end of the outer steel pipe and the inner steel pipe.

  In particular, according to the twenty-first invention, while suppressing the increase in the overall rigidity of the outer steel pipe and the inner steel pipe, circumferential stress is generated in the outer steel pipe and the inner steel pipe by the ground reaction force, etc. In addition, it is possible to ensure and improve the integrity of the lower end portion of the outer steel pipe and the inner steel pipe only in a range where there is a concern that the inner steel pipe is deformed so as to be crushed.

  According to the twenty-second invention to the twenty-sixth invention, since the inner space of the inner steel pipe is made hollow and the upper structure is constructed above the outer steel pipe and the inner steel pipe, the overall rigidity of the outer steel pipe and the inner steel pipe is Compared to the ground, it is possible to suppress a significant increase, to suppress the cross-sectional force generated by seismic force, etc., and to reduce the stress generated in the outer steel pipe and inner steel pipe compared to the surrounding ground It becomes possible.

  Further, according to the twenty-second to twenty-sixth aspects of the present invention, the thickness of the outer steel pipe and the inner steel pipe is not increased more than necessary, and the material of the outer steel pipe and the inner steel pipe is not increased more than necessary. The increase in the manufacturing cost of the double steel pipe to which the invention is applied can be suppressed, and an upper structure having a sufficient support force can be constructed while suppressing the increase in the construction cost.

  In particular, according to the twenty-third invention, in the double steel pipe installation step, the outer steel pipe and the inner steel pipe can be simultaneously buried in the ground while the ground is excavated with the outer steel pipe.

  In particular, according to the twenty-fourth invention, the internal space of the inner steel pipe is filled with the time-hardening material only at the lower portion of the inner steel pipe that is embedded in the surrounding support ground layer having a large rigidity and the vicinity thereof, It becomes possible to ensure and improve the integrity at the lower end of the outer steel pipe and the inner steel pipe.

  In particular, according to the twenty-fifth aspect, while suppressing an increase in the overall rigidity of the outer steel pipe and the inner steel pipe, circumferential stress is generated in the outer steel pipe and the inner steel pipe by the ground reaction force, and the outer steel pipe and Only in a range where there is a concern about an adverse effect such as deforming the inner steel pipe so as to be crushed, the rigidity of the outer steel pipe and the inner steel pipe can be partially improved as necessary.

  In particular, according to the twenty-sixth invention, the non-stress transmitting material such as earth and sand is only accommodated in the inner space of the inner steel pipe, and does not contribute to the increase in rigidity of the outer steel pipe and the inner steel pipe. While suppressing the increase in rigidity, it is not necessary to dispose of non-stress transmitting materials such as earth and sand outside, and it is possible to suppress the increase in environmental cost required for disposal of non-stress transmitting materials such as earth and sand. Become.

It is a perspective view which shows the upper structure which uses a double steel pipe to which this invention is applied as a foundation pile. It is a front view which shows the double steel pipe and superstructure to which this invention is applied. (A) is an enlarged side view which shows a part of outer steel pipe of the double steel pipe to which this invention is applied, (b) is an enlarged side view which shows the modification. (A) is a side sectional view showing a part of a double steel pipe to which the present invention is applied, and (b) is a bottom view of the double steel pipe to which the present invention is applied. It is a partially broken side view which shows the double steel pipe and superstructure of 1st Embodiment to which this invention is applied. (A) is a side view showing a state before driving the outer steel pipe into the ground in the outer steel pipe installation step of the construction method of the superstructure of the first embodiment to which the present invention is applied, and (b) is an outer view. It is a side view which shows the state after driving a steel pipe into the ground. (A) is a side view which shows the state before providing an inner steel pipe inside an outer steel pipe in the inner steel pipe installation process of the construction method of the superstructure of 1st Embodiment to which this invention is applied, (b) These are side views which show the state after providing the inner steel pipe inside the outer steel pipe. (A) is the side view which shows the state which constructed the seawall above the outer steel pipe and the inner steel pipe in the structure construction process of the construction method of the upper structure of the first embodiment to which the present invention is applied. b) is a side view showing a state in which the footing is constructed. (A) is a side view which shows the state which fills a time-hardening material only in the lower end part of an outer steel pipe in an outer steel pipe installation process, (b) is only the lower end part of an inner steel pipe in an inner steel pipe installation process. It is a side view which shows the state filled with a time-hardenable material. (A) is a side view showing a state in which a non-stress transmitting material such as excavation residual soil is accommodated in the inner space of the inner steel pipe in the structure construction process, and (b) is a circumference around the outer steel pipe and the inner steel pipe. It is a side view which shows the state which fills a time-curable material only to the range which concerns about generation | occurrence | production of the stress of a direction. It is a partially broken side view which shows the double steel pipe and superstructure of 2nd Embodiment to which this invention is applied. (A) is side sectional drawing which shows a part of double steel pipe of 2nd Embodiment to which this invention is applied, (b) is the bottom face of the double steel pipe of 2nd Embodiment to which this invention is applied. FIG. (A) is a side view showing a state before driving the outer steel pipe and the inner steel pipe into the ground in the double steel pipe installation step of the construction method of the superstructure of the second embodiment to which the present invention is applied, (b ) Is a side view showing a state after the outer steel pipe and the inner steel pipe are driven into the ground. (A) is a side view showing a state in which the internal space of the inner steel pipe is hollow in the structure construction step, (b) is a side view showing a state in which a non-stress transmitting material is accommodated, (C) is a side view showing a state in which a time-curable material is filled only in a predetermined range. It is side sectional drawing which shows the dowel of the double steel pipe of 3rd Embodiment to which this invention is applied. It is a side view which shows the rib plate of the double steel pipe of 4th Embodiment to which this invention is applied. It is side sectional drawing which shows a rib plate when the height of the top end of the outer steel pipe in the double steel pipe of 4th Embodiment to which this invention is applied becomes lower than the height of the top end of an inner steel pipe. It is side sectional drawing which shows a rib plate when the height of the top end of the outer steel pipe in the double steel pipe of 4th Embodiment to which this invention is applied becomes higher than the height of the top end of an inner steel pipe. (A) is a side view which shows the state of the stress which generate | occur | produces in the double steel pipe to which this invention is applied, (b) is a side view which shows the state of the stress which generate | occur | produces in the conventional double steel pipe.

  Hereinafter, the form for implementing the double steel pipe 1 to which this invention is applied is demonstrated in detail, referring drawings.

  As shown in FIG. 1, the double steel pipe 1 to which the present invention is applied is buried as a foundation pile in the ground 7 in order to support an upper structure 5 such as a seawall 53 that blocks tsunami and storm surge. is there.

  The seawall 53 to which the present invention is applied is installed on the double steel pipe 1 to which the present invention is applied as the foundation pile on the ground 7 on the sea side and the inland side, and on the foundation pile on the ground 7 on the sea side and the inland side. A cross-sectional connecting beam 51 and a wall body are provided. The cross-direction connecting beam 51 has a sheath tube 52 through which a foundation pile is inserted, and is disposed from the ground 7 on the sea side to the ground 7 on the inland side.

  In the double steel pipe 1 to which the present invention is applied, as shown in FIG. 2, the height of the top end of the outer steel pipe 2 is lower than the height of the top end of the inner steel pipe 3. Some are higher than the height, and others are substantially the same as the height of the top of the inner steel pipe 3.

  The double steel pipe 1 to which the present invention is applied includes an outer steel pipe 2 provided on the ground 7 at the same time as excavating the ground 7 and an inner steel pipe 3 provided on the inner side of the outer steel pipe 2 in the first embodiment. The upper structure 5 is constructed above the ground 7 in which the 2 and the inner steel pipe 3 are embedded.

  As shown in FIG. 3A, the outer steel pipe 2 is a steel pipe having a substantially circular cross section formed with a predetermined inner diameter, and excavating a plurality of cemented carbides along the circumference of the lower end 2c. A bit 21 is attached. The outer steel pipe 2 is not limited to this, and in a modified example, as shown in FIG. 3B, a short steel pipe 29 to which a plurality of excavation bits 21 are attached is connected to the lower end portion 2c of the outer steel pipe 2 by welding or the like. May be.

  As shown in FIG. 4, the inner steel pipe 3 is a steel pipe having a substantially circular cross section formed with an outer diameter smaller than the inner diameter of the outer steel pipe 2, and is provided inside the outer steel pipe 2. An internal space A surrounded by the inner surface 3b of 3 is formed.

  As shown in FIG. 4A, the inner steel pipe 3 is provided with a plurality of gap retaining members 31 such as perforated steel plates on the outer surface 3 a of the inner steel pipe 3. In the inner steel pipe 3, the base end portion 31 a of the interval holding member 31 is attached to the outer surface 3 a of the inner steel pipe 3 by welding or the like, and a plurality of interval holding members 31 are provided along the circumference of the outer surface 3 a of the inner steel pipe 3. Thus, the tip 31b of the spacing member 31 is brought into contact with the inner surface 2b of the outer steel pipe 2.

  As shown in FIG. 4 (b), the inner steel pipe 3 has the outer surface 3 a of the inner steel pipe 3 and the outer steel pipe 2 by the tips 31 b of the plurality of spacing members 31 being in contact with the inner surface 2 b of the outer steel pipe 2. The inner surface 2b of the inner steel pipe 3 is spaced apart from the inner surface 2b with a predetermined interval, and a gap G is formed between the outer surface 3a of the inner steel pipe 3 and the inner surface 2b of the outer steel pipe 2.

  As shown in FIG. 5, the inner steel pipe 3 has a hollow inner space A, and a mortar, cement milk, or the like is formed in a gap G formed between the outer surface 3 a of the inner steel pipe 3 and the inner surface 2 b of the outer steel pipe 2. The upper structure 5 is constructed above the outer steel pipe 2 and the inner steel pipe 3 in a state filled with the time-curable material 11.

  In the gap G, the protrusion 12 can be formed on one or both of the outer surface 3 a of the inner steel pipe 3 and the inner surface 2 b of the outer steel pipe 2. The protrusion 12 may be formed when the outer steel pipe 2 or the inner steel pipe 3 is rolled, may be formed by welding a reinforcing bar or the like, and is further formed by placing a bead by welding. May be.

  The gap G is formed by engaging the protrusion 12 formed on the outer surface 3a of the inner steel pipe 3 and the inner surface 2b of the outer steel pipe 2 with the time-hardening material 11 hardened in the gap G, thereby The inner steel pipe 3 can be fixed so as not to deviate from each other in the pipe axis direction X, and the outer steel pipe 2 and the inner steel pipe 3 can be firmly integrated.

  The gap portion G is formed by providing a gap holding member 31 such as a plurality of perforated steel plates on the outer surface 3 a of the inner steel pipe 3, so that the gap portion G has a hole opening portion in the time-curable material 11 cured in the gap portion G. By locking 31c, the outer steel pipe 2 and the inner steel pipe 3 can be fixed so as not to deviate from each other in the pipe axis direction X, and the outer steel pipe 2 and the inner steel pipe 3 can be firmly integrated. It becomes possible.

  The construction method of the superstructure 5 to which the present invention is applied uses the double steel pipe 1 to which the present invention is applied in the first embodiment. As shown in FIGS. 6, 7, and 8, the construction method of the superstructure 5 to which the present invention is applied includes an outer steel pipe installation process that is performed first, an inner steel pipe installation process that is performed next, and a final process. The structure construction process implemented in (1).

  In the outer steel pipe installation step, as shown in FIG. 6A, the ground 7 is excavated with a plurality of excavation bits 21 provided at the lower end portion 2c of the outer steel pipe 2 while rotating the outer steel pipe 2 in the circumferential direction. The outer steel pipe 2 is embedded in the ground 7, and the outer surface 2 a of the outer steel pipe 2 is supported by circumferential friction with the ground 7. At this time, in the outer steel pipe installation step, as shown in FIG. 6 (b), the earth and sand inside the outer steel pipe 2 is discharged by a hammaglab and the ground 7 is excavated by the outer steel pipe 2, and at the same time, The steel pipe 2 is provided, and the inner surface 2b of the outer steel pipe 2 is cleaned.

  In the inner steel pipe installation step, as shown in FIG. 7A, the inner steel pipe 3 is inserted and provided inside the outer steel pipe 2 provided on the ground 7. In the inner steel pipe installation step, as shown in FIG. 7 (b), the inner steel pipe 3 is formed at a predetermined distance from the inner surface 2b of the outer steel pipe 2 by a plurality of spacing members 31 provided on the outer surface 3a of the inner steel pipe 3. The gap G is filled with the time-curable material 11.

  In the structure construction step, as shown in FIG. 8A, the upper structure 5 is constructed above the outer steel pipe 2 and the inner steel pipe 3 in a state where the inner space A of the inner steel pipe 3 is hollow. For example, the upper structure 5 is formed by inserting the outer steel pipe 2 and the inner steel pipe 3 through a sheath pipe 52 provided in the cross-section connecting beam 51 and extending the upper end 2d of the outer steel pipe 2 upward from the ground 7. Is constructed on the ground 7 by being inserted into the inside of the seawall 53 using precast concrete.

  The upper structure 5 is not limited to this, and the upper end 2d of the outer steel pipe 2 is inserted into the footing 54 using precast concrete, as shown in FIG. The footing 54 to be placed may be constructed. Further, the upper structure 5 is not limited to the one using precast concrete, and may be constructed by spot-cast concrete or the like.

  The construction method of the upper structure 5 to which the present invention is applied is as follows. In the outer steel pipe installation step, as shown in FIG. 9A, the outer steel pipe 2 is provided on the ground 7 at the same time as excavating the ground 7 with the outer steel pipe 2. The time-curable material 11 can be filled inside the outer steel pipe 2 only at the lower end portion 2c of the outer steel pipe 2 embedded in the supporting ground layer 7a and in the vicinity of the supporting ground layer 7a.

  At this time, the construction method of the upper structure 5 to which the present invention is applied is such that, in the inner steel pipe installation step, as shown in FIG. 9 (b), the inner steel pipe 3 is provided inside the outer steel pipe 2, and the supporting ground layer 7a. The inner space A of the lower end portion 3c of the inner steel pipe 3 that is driven into is filled with the time-curable material 11 and cured. Thereby, the construction method of the upper structure 5 to which the present invention is applied, in the structure construction process, in the portion embedded in the surrounding support ground layer 7a having a large rigidity and the lower end portion 3c of the inner steel pipe 3 in the vicinity thereof. Only when the internal space A of the inner steel pipe 3 is filled with the time-hardening material 11, it becomes possible to ensure and improve the integrity of the lower end 2c of the outer steel pipe 2 and the lower end 3c of the inner steel pipe 3.

  The construction method of the upper structure 5 to which the present invention is applied is such that, as shown in FIG. 10 (a), in the structure construction process, non-stress transmission such as excavation residual soil made of earth and sand discharged in the outer steel pipe installation process The upper structure 5 can be constructed above the outer steel pipe 2 and the inner steel pipe 3 in a state where the material 13 is accommodated in the inner space A of the inner steel pipe 3.

  At this time, the non-stress transmitting material 13 such as earth and sand is only accommodated in the inner space A of the inner steel pipe 3, and does not contribute to the increase in rigidity of the outer steel pipe 2 and the inner steel pipe 3, so that the outer steel pipe 2 and the inner steel pipe 3 increases the increase in rigidity. Thereby, the construction method of the superstructure 5 to which the present invention is applied does not require discarding the non-stress transmitting material 13 to the outside, and suppresses an increase in environmental cost necessary for discarding the non-stress transmitting material 13. It becomes possible to do.

  The construction method of the upper structure 5 to which the present invention is applied is such that, in the structure construction step, the outer steel pipe 2 and the inner steel pipe 3 are connected to the sheath pipe 52 provided in the cross-section connecting beam 51 as shown in FIG. It is possible to fill the internal space A of the inner steel pipe 3 with the time-curable material 11 and harden it only at the joint portion 55 through which is inserted. As a result, the construction method of the superstructure 5 to which the present invention is applied suppresses the increase in the overall rigidity of the outer steel pipe 2 and the inner steel pipe 3 while suppressing the vicinity of the design ground surface (if the ground surface is the design ground surface). For example, the outer steel pipe 2 and the inner steel pipe 3 are stressed in the circumferential direction by the ground reaction force such as the vicinity of the ground surface) or the site where the cross-sectional force is concentrated, such as the joint 55, etc. It is possible to ensure and improve the integrity of the outer steel pipe 2 and the inner steel pipe 3 only in the range where there is a concern about adverse effects such as deformation such as crushing.

  Next, a second embodiment of the double steel pipe 1 to which the present invention is applied will be described. 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. 11, the double steel pipe 1 to which the present invention is applied has an inner steel pipe 3 provided in advance inside the outer steel pipe 2 in the second embodiment, and the outer steel pipe 2 and the inner steel pipe 3 excavate the ground 7. At the same time, it is provided on the ground 7 and the upper structure 5 is constructed above the ground 7.

  As shown in FIG. 12, the outer steel pipe 2 has an inner steel pipe 3 provided on the inner side, and expands in the pipe axis orthogonal direction Y from the lower end portion 3 c of the inner steel pipe 3 toward the inner surface 2 b of the outer steel pipe 2. A taper member 22 is provided which is inclined and installed. The taper member 22 has a base end portion 22a attached to the lower end portion 3c of the inner steel pipe 3 by welding or the like, and a tip end portion 22b attached to the inner surface 2b of the outer steel pipe 2 by welding or the like.

  As shown in FIG. 11, the double steel pipe 1 to which the present invention is applied has a hollow inner space A of the inner steel pipe 3 and the outer surface 3 a of the inner steel pipe 3 and the outer steel pipe above the pipe axis direction X of the taper member 22. The upper structure 5 is constructed above the outer steel pipe 2 and the inner steel pipe 3 in a state in which the gap G formed between the inner surface 2b and the inner surface 2b is filled with the time-curable material 11.

  In the second embodiment, as shown in FIGS. 13 and 14, the construction method of the superstructure 5 to which the present invention is applied is the first double steel pipe installation step and the last structural construction. A process.

  In the double steel pipe installation step, as shown in FIG. 13 (a), the outer steel pipe 2 and the inner steel pipe 3 are rotated in the circumferential direction while the inner steel pipe 3 is previously provided inside the outer steel pipe 2. The ground 7 is excavated by a plurality of excavation bits 21 provided at the lower end 2 c of the steel pipe 2, the outer steel pipe 2 and the inner steel pipe 3 are embedded in the ground 7, and the outer surface 2 a of the outer steel pipe 2 is a circumferential surface with the ground 7. Supported by friction. At this time, in the double steel pipe installation step, as shown in FIG. 13 (b), the earth and sand inside the inner steel pipe 3 is discharged with a hammer magnet or the like, and the inner surface 3b of the inner steel pipe 3 is cleaned.

  In the double steel pipe installation step, the time-curable material 11 is filled into the gap G formed by being spaced apart from the inner surface 2b of the outer steel pipe 2 at a predetermined interval. The construction method of the superstructure 5 to which the present invention is applied is such that the penetration resistance when the outer steel pipe 2 and the inner steel pipe 3 are driven into the ground 7 is expanded in the pipe axis orthogonal direction Y in the double steel pipe installation step. It can be reduced by the taper member 22 inclined to the angle.

  In the structure construction step, as shown in FIG. 14A, the upper structure 5 is constructed above the outer steel pipe 2 and the inner steel pipe 3 in a state where the inner space A of the inner steel pipe 3 is hollow. Further, in the structure construction process, as shown in FIG. 14 (b), the non-stress transmitting material 13 such as earth and sand discharged in the double steel pipe installation process is accommodated in the internal space A of the inner steel pipe 3. Thus, the upper structure 5 can be constructed above the outer steel pipe 2 and the inner steel pipe 3. At this time, the non-stress transmitting material 13 is only accommodated in the inner space A of the inner steel pipe 3 and does not contribute to the increase in rigidity of the outer steel pipe 2 and the inner steel pipe 3, and the rigidity of the outer steel pipe 2 and the inner steel pipe 3 is increased. This suppresses the increase of. Thereby, the construction method of the superstructure 5 to which the present invention is applied does not require discarding the non-stress transmitting material 13 to the outside, and suppresses an increase in environmental cost necessary for discarding the non-stress transmitting material 13. It becomes possible to do.

  Furthermore, in the structure construction step, as shown in FIG. 14 (c), the inner steel pipe is provided only at the joint portion 55 in which the outer steel pipe 2 and the inner steel pipe 3 are inserted into the sheath pipe 52 provided in the cross-section connecting beam 51. 3 can be filled with the time-curable material 11 and cured. As a result, the construction method of the superstructure 5 to which the present invention is applied suppresses the increase in the overall rigidity of the outer steel pipe 2 and the inner steel pipe 3 while suppressing the vicinity of the design ground surface (if the ground surface is the design ground surface). For example, the outer steel pipe 2 and the inner steel pipe 3 are stressed in the circumferential direction by the ground reaction force such as the vicinity of the ground surface) or the site where the cross-sectional force is concentrated, such as the joint 55, etc. It is possible to ensure and improve the integrity of the outer steel pipe 2 and the inner steel pipe 3 only in the range where there is a concern about adverse effects such as deformation such as crushing.

  Next, a third embodiment of the double steel pipe 1 to which the present invention is applied will be described. 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. 15, in the double steel pipe 1 to which the present invention is applied, in the third embodiment, one or both of the outer steel pipe 2 and the inner steel pipe 3 are the inner surface 2 b of the outer steel pipe 2 and the inner steel pipe 3. At either one or both of the outer surfaces 3a, a diver 23 is provided in a predetermined range L in the upper end 2d of the outer steel pipe 2 or the upper end 3d of the inner steel pipe 3. The double steel pipe 1 to which the present invention is applied is not limited to this, and a diver 23 may be provided in a predetermined range L in the lower end 2c of the outer steel pipe 2 or the lower end 3c of the inner steel pipe 3.

  As for the gibber 23, a steel pipe with a protrusion is used for either one or both of the outer steel pipe 2 and the inner steel pipe 3, or either one or both of the inner surface 2b of the outer steel pipe 2 and the outer surface 3a of the inner steel pipe 3 are made of reinforcing steel or the like. It is provided by welding a rod-shaped steel member.

  As shown in FIG. 15A, the gibber 23 is at least the upper end portion 2 d of the outer steel pipe 2 when the height of the top end of the outer steel pipe 2 and the height of the top end of the inner steel pipe 3 are substantially the same. And the upper end 3d of the inner steel pipe 3 is provided on either one or both. Further, as shown in FIG. 15 (b), when the height of the top end of the outer steel pipe 2 is lower than the height of the top end of the inner steel pipe 3, the gibber 23 is at least the upper end of the outer steel pipe 2. It is provided on either or both of the inner surface 2b of the portion 2d and the outer surface 3a adjacent to the upper end portion 2d of the outer steel pipe 2 in the inner steel pipe 3. Further, as shown in FIG. 15 (c), when the height of the top end of the outer steel pipe 2 is higher than the height of the top end of the inner steel pipe 3, the gibber 23 is at least the upper end of the inner steel pipe 3. The outer surface 3a of the part 3d and the inner surface 2b adjacent to the upper end 3d of the inner steel pipe 3 in the outer steel pipe 2 are provided on one or both of them.

  As shown in FIG. 9 (b), the gibber 23 is a steel pipe with a protrusion protruding on the inner surface 3 b of the lower end portion 3 c of the inner steel pipe 3, or a rebar or the like on the inner surface 3 b of the lower end portion 3 c of the inner steel pipe 3. The rod-shaped steel member may be provided by welding. At this time, when the internal space A of the inner steel pipe 3 is filled with the time-curable material 11, the gibbel 23 ensures and improves the integrity of the lower end 2c of the outer steel pipe 2 and the lower end 3c of the inner steel pipe 3. Will be possible.

  Next, 4th Embodiment of the double steel pipe 1 to which this invention is applied is described. 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. 16, the double steel pipe 1 to which the present invention is applied is substantially horizontal horizontal rib plate 24 or inclined at the upper end 2 d of the outer steel pipe 2 or the upper end 3 d of the inner steel pipe 3 in the fourth embodiment. The inclined rib plate 25 is provided. The double steel pipe 1 to which the present invention is applied is not limited to this, and a substantially horizontal horizontal rib plate 24 or an inclined inclined rib plate 25 is provided at the lower end 2c of the outer steel pipe 2 or the lower end 3c of the inner steel pipe 3. May be.

  The horizontal rib plate 24 or the inclined rib plate 25 is provided, for example, by arranging 12 plate members in the circumferential direction of the outer steel pipe 2 and the inner steel pipe 3. As shown in FIG. 17, when the height of the top end of the outer steel pipe 2 is lower than the height of the top end of the inner steel pipe 3, the horizontal rib plate 24 or the inclined rib plate 25 has the outer surface of the inner steel pipe 3. 3a to the inner surface 2b or the outer surface 2a of the outer steel pipe 2 is provided. Further, as shown in FIG. 18, the horizontal rib plate 24 or the inclined rib plate 25 is configured such that the height of the top end of the outer steel pipe 2 is higher than the height of the top end of the inner steel pipe 3. The inner surface 2b of the inner steel pipe 3 is provided from the inner surface 2b to the outer surface 3a.

  In the double steel pipe 1 to which the present invention is applied, as shown in FIG. 19 (a), in any of the first to fourth embodiments, the inner space A of the inner steel pipe 3 is hollow, The upper structure 5 is constructed above the outer steel pipe 2 and the inner steel pipe 3. At this time, the double steel pipe 1 to which the present invention is applied can suppress the overall rigidity of the outer steel pipe 2 and the inner steel pipe 3 from being significantly increased as compared with the surrounding ground 7.

  On the other hand, as shown in FIG. 19 (b), the conventional double steel pipe 91 is located above the outer steel pipe 92 and the inner steel pipe 93 in a state where the concrete 94 is filled in the inner space A of the inner steel pipe 93. The upper structure 95 is constructed. At this time, in the conventional double steel pipe 91, the overall rigidity of the outer steel pipe 92 and the inner steel pipe 93 is remarkably increased as compared with the surrounding ground 7, and seismic force or the like acts on the conventional double steel pipe 91. In this case, the cross-sectional force F9 acting due to seismic force or the like is concentrated on the double steel pipe 91, and a larger stress P9 is generated on the double steel pipe 91 than on the surrounding ground 7.

  Since the conventional double steel pipe 91 needs to resist the large stress P9 generated in the double steel pipe 91, the plate thickness of the outer steel pipe 92 and the inner steel pipe 93 is increased, and the outer steel pipe 92 and It is necessary to increase the strength of the material of the inner steel pipe 93. On the other hand, in the conventional double steel pipe 91, since the concrete 94 filled in the inner space A of the inner steel pipe 93 cannot bear the stress P9 in the tensile direction, the increase in the stress P9 in the tensile direction is increased by the outer steel pipe. 92 and the inner steel pipe 93 are the burdens.

  In the conventional double steel pipe 91, the concrete space 94 is filled in the inner space A of the inner steel pipe 93, the rigidity is remarkably increased and a large stress P9 is generated, and the plate thickness is increased to resist the stress P9. By increasing the rigidity, the rigidity is further increased and the stress P9 is increased. Of the stress P9, the stress P9 in the tensile direction is borne only by the outer steel pipe 92 and the inner steel pipe 93. A vicious cycle occurs, such as increasing the plate thickness of the inner steel pipe 93.

  In the double steel pipe 1 to which the present invention is applied, as shown in FIG. 19A, the overall rigidity of the outer steel pipe 2 and the inner steel pipe 3 is the same in any of the first to fourth embodiments. It is possible to suppress a significant increase compared to the ground 7, to suppress the cross-sectional force generated by the seismic force, etc., to disperse the acting cross-sectional force F <b> 1 and to outperform the surrounding ground 7. The stress P1 generated in the steel pipe 2 and the inner steel pipe 3 can be reduced.

  As a result, the double steel pipe 1 to which the present invention is applied can avoid the occurrence of a vicious circle like the conventional double steel pipe 91 and increase the plate thickness of the outer steel pipe 2 and the inner steel pipe 3 more than necessary. Without increasing the strength of the material of the outer steel pipe 2 and the inner steel pipe 3 more than necessary, an increase in the manufacturing cost of the double steel pipe 1 to which the present invention is applied can be suppressed, and sufficient supporting force can be provided. It becomes possible to construct | assemble the upper structure 5 which has, suppressing the increase in construction cost.

  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 construed as limiting.

1: Double steel pipe 11: Temporarily curable material 12: Protrusion 13: Non-stress transmitting material 2: Outer steel pipe 2a: Outer surface (outer steel pipe)
2b: Inner surface (outer steel pipe)
2c: Lower end (outer steel pipe)
2d: Upper end (outer steel pipe)
21: excavation bit 22: taper member 22a: base end (taper member)
22b: tip portion (taper member)
23: Giber 24: Horizontal rib plate 25: Inclined rib plate 29: Short steel pipe 3: Inner steel pipe 3a: Outer surface (inner steel pipe)
3b: Inner surface (inner steel pipe)
3c: Lower end (inner steel pipe)
3d: Upper end (inner steel pipe)
31: Spacing member 31a: Base end (spacing member)
31b: tip portion (interval holding member)
31c: Perforated part 5: Superstructure 51: Cross-section connecting beam 52: Sheath pipe 53: Seawall 54: Footing 55: Joint 7: Ground 7a: Support ground layer A: Internal space G: Cavity X: Pipe Axial direction Y: Pipe axis orthogonal direction

Claims (26)

A seawall built on the coast to prevent inundation damage inland,
A double steel pipe provided as a foundation pile on the ground on the sea side and inland side, a cross-sectional connecting beam constructed on the foundation pile on the sea side and inland side, and a wall body,
The double steel pipe has an outer steel pipe provided on the ground simultaneously with excavating the ground, and an inner steel pipe provided on the inner side of the outer steel pipe, and an inner space of the inner steel pipe is hollow, and the inner steel pipe and the A tide embankment characterized in that it is filled with a time-hardening material between the outer steel pipe. The tide embankment according to claim 1, wherein the cross-section connecting beam has a sheath pipe through which the foundation pile is inserted, and is disposed from the sea side ground to the inland side ground. A double steel pipe used as a foundation pile for superstructure,
An outer steel pipe provided on the ground simultaneously with excavating the ground, and an inner steel pipe provided on the inner side of the outer steel pipe,
An upper structure is constructed above the outer steel pipe and the inner steel pipe in a state where the inner space of the inner steel pipe is hollow and the time-hardening material is filled between the inner steel pipe and the outer steel pipe. A double steel pipe characterized by that. One or both of the outer steel pipe and the inner steel pipe are either one or both of the inner surface of the outer steel pipe and the outer surface of the inner steel pipe, and either the upper end or the lower end of the outer steel pipe and the inner steel pipe. The double steel pipe according to claim 3, wherein a gibber is provided in one or both predetermined ranges. The gibber uses a protruding steel pipe for either one or both of the outer steel pipe and the inner steel pipe, or a bar-shaped steel such as a rebar on one or both of the inner surface of the outer steel pipe and the outer surface of the inner steel pipe. The double steel pipe according to claim 4, wherein the steel member is provided by welding. The rib plate which is provided substantially horizontally or incliningly is provided in either one or both of the upper end part and the lower end part of the outer steel pipe and the inner steel pipe. Double steel pipe as described. The double steel pipe according to any one of claims 3 to 6, wherein the height of the top end of the outer steel pipe is substantially the same as the height of the top end of the inner steel pipe. The height of the top end of the outer steel pipe is substantially the same as the height of the top end of the inner steel pipe,
The double steel pipe according to claim 4 or 5, wherein the gibber is provided at least on one or both of an upper end part and a lower end part of the outer steel pipe and the inner steel pipe. The double steel pipe according to any one of claims 3 to 6, wherein a height of a top end of the outer steel pipe is lower than a height of a top end of the inner steel pipe. The height of the top end of the outer steel pipe is lower than the height of the top end of the inner steel pipe,
The said dowel is provided in any one or both of the inner surface of the upper end part of the said outer steel pipe, and the outer surface adjacent to the upper end part of the said outer steel pipe in the said inner steel pipe. Double steel pipe. The height of the top end of the outer steel pipe is lower than the height of the top end of the inner steel pipe,
7. The double steel pipe according to claim 6, wherein the rib plate is provided to extend from an outer surface of the inner steel pipe to an inner surface or an outer surface of the outer steel pipe. The double steel pipe according to any one of claims 3 to 6, wherein a height of a top end of the outer steel pipe is higher than a height of a top end of the inner steel pipe. The height of the top end of the outer steel pipe is higher than the height of the top end of the inner steel pipe,
The said dowel is provided in any one or both of the outer surface of the upper end part of the said inner steel pipe, and the inner surface adjacent to the upper end part of the said inner steel pipe in the said outer steel pipe. Double steel pipe. The height of the top end of the outer steel pipe is higher than the height of the top end of the inner steel pipe,
The double steel pipe according to claim 6, wherein the rib plate is provided so as to extend from an inner surface of the outer steel pipe to an inner surface or an outer surface of the inner steel pipe. The double pipe according to any one of claims 3 to 14, wherein the outer steel pipe is provided with a excavation bit at a lower end portion excavating the ground. The said inner steel pipe is provided with the space | interval holding member which ensures a predetermined space | interval with the inner surface of the said outer steel pipe by attaching a perforated steel plate to an outer surface. Double steel pipe. The outer steel pipe is provided on the ground at the same time as excavating the ground, with the inner steel pipe provided on the inner side and a tapered member provided from the lower end of the inner steel pipe toward the inner surface of the outer steel pipe. The double steel pipe according to any one of claims 3 to 16, wherein the double steel pipe is provided. The non-stress transmitting material is accommodated in the hollow internal space of the inner steel pipe as a member that suppresses an increase in rigidity of the outer steel pipe and the inner steel pipe. The double steel pipe according to item 1. The hollow internal space of the inner steel pipe is filled with a time-hardening material only at the lower end portion of the inner steel pipe that is in the vicinity of the supporting ground layer. Double steel pipe according to item. The inner steel pipe is a protruding steel pipe that protrudes from the inner surface of the lower end, or a barbell steel member such as a reinforcing bar is welded to the inner surface of the lower end. Item 20. The double steel pipe according to Item 19. The hollow internal space of the inner steel pipe is filled with a time-curable material only in a range in which circumferential stress is generated in one or both of the inner steel pipe and the outer steel pipe. The double steel pipe according to any one of claims 3 to 18. A construction method of an upper structure in which a double steel pipe is used as a foundation pile,
At the same time excavating the ground with an outer steel pipe provided with a drilling bit at the lower end, the outer steel pipe installation step of providing the outer steel pipe on the ground,
An inner steel pipe is provided on the inner side of the outer steel pipe, and an inner steel pipe installation step of filling a time-hardening material between the inner steel pipe and the outer steel pipe;
And a structure construction step of constructing an upper structure above the outer steel pipe and the inner steel pipe in a state where the inner space of the inner steel pipe is hollow. A construction method of an upper structure in which a double steel pipe is used as a foundation pile,
At the same time as excavating the ground with an outer steel pipe provided with a drilling bit at the lower end and an inner steel pipe inside, the outer steel pipe and the inner steel pipe are provided on the ground, and between the inner steel pipe and the outer steel pipe. A double steel pipe installation process for filling a time-curable material;
And a structure construction step of constructing an upper structure above the outer steel pipe and the inner steel pipe in a state where the inner space of the inner steel pipe is hollow. 23. In the structure construction step, the time-hardening material is filled into a hollow internal space of the inner steel pipe only at a lower end portion of the inner steel pipe that is in the vicinity of a supporting ground layer. The construction method of the superstructure of 23. In the structure construction step, the time-hardening material is filled only in a range in which a circumferential stress is generated in one or both of the inner steel pipe and the outer steel pipe in the hollow inner space of the inner steel pipe. The method for constructing an upper structure according to claim 22 or 23, wherein: In the structure construction step, in the hollow internal space of the inner steel pipe, in order to suppress an increase in rigidity of the outer steel pipe and the inner steel pipe, the outer steel pipe and The method for constructing an upper structure according to any one of claims 22 to 25, wherein the upper structure is constructed above the inner steel pipe.