JP2010168734A - Steel pipe for pile and the pile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steel pipe for a pile provided with a reinforcing rib capable of reinforcing the steel pipe itself. <P>SOLUTION: In this steel pipe 1, the reinforcing rib 2 is formed on its inner peripheral face 1a. The reinforcing rib 2 is provided with a reinforcing rigid face part 21 abutted on the inner peripheral face like a belt and a protruding face part 22 extended toward shaft axis from the reinforcing rigid face part. Here, the reinforcing rigid face part and the protruding face part cross mutually and substantially orthogonally. Preferably, both side edges of the reinforcing rigid face part 21 are joined with the inner peripheral face 1a through welded parts 23, 23. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a steel pipe for pile in which reinforcing ribs are formed on an inner peripheral surface, and a pile constructed using the steel pipe.

  Conventionally, steel pipes for piles are known in which ribs are provided on the inner peripheral surface of a steel pipe by reinforcing bars or weld beads, and the adhesive force (friction resistance) with concrete filling the inner space is increased (see Patent Documents 1 to 3, etc.). ).

  For example, Patent Document 1 discloses a pile in which the upper part of the pile is a steel pipe concrete pile and the lower part is a cast-in-place concrete pile. A footing and a cast-in-place are provided on the inner peripheral surfaces of the upper end and the lower end of the steel pipe. An annular rib is provided to increase the bonding strength with the concrete pile.

  Further, in Patent Document 2, a plurality of protrusions (ribs) are axially spaced on the inner peripheral surface of the lower end of the steel pipe in order to reinforce the connection between the expanded bottom portion of the tip root pile and the upper steel pipe. Steps and provided piles are disclosed.

  Furthermore, Patent Document 3 discloses a method of manufacturing a steel pipe for providing a convex protrusion (rib) on the inner peripheral surface of the steel pipe.

JP 2006-138095 A JP-A-6-158654 JP 59-49118 A

  However, the ribs disclosed in Patent Documents 1 to 3 are linear ribs and can increase the adhesion between the steel pipe and the concrete, but do not reinforce the steel pipe itself.

  That is, the height of the linear rib projecting in the axial direction of the steel pipe becomes a shear resistance and can increase the adhesion to the concrete, but reinforces the steel pipe itself so as to improve the bending strength of the steel pipe. There is no effect.

  In addition, when the rib is provided by a cylindrical rod such as a reinforcing bar, the contact surface with the inner peripheral surface of the steel pipe is linear and very small, so it must be firmly fixed unless the welding amount is increased. Is difficult.

  Then, this invention aims at providing the pile constructed | assembled using the steel pipe for piles provided with the reinforcement rib which can reinforce steel pipe itself, and it.

  In order to achieve the above object, a steel pipe for piles according to the present invention is a steel pipe for piles in which reinforcing ribs are formed on the inner peripheral surface, and the reinforcing ribs are stiffened in contact with the inner peripheral surface in a band shape. A surface portion and a projecting surface portion extending from the stiffening surface portion toward the axial center are provided.

  Here, it is preferable that an edge portion of the stiffening surface portion is joined to the inner peripheral surface by welding. Further, the stiffening surface portion and the protruding surface portion may be substantially orthogonal to each other.

  Furthermore, it can also be set as the structure provided with the connection board interposed between at least one of the said stiffening surface part or the said internal peripheral surface, and the said protrusion surface part. A plurality of the connecting plates may be provided at intervals in the circumferential direction. Furthermore, it is preferable that the interval in the circumferential direction of the connecting plate is 1 to 5 times the width of the stiffening surface portion.

  Moreover, the structure which the spacer which protrudes toward an axial center may be attached to the edge part by the side of the axial center of the said protrusion surface part.

  Further, the reinforcing rib can be provided in an annular shape. In addition, a cutout portion may be formed in the protruding surface portion. A plurality of reinforcing ribs may be provided at intervals in the circumferential direction.

  Moreover, the pile of this invention is filled with the cement-type solidification material in the inner space of said steel pipe for piles, It is characterized by the above-mentioned. Moreover, it can also be set as the structure provided with the steel pipe concrete pile part by which concrete was filled in the inner space of said steel pipe for piles, and the cast-in-place concrete pile part provided in the downward direction.

  The steel pipe for a pile of the present invention configured as described above is a reinforcement provided with a stiffening surface portion that abuts on the inner peripheral surface in a band shape and a protruding surface portion that extends from the stiffening surface portion toward the axis. Ribs are attached.

  Since this stiffening surface part is contact | abutted by the strip | belt shape to the internal peripheral surface of a steel pipe, the bending strength of steel pipe itself can be improved. Furthermore, since the projecting surface portion extends toward the axis, the adhesive force can be increased when the interior space is filled with a cement-based solidifying material such as concrete.

  Moreover, the reinforcing rib can be firmly fixed to the steel pipe by joining the edge portion of the stiffening surface portion to the inner peripheral surface by welding.

  Furthermore, if the stiffening surface portion and the protruding surface portion are substantially orthogonal, the reinforcing rib can be easily formed using a general-purpose angle material or the like.

  Also, by interposing a connecting plate between the stiffening surface part or inner peripheral surface and the projecting surface part, the bending strength of the projecting surface part is increased, and as a result, the stress generated around the reinforcing rib is reduced and the steel pipe is reinforced. The same effect can be obtained. In particular, the steel pipe can be reinforced directly by fixing one end of the connecting plate to the inner peripheral surface.

  Furthermore, the rigidity of the reinforcing rib can be easily adjusted by providing a plurality of connecting plates at intervals in the circumferential direction. In particular, when connecting plates are provided at intervals of 1 to 5 times the width of the stiffening surface, the strength of the concrete filled in the interior and the amount of concrete and steel used can be set rationally. And economical.

  In addition, a spacer is attached to the edge on the axial center side of the projecting surface, and the rebar inserted into the inner space of the steel pipe for pile is brought into contact with the spacer, so that the distance between the rebar and the inner peripheral surface of the steel pipe is constant. Can be held.

  Further, if the reinforcing ribs are attached in an annular shape, they can be evenly reinforced around the entire circumference of the steel pipe. Furthermore, if a notch part is provided in the protruding surface part, the reinforcing bar can be passed through the notch part in the axial direction. Further, when a reinforcing bar rod or the like is inserted into the steel pipe, even if a reinforcing bar rod spacer or the like protrudes in the horizontal direction, it can be passed by aligning the position of the protrusion with the notch.

  In addition, by providing reinforcing ribs at intervals in the circumferential direction, the same effects as when the above-described notch portions are provided can be obtained, and the use of materials is compared to when reinforcing ribs are provided all around the circumference. The amount can be reduced.

  Furthermore, the pile in which the cement-type solidification material is filled in the inside of such a steel pipe for piles has a large adhesive force between the steel pipe and the cement-type solidification material, and can integrally resist the external force.

  Moreover, if it is a pile of the composite structure of a steel pipe concrete pile part and a cast-in-place concrete pile part, the freedom degree of a design will be large and an economical pile can be constructed | assembled.

It is a partial expansion perspective view explaining the composition of the steel pipe of the best embodiment of the present invention. It is sectional drawing explaining the structure of the pile of the best embodiment of this invention. It is a perspective view explaining the structure of the junction part vicinity of a steel pipe concrete pile part and a cast-in-place concrete pile part. It is a figure explaining the effect | action of a reinforcement rib, Comprising: (a) is a figure explaining the effect | action of a stiffening surface part, (b) is a figure explaining the effect | action of a connection plate. It is a figure explaining the structure of the reinforcement rib of Example 1, Comprising: (a) is a perspective view explaining the structure of a triangular connection board, (b) is a perspective view explaining the structure of a pentagonal connection board. is there. It is a figure explaining the effect | action of the reinforcement rib of Example 2, Comprising: (a) is a figure explaining the effect | action of the connection board provided in the upper side of the protrusion surface part, (b) of the connection board provided in the both sides of the protrusion surface part. It is a figure explaining an effect | action. It is sectional drawing explaining the joint structure of the penetration reinforcement inserted in the steel pipe of Example 3, and a reinforcement rod. It is a perspective view explaining the structure which attaches the penetration reinforcing bar of Example 3. FIG. It is a figure explaining the structure of the reinforcement rib of Example 4, Comprising: (a) is a perspective view explaining the structure which provided the notch part, (b) is the structure which attached the reinforcement rib at intervals in the circumferential direction. It is a perspective view explaining.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a partially enlarged perspective view in which a part of the steel pipe 1 is cut out in order to explain the configuration of the steel pipe 1 as the pile steel pipe of the present embodiment. 2 and 3 are diagrams illustrating the configuration of the pile 6 constructed using the steel pipe 1.

  As shown in FIGS. 2 and 3, annular reinforcing ribs 2 and 2 are attached to the steel pipe 1 on two inner peripheral surfaces 1 a near the upper end and the lower end.

  As shown in FIG. 1, the reinforcing rib 2 includes a stiffening surface portion 21 that is in contact with the inner peripheral surface in a band shape, and a protruding surface portion 22 that extends from the stiffening surface portion 21 toward the axis of the steel pipe 1. It has.

  The stiffening surface portion 21 and the protruding surface portion 22 have substantially the same width L, and are orthogonal to each other with the side edges that are the edge portions in the width direction abutting each other. For this reason, the reinforcing rib 2 can be made of an angle material (an angle steel material) having a substantially L shape in cross section.

  A plurality of connecting plates 3 and 3 are attached to the reinforcing rib 2 with a distance D in the circumferential direction. The connecting plate 3 shown in FIG. 1 is a right-angled triangular steel plate, and is attached to the inner angle side of the stiffening surface portion 21 and the protruding surface portion 22. Further, the connecting plate 3 and the stiffening surface portion 21 and the protruding surface portion 22 are substantially orthogonal.

  Further, the reinforcing rib 2 is fixed by performing fillet welding between the upper edge and the lower edge, which are the edges of the stiffening surface portion 21, and the inner peripheral surface 1a of the steel pipe 1, thereby providing the welded portions 23, 23. Is done.

  Then, an example of the pile 6 constructed | assembled using such a steel pipe 1 is demonstrated, referring FIG.

  This pile 6 is a support body that supports an upper load acting via the footing 4, and includes an upper steel pipe concrete pile portion 10 and a lower cast-in-place concrete pile portion 5.

  The steel pipe concrete pile portion 10 includes a steel pipe 1 in which reinforcing ribs 2 and 2 are attached in the vicinity of the upper end portion joined to the footing 4 and the lower end portion joined to the cast-in-place concrete pile portion 5, respectively, It is mainly comprised by the concrete 11 as a cement-type solidification material with which it fills (refer FIG.2, 3).

  Here, for the steel pipe 1, for example, a steel pipe material having a diameter of about 700 mm to 2500 mm can be used. Further, the reinforcing rib 2 can be an equilateral angle material having a width L of the stiffening surface portion 21 and the protruding surface portion 22 of 25 mm to 150 mm, or an unequal angle angle material having a width of two sides different from 90 mm × 75 mm to 150 mm × 100 mm. .

  A plurality of fixing bars 43... Are attached to the outer peripheral surface at the upper end of the steel pipe 1 by welding or the like. Further, between the vicinity of the upper end of the steel pipe 1 and the lower part of the footing 4, a plurality of reinforcing bars 41,. The lower ends of the reinforcing bars 41,... Extend downward from the upper reinforcing rib 2.

  On the other hand, the cast-in-place concrete pile portion 5 includes a reinforcing bar 51 extending in the axial direction (vertical direction), concrete 52 filled in the periphery thereof, and an expanded bottom portion 53 provided in the lower portion. Further, the upper end of the reinforcing bar 51 extends upward from the lower reinforcing rib 2.

  Next, the effect | action of the steel pipe 1 and the pile 6 of this Embodiment is demonstrated.

  The steel pipe 1 of the present embodiment configured as described above includes a stiffening surface portion 21 that is in contact with the inner peripheral surface 1a in a band shape, and a protruding surface portion 22 that extends from the stiffening surface portion 21 toward the axis. The reinforcing rib 2 provided with is attached.

  As shown in FIG. 4 (a), the stiffening surface portion 21 is in contact with the inner peripheral surface 1a of the steel pipe 1 in a band shape, so that it becomes a resistance material of the bending moment MA acting on the steel pipe 1 and has a bending strength. Can be increased.

  Further, since the projecting surface portion 22 extends toward the axis, when the concrete 11 is filled in the inner space, the projecting surface portion 22 becomes a shear resistance and the adhesion force can be increased.

  Moreover, the reinforcing rib 2 can be firmly fixed to the steel pipe 1 by joining the upper edge and the lower edge of the stiffening surface portion 21 to the inner peripheral surface 1a by the welded portions 23, 23. That is, since the contact area between the stiffening surface portion 21 and the inner peripheral surface 1a is wide, the attachment work of the reinforcing rib 2 can be performed in a stable state, and the quality can be improved.

  Furthermore, if the stiffening surface portion 21 and the protruding surface portion 22 are substantially orthogonal, the reinforcing rib 2 can be easily formed using a general-purpose angle material or the like. That is, if a member for the reinforcing rib 2 is specially ordered, the cost increases, but if it is an angle material, it can be easily obtained and the cost can be reduced.

  Further, by interposing the connecting plate 3 between the stiffening surface portion 21 and the projecting surface portion 22, as shown in FIG. 4B, a bending moment MB acts through the concrete 11 filled therein. In addition, the connecting plate 3 serves as a support material, and the protruding surface portion 22 is not easily bent. As described above, when the bending strength of the projecting surface portion 22 is increased, as a result, the stress generated around the attachment location of the reinforcing rib 2 is reduced, and the same effect as that of reinforcing the steel pipe 1 itself can be obtained.

  Furthermore, the rigidity of the reinforcing rib 2 can be easily adjusted by providing a plurality of connecting plates 3 at intervals D in the circumferential direction.

  For example, when the reinforcing rib 2 is formed of an equilateral angle material (thickness t = 3 mm to 12 mm) with one side L (25 mm to 100 mm), if the interval D of the connecting plate 3 is four times L, the inner space of the steel pipe 1 Various angle materials can be applied in accordance with the strength of the concrete 11 filled in, and a rational and economical design can be performed.

  If the distance D between the connecting plates 3 is about 1 to 5 times L, the strength of the concrete 11 to be filled and the size of the angle material used for the reinforcing rib 2 can be adjusted to make a reasonable steel pipe concrete pile. Part 10 can be constructed.

  Further, the reinforcing rib 2 is formed so that the stiffening surface portion 21 hangs downward from the protruding surface portion 22, and the connecting plates 3... Are also provided below the protruding surface portion 22. For this reason, excavated earth and sand are hard to collect between the connecting plates 3 and 3, and the concrete 11 can be filled around the reinforcing rib 2 with almost no earth and sand interposed.

  Further, if the reinforcing rib 2 is attached in an annular shape, it can be evenly reinforced on the entire circumference of the steel pipe 1.

  Further, in the steel pipe concrete pile portion 10 in which the concrete 11 is filled in the inner space of the steel pipe 1, the adhesive force between the steel pipe 1 and the concrete 11 is increased due to the shear resistance of the projecting surface portion 22, and it is integrated with the external force. Can be resisted.

  Moreover, if it is the pile 6 of the composite structure of the steel pipe concrete pile part 10 and the cast-in-place concrete pile part 5, the freedom degree of a design will be large and the pile 6 of the desired performance can be constructed economically.

  Hereinafter, Example 1 as a form different from the above-described embodiment will be described with reference to FIG. The description of the same or equivalent parts as those described in the above embodiment will be given the same reference numerals.

  In Example 1, reinforcing ribs 2A and 2B different from those described in the above embodiment will be described.

  In the reinforcing rib 2 </ b> A shown in FIG. 5A, the stiffening surface portion 21 and the protruding surface portion 22 are substantially orthogonal to each other like the reinforcing rib 2 described above. In addition, the direction shown in this figure does not prescribe | regulate the attachment direction of reinforcement rib 2A, 2B.

  The connecting plate 31 attached to the reinforcing rib 2A is a steel plate having a substantially right-angled triangle shape, but its side is longer than the width of the stiffening surface portion 21, and the upper side of the stiffening surface portion 21 as viewed in FIG. The protrusion part 31a which protrudes in is provided.

  On the other hand, also in the reinforcing rib 2B shown in FIG. 5B, the stiffening surface portion 21 and the protruding surface portion 22 are substantially orthogonal to each other. The connecting plate 32 attached to the reinforcing rib 2B is a pentagonal steel plate, but its side is longer than the width of the stiffening surface portion 21, and protrudes above the stiffening surface portion 21 as seen in FIG. Protruding portion 32a is provided.

  Thus, by increasing the area of the connecting plates 31 and 32, the rigidity of the connecting plates 31 and 32 and the reinforcing ribs 2A and 2B can be increased. And the bending strength of the steel pipe 1 can also be increased by increasing the rigidity of the reinforcing ribs 2A and 2B.

  Moreover, the rigidity of steel pipe 1 itself can also be improved by welding protrusion part 31a, 32a to the internal peripheral surface 1a of the steel pipe 1. FIG.

  Other configurations and functions and effects are substantially the same as those in the above-described embodiment, and thus description thereof is omitted.

  Hereinafter, Example 2 as a form different from the above-described embodiment will be described with reference to FIG. The description of the same or equivalent parts as those described in the embodiment and Example 1 will be given with the same reference numerals.

  In the second embodiment, a case where the connecting plate 33 is interposed between the inner peripheral surface 1a of the steel pipe 1 and the protruding surface portion 22 will be described.

  In the reinforcing rib 2 </ b> C shown in FIG. 6A, a right-angled triangular steel plate is attached as a connecting plate 33 on the upper side of the protruding surface portion 22. And the side part 33a of this connection plate 33 is contact | abutted to the internal peripheral surface 1a of the steel pipe 1, and is joined to the steel pipe 1 by the welding part 23. FIG.

  In this way, by providing the connecting plate 33 extending in the direction opposite to the stiffening surface portion 21 with the protruding surface portion 22 interposed therebetween, the steel pipe 1 itself is reinforced in a long range in the axial direction, and the resistance to the bending moment MA is increased. Can be increased.

  Further, the connecting plate 33 attached to the upper side functions as a bending resistance against the bending moment MB acting on the protruding surface portion 22.

  On the other hand, the reinforcing rib 2D shown in FIG. 6B is provided with a connecting plate 33 on the upper side of the protruding surface portion 22 in the same manner as the reinforcing rib 2C described above, and the lower connecting plate 34 is a stiffening surface portion 21. A protrusion 34a protruding further downward is provided.

  Such a reinforcing rib 2D can reinforce the steel pipe 1 itself in a longer range than the above-described reinforcing rib 2C. Further, since the connecting plates 33 and 34 are attached to both sides of the protruding surface portion 22, the bending resistance of the protruding surface portion 22 is remarkably improved, and the rigidity of the reinforcing rib 2D is extremely increased.

  Other configurations and functions and effects are substantially the same as those of the above-described embodiment or other examples, and thus description thereof is omitted.

  Hereinafter, Example 3 as a form different from the above-described embodiment will be described with reference to FIGS. The description of the same or equivalent parts as those described in the embodiment and other examples will be given with the same reference numerals.

  In the inner space of the steel pipe 1 described in the third embodiment, a plurality of penetrating rebars 45 that penetrate the steel pipe 1 in the axial direction are arranged.

  The penetrating rebars 45 are attached in contact with the edge of the projecting surface 22 of the reinforcing rib 2 attached to the inner peripheral surface 1a of the steel pipe 1 or the spacer 44 attached to the edge.

  For example, as shown in FIG. 8A, a spacer 44 whose side surface is formed in an arc shape is attached to the edge of the projecting surface portion 22, the peripheral surface of the penetrating rebar 45 is brought into contact with the spacer 44, and the binding wire 46 or the like. Secure with. Further, as shown in FIG. 8 (b), the peripheral surface of the penetrating rebar 45 can be brought into direct contact with the edge of the projecting surface portion 22 and fixed with a binding wire 46 or the like.

  The penetrating rebars 45 are configured such that the upper end and the lower end protrude from the opening of the steel pipe 1. For example, a fixing bar 43 is attached to the outer peripheral surface of the upper end of the steel pipe 1, and the upper end of the penetrating rebar 45 protrudes to a position substantially the same as the upper end position of the fixing bar 43. On the other hand, the lower end of the penetration reinforcing bar 45 protruding from the lower end of the steel pipe 1 is protruded to the position where the upper end of the reinforcing bar rod 51 connected thereto can be overlapped.

  In addition, although the rebar longer than the full length of the steel pipe 1 can also be used for this penetration rebar 45, the structure which adds a rebar through joint parts, such as a coupler, and shape | molds in desired length may be sufficient. .

  In the steel pipe 1 according to the third embodiment configured as described above, penetrating rebars 45 are arranged. And since the steel pipe concrete pile part 10 constructed | assembled using the steel pipe 1 by which the penetration reinforcement 45, ... was arranged is reinforced by the penetration reinforcement 45, ..., the thickness of the steel pipe 1 is made thin. Even so, the desired rigidity can be ensured and it is economical.

  Further, the peripheral surface of the penetrating rebars 45,... Is brought into contact with the edge portion on the axial center side of the projecting surface portion 22 of the reinforcing rib 2 or the spacers 44,. The space | interval of the reinforcing bar 45 and the internal peripheral surface 1a of the steel pipe 1 can be kept constant. For example, when the minimum interval between the penetrating rebar 45 and the inner peripheral surface 1a of the steel pipe 1 is defined by design, the minimum interval can be ensured reliably. Moreover, although the bending strength of the steel pipe concrete pile part 10 changes with the position where the penetration rebar 45 is arrange | positioned, adjusting the protrusion amount of the spacer 44 can arrange the penetration rebar 45 in the position as designed. it can.

  In addition, by protruding the penetration reinforcing bar 45 above the steel pipe 1, the number of fixing bars 43 can be reduced, which is economical. That is, since the fixing bar 43 is joined to the outer peripheral surface of the steel pipe 1 by welding, it takes time to mount the fixing bar 43, but by attaching the fixing bar 43 by projecting the penetrating rebar 45 upward and using it for joining with the footing 4. The number can be reduced, and the manufacturing cost can be reduced.

  Furthermore, by making the penetration reinforcing bar 45 project below the steel pipe 1, it is possible to easily perform the joint with the reinforcing bar 51.

  Other configurations and functions and effects are substantially the same as those of the above-described embodiment or other examples, and thus description thereof is omitted.

  Hereinafter, Example 4 as a form different from the above-described embodiment will be described with reference to FIG. The description of the same or equivalent parts as those described in the embodiment and other examples will be given with the same reference numerals.

  In the fourth embodiment, a case where the reinforcing bar 41 is arranged in the steel pipe 1 or the reinforcing bar 51 is passed will be described.

  For example, as shown in FIG. 9A, when the reinforcing bar 41 is arranged in the inner space of the steel pipe 1, the protruding surface portion 22 protrudes toward the axial center. ) Will be arranged. On the other hand, depending on the design, the reinforcing bar 41 may need to be disposed closer to the inner peripheral surface 1a than the protruding surface portion 22.

  In such a case, a reinforcing rib 2E is formed on the steel pipe 1 by cutting out a part of the projecting surface portion 22 at a position where the reinforcing bar 41 and the coupler 42 serving as a joint portion are disposed.

  With such a reinforcing rib 2E, the reinforcing bar 41 can be arranged near the outer periphery of the pile by disposing the reinforcing bar 41 and the coupler 42 in the notch 22a and fixing them with the binding wire 46.

  On the other hand, FIG. 9B shows a form in which a plurality of arc-shaped reinforcing ribs 2F are attached at intervals in the circumferential direction. Also in this case, a gap is opened between the reinforcing ribs 2F and 2F, and thus the reinforcing bar 41 and the coupler 42 can be arranged in the gap.

  Further, when the reinforcing bar 51 is disposed below the inner space of the steel pipe 1, the reinforcing rib 2F, even if the spacer 54 or the like protrudes in the lateral direction as shown in FIG. The reinforcing bar 51 can be passed by passing through the gap between 2F.

  Further, by providing the reinforcing ribs 2F and 2F at intervals in the circumferential direction, the amount of material used can be reduced as compared with the annular reinforcing ribs 2, which is economical.

  Further, when the reinforcing ribs 2F are attached at intervals in the circumferential direction, the first connecting plate is located at a position substantially the same length as the width L of the stiffening surface portion 21 from the side end surface of the reinforcing rib 2F in the circumferential direction. 3 and then the second connecting plate 3 is attached at a distance D approximately twice that of L, the bending moment between the end of the reinforcing rib 2F in the circumferential direction and the connecting plates 3 and 3 becomes substantially the same. Can be a reasonable stress distribution.

  Other configurations and functions and effects are substantially the same as those of the above-described embodiment or other examples, and thus description thereof is omitted.

  The embodiments and examples of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the embodiments and examples, and the gist of the present invention is not deviated. Design changes are included in the present invention.

  For example, in the above-described embodiment or example, the case where the one-stage reinforcing rib 2 is provided in the vicinity of the upper end and the lower end of the steel pipe 1 has been described. A plurality of stages of reinforcing ribs 2 can be provided. Moreover, you may provide many reinforcement ribs 2 ... in the axial direction over the full length of the steel pipe 1 at intervals.

  Moreover, in the said embodiment or Example, although the circular surface formed by the cyclic | annular reinforcement rib 2 was attached so that it might orthogonally cross with an axial center, it is not limited to this, It is diagonal with respect to an axial center Reinforcing ribs that are made into a spiral or spiral may be attached.

  Furthermore, in the said embodiment or Example, although the side edge of the stiffening surface part 21 and the side edge of the protrusion surface part 22 demonstrated substantially L-shaped reinforcement rib 2 in cross section, it limited to this Instead, it is a reinforcing rib in which the projecting surface portion 22 obliquely intersects with the stiffening surface portion 21, or a substantially T-shaped cross-sectional view or a schematic cross-sectional view in which the projecting surface portion 21 extends from the surface of the stiffening surface portion 21. It may be an r-shaped reinforcing rib.

  Moreover, in the said embodiment, although the reinforcement rib 2 was attached so that the stiffening surface part 21 might hang down from the protrusion surface part 22, it is not limited to this, For example, it is upward from the protrusion surface part 22 of the direction opposite to this The reinforcing rib 2 can be attached so that the stiffening surface portion 21 extends toward the surface.

  Furthermore, although the said embodiment demonstrated the case where concrete was filled in the inside of the steel pipe 1, it is not limited to this, The prefabricated pile which fills the concrete 11 in the factory in the inside of a pipe is manufactured. Even in this case, the steel pipe 1 of the present invention can be used.

  Moreover, although the said embodiment demonstrated the case where the concrete 11 was filled as a cement-type solidification material, it is not limited to this, Mortar, soil cement, fluidized soil, etc. are used as a cement-type solidification material. You can also

  Further, in the above embodiment, a method for fixing the reinforcing bar 41 to the steel pipe 1 is not described in detail. However, as described in the third and fourth embodiments, the reinforcing ribs 2 and 2E and the spacers using the binding wire 46 and the like. The method of attaching to 44 can be applied.

1 Steel pipe (pile steel pipe)
1a Inner peripheral surface 10 Steel pipe concrete pile part 11 Concrete (cement system solidification material)
2 Reinforcing ribs 2A, 2B, 2C, 2D, 2E, 2F Reinforcing rib 21 Stiffening surface portion 22 Protruding surface portion 22a Notch portion 23 Welded portion 3 Connecting plates 31, 32, 33, 34 Connecting plate 44 Spacer 5 Cast-in-place concrete pile portion 6 Pile D Interval L Width

Claims (12)

A steel pipe for piles in which reinforcing ribs are formed on the inner peripheral surface,
The steel pipe for piles, wherein the reinforcing rib includes a stiffening surface portion that abuts on the inner peripheral surface in a band shape, and a protruding surface portion that extends from the stiffening surface portion toward the axis.   The steel pipe for piles according to claim 1, wherein an edge portion of the stiffening surface portion is joined to the inner peripheral surface by welding.   The steel pipe for a pile according to claim 1 or 2, wherein the stiffening surface portion and the protruding surface portion are substantially orthogonal to each other.   The steel pipe for piles as described in any one of Claim 1 thru | or 3 provided with the connection board interposed between at least one of the said stiffening surface part or the said internal peripheral surface, and the said protrusion surface part.   The pile steel pipe according to claim 4, wherein a plurality of the connecting plates are provided at intervals in the circumferential direction.   The steel pipe for piles according to claim 5, wherein the interval of the connecting plates in the circumferential direction is 1 to 5 times the width of the stiffening surface portion.   The pile steel pipe according to any one of claims 1 to 6, wherein a spacer projecting toward the axial center is attached to an edge of the protruding surface portion on the axial center side.   The pile steel pipe according to any one of claims 1 to 7, wherein the reinforcing rib is provided in an annular shape.   The steel pipe for piles according to claim 8, wherein a notch portion is formed in the protruding surface portion.   The steel pipe for pile according to any one of claims 1 to 7, wherein a plurality of the reinforcing ribs are provided at intervals in the circumferential direction.   The pile characterized by the cement-type solidification material being filled in the inner space of the steel pipe for piles as described in any one of Claims 1 thru | or 10.   The steel pipe concrete pile part by which concrete was filled in the inner space of the steel pipe for piles as described in any one of Claims 1 thru | or 10, and the cast-in-place concrete pile part provided in the downward direction were provided. Pile.

Images