JP5284249B2 - Steel pipe sheet pile joint structure and steel pipe sheet pile foundation - Google Patents

Description

  The present invention relates to a steel pipe sheet pile joint structure and a steel pipe sheet pile foundation, and more particularly, by fitting one female joint and the other male joint in a pair of steel pipe sheet pile main pipes placed next to each other. The present invention relates to a joint structure of steel pipe sheet piles that connect the steel pipe sheet pile main pipes, and a steel pipe sheet pile foundation including a plurality of steel pipe sheet pile main pipes connected by the joint structure.

Conventionally, as a joint structure of steel pipe sheet piles, a circular joint steel pipe having a slit is fixed to each of adjacent steel pipe sheet piles, and steel pipe sheet piles are continuously built in the ground while fitting these joint steel pipes, A joint structure is generally used in which mortar is filled in a joint steel pipe and the steel pipe sheet piles are connected to each other after excavating and cleaning the earth and sand in the joint steel pipe. Such a joint structure is called a P (pipe) -P (pipe) joint (PP joint) because joint steel pipes (P: pipes) are fitted to each other.
Moreover, as a joint structure of a steel pipe sheet pile in addition to the PP joint, a pipe pipe sheet pile is connected by fitting a joint steel pipe having a slit in the axial direction and a T-shaped male joint made of T-shaped steel to each other. A steel pipe sheet pile by fitting a T joint (see Patent Document 1), a female joint made of a pair of L-shaped steels installed in parallel and spaced apart from each other, and a male joint made of one T-shaped steel. In some cases, an LT joint or the like that connects the two is used.
In the fitting joint structure described in Patent Document 1, a T-shaped steel with protrusions, which is a male fitting joint having a plurality of protrusions on the surface, and a female fitting having a plurality of protrusions on the inner surface A jointed steel pipe with a projection, which is a joint, is fitted, and mortar is placed inside the jointed steel pipe with a projection.

The conventional joint structure as described above has the following disadvantages.
First, in the case of a PP joint, since three spaces are formed in the fitting joint portion in which the joints are fitted to each other, soil excavation and cleaning are performed in each space of the narrow joint portion after fitting the joint. It is necessary to carry out each operation such as mortar filling. For this reason, it is difficult to perform reliable cleaning and solid mortar filling of the joint part, and the quality may become unstable. There is a possibility that the shear strength cannot be exhibited reliably.
Also, in the PT joint and the LT joint, as in the case of the PP joint, since the joint fitting space is narrow, the joint portion is reliably cleaned and filled with a solid mortar. This is difficult and the quality may become unstable, so that the shear strength of the joint portion may not be exhibited reliably. Furthermore, in PT joints and LT joints, when a horizontal force acts on a steel pipe sheet pile due to an earthquake, earth pressure, water pressure, etc., the shearing force generated between the steel pipe sheet piles is transmitted to the joint part, and the joints are relatively By shifting, a relative displacement occurs between the mortar and the joint, and the mortar expands. As a result, the joint steel pipe and the female joint made of L-shaped steel are deformed in the opening direction. There is also a disadvantage that the adhesion between the steel and the mortar is reduced, and the shear strength of the joint is further reduced.

As a joint structure that eliminates the disadvantages of the conventional joint structure as described above, improves the workability related to excavation, cleaning, and mortar filling of the joint part, and secures the shear strength of the joint part, An LL joint has been proposed in which a female joint in which an arm portion of an L-shaped steel material is disposed inward and a male joint in which an arm portion of a pair of L-shaped steel materials is disposed outward are fitted to each other ( Patent Document 2).
In the LL joint described in Patent Document 2, a plurality of bar-like steel materials with protrusions are fixed at predetermined intervals to the outer peripheral surface of the main pipe sandwiched between the L-shaped steel materials in the female joint and the male joint. It is possible to surely exhibit the adhesive strength and to exhibit excellent shear strength. Furthermore, since the leg part length of the L-shaped steel material is a joint part that is appropriately set so as to ensure the accuracy of installation, the joint part has an appropriate fitting margin. It can be used as a guide at the time of erection, and the steel pipe sheet pile can be erected with high accuracy. And because it has enough space for soil excavation and cleaning in mating joints and filling work of cement-based room temperature curable materials (fillers) such as mortar, the excavation of earth and sand in mating joints is ensured. In addition, the fitting joint can be reliably cleaned, and the filling material can be filled into the fitting joint in a solid manner. Therefore, in the joint structure described in Patent Document 2, the workability is dramatically improved and the quality is stable, and the sticking to the filler is ensured by the rod-shaped steel material on the outer peripheral surface of the steel pipe sheet pile main pipe. Since the shear strength of the part can be improved, it is possible to reduce the construction cost and the construction period by reducing the number of steel pipes and the steel pipe sheet thickness by improving the stability of the entire foundation. .

JP-A-8-27774 JP 2005-282174 A

However, in the joint structure described in Patent Document 2, it is a structure that expects adhesion between a plurality of rod-shaped steel materials with protrusions and a filler on the outer peripheral surface of the main pipe, and is composed of a filler surrounded by the main pipe and the L-shaped steel material. tensile force acts on the filler for large adhesion to the both end portions of the main pipe side of the cross-section occurs over from one main pipe immediately filler after the maximum shear force is exerted on the other main diagonal shear Cracks occur. It is known that when the shear shear crack occurs after the maximum shear force is generated, the shear force decreases rapidly. This is because when the steel sheet pile foundation receives horizontal force due to earthquake or horizontal force due to earth pressure, etc. Relative displacement in the vertical direction occurs between each other, and shear resistance is exerted at the joint, but when the relative deformation of the joint increases, the shear force decreases rapidly, so the energy that can be absorbed is small It is.

  An object of the present invention is to provide a steel pipe sheet pile joint structure capable of ensuring good workability and stable quality, reducing the construction cost and shortening the construction period, and exhibiting the stable shear strength of the joint part. And to provide steel pipe sheet pile foundation.

  The steel pipe sheet pile joint structure of the present invention connects the steel pipe sheet pile main pipes by fitting one female joint and the other male joint out of a pair of steel pipe sheet pile main pipes that are placed next to each other. A steel pipe sheet pile joint structure, wherein the female joint has a pair of female L-type steel materials having legs fixed to the outer surface of the one steel pipe sheet pile main pipe, and the pair of female L-type steel materials. Arm portions are arranged inwardly approaching each other, and the male joint has a pair of male L-shaped steel materials with legs fixed to the outer surface of the other steel pipe sheet pile main pipe, and the pair of male L-shaped steel materials. The arm portions of the pair of male L-shaped steel members are arranged outwardly from each other, and the opposing surfaces of the pair of male L-shaped steel members are provided with irregularities, and the pair of females on the outer peripheral surface of the one steel pipe sheet pile main pipe The region sandwiched between the legs of the L-shaped steel material has It covers the least part, characterized in that the irregularities plate-shaped member that is formed is provided on the surface.

  According to the present invention described above, the plate-like member provided on the outer peripheral surface of the steel pipe sheet pile main pipe sandwiched between the opposing surfaces of the legs of the pair of male L-shaped steel members and the legs of the pair of female L-shaped steel materials. By providing irregularities on the outer peripheral surface, these irregularities provide a virtual surface that connects the leg portions of the pair of male L-shaped steel materials and the boundary portions between the leg portions and the arm portions of the pair of male L-shaped steel materials (hereinafter, The filler filled in the filling space (hereinafter simply referred to as the first filling space) between the other steel pipe sheet pile main pipe and the other steel pipe sheet pile main pipe can be restrained. In particular, by providing a plate-like member, between the boundary virtual plane, the female L-shaped steel material, and one steel pipe sheet pile main pipe side where the female L-shaped steel material is provided (hereinafter referred to as a second filling space). Since the filler filled in can also be constrained, the shear strength can be improved. Further, the shear strength can be improved only by providing a plate-like member on a conventional steel pipe sheet pile main body by a method such as welding, and an increase in cost can be minimized. Furthermore, in this invention, since the structure of LL joint is employ | adopted for the female type | mold joint and the male type | mold joint, similarly to the joint structure of the said patent document 2, the excavation of the earth and sand in a fitting joint is performed reliably. In addition, the fitting joint can be reliably cleaned, and the filling material can be filled in the fitting joint densely. Therefore, the workability is dramatically improved and the quality is stable, and as described above, the adhesion between each L-shaped steel material and the filler can be ensured, and the shear strength of the joint can be improved. Reduction of construction cost and construction period can be realized.

Further , the width dimension Y along the outer circumferential direction of the steel pipe sheet pile main pipe of the plate-like member is a length dimension along the connecting direction of the steel pipe sheet pile main pipe of the leg portion of the male L-shaped steel material. Set to be less than twice X , regardless of the height direction of the steel sheet pile main pipe, the boundary virtual plane connecting the boundary portions between the leg portions and the arm portions of the pair of male L-shaped steel materials, A shear fracture surface is formed in the filler surrounded by the outer peripheral surface of the steel pipe sheet pile main pipe and the pair of female L-shaped steel materials.
According to such a configuration, the width of the concavo-convex portion of the plate-shaped member along the outer circumferential direction of the steel pipe sheet piles mains (width Y, hereinafter, simply referred to as the female side unevenness width) and, the steel pipe sheet pile mains Appropriate control of the mechanism of shear fracture by setting the length dimension of the uneven part of the male L-shaped steel leg along the connecting direction by the joint structure ( length dimension X, hereinafter simply referred to as the male side uneven length dimension) And can exhibit a stable shear strength.
That is, when the female-side uneven width dimension Y exceeds twice the male-side uneven length dimension X , a shear fracture surface may occur in the first filling space. The dimension along the connecting direction of the steel pipe sheet pile main joint in the first filling space along the connecting direction (hereinafter simply referred to as the main connecting direction dimension) is larger than the main connecting direction dimension of the second filling space. Depending on the position, the position of the shear fracture surface in the main pipe connecting direction is greatly displaced. For this reason, bending fracture accompanying pulling of the filler is caused, and a shear crack that is oblique to the vertical direction (hereinafter simply referred to as an oblique shear crack) is likely to occur, and the shear strength may be drastically reduced.
On the other hand, in the present invention, the female-side uneven width dimension Y is set to be less than twice the male-side uneven length dimension X , and the shear failure surface is not generated in the first filling space, and the shear failure is generated in the second filling space. By generating the surface, the displacement of the shear fracture surface due to the height in the main pipe connecting direction can be minimized. For this reason, generation | occurrence | production of an oblique shear crack can be suppressed and the stable shear strength can be exhibited.
In addition, it is preferable that the female-side uneven width dimension Y is 1 time or more of the male-side uneven length dimension X. That is, when the female-side uneven width dimension Y is less than 1 time, the effect of improving the shear strength as described above is sufficient. It is because it cannot be demonstrated to.

Furthermore, in the joint structure of the steel pipe sheet pile according to the present invention, the length X along the connecting direction of the steel pipe sheet pile main pipe in the joint structure in the leg portion of the pair of male L-type steel materials is the pair of female L-type steel materials. It is preferable that the leg portion is set to be longer than the length along the connecting direction.
According to such a configuration, the bending rigidity of the female joint is made higher than that of the male joint, and the male joint has a lower bending rigidity than that of the female joint, so that the male joint has high deformation performance. When the male joint is in a state of competing with each other, the male joint is deformed, so that the placement resistance is lowered and the placement is efficient.In addition, when the shear strength is exhibited, the male joint is deformed. , it can be suppressed by high female joint rigid than the male joint hand held down from the outside, can exhibit high shear strength.

In the steel pipe sheet pile joint structure according to the present invention, it is preferable that a thickness of the pair of male L-shaped steel materials is set smaller than a thickness of the pair of female L-shaped steel materials.
According to such a structure, when a joint competes at the time of placement, a male joint can be easily deformed, and placement resistance can be suppressed small. Moreover, by making the rigidity of the female joint higher than that of the male joint, deformation of the joint when exhibiting the shear strength can be suppressed, and a high shear strength can be exhibited.

On the other hand, the steel pipe sheet pile foundation of the present invention is characterized in that adjacent steel pipe sheet pile main pipes are connected by the joint structure of any one of the above steel pipe sheet piles.
According to such a configuration, as described above, by adopting the structure of the LL joint, it is possible to reliably excavate the earth and sand in the fitting joint, and to ensure cleaning of the fitting joint. In addition, the filler in the first filling space and the second filling space can be restrained. Therefore, the workability is dramatically improved and the quality is stable, the adhesion between each L-shaped steel material and the filler can be ensured, and the shear strength of the joint can be improved, thus reducing the construction cost. In addition, the construction period can be shortened.

  According to the steel pipe sheet pile joint structure and the steel pipe sheet pile foundation of the present invention as described above, the earth and sand in the fitting joint of the LL joint can be reliably excavated and the fitting joint can be reliably cleaned. In addition, the filler in the first filling space and the second filling space can be restrained. And a filler can be reliably filled between each L type | mold steel material of a female type | mold joint and a male type | mold joint, and adhesion of a filler and each L type | mold steel material can be improved, and the shear strength of a joint part can be improved. it can.

It is the top view and sectional drawing which show the steel pipe sheet pile foundation which concerns on embodiment of this invention. It is sectional drawing which shows the joint structure of the steel pipe sheet pile in the said steel pipe sheet pile foundation. It is a perspective view which expands and shows the fixing | fixed part of the male coupling of the said steel pipe sheet pile. It is a perspective view which expands and shows the fixing part of the female joint of the said steel pipe sheet pile, and a steel plate. It is a side view which shows the test body of the Example of this invention. It is a cross-sectional view which shows the test body of the said Example. 6 is a cross-sectional view showing a test body of Comparative Example 1. FIG. 6 is a cross-sectional view showing a test body of Comparative Example 2. FIG. It is a graph which shows the test result of an Example and Comparative Examples 1 and 2. It is a perspective view which expands and shows the fixing | fixed part of the steel plate of the steel pipe sheet pile which concerns on the modification of this invention.

  Hereinafter, each embodiment of the present invention will be described with reference to the drawings.

  In FIG. 1, a steel pipe sheet pile foundation 1 according to the present embodiment is a well foundation supporting a bridge pier provided near a river or a coast, and a plurality of steel pipe sheet piles 2 penetrating into the ground G on the riverbed or the seabed. These steel pipe sheet piles 2 are connected to each other via a joint portion 3 while being arranged side by side in a plane circle. As shown in FIG. 2, each steel pipe sheet pile 2 includes a steel pipe sheet pile main pipe 4 (hereinafter simply referred to as a main pipe 4) made of a circular steel pipe, a female joint 5 provided on a side surface of the main pipe 4, And a male joint 6 provided on the opposite side surface of the female joint 5. The joint portion 3 includes a female joint 5 of the steel pipe sheet pile 2A on one side (lower side in FIG. 2) and a steel pipe on the other side (upper side in FIG. 2) of the pair of steel pipe sheet piles 2 placed adjacent to each other. The male joint 6 of the sheet pile 2B is fitted to each other, and a cement-based room-temperature curable filler 7 such as mortar (hereinafter referred to as “mortar”) is formed in the spaces A and B formed by the fitted female joint 5 and the male joint 6. The steel pipe sheet piles 2A and 2B are connected to each other by simply filling the filler 7).

Female coupling 5 is configured to have a pair of female L-shaped steel 50 fixed to the outer surface of the main pipe 4 A in one of the steel pipe sheet pile 2A, the pair of female L-shaped steel 50 are each mains 4 The main pipe 4 is fixedly welded to the outer surface of A and has a leg portion 51 extending outward from the outer surface of the main tube A, and an arm portion 52 that is bent at a substantially right angle from the tip of the leg portion 51 and is formed in a substantially L-shaped cross section. Yes. The pair of female L-shaped steel members 50 are arranged inwardly such that the tips of the arm portions 52 approach each other, and have an opening 53 that receives the male joint 6 between the tips of these arm portions 52. Has been.

Male joint 6 is constituted by a pair of male L-shaped steel 60 which is secured to the outer surface of the main pipe 4 B of the other steel pipe sheet piles 2B, the pair of male L-type steel 60, respectively mains 4 welding is fixed to the outer surface of B from the main pipe 4 B outer surface and legs 61 extending outwardly, is formed to a substantially L-shape and an arm portion 62 bent substantially at a right angle from the tip of the leg portion 61 Yes. The pair of male L-shaped steel members 60 are arranged outwardly such that the tips of the respective arm portions 62 are separated from each other, and each leg portion 61 is inserted into the opening 53 of the female joint 5. Yes. Further, as shown in FIG. 3, the male L-shaped steel material 60 is formed of a striped steel plate having striped protrusions 63 (unevenness) on the surface where the pair of leg portions 61 face each other. Striped projections 63 are also formed on the outer surface of the arm portion 62 that is bent. Further, the length of the horizontal leg 61 of the male L-type steel 60 (connection direction of the steel pipe sheet pile main 4 B) is set to be longer than the length of the leg portion 51 of the female L-type steel 50. Further, the plate thickness of the male L-shaped steel material 60 is set smaller than the plate thickness of the female L-shaped steel material 50.

Further, a steel plate 8 (plate member) is provided between the leg portions 51 of the female joint 5 on the outer surface of one main pipe 4 (main pipe 4A in FIG. 2) so as to cover a portion from the upper end to the lower end of the region. Is fixed by welding. As shown in FIG. 4, the steel plate 8 is an arc plate having the same curvature as the main tube 4 by gradually bending a flat striped steel plate having striped protrusions 81 (unevenness) on the surface. Is formed. The steel plate 8 is fixed to one main pipe 4 so that the surface on which the protrusion 81 is provided faces the other main pipe 4. Moreover, the width dimension (dimension before bending (female side uneven width dimension)) Y along the arc direction of the steel plate 8 is the length dimension (male side) along the extending direction of the leg portion 61 of the male L-shaped steel material 60. It is set to a value less than twice the unevenness length dimension) X.

In the joint part 3 described above, by fitting the female joint 5 and the male joint 6 as shown in FIG. 2, the leg parts 61, the leg parts 61, and the arm parts 62 of the male L-shaped steel material 60 are connected. the boundary virtual surface connecting the boundary portion between, the position surrounded by the other outer surface of the main pipe 4 B, first filling space a filler 7 is filled is formed. A second filling space B in which the filler 7 is continuously filled in the first filling space A at a position surrounded by the boundary virtual surface, the outer surface of one main pipe 4A, and the female L-shaped steel material 50. Is formed.
At this time, by with striped protrusions 63 are formed on the surface of the male joint 6, the steel plate 8 which stripe-like projections 81 are formed on the surface is provided on one of the main pipe 4 A, male adhesion between the mold joint 6 and the filler 7 of the first filling space a, adhesion is enhanced each of the filler 7 of one of the main 4 a and a second filling space B, so that it can improve the shear strength of the joint portion 3 is It is configured.

  According to the present embodiment described above, the construction of the LL joint is adopted for the female joint 5 and the male joint 6, so that the earth and sand in the first filling space A and the second filling space B in the joint portion 3 are excavated. In addition, the interior of the spaces A and B can be reliably cleaned, and the filling of the filler 7 into the spaces A and B can be performed more reliably. Further, the protrusion 63 is formed on the leg portion 61 of the male joint 6 and the steel plate 8 having the protrusion 81 is provided between the pair of female joints 5, so that the first filling space A and the second filling space 5 are provided. Both fillers 7 in the filling space B can be restrained. Therefore, the workability is dramatically improved and the quality of the stable filler 7 can be ensured, and the adhesion between the female joint 5 and the male joint 6 and the filler 7 is enhanced, so that the shear strength of the joint portion 3 is increased. Can be improved. Further, when the steel pipe sheet pile foundation 1 receives a horizontal force due to an earthquake or earth pressure, a relative displacement in the vertical direction occurs between the steel pipe sheet piles 2, and a shear resistance force is exhibited at the joint portion 3. However, in this embodiment, even if the relative deformation amount of the joint portion 3 is increased, it is possible to continue to absorb a large amount of energy by exhibiting a stable shear strength, so that the damage to the entire steel pipe sheet pile foundation 1 is greatly reduced. can do.

  Moreover, since the female-side uneven width dimension Y is set to be less than twice the male-side uneven length dimension X, the area where the first filling space A is constrained by the unevenness is the second filling space B. It becomes larger than the area constrained by the unevenness, and since the stability of the first filling space A is superior, a shear fracture surface is not generated in the first filling space A, and the main pipe connection is made more than the first filling space A. A shear fracture surface can be generated in the second filling space B having a small size in the direction. Therefore, generation | occurrence | production of an oblique shear crack can be suppressed and the stable shear strength can be exhibited. Furthermore, since the plate | board thickness of the male L-type steel material 60 is smaller than the plate | board thickness of the female L-type steel material 50, while being able to suppress placement resistance, it can suppress the deformation | transformation of the joint part 3 at the time of exhibiting shear strength, and high shear I can demonstrate my power. And since the length of the connection direction of the steel pipe sheet pile main pipe | tube 4 of the leg part 61 of the male L-shaped steel material 60 is made longer than the length of the leg part 51 of the female L-type steel material 50, when exhibiting shear strength The deformation of the joint portion 3 can be suppressed, and a high shearing force can be exhibited.

Examples of the present invention will be described below.
In the present embodiment, the effect of providing the steel plate 8 having the protrusions 81 between the leg portions 51 of the female joint 5 and the female side uneven width dimension Y is less than twice the male side uneven length dimension X. The effect was confirmed.

First, the test specimen will be described. First, in producing the test body of the example, as shown in FIGS. 5 and 6, a pair of support columns 91 having an arcuate surface (arc surface) 92 having a radius of 400 mm to 800 mm on one surface face each other. A loading column 93 having an arc surface 94 having the same curvature as the arc surface 92 was prepared. Then, the male joint 6 made of a pair of male L-shaped steel members 60 was fixed to the arc surface 92 of one column 91 and the arc surface 94 of the loading column 93, respectively. The male L-shaped steel material 60 is formed by bending a striped steel plate having a protrusion 63 on the surface and a plate thickness of 6 mm, and a leg portion 61 having a width dimension (male side unevenness length dimension X) of 150 mm; The arm portion 62 has a width dimension of 90 mm. Further, the female joint 5 composed of a pair of female L-shaped steel members 50 is fixed to the arc surface 92 of the other support column 91 and the other arc surface 94 of the loading column 93, respectively, and the pair of female L-shaped steel materials. An arc plate-shaped steel plate 8 having the same curvature as the arc surface 92 was fixed between 50 and 50. The female L-shaped steel material 50 is formed by bending a steel plate having a thickness of 9 mm, and includes a leg portion 51 having a width dimension of 130 mm and an arm portion 52 having a width dimension of 90 mm. The steel plate 8 has protrusions 81 on the surface, and the female-side uneven width dimension Y is set to 250 mm, which is less than twice the male-side uneven length dimension X. In addition, the height dimension (dimension of the up-down direction of FIG. 5) of the male L-shaped steel material 60, the female L-shaped steel material 50, and the steel plate 8 is set to 1 m.
And while fixing a pair of support | pillar 91 to the ground G1 so that the loading pillar 93 can be arrange | positioned between them, while fitting the male coupling 6 and the female coupling 5 as shown in FIG.5 and FIG.6, it is 1st By filling the filling space A and the second filling space B with the filler 7, the test body of the example was completed.

  As shown in FIG. 7, the test body of Comparative Example 1 has three deformed reinforcing bars 95 each loaded with a column 91 instead of the steel plate 8 provided between the female L-shaped steel members 50 in the test body of the example. It has the same configuration as that of the test body of the example except that it is welded and fixed along the longitudinal direction of the column 93 and three deformed reinforcing bars 95 are also welded and fixed between the male L-shaped steel members 60. Yes.

  As shown in FIG. 8, the test body of Comparative Example 2 has protrusions 81 on the surface, and the female-side uneven width dimension Y is the male-side uneven length dimension X, instead of the steel plate 8 provided in the test body of the example. It has the same configuration as the test body of the example except that the steel plate 96 set to 500 mm, which is twice as large as the above, is provided.

  Next, the test method will be described. As shown in FIG. 5, the relative deformation (movement) amount of the male joint 6 and the female joint 5 and the load for pushing down, that is, the female joint 5 and the male joint 5 while pushing down the loading column 93 of the test body of the example downward. The shear force generated between the joints 6 was measured. The same measurement was performed on the specimens of Comparative Examples 1 and 2. FIG. 9 shows the relationship between the relative deformation amount of the joint in each specimen and the ratio to the maximum value of the shear force.

In Examples, it was confirmed that stable shear strength was exhibited. This is presumably because the occurrence of oblique shear cracks was suppressed because a shear fracture surface was generated in the region B1 in the second filling space B as indicated by a two-dot chain line in FIG.
On the other hand, in Comparative Example 1, it was confirmed that when the amount of relative deformation exceeds about 1.5 mm, the shear force suddenly decreases. As indicated by a two-dot chain line in FIG. 7, the shear fracture surface is formed in the region A1 in which the dimension in the connecting direction (vertical direction in FIG. 7) of the support column 91 and the loading column 93 is larger than the region B1 in the first filling space A. This is considered to be due to the occurrence of oblique shear cracks.
Moreover, in the comparative example 2, when the relative deformation amount exceeded 3 mm, it has confirmed that a shear force fell rapidly. This is considered because the shear fracture surface occurred in the region A2 where the dimension in the connecting direction of the support column 91 and the loading column 93 is larger than the region B1, as shown by the two-dot chain line in FIG. .
From the above, it can be confirmed that the shear strength of the example in which the steel plates 8 and 96 are provided between the female L-shaped steel members 50 and the comparative example 2 are superior to those of the comparative example 1 in which the deformed reinforcing bars 95 are provided at the same location. It was. Further, it was confirmed that the shear strength of the example in which the female-side uneven width dimension was less than twice the male-side uneven length dimension was superior to that of Comparative Example 2 in which it exceeded 2 times.

In addition, this invention is not limited to the said embodiment, Including other structures etc. which can achieve the objective of this invention, the deformation | transformation etc. which are shown below are also contained in this invention.
For example, in the said embodiment, although the steel pipe sheet pile foundation 1 used as a foundation of a bridge pier was demonstrated, the steel pipe sheet pile foundation in this invention can be utilized as a foundation which supports not only a bridge pier but arbitrary structures. is there. Moreover, the joint structure of the steel pipe sheet pile of the present invention is not limited to the steel pipe sheet pile foundation, but can be used as an arbitrary structure such as a retaining wall, a revetment structure, a connecting wall for underground structures, and its use is particularly limited. is not.
Further, as shown in FIG. 10, a steel plate 8 </ b> A obtained by bending a striped steel plate having protrusions 81 into a V shape may be provided instead of the steel plate 8. And it is good also as a shape which covers only a part of part from the upper end of the main pipe 4 to a lower end as the steel plates 8 and 8A.

In addition, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this. That is, the invention has been illustrated and described with particular reference to certain specific embodiments, but without departing from the spirit and scope of the invention, Various modifications can be made by those skilled in the art in terms of material, quantity, and other detailed configurations.
Therefore, the description limiting the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such is included in this invention.

  DESCRIPTION OF SYMBOLS 1 ... Steel pipe sheet pile foundation, 2, 2A, 2B ... Steel pipe sheet pile, 3 ... Joint part, 4 ... Steel pipe sheet pile main pipe, 5 ... Female joint, 6 ... Male joint, 7 ... Filler, 8, 8A ... Steel material ( Plate member), 50 ... female L-shaped steel, 51 ... leg, 52 ... arm, 60 ... male L-shaped steel, 61 ... leg, 62 ... arm, 63, 81 ... projections (unevenness).

Claims (4)

It is a joint structure of steel pipe sheet piles that connect the steel pipe sheet pile main pipes by fitting with one female joint and the other male joint among a pair of steel pipe sheet pile main pipes placed next to each other,
The female joint has a pair of female L-shaped steel members whose legs are fixed to the outer surface of the one steel pipe sheet pile main pipe, and the arm portions of the pair of female L-shaped steel materials are arranged inwardly toward each other. ,
The male joint has a pair of male L-shaped steel members whose legs are fixed to the outer surface of the other steel pipe sheet pile main pipe, and the arm portions of the pair of male L-shaped steel materials are arranged outwardly from each other. ,
The surfaces of the pair of male L-shaped steel members facing each other are provided with irregularities,
An area sandwiched between the legs of the pair of female L-shaped steel members on the outer peripheral surface of the one steel pipe sheet pile main pipe is provided with a plate-like member that covers at least a part of the area and has irregularities formed on the surface. It is,
The width dimension Y along the outer circumferential direction of the steel pipe sheet pile main body of the plate-like member is the length dimension X along the connection direction by the joint structure of the steel pipe sheet pile main pipe at the leg portion of the male L-shaped steel material. Boundary virtual plane that is set to be less than 2 times and connects the boundary portions between the leg portions and the arm portions of the pair of male L-shaped steel materials regardless of the height direction of the steel pipe sheet pile main pipe, and the one steel pipe sheet pile A steel pipe sheet pile joint structure , wherein a shear fracture surface is formed in a filler surrounded by an outer peripheral surface of a main pipe and the pair of female L-shaped steel materials . In the joint structure of the steel pipe sheet pile according to claim 1 ,
The length X along the connecting direction of the steel pipe sheet pile main joint in the leg portion of the pair of male L-shaped steel materials is longer than the length along the connecting direction in the leg portion of the pair of female L-shaped steel materials. The steel pipe sheet pile joint structure is characterized by being set longer. In the joint structure of the steel pipe sheet pile according to claim 1 or 2 ,
The steel pipe sheet pile joint structure is characterized in that a plate thickness of the pair of male L-shaped steel materials is set smaller than a plate thickness of the pair of female L-shaped steel materials. A steel pipe sheet pile foundation in which adjacent steel pipe sheet pile main pipes are connected by the joint structure of steel pipe sheet piles according to any one of claims 1 to 3 .

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