JP7453838B2 - Diaphragm for steel pipe concrete columns and steel pipe concrete columns - Google Patents

Description

The present invention relates to a diaphragm for a steel pipe concrete column and a steel pipe concrete column.

Conventionally, in columns of steel tube concrete (CFT) structures, diaphragms are provided at column-beam joints in order to transmit loads from steel beams. The diaphragm includes an outer diaphragm provided on the outside of the steel pipe, an inner diaphragm provided on the inside, and a through diaphragm. Examples of inner diaphragms are shown in FIGS. 7(1) and (2), and examples of through-diaphragms are shown in FIGS. 7(3) and (4). However, in the figure, numeral 1 is a steel pipe, numeral 2 is an inner diaphragm, numeral 3 is a through diaphragm, numeral 4 is a steel beam, numeral 5 is concrete, and numeral 6 is a pouring hole.

In the external diaphragm type, the diaphragm is on the outside of the steel pipe column, which affects the external shape and makes it difficult to fit. On the other hand, with the inner diaphragm type, the diaphragm is installed inside the steel pipe column, giving it a clean appearance, but there is a problem in that the diaphragm obstructs the filling of concrete when pouring concrete into the steel pipe column. Particularly on the lower surface of the diaphragm, air trapped in the concrete is difficult to escape, leaving air bubbles that impair the filling properties of the concrete, making it difficult to transfer sufficient load between the diaphragm and the concrete. This is a problem that occurs both when concrete is forced in from below and when concrete is poured from above using a tremie pipe or the like.

As a conventional technique for solving this problem, a method is known in which, for example, an air vent hole is made at the end of a diaphragm and a vibrator is applied to the concrete to vent air (see, for example, Patent Documents 1 and 2). However, it is extremely difficult to sufficiently remove air trapped under the horizontal diaphragm.

Japanese Patent Application Publication No. 6-212733 Japanese Patent Application Publication No. 6-288002

The present invention has been made in view of the above, and an object of the present invention is to provide a diaphragm for a steel pipe concrete column and a steel pipe concrete column from which air accumulated on the lower side can be easily discharged.

In order to solve the above problems and achieve the objects, a diaphragm for a steel pipe concrete column according to the present invention is provided on the inner circumferential surface of a steel pipe concrete column having a steel pipe and concrete filled inside the steel pipe. The inner diaphragm is fixed and has a substantially horizontal plate-like diaphragm body, an air vent hole provided vertically through the diaphragm body in order to discharge air from the lower side of the diaphragm body to the upper side, and It is characterized by comprising an inclined part formed on the lower surface and inclined upward as it approaches the air vent hole.

In addition, another diaphragm for a steel pipe concrete column according to the present invention, in the above-described invention, further includes a casting hole provided vertically penetrating the center side of the diaphragm body for pouring concrete, and an air vent hole. is characterized in that it is provided on the peripheral edge side of the diaphragm body.

Further, another diaphragm for a steel pipe concrete column according to the present invention is characterized in that, in the above-mentioned invention, the air vent hole in the upper surface of the diaphragm body is located at a higher position than the casting hole.

Further, in the above-mentioned invention, in another diaphragm for a steel pipe concrete column according to the present invention, the shape of the lower surface of the diaphragm body is formed into a concave concave shape, a concave shape, or an uneven shape with a concave top at the center of the diaphragm body. It is characterized by

Moreover, the steel pipe concrete column according to the present invention is characterized by being equipped with the above-mentioned diaphragm for a steel pipe concrete column.

According to the diaphragm for a steel pipe concrete column according to the present invention, the inner diaphragm is fixed to the inner peripheral surface of a steel pipe in a steel pipe concrete column having a steel pipe and concrete filled inside the steel pipe, and the inner diaphragm is a substantially horizontal plate. a shaped diaphragm body; an air vent hole provided vertically through the diaphragm body to discharge air from the bottom side of the diaphragm body upwards; Since the slanted portion is provided with the slanted portion slanted toward the diaphragm, air accumulated under the diaphragm body during concrete filling can be easily discharged to the top of the diaphragm body.

Further, according to another diaphragm for a steel pipe concrete column according to the present invention, the diaphragm further includes a casting hole that vertically penetrates the center side of the diaphragm body for pouring concrete, and the air vent hole is formed in the diaphragm. Since it is provided on the peripheral side of the main body, it has the effect that concrete can be filled through the casting hole on the center side and air can be discharged through the air vent hole on the peripheral side.

Further, according to another diaphragm for steel pipe concrete columns according to the present invention, the air vent hole on the upper surface of the diaphragm body is located at a higher position than the casting hole, so that the air vent hole is placed at a higher position than the casting hole. This has the effect of preventing the air vent hole from being blocked by concrete overflowing upward from the hole.

Further, according to another diaphragm for a steel pipe concrete column according to the present invention, the shape of the lower surface of the diaphragm body is formed in a concave concave shape, a concave shape, or an uneven shape with the center of the diaphragm body as the concave top. This has the effect that the air below the main body can be easily guided to the air vent hole.

Furthermore, since the steel pipe concrete column according to the present invention includes the above-described diaphragm for steel pipe concrete columns, it is possible to obtain a steel pipe concrete column with improved filling properties of concrete below the diaphragm body.

FIG. 1 is a diagram showing a first embodiment of a diaphragm for a steel pipe concrete column and a steel pipe concrete column according to the present invention, in which (1) is a plan sectional view and (2) is a side sectional view. FIG. 2 is a side sectional view showing Embodiment 2 of a diaphragm for a steel pipe concrete column and a steel pipe concrete column according to the present invention. FIG. 3 is a side sectional view showing Embodiment 3 of a diaphragm for a steel pipe concrete column and a steel pipe concrete column according to the present invention. FIG. 4 is a side sectional view showing Embodiment 4 of a diaphragm for a steel pipe concrete column and a steel pipe concrete column according to the present invention. FIG. 5 is a side sectional view showing Embodiment 5 of a diaphragm for a steel pipe concrete column and a steel pipe concrete column according to the present invention. FIG. 6 is a schematic perspective view showing an example of the bottom shape of the diaphragm. Figure 7 shows an example of a conventional CFT column-beam joint, where (1) is a plan cross-sectional view of the inner diaphragm type, (2) is a side cross-sectional view of (1), and (3) is the through-diaphragm type. (4) is a side sectional view of (3).

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a diaphragm for a steel pipe concrete column and a steel pipe concrete column according to the present invention will be described in detail below based on the drawings. Note that the present invention is not limited to this embodiment.

(Embodiment 1)
First, Embodiment 1 of the present invention will be described.
As shown in FIG. 1, the steel pipe concrete column diaphragm 100 according to the first embodiment is a steel inner diaphragm fixed to the inner peripheral surface of a square steel pipe 12 in the steel pipe concrete column 10. The steel pipe concrete column 10 includes concrete 14 filled inside a steel pipe 12. A steel beam 4 made of H-shaped steel is connected to the diaphragm 100 from the outside of the steel pipe 12. In this embodiment, the case where the steel pipe 12 is a square steel pipe will be described as an example, but the present invention is not limited to the shape of the steel pipe, and may be, for example, a circular steel pipe.

The diaphragm 100 includes a diaphragm body 16 made of a substantially rectangular steel plate in plan view, a concrete casting hole 18, an air vent hole 20, and an inclined portion 22. The upper surface of the diaphragm body 16 is horizontal.

The concrete pouring hole 18 is a hole for pouring the concrete 14, and is provided to vertically penetrate the center (center) of the diaphragm body 16. In addition, in this embodiment, the case where the shape of the concrete pouring hole 18 is circular will be explained as an example, but the shape is not limited to this, and may be rectangular or other polygonal shape. The installation position of the concrete pouring hole 18 is not limited to the center of the diaphragm body 16, but may be placed anywhere in the diaphragm body 16, and the number of concrete pouring holes 18 may be one or more.

The air vent hole 20 is a small hole for discharging air below the diaphragm body 16 to the upper side, and is provided by penetrating the peripheral side of the diaphragm body 16 in the vertical direction. In this embodiment, it is provided on each side close to the four corners of the diaphragm body 16. The air vent hole 20 may also be used as a scallop when welding the diaphragm body 16 to the steel pipe 12. Note that in this embodiment, the shape of the air vent hole 20 is explained as a circle, but the shape is not limited to this and may be rectangular or any other polygon. The installation position of the air vent hole 20 is not limited to the peripheral side of the diaphragm body 16, and it may be anywhere on the diaphragm body 16, and the number of air vent holes may be one or more.

The inclined portion 22 is formed on the lower surface of the diaphragm body 16, and is a portion that slopes upward as it approaches the air vent hole 20 from the concrete placement hole 18. Therefore, the lower surface of the diaphragm body 16 has a substantially trapezoidal shape when viewed from the side. A method for forming the inclined portion 22 on the lower surface of the diaphragm body 16 includes, for example, cutting a steel plate constituting the diaphragm body 16 and changing the plate thickness from the center to the periphery of the diaphragm body 16 to create the slope. Can be used. In addition, when providing the concrete pouring hole 18 in the center of the diaphragm main body 16 as in this embodiment, it is preferable to perform processing to create an inclination so that the center side is higher.

According to the above configuration, the lower surface of the diaphragm body 16 is inclined upward by the inclined portion 22, and the air vent hole 20 is provided at a high position on the lower surface, so that the concrete 14 is poured into the steel pipe 12 from the concrete pouring hole 18. Air accumulated on the lower surface of the diaphragm body 16 during filling naturally flows upward and escapes upward through the air vent hole 20. Therefore, the air accumulated on the lower side of the diaphragm body 16 can be easily discharged to the upper side of the diaphragm body 16. This improves the filling properties of the concrete 14 on the lower surface of the diaphragm main body 16, making it possible to construct a good frame with few concrete voids.

(Embodiment 2)
Next, a second embodiment of the present invention will be described.
As shown in FIG. 2, a diaphragm 200 for a steel pipe concrete column according to the second embodiment is the same as the first embodiment described above, except that a plurality of raised portions are provided. Specifically, instead of the inclined part 22 formed on the lower surface of the diaphragm main body 16 of the first embodiment, two inclined parts 24 and 26 having different inclination directions are used.

The inclined portion 24 is a portion that is inclined upward as it approaches the air vent hole 20 on the peripheral edge side from the V-shaped top portion 28 that is pointed downward in side view. The sloped portion 26 is a portion that slopes upward as it approaches the central concrete casting hole 18 from the top portion 28 . By doing so, the concrete casting hole 18 can also be used as an air vent hole.

According to the above configuration, since the lower surface of the diaphragm body 16 is inclined upward by the inclined parts 24 and 26, the air accumulated under the diaphragm body 16 when filling the concrete 14 from the concrete pouring hole 18 is removed. It naturally flows upward and escapes upward through the air vent holes 20 on the peripheral side and the concrete casting hole 18 in the center. Therefore, the air accumulated on the lower side of the diaphragm body 16 can be easily discharged to the upper side of the diaphragm body 16.

Note that a plurality of apexes 28 on the lower surface of the diaphragm body 16 may be arranged at intervals to form a plurality of raised portions that are jagged in side view, and the air vent holes 20 may be provided in these portions. This can prevent the diaphragm main body 16 from moving far away from the axis of the flange of the steel beam 4. Further, when the column cross section is large, by doing so, the thickness of the diaphragm body 16 can be prevented from becoming too small. The direction of inclination may be in one direction, may be in two directions depending on the location, may be axially symmetrical, or may be in any other free form.

FIG. 6 shows an example of the shape of the lower surface of the diaphragm body 16. (1) is conical, (2) is pyramidal, (3) is chevron-shaped, and (4) is uneven. The lower surface of the diaphragm body 16 may be set in the shape shown in this figure (concave concave shape, concave shape, or uneven shape with the center of the diaphragm body 16 as the concave top).

(Embodiment 3)
Next, a third embodiment of the present invention will be described.
As shown in FIG. 3, a diaphragm 300 for a steel pipe concrete column according to the third embodiment is a modification of the second embodiment, in which the diaphragm body 16 itself is subjected to an inclination process. Specifically, in the second embodiment, the diaphragm main body 16 is sloped into an upwardly convex substantially conical shape. Along with this, the air vent hole 20 on the peripheral side and the corresponding slope part 24 are omitted, while the slope part 26 and the concrete casting hole 18 in the center are left. Therefore, the concrete casting hole 18 also serves as an air vent hole.

Any method may be used for tilting the diaphragm body 16. For example, the steel plate constituting the diaphragm body 16 may be bent, the steel plate may be welded at an angle, or the surface of the steel plate may be welded. or a combination of them.

According to the above configuration, since the lower surface of the diaphragm body 16 is inclined upward by the inclined portion 26, the air accumulated under the diaphragm body 16 when filling the concrete 14 from the concrete pouring hole 18 is naturally removed. It flows upward and exits upward through the central concrete pouring hole 18. Therefore, the air accumulated on the lower side of the diaphragm body 16 can be easily discharged to the upper side of the diaphragm body 16.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described.
As shown in FIG. 4, a diaphragm 400 for a steel pipe concrete column according to the fourth embodiment is a modification of the second embodiment, in which the diaphragm body 16 itself is subjected to an inclination process. Specifically, in the second embodiment, the diaphragm main body 16 is sloped into a substantially conical shape with a downward convexity. Accordingly, the inclined part 26 corresponding to the central concrete casting hole 18 is omitted, while the air vent hole 20 on the peripheral side and the corresponding inclined part 24 are left.

Any method may be used for tilting the diaphragm body 16. For example, the steel plate constituting the diaphragm body 16 may be bent, the steel plate may be welded at an angle, or the surface of the steel plate may be welded. or a combination of them.

According to the above configuration, since the lower surface of the diaphragm body 16 is inclined upward by the inclined portion 24, the air accumulated under the diaphragm body 16 when filling the concrete 14 from the concrete pouring hole 18 is naturally removed. The air flows upward and escapes upward through the air vent hole 20 on the peripheral edge side. Therefore, the air accumulated on the lower side of the diaphragm body 16 can be easily discharged to the upper side of the diaphragm body 16.

(Embodiment 5)
Next, Embodiment 5 of the present invention will be described.
As shown in FIG. 5, a diaphragm 500 for a steel pipe concrete column according to the fifth embodiment differs from the first embodiment described above in that the upper surface of the diaphragm body 16 is not made horizontal, and the periphery of the air vent hole 20 is placed in concrete. It is made higher than the hole 18.

When providing an air vent hole 20 in addition to the concrete casting hole 18, if the upper surface of the diaphragm body 16 is higher than the concrete casting hole 18 around the air vent hole 20, the efficiency of the air vent hole 20 will be improved. Therefore, it is preferable. Because the area around the air vent hole 20 is high, when the concrete 14 press-fitted from below rises from the concrete placement hole 18 to the top of the diaphragm body 16, the air vent hole 20 is blocked from above before the air escapes from below. You can prevent it from happening.

In addition, in the above embodiments 2 to 4, the upper surface of the diaphragm body 16 is not made horizontal and the area around the air vent hole 20 is made higher than the concrete casting hole 18. It is also applicable to the case where holes 20 are provided. Even in this case, the same effects as described above can be achieved.

As explained above, according to the diaphragm for a steel pipe concrete column according to the present invention, the inner diaphragm fixed to the inner circumferential surface of the steel pipe in a steel pipe concrete column having a steel pipe and concrete filled inside the steel pipe. There is a diaphragm body in the shape of a substantially horizontal plate, an air vent hole provided vertically through the diaphragm body to discharge air from the bottom side of the diaphragm body to the top, and an air vent hole formed on the bottom surface of the diaphragm body. Since the slanted portion is inclined upward as it approaches the hole, air that accumulates below the diaphragm body during concrete filling can be easily discharged to the top of the diaphragm body.

Further, according to another diaphragm for a steel pipe concrete column according to the present invention, the diaphragm further includes a casting hole that vertically penetrates the center side of the diaphragm body for pouring concrete, and the air vent hole is formed in the diaphragm. Since it is provided on the peripheral side of the main body, concrete can be filled through the casting hole on the center side and air can be discharged through the air vent hole on the peripheral side.

In addition, with another diaphragm for steel pipe concrete columns according to the present invention, the air vent hole on the top surface of the diaphragm body is located higher than the pouring hole, so it is possible to prevent the air vent hole from being blocked by concrete that has overflowed from the pouring hole to the top before the air escapes from the underside of the diaphragm body.

Further, according to another diaphragm for a steel pipe concrete column according to the present invention, the shape of the lower surface of the diaphragm body is formed in a concave concave shape, a concave shape, or an uneven shape with the center of the diaphragm body as the concave top. Air under the main body can be easily guided to the air vent hole.

Furthermore, since the steel pipe concrete column according to the present invention includes the above-described diaphragm for a steel pipe concrete column, it is possible to obtain a steel pipe concrete column in which the filling property of the concrete below the diaphragm body is improved.

As described above, the diaphragm for a steel pipe concrete column and the steel pipe concrete column according to the present invention are useful for a steel pipe concrete column equipped with an inner diaphragm, and in particular, can easily remove air accumulated under the diaphragm during concrete filling. Suitable for draining.

4 Steel beam 10 Steel pipe concrete column 12 Steel pipe 14 Concrete 16 Diaphragm body 18 Concrete casting hole 20 Air vent hole 22, 24, 26 Inclined part 28 Top part 100-500 Diaphragm for steel pipe concrete column

Claims (4)

An inner diaphragm fixed to the inner peripheral surface of the steel pipe in a steel pipe concrete column having a steel pipe and concrete filled inside the steel pipe,
a diaphragm body having a substantially horizontal plate shape; an air vent hole provided vertically passing through the diaphragm body for discharging air from the lower side of the diaphragm body upward ; The diaphragm body includes an inclined portion that is inclined upward as it approaches the air vent hole, and a casting hole that is provided vertically through the center side of the diaphragm body for pouring concrete, and the air vent hole is provided with: A diaphragm for a steel pipe concrete column, characterized in that the diaphragm is provided on the peripheral side of the diaphragm main body . The diaphragm for a steel pipe concrete column according to claim 1 , wherein the air vent hole in the upper surface of the diaphragm body is located at a higher position than the casting hole. The diaphragm for a steel pipe concrete column according to claim 1 or 2 , wherein the shape of the lower surface of the diaphragm body is formed in a concave concave shape, a concave shape, or an uneven shape with a concave apex at the center of the diaphragm body. . A steel pipe concrete column comprising the diaphragm for a steel pipe concrete column according to any one of claims 1 to 3 .

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