JPH0619147B2 - Column base structure - Google Patents

Description

TECHNICAL FIELD The present invention relates to a column base structure of a steel frame structure or a steel frame reinforced concrete structure.

[Conventional technology]

When a conventional steel column is erected on a concrete foundation,
A method is generally used in which a base plate made of a steel plate is welded to a column base of a steel frame column and then fixed by anchor bolts embedded in a concrete foundation. First
FIG. 13 is a sectional view of an essential part showing an example of a conventional column base structure. In the figure, first, a base plate 2 made of a steel plate is integrally joined to a column 1 made of a steel material by welding, and is placed on a concrete foundation 3 which has been placed in advance via a partial mortar 4. In this case, since the predetermined number of anchor bolts 5 are embedded in the concrete foundation 3, positioning is performed by the bolt holes 6 formed in the base plate 2.
After that, for example, the wooden frame 7 is arranged, and the mortar 8 is filled between the base plate 2 and the concrete foundation 3. After the mortar 8 is sufficiently solidified, the anchor bolt 5 is fitted with the washer 9 and the nut 10 is fastened to fix the pillar 1.

[Problems to be solved by the invention]

FIG. 14 is a plan view of the arrangement of columns in an architectural building. In such a column arrangement, when the conventional column base structure shown in FIG. 13 is used, the side column used for the side part of the building.
20 and the corner post 21 used for the corners, the 13th
As is clear from the figure, since the side surface of the concrete foundation 3 projects from the center of the pillar 1 to the outside of the building, there is a problem that it is extremely difficult to perform on-site work. That is, the side pillar
The 20 and the corner post 21 are usually provided close to the adjacent land boundary line 22, especially in a working environment where the adjacent land boundary line 22 cannot be entered at all into the adjacent ground,
Not only the work of placing the concrete foundation 3 shown in FIG. 13 but also the work of installing the pillar 1 and the work of filling the mortar 8 must be performed in a narrow working space, and not only the workability is extremely deteriorated. The quality of the concrete foundation 3, the mortar 8 and the like after being placed will also be affected. In addition, since the side surface of the concrete foundation 3 projects outward from the building from the center of the pillar 1 as described above, it may be necessary to secure an unnecessarily large distance from the adjacent land, and There is a problem that it is reduced and the site area cannot be used effectively.

The present invention solves the problems existing in the above-mentioned prior art, improves quality and other characteristics such as rigidity and proof stress against bending moment applied to a column, improves workability at a construction site, and expands a building area. The purpose is to provide a column base structure that enables effective use of the site.

[Means for solving problems]

In order to solve the problems existing in the above-mentioned prior art, in the invention of the present application, 1 which is joined to the leg portion of the column made of steel is used.
In a column base structure in which a base plate made of one or more steel plates and a concrete foundation are joined via anchor bolts embedded in the concrete foundation, the center of the projected contour of the base plate with respect to the horizontal plane and the projected contour of the column with respect to the horizontal plane. The technical means is employed in which the center is formed eccentrically and the out-of-plane deformation preventing means of the base plate is provided on the non-eccentric side of the base plate.

[Work]

With the above configuration, in the side pillar and corner pillar portions,
The dimension from the center of the projected contour to the plane of the pillar to the outer surface of the concrete foundation can be significantly shortened compared to that in the central pillar, and a working space with the adjacent land can be secured.

Further, it is expected that the non-eccentric side of the base plate prevents the so-called out-of-plane deformation in which the upper surface is convex and deforms, and the stability of the column can be secured.

As the out-of-plane deformation preventing means, means for restricting the base plate by increasing the projected area of the washer to be inserted in the anchor bolt on the plane, means for increasing the number of anchor bolts installed on the non-eccentric side of the base plate, Alternatively, there is a means for reinforcing the base plate on the non-eccentric side by a rib provided in the vertical direction between the column and the base plate, which can be appropriately selected in consideration of the dimensions and shapes of the column and the base plate.

〔Example〕

1 and 2 are a main-portion cross-sectional view and a main-portion cross-sectional plan view, respectively, showing an embodiment of the invention of the present application, and FIG. 1 shows a cross section taken along the line AA in FIG. In both figures, the same parts are designated by the same reference numerals as in FIG. As shown in both figures, the pillar 1 and the base plate 2 are integrally formed, for example, by welding or casting while the center of the projected contour of the pillar 1 with respect to the horizontal plane and the center of the projected contour of the base plate 2 with respect to the horizontal surface are eccentric. To join.

The anchor bolt 5 on the non-eccentric side is provided with a washer 9a having a substantially L-shaped projected contour with respect to the horizontal plane. That is, the washer 9a has a larger projected area with respect to the horizontal plane than the washer 9 that is interposed in the eccentric anchor bolt 5.

With the above configuration, as is apparent from FIGS. 1 and 2, the dimension from the center of the pillar 1 to the right side surface of the concrete foundation 3 can be shortened. That is, it is possible to secure a working space to the right of the concrete foundation 3 in both the above figures.

Further, since the fastening pressure can be applied to the upper surface of the non-eccentric side base plate 2 over a wide range, it is possible to prevent the out-of-plane deformation of the base plate 2.

Next, FIGS. 3 and 4 are explanatory views of the out-of-plane deformation, and the same portions are denoted by the same reference numerals as those in FIGS. 1 and 2. If the center of the projected contour of the column 1 with respect to the horizontal plane and the center of the projected contour of the base plate 2 with respect to the horizontal plane are eccentrically formed, the distance between the outer surface of the column 1 and the edge of the base plate 2 becomes unequal. That person distance L ₂ in the eccentric-side non-eccentric side than the distance L ₁ in (column 1 of the right side) (left column 1) is large as shown in Figure 3. Therefore, when a bending moment such as M acts on the pillar 1, the base plate 2 may cause so-called out-of-plane deformation in which the base plate 2 is deformed with its upper surface convex as shown in FIG. When such an out-of-plane deformation occurs, the stress generated in the pillar 1 cannot be smoothly transmitted to the concrete foundation 3, which may cause deformation of the entire building, which is inconvenient.

In this respect, in the invention of the present application, as shown in FIG. 1 and FIG. 2, the washer 9a to be inserted in the anchor bolt 5 on the non-eccentric side is more than the washer 9 to be inserted in the anchor bolt 5 on the eccentric side. Since the out-of-plane deformation preventing means is formed by forming a large projected area with respect to the horizontal plane, the undesired phenomenon shown in FIG. 4 does not occur.

Next, FIG. 5 and FIG. 6 are a side view and a sectional plan view of an essential part showing another embodiment of the invention of the present application, and the same parts are designated by the same reference numerals as those in the above drawings. In both figures, the number of anchor bolts 5 provided on the non-eccentric side is greater than the number of anchor bolts 5 provided on the eccentric side.

With the above configuration, the restraining force on the base plate 2 on the non-eccentric side can be increased, and the occurrence of out-of-plane deformation of the base plate 2 can be prevented as in the above-described embodiment.

FIG. 7 and FIG. 8 are a side view and a cross-sectional plan view of an essential part showing still another embodiment of the invention of the present application, and the same parts are designated by the same reference numerals as those in the above drawings. In both figures, ribs 11 are provided on the side surface of the pillar 1 to reinforce the base plate 2. Then, the projected area of the rib 11a on the non-eccentric side to the vertical surface is made larger than that of the rib 11b on the eccentric side.

With the above configuration, the out-of-plane deformation of the base plate 2 on the non-eccentric side can be prevented, as in the above-described embodiment.

In the above-mentioned embodiment, the example in which the base plate is formed by one steel plate is shown, but it may be formed by superposing two or more sheets, or by superposing a plurality of steel sheets via a rib in the middle. The action is the same. Further, the shape and size of the washer used as the out-of-plane deformation preventing means are not limited to those in the above-mentioned embodiment, and can be freely selected according to the shape and size of the column and the base plate. Also, the diameter of the anchor bolt on the non-eccentric side may be increased, the number of ribs installed may be increased, and any known means other than the above-mentioned embodiment may be appropriately used as the means for preventing the out-of-plane deformation of the base plate on the non-eccentric side. It can be selected and used.

Next, FIG. 9 to FIG. 12 are cross-sectional plan views of the essential parts showing still another embodiment of the invention of the present application, and the same portions are the embodiment shown in FIG. 1 to FIG. 8 and FIG. And the same reference numerals as in the example of FIG. 9 to 11
The figure shows the case where the columns 1 are a cylindrical steel pipe, an H-shaped steel and an assembled column, respectively, and all are for side columns. Further, FIG. 12 is for a corner post in which the pillar 1 is made of a rectangular steel pipe.
The center of the contour with respect to the horizontal plane is formed eccentrically in the upper right corner of the base plate 2.

Although the out-of-plane deformation preventing means is not shown in FIGS. 9 to 12, the out-of-plane deformation preventing means as in the above embodiment is provided on the non-eccentric side of the base plate 2. And

〔The invention's effect〕

Since the invention of the present application has the configuration and operation as described above, by using it for side pillars and corner pillars,
Since the working space can be secured without deteriorating the original characteristics of the column base, there is an effect that workability can be significantly improved and the construction period can be shortened. Also, since the span of the pillar can be increased, the building area can be increased and the site can be effectively used.

[Brief description of drawings]

1 and 2 are cross-sectional views of a main part and a cross-sectional plan view of the main part showing an embodiment of the invention of the present application, and FIGS. 3 and 4 are explanatory views for out-of-plane deformation, FIG. 5 and FIG. 6 is a side view of a main part and a cross-sectional plan view of the main part showing another embodiment of the present invention, and FIGS. 7 and 8 are cross-sectional side views of the main part showing still another embodiment of the present invention. FIG. 9 to FIG. 12 are cross-sectional plan views of essential parts showing still another embodiment of the invention of the present application, and FIG. 13 is a cross-sectional view of essential parts showing an example of a conventional column base structure. Figures and 14 are plan views of the pillars of a building. 1: pillar, 2: base plate, 3: concrete foundation,
5: Anchor bolt, 9, 9a: Washer, 11, 11a, 11b: Rib.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Isamu Yamamoto 1-9-1 Kitahama, Wakamatsu-ku, Kitakyushu, Fukuoka Prefecture Hitachi Metals Co., Ltd. Wakamatsu Factory (72) Inventor Kuniaki Sato 1-2-chome, Moto-Akasaka, Minato-ku, Tokyo No. 7 Kashima Construction Co., Ltd. (72) Inventor Yoshihiro Nakamura 1-2-7 Moto-Akasaka, Minato-ku, Tokyo Kajima Construction Co., Ltd. (72) Inventor Akio Tomita 1-2-Chome, Moto Akasaka, Minato-ku, Tokyo No. 7 within Kashima Construction Co., Ltd. (56) Reference Japanese Patent Laid-Open No. 61-162635 (JP, A) Actual exploitation Sho 49-89920 (JP, U) Actual exploitation Sho 62-194806 (JP, U)

Claims (4)

[Claims] 1. A column base structure in which a base plate made of one or a plurality of steel plates joined to a leg portion of a steel column and a concrete foundation are joined together through anchor bolts embedded in the concrete foundation. And a center of the projected contour of the column with respect to the horizontal plane are eccentrically formed, and an out-of-plane deformation preventing means of the base plate is provided on the non-eccentric side of the base plate. Construction. 2. A projection area of a washer for interposing the out-of-plane deformation preventing means of the base plate on the anchor bolt on the non-eccentric side, or a projected area and thickness on the plane for the anchor bolt on the eccentric side. The column base structure according to claim 1, which is formed by making it larger than those of the washers. 3. The out-of-plane deformation preventing means of the base plate is formed by making the number and / or diameter of anchor bolts installed on the non-eccentric side larger than those of the anchor bolts on the eccentric side. The column base structure according to item 1. 4. At least the number of ribs provided in the vertical direction between the column on the non-eccentric side and the base plate, the projection area with respect to the vertical surface, the projection area with respect to the vertical surface, and the thickness. The column base structure according to claim 1, wherein the column base structure is formed by making one larger than those on the eccentric side.