COLUMN SHOE

Abstract

 Column shoe (1) for attaching concrete columns to a foundation or to another concrete column, said column shoe (1) comprising a bolt casing (2) with an open side, said bolt casing (2) comprising a side plate (5) forming the side of the bolt casing (2), said side plate (5) comprising an opening (11) for attaching a nut, a bottom plate (3) forming the bottom of the bolt casing (2), said bottom plate (3) comprising a bolt hole (10), and a top plate (4) forming the top of the bolt casing (2). The column shoe (1) further comprises at least one main bond means (6) attached to bolt casing (2) for attaching the column shoe (1) and the concrete column to each other. The column shoe (1) additionally comprises at least one horizontal back bond means (8) attached to the outer surface of the side plate (5) at two points (9). The part of the horizontal back bond means (8) between the attachment points (9) is located at a distance from the side plate (5). The column shoe (1) comprises a vertical back bond means (7) attached to the horizontal back bond means (8) between the attachment points (9) so that the vertical back bond means (7) is located between the horizontal back bond means (8) and the side plate (5).

Description

[0001] The object of the present invention is a column shoe as defined in the preamble of claim 1 for attaching concrete columns to a foundation or to another concrete column.

[0002] Column shoes are used for attaching concrete columns to a foundation. A column shoe typically comprises a bolt casing with one side open, which bolt casing comprises a bottom plate provided with a bolt hole and a top plate as well as a side plate attached to them. Column shoe further comprises bar-shaped dowel parts for attaching a column shoe and a concrete column to each other. Column shoes are placed during casting at the corners of the lower end of a concrete column. Column shoes of a concrete column are attached to the bolts in the attachment foundation. Column shoes can also be used for extending concrete columns with another concrete column. In this case the one concrete column comprises a bolt to which a column shoe of the other concrete column is attached to.

[0003] A column shoe mainly transmits vertical forces with the direction of the bolt. In a column shoe, main bond means and a bolt are disposed eccentrically relative to one another, due to which compressive force to be transmitted from the concrete column to the bolt does not transmit directly, but it has to be transmitted in a horizontal direction. This induces a bending moment in the column shoe, which bending moment tends to release the lower edge of the column shoe from the concrete column. When the bolt joining the column shoe is under tensile force, tends the upper edge of the bolt casing of the column shoe to release itself from the concrete column due to eccentric moment. This induces also harmful bending stress on the main bond means of a column shoe.

[0004] The aim of the present invention is to provide a column shoe by means of which the above problems can be reduced.

[0005] The aim of the invention is achieved by means of the column shoe of claim 1.

[0006] Column shoe according to the invention comprises a bolt casing with an open side, said bolt casing comprising a side plate forming the side of the bolt casing, said side plate having an opening for installing a nut, a bottom plate forming the bottom of the bolt casing, said bottom plate having a bolt hole, and a top plate forming the top of the bolt casing. Column shoe additionally comprises at least one main bond means attached to the bolt casing for attaching the column shoe and the concrete column to each other. Column shoe further comprises at least one horizontal back bond means attached to the outer surface of the side plate at two points. The part of the horizontal back bond means between the attachment points is located at a distance from the side plate. A vertical back bond means is arrangeable between the horizontal back bond means and the side plate, or the column shoe comprises a vertical back bond means attached to the horizontal back bond means between the attachment points so that the vertical back bond means is located between the horizontal back bond means and the side plate.

[0007] With the invention the problem of the prior art is reduced, in which problem internal horizontal forces due to structural functioning of a column shoe tend to release a column shoe from a concrete and to induce harmful additional stress on the structure of a column shoe. Horizontal back bond means and vertical back bond means in the back part of the column shoe of the invention connect the column shoe to the concrete of the column, when a bolt joining to column shoe is affected by compression force or tensile force. Thus the structure formed by the horizontal back bond means and the vertical back bond means attaches and connects the column shoe to concrete of the column against harmful horizontal eccentricity forces. The forming of the casing and the horizontal back bond means of column shoe together with the vertical back bond means, make it possible to achieve a structure which solidly connects the column shoe to concrete.

[0008] In the following, the invention will be described in detail by the aid of examples by referring to the attached drawings, wherein

Fig. 1 presents a column shoe according to one embodiment of the invention in side view, and

Fig. 2 presents a section A-A of column shoe of Fig. 1 and

Fig. 3 presents a section B-B of column shoe of Fig. 1.

[0009] A column shoe 1 according to figures is used for attaching a concrete column to a foundation or for extending a concrete column with another concrete column. The joint of two concrete columns or of concrete column and foundation comprises column shoes, which have been placed in the element mould of a concrete column before its casting, and a corresponding amount of bolts placed on the foundation mold. The joint is provided by attaching the column shoes of the concrete column to anchor bolts with nuts.

[0010] Column shoe 1 comprises a bolt casing 2 with one side open. The bolt casing 2 comprises a side plate 5 forming the side of the bolt casing 2, a bottom plate 3 forming the bottom of the bolt casing 2, said bottom plate 3 having a bolt hole 10 for a bolt in the attachment foundation or in one concrete column. Moreover, the bolt casing comprises a top plate 4 forming the top of the bolt casing 2.

[0011] The side plate 5 comprises an opening 11 for installing a screwable nut to a bolt. The side plate 5 is trough-shaped. The profile of the side plate can be curved, U-shaped or V-shaped or polygonal. The opening angle α of the opening 11, i.e. the angle α between the sides 12 of the side plate directed from the opening 11 towards back part of the bolt casing 2 is about 60°. The opening angle α is less than 90°, typically 50°-70°. The column shoe 1 further comprises a top plate 4, which is attached to the side plate 5. The side plate 5 extends over the level determined by the top plate 4, i.e. in Fig. 1 above the top plate 4. The top plate 4 is arranged at a distance from the bottom plate 3, wherein there is a space for a bolt and a nut between the bottom plate 3 and the top plate 4. The bottom plate 3 and the top plate 4 can be attached to the side plate 5, e.g. by welding.

[0012] Column shoe 1 comprises at least one main bond means 6 for attaching the column shoe 1 and the concrete column to each other. There are two main bond means 6 in the embodiment according to figures. The main bond means 6 are vertical. The main bond means 6 are bar-shaped parts, e.g. deformed steel bars. The main bond means 6 are attached to the inner surface of the side plate 5, e.g. by welding. The main bond means 6 are attached to the part of the side plate 5 above the top plate 4. The lower ends of the main bond means 6 are bent towards the opening 11 in the side plate. Thus there is more space for welding of the main bond means 6. The bending point of the main bond means 6 is next to the side plate 5, typically at the level of the upper edge of the side plate 5. The main bond means 6 are disposed so that they are laterally outside of the area defined by the bolt hole 10 of the bottom plate 3.

[0013] Column shoe 1 further comprises a vertical back bond means 7 for attaching column shoe 1 to concrete column. The vertical back bond means 7 is a bar-shaped part, e.g. a deformed steel bar. The vertical back bond means 7 is vertical. The vertical back bond means 7 can be straight. The vertical back bond means 7 is arranged outside of the bolt casing 2 at a distance D from the bolt casing 2. The vertical back bond means 7 is typically placed at the horizontal symmetry axis 15 of the bolt casing 2. The vertical back bond means 7 extends vertically from the level of the lower edge of the side plate 5 to the level of the upper edge of the side plate 5, or slightly above it.

[0014] Moreover, column shoe 1 comprises at least one horizontal back bond means 8 attached to the outer surface of the side plate 5 at two points 9, e.g. by welding. The horizontal back bond means 8 is an elongated part, e.g. a deformed steel bar. The horizontal back bond means 8 is bent to a desired shape, e.g. to U-shape or V-shape. The part between the attachment points 9 of the horizontal back bond means 8 can be bent to an angle equal to the opening angle α of the opening 11 in the side plate 5. The horizontal back bond means 8 is attached horizontally to the side plate 5. The part of horizontal back bond means 8 between the attachment points 9 is totally or partly disjointed from the side plate 5, i.e. the part between the attachment points 9 is at a distance from the outer surface of the side plate 5. Thus the horizontal back bond means 8 forms a loop protruding from the side plate 5 inside of which the vertical back bond means 7 has been placed.

[0015] The vertical back bond means 7 is attached to the horizontal back bond means 8 between the attachment points 9 so that the vertical back bond means 7 is between the horizontal back bond means 8 and the outer surface of the side plate 5. The vertical back bond means 7 is at a distance D from the outer surface of the side plate 5. The length of the distance D is selected in each embodiment depending of the case, e.g. according to dimensions of column shoe 1. The distance D between the vertical back bond means 7 and the side plate 5 is typically at least 2 cm.

[0016] The vertical back bond means 7 is aimed to be placed as far as possible from the outer surface of the side plate 5 so that a joint as tight as possible between the column shoe and the concrete column is achieved. The horizontal back bond means and the vertical back bond means form a structure, which attaches the column shoe to concrete of the column against harmful horizontal eccentricity forces.

[0017] Column shoe 1 shown in the figures comprises two horizontal back bond means 8 as described above, of which one is attached to the lower part of the side plate 5 and the other to the upper part of the side plate 5. The vertical back bond means 7 is attached to both horizontal back bond means 8 as described above. There can be more than two horizontal back bond means 8, where necessary.

[0018] Column shoe 1 according to the invention can be implemented without vertical back bond means 7 so that the vertical back bond means 7 is placed between the part of the horizontal back bond means 8 between attachment points 9 and the side plate 5, e.g. when mounting the column shoe 1. The vertical back bond means 7 is attached to the horizontal back bond means 8, e.g. with a wire.

[0019] It is obvious to a person skilled in the art that the different embodiments of the invention are not solely restricted to the examples described above, and thus they can be varied within the scope of the following claims.

Claims

1. Column shoe (1) for attaching concrete columns to a foundation or to another concrete column, said column shoe (1) comprising

- a bolt casing (2) with an open side, said bolt casing (2) comprising a side plate (5) forming the side of the bolt casing (2), said side plate (5) comprising an opening (11) for installing a nut, a bottom plate (3) forming the bottom of the bolt casing (2), said bottom plate (3) comprising a bolt hole (10), and a top plate (4) forming the top of the bolt casing (2), and

- at least one main bond means (6) attached to the bolt casing (2) for attaching the column shoe (1) and the concrete column to each other, characterized in that

- the column shoe (1) further comprises at least one horizontal back bond means (8) attached to the outer surface of the side plate (5) at two points (9),

- the part of the horizontal back bond means (8) between the attachment points (9) is located at a distance from the side plate (5), and

- the column shoe (1) comprises a vertical back bond means (7) attached to the horizontal back bond means (8) between the attachment points (9), so that the vertical back bond means (7) is located between the horizontal back bond means (8) and the side plate (5).

2. Column shoe (1) according to claim 1, characterized in that the vertical back bond means (7) is located at a distance (D) from the side plate (5).

3. Column shoe (1) according to claim 2, characterized in that the distance (D) is at least 2 cm.

4. Column shoe (1) according to any of the preceding claims, characterized in that there are two horizontal back bond means (8), of which one horizontal back bond means (8) is attached to the lower part of the side plate (5) and the other horizontal back bond means (8) is attached to the upper part of the side plate (5).

5. Column shoe (1) according to any of the preceding claims, characterized in that the horizontal back bond means (8) is elongated and it is attached horizontally to the outer surface of the side plate (5).

6. Column shoe (1) according to any of the preceding claims, characterized in that the lower part of the main bond means (6) is attached to the inner surface of the side plate (5) above the top plate (4).

7. Column shoe (1) according to any of the preceding claims, characterized in that main bond means (6) comprises a bend (14) next to the side plate (5) of the column shoe, where the lower part of the main bond means (6) turns towards the opening (11) of the side plate.

8. Column shoe (1) according to any of the preceding claims, characterized in that an opening angle (α) of the opening (11) in the side of the bolt casing (2), i.e. the angle (α) between the sides (12) of the side plate directed from the opening (11) towards back part of the bolt casing (2), is less than 90°, typically 50°-70°.

9. Column shoe (1) according to claim 8, characterized in that the horizontal back bond means (8) is bent to an angle which is equal to the opening angle (α) of the opening (11) in the side plate (5).

Drawing