Column protection component and corrosion prevention structure for a metal column

Abstract

To prevent corrosion of columns by preventing accumulated dust from coming into contact with the columns.SOLUTION: A column protection component 10 for protecting an exposed root portion of a column 1 has a sloping face which covers an outer periphery of the root portion of the column 1 in top view and whose upper face moves downward as moving away from the column 1. The sloping face is composed of a roof-like structure having: a first plate material 10A which slopes downward as moving away from the column 1 in one radial direction of the column 1; and a second plate material 10B whose upper end is connected to an upper end of the first plate material 10A and which slopes downward as moving away from the column 1 in the other radial direction of the column 1. In the roof-like structure, an opening through which the column 1 passes is formed at a position including a part of a peak-like connection portion PL where the upper end of the first plate material 10A and the upper end of the second plate material 10B are connected.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a technique for protecting the root portion of an existing metal column and preventing corrosion at the root portion. The present invention is a technique particularly suitable for columns constituting a structure.

Background Art

[0002] A metal column stands upright from a foundation, for example, by having its lower part buried and fixed in concrete (foundation). Also, a metal column stands upright from a foundation, for example, by having its lower end fixed to the concrete (foundation) via a base plate. When such a column is placed in an environment where dust is likely to fly and accumulate, dust accumulates on the outer periphery of the root portion (foundation side) of the column. Furthermore, due to the water retention effect of the accumulated dust, the root portion of the column becomes a corrosive environment.

[0003] As a conventional technique for preventing corrosion of the root side portion of such a column, for example, corrosion prevention treatment is performed by painting the root portion side of the column, or by a cover or coating method. For example, Patent Document 1 describes using a highly corrosion-resistant material in parts where corrosion is likely to occur, such as near the embedded part. Also, Patent Document 1 describes providing a resin cover near the embedded part. Further, Patent Document 2 discloses performing circumferential reinforcement on a portion where corrosion has occurred in an existing steel pipe column and filling the gap with mortar.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the prior art, it is impossible to avoid the deterioration of caulking and the intrusion of moisture such as rainwater from the gap between the mortar and the steel pipe column. In addition, in a dust deposition environment, since dust has a water retention effect, the wetting time for the column surface increases at the dust deposition location. This promotes corrosion at the root of the column and there is a problem that a sufficient life extension effect may not be obtained.

[0006] Here, the method described in Patent Document 1 uses caulking or the like at the joint between the resin and the steel to prevent the intrusion of moisture. However, this method has a problem that moisture intrusion is a concern due to the aging deterioration of caulking or the like. In addition, this method has a problem that corrosion occurs at the upper part of the cover when the dust deposition height becomes high. Also, in the method of Patent Document 2, in a dust deposition environment, there is a concern about dust deposition on the upper part of the reinforcing material, and there is a possibility of corrosion caused by the dust deposited on the upper part of the reinforcing material.

[0007] The present invention focuses on the above points, and aims to prevent the deposited dust from contacting the column and prevent the corrosion of the column.

Means for Solving the Problems

[0008] The inventor of the present invention considered attaching an umbrella-shaped or gable roof-shaped column protection part that forms an inclined surface that slopes downward away from the column, that is, an inclined surface that moves away from the column downward, to the outer periphery of the root of the column. And thereby, it was considered to suppress the deposited dust around the column from contacting the surface of the column. Furthermore, considering the ease of manufacturing, the present invention was completed.

[0009] In order to solve the problem, one aspect of the present invention is a pillar protection part that protects the exposed base portion of an upright metal pillar, the pillar protection part covering the outer periphery of the base portion of the pillar when viewed from above, and having an upper surface with a slope that slopes downward as it moves away from the pillar, the slope being composed of a roof-like structure having a first plate material that slopes downward toward one radial direction of the pillar as it moves away from the pillar, and a second plate material that connects its upper end to the upper end of the first plate material and slopes downward toward the opposite radial direction of the pillar as it moves away from the pillar, and the roof-like structure has an opening through which the pillar passes, formed at a position that includes a part of a ridge-shaped connecting portion that connects the upper end of the first plate material and the upper end of the second plate material. [Effects of the Invention]

[0010] According to this aspect of the present invention, even if dust flies and accumulates at the base of the pillar, the dust is prevented from coming into contact with the pillar, thereby preventing corrosion at the base of the pillar. Furthermore, the dust that has landed on the pillar protection component falls along its inclined surface and accumulates in a position away from the pillar. Furthermore, according to one aspect of the present invention, it is possible to prevent not only dust but also water such as rainwater from accumulating, which also has the effect of preventing corrosion. Furthermore, by constructing the column protection component from flat plate material, it is possible to easily manufacture the column protection component. [Brief explanation of the drawings]

[0011] [Figure 1] 1A and 1B are diagrams illustrating a pole protection component according to an embodiment of the present invention, in which (a) is a top view, (b) is a side view seen from the extension direction of the ridge, and (c) is a side view seen from the first plate side. [Figure 2] 10A and 10B are diagrams showing an example of joining first and second plate materials to a base plate. [Figure 3] 10A and 10B are diagrams illustrating an example of joining a side surface member and a base plate. [Figure 4]It is a diagram for explaining column protection components for columns according to examples of other embodiments. (a) is a top view. (b) is a side view seen from the extending direction of the peak. (c) is a side view seen from the first plate material side.

Mode for Carrying Out the Invention

[0012] Next, embodiments of the present invention will be described with reference to the drawings. The column protection component of the present embodiment aims to protect, for example, the root part of a column exposed from the foundation in a metal column erected from the foundation. In the present embodiment, as an example of a metal column, a case where it is a metal column made of a steel pipe or the like erected from a foundation such as concrete as shown in FIG. 1 will be described.

[0013] (Regarding the erection of the column) The lower end portion of column 1 is fixed to the foundation concrete, so that column 1 is erected from foundation 2. Note that foundation 2 is not limited to a concrete foundation. Foundation 2 serves as a support base for supporting column 1. The fixing of column 1 to foundation 2 is performed, for example, by embedding the lower part of column 1 in foundation 2. In this case, for example, an anchor member is provided at the lower end portion of column 1, and the anchor member is fixed to the foundation concrete.

[0014] In the present embodiment, as shown in FIG. 1, a base plate 3 as an anchor member is fixed to the lower end surface of column 1 by welding. Taking the case where column 1 is fixed to foundation 2 by fixing the base plate 3 to foundation 2 with anchor bolts 4 as an example for explanation. As an anchor member, another anchor member (not shown) may be provided at the lower end portion of column 1, and the base plate 3 may be provided on column 1 in an outward flange shape in the middle part of the lower part of column 1.

[0015] (Column protection component 10) When attached to the pillar 1, the pillar protection part 10 is a part that covers the outer periphery of the base of the pillar 1 when viewed from above, and has an upper surface that slopes downward as it moves away from the pillar 1. The pillar protection component 10 of this embodiment comprises a first plate material 10A and a second plate material 10B, and when the upper ends of the first plate material 10A and the second plate material 10B are assembled together, a roof-like structure with an external appearance similar to a gable roof is formed, as shown in Figure 1.

[0016] The first plate material 10A is a rectangular, flat member that slopes downward as it moves away from the pillar 1 in one radial direction (toward the right in FIG. 1(a)). The second plate material 10B is a rectangular, flat member whose upper end is connected to the upper end of the first plate material 10A and which slopes downward as it moves away from the column 1, facing the opposite side of the one radial direction of the column 1 (toward the left in Figure 1(a)). In this specification, the radial direction is not limited to the diameter direction when the cross section of the pillar is circular, but is understood to mean the direction across the cross section when the cross section of the pillar is elliptical or polygonal. The radial direction refers to, for example, the direction perpendicular to the vertical axis (extension direction) of the pillar 1.

[0017] However, in the roof-like structure comprising the first plate 10A and the second plate 10B, an opening constituting a penetration portion 10D through which the pillar 1 penetrates is formed at a position including a part of the ridge-like connecting portion PL where the upper end of the first plate 10A and the upper end of the second plate 10B are connected. The opening has the same or almost the same shape as the outer diameter contour of the pillar 1 in top view. The roof-like structure also includes a side member 10C that closes the opening on the side formed by the first plate material 10A and the second plate material 10B at the end of the connecting portion PL in the extension direction. The side member 10C is made of, for example, a triangular plate material (see FIG. 1(B)). There are no particular limitations on the shape of the side member 10C, as long as its outer surface is wall-like and extends vertically. It is preferable that the side member 10C be provided at each opening on both end sides of the connecting portion PL in the extension direction.

[0018] That is, the roof-shaped structure has a virtual line passing through the column 1 horizontally as its peak (ridge line), and at the peak position, the upper edges (upper end portions) of the first plate member 10A and the second plate member 10B are connected to each other. Then, the first plate member 10A and the second plate member 10B are each arranged with a gradient in two directions from the peak position, and form a triangle when viewed from the extending direction of the peak. And the space of the triangle is blocked by the side member 10C. The side member 10C corresponds to the gable wall in the gable roof. And an opening of the through portion 10D capable of passing through the column 1 is formed at a position passing through the peak (connection portion PL). It is preferable that the peak position passes through the center of the column 1, but it may be eccentric from the center of the column 1.

[0019] Also, although it is preferable that the through portion 10D is formed at the central portion in the extending direction of the peak, it may be shifted to the left or right. In order to prevent dust and moisture from entering the root portion of the column 1 from the gap between the opening and the column in a state where the column 1 penetrates the opening of the through portion 10D, it is preferable that the opening of the through portion 10D and the column 1 are joined. As the joining method, welding is desirable from the viewpoints of workability and durability of the joint portion. In addition, instead of welding, it may be closed by a treatment such as filling the gap with a caulking agent.

[0020] As shown in FIG. 1(b), the inclination angle (gradient) θ of the first plate member 10A and the second plate member 10B is a depression angle from the horizontal direction, for example, 30 degrees or more, preferably 60 degrees or more. Also, there is no particular upper limit for the inclination angle. For example, the upper limit is set to 80 degrees. Note that the inclination angle of the first plate member 10A and the inclination angle of the second plate member 10B may be the same or different. When the column protection component 10 of the present embodiment is assembled to the shape of the roof-shaped structure, the lower end surfaces of the first plate member 10A, the second plate member 10B, and the left and right side members 10C are designed to be flush, for example.

[0021] The roof-like structure constituting the column protection component 10 of this embodiment is large enough, when viewed from above, to completely cover the base plate 3. The column protection component 10 of this embodiment has a rectangular shape similar or approximately similar to that of the base plate 3, when viewed from above. Here, in order to strengthen the connection between the pillar 1 and the base plate 3, a rib may be provided to connect the pillar 1 and the base plate 3, as shown in Fig. 4. The rib is placed inside the base plate 3 when viewed from above, and the inclination angle is set so that the rib is placed inside the space formed by the roof-like structure. In this embodiment, the pole protection component 10 is made of a metal plate such as a steel plate or an aluminum alloy plate.

[0022] Next, an embodiment of the joining of the pole protection component 10 to the pole 1 and the base plate 3 will be described with reference to the drawings. In the pole protection component 10 of this embodiment, the pole 1 is positioned in the penetration portion 10D, and the upper edge of the first plate 10A and the upper edge of the second plate 10B are joined by fillet welding to form a connecting portion PL, as shown in Fig. 1. Then, the inner surface of the lower edge portion of the first plate 10A and the inner surface of the lower edge portion of the second plate 10B are joined by fillet welding to the upper edge of the outer end surface of the base plate 3, as shown in Fig. 2. Reference numeral 11 denotes an example of a welded portion.

[0023] The base plate 3 has a rectangular shape, and the first plate material 10A and the second plate material 10B are arranged so that the opposing directions of the first plate material 10A and the second plate material 10B are aligned with the direction of the two opposing sides of the base plate 3. Furthermore, the dimensions and inclination angles of the first plate material 10A and the second plate material 10B are designed in advance so that the inner surfaces of the lower sides of the first plate material 10A and the second plate material 10B can contact the two opposing sides of the base plate 3, respectively.

[0024] Furthermore, the upper end portion of each side member 10C is joined to the lower surface of the first plate material 10A and the second plate material 10B by fillet welding, and the lower surface of each side member 10C is joined to the outer end surface of the base plate 3 by fillet welding, as shown in Figure 3. In this way, the column protection component 10 is assembled and attached to the base of the column 1. The column protection component 10 is joined to the surface of the column 1 at the penetration portion 10D position by fillet welding all around the circumference.

[0025] (Actions, effects, etc.) This allows the column protection component 10 to form an enclosed space around the outer periphery of the base of the column 1. That is, with the above configuration, in this embodiment, even if a situation arises in which dust flies into the base of the column 1 and is likely to accumulate, the accumulated dust is prevented from coming into contact with the surface of the column 1 or from remaining in contact therewith, thereby preventing corrosion at the base of the column 1. Note that dust that has landed on the upper surface of the first plate material 10A or the second plate material 10B of the column protection component 10 falls along the inclined surface of the upper surface and accumulates in a position away from the column 1. Furthermore, according to this embodiment, it is possible to prevent not only dust but also water such as rainwater from accumulating, which also has the effect of preventing corrosion.

[0026] (Variation) (1) In Fig. 4, a joint extending in the vertical direction is formed at the lower end of the first plate material 10A and the second plate material 10B. This allows the first plate material 10A and the second plate material 10B to be joined by fillet welding in a state where the surfaces of the first plate material 10A and the second plate material 10B are in contact with the outer end surface of the base plate 3, thereby improving, for example, the joint strength. (2) In the above description, the pole protection component 10 is made of metal, but the pole protection component 10 may be made of resin such as carbon fiber. In this case, for example, the resin is melted and welded. (3) In the above explanation, the case where the lower end of the column protection component 10 is joined to the base plate 3 is exemplified, but the lower end of the column protection component 10 may also be joined to the part of the foundation 2 on the outer periphery of the base plate 3. In addition, a sealed space may be formed inside the column protection component 10.

[0027] (others) The present disclosure may also have the following configuration. (1) A pillar protection component for protecting the exposed base of an erected metal pillar, Cover the outer periphery of the root part of the column from above, and the upper surface has an inclined surface that slopes downward as it moves away from the column. The inclined surface is composed of a first plate member that inclines downward as it moves away from the column, towards one side in the radial direction of the column. A second plate member is connected to the upper end of the first plate member at the upper end, and inclines downward as it moves away from the column, towards the side opposite to the one side in the radial direction of the column. It is composed of a roof-shaped structure having An opening through which the column penetrates is formed at a position including a part of the peak-shaped connecting portion where the upper end of the first plate member and the upper end of the second plate member are connected. Column protection part, characterized in that. (2) The roof-shaped structure is provided with side members that close the openings on the side surfaces formed by the first plate member and the second plate member at both ends in the extending direction of the connecting portion. Column protection part according to (1), characterized in that. (3) A column protection part for a metal column that is fixed to a foundation via a base plate and stands upright. The roof-shaped structure is sized to completely cover the base plate in a top view. Column protection part according to (1) or (2), characterized in that. (4) A corrosion prevention structure for a metal column, which attaches the column protection part according to any one of (1) to (3) to the root part of a metal column to prevent dust from accumulating on the root part of the column. (5) With the column penetrating through the penetrating opening, the opening and the column are joined by welding. Corrosion prevention structure for a metal column according to (4), characterized in that.

Explanation of symbols

[0028] 1 Column 2 Foundation 3 Base plate 4 Anchor bolt 10 Column protection part 10A First plate member 10B 2nd plate 10C side member 10D through section PL junction (peak) θ tilt angle

Claims

A column protection part for protecting the base part of a metal column erected from a foundation, a first plate having an inclined surface inclined downward as it moves away from the column, facing one direction in the radial direction of the column, a second plate forming an inclined surface inclined downward as it moves away from the column, facing the side opposite to the one direction in the radial direction of the column, and is composed of a roof-shaped structure having, at the upper end of the inclined surface of the first plate and at the upper end of the inclined surface of the second plate, there are openings that go downward as they move away from the column, respectively. The upper end of the first plate and the upper end of the second plate are connected to each other, and the virtual line of the ridge line formed by the connection constitutes a peak-shaped connection part that penetrates the column in the lateral direction, and one opening through which the column penetrates is formed by the opening of the first plate and the opening of the second plate, The column protection part is characterized by this. According to claim 2, the column has a circular or elliptical cross-section, and the openings of the first plate and the second plate are each in a semi-elliptical shape that converges as they move away from the column, which is characterized by this. The column protection part described in claim 1.

3. The roof-shaped structure includes side members that close the openings on the sides formed by the first plate and the second plate at both ends in the extending direction of the connecting part. The column protection part described in claim 1 is characterized by this. A corrosion prevention structure for a metal column fixed and erected via a base plate to a foundation, comprising the column protection part described in any one of claims 1 to 3, attached to the base part of the metal column, and the upper end of the first plate and the upper end of the second plate are joined by welding, in a state where the column penetrates through the opening through which the column penetrates, at the position of the opening, the column protection part and the column are joined by welding, and furthermore, the lower ends of the first plate and the second plate and the base plate are joined by welding. A corrosion prevention structure for a metal column.

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