KR101371197B1 - Production process of the hybrid lightweight steel structure according to the stress variation - Google Patents

Abstract

The present invention relates to a lightweight steel structure used for a roof frame of a factory or a warehouse, a frame supporting frame for finishing a building, and the like, in which the thickness of each component is changed in response to the type and size of stress. Welding each steel plate in the longitudinal direction while unwinding two or more steel coils to produce one forming steel sheet in which each steel sheet is integrated, and forming a lightweight steel structure by roll forming the forming steel sheet. Forming a furnace, cutting the processed lightweight steel structure to a predetermined length, wherein the bending portion formed by the roll forming, the predetermined distance is separated from the weld formed by the welding It features.

Description

Production process of the Hybrid lightweight steel structure according to the stress variation}

The present invention relates to a lightweight steel structure used for a roof frame of a factory, a warehouse, etc., a frame supporting frame for finishing a building, and more specifically, the thickness of each component is changed in response to the type and size of stress. The present invention relates to a method for manufacturing a hybrid lightweight steel structure.

Since there are no heavy loads on the roof frame of factories or warehouses, or the frame to support the exterior materials of buildings, there are many lightweight steel structures such as C-type and Z-type, which are formed of metal plates thinner than the steel formed by rolling. It is used. Such lightweight steel structures are generally machined by milling, welding and forming.

In case of milling in the above-mentioned processing methods, it is necessary to cut with a cutter to match the shape of the cross section. Therefore, production specifications and shapes cannot be varied.In case of welding, jig facilities, processing costs according to welding work and While there is a problem that it is uneconomical due to labor costs, in the case of forming by the forming process is a continuous process, it can be produced in a variety of specifications can be said to be a more economical processing method than the above milling or welding.

Therefore, lightweight steel structures such as C-type and Z-type are usually processed by roll forming. That is, the steel sheet manufactured in a steel mill and wound in a coil shape is conveyed by a feed roller while the coil is unwinded, and then the steel sheet is formed into a required shape by passing through the forming roller 1 shown in FIG. This is cut to the required length to complete the lightweight steel structure 2.

By the way, since the coil-shaped steel sheet is always made of the same thickness, as described above, the lightweight steel structure produced by roll forming, as shown in Figure 1 (b), all components, such as flanges, webs, etc. are the same It has been taken for granted that it is made of thickness.

On the other hand, the stress generated on the flange, the web, etc. of the light steel structure by the load acting on the light steel structures, depending on the location of the use of the light steel structure and the manner of structural coupling, respectively.

For example, when a lightweight steel structure is used as a horizontal member such as a roof member, when both ends of the horizontal member are strongly coupled to a member such as a pillar, a large parent moment and a large shear force act on both ends, and In this case, only a large positive moment acts and a shear force is hardly applied. However, when both ends of the horizontal member are pin-coupled to a member such as a pillar, only a large shear force acts on both ends but a bending moment does not work. Only large moments act, but shear forces rarely work.

On the other hand, the flange corresponds to the bending stress acting on the member, and the web corresponds to the shear stress. Therefore, it can be said that it is the most economical in terms of material cost to manufacture a lightweight steel structure so as to vary the thickness of each component in response to each of the stresses.

 However, as described above, in general, lightweight steel structures have flanges and webs formed of the same thickness by one steel plate, and thus, the specification of the member is determined based on the deflection and bending stress values based on the maximum bending moment. By doing so, the thickness of the web where the shear stress is hardly generated can be made the same as the thickness of the flange, and tolerate the problem of excessive use of steel.

In order to improve this problem, some suggest the method of varying the thickness of flange and web by attaching reinforcement plate to flange, but the attachment of the flange and reinforcement plate, which is the base material, increases the number of spot welding, resulting in long construction period. However, there is a problem that the precision of the welding construction is inferior, and only two edge portions of the reinforcement plate are welded, thereby causing structural defects because the two members are not completely integrated.

As another method, a method of cutting the flanges and the webs into steel sheets having different thicknesses and then welding them to form a lightweight steel structure having a required shape may be proposed. It is difficult to economically produce various specifications in a small amount because it is necessary to install a jig suitable for each standard, and the welding construction needs to be welded at a necessary angle according to the shape of the light steel structure to be manufactured, so there is a high possibility of defects in welding construction. In addition, the location where the flange and the web meet is a site where the cross section is rapidly changed, so even though it is easy to generate stress concentration, it overlaps with the welded part. There is a problem in forming.

The present invention has been proposed in order to solve the above problems in the prior art, the hybrid lightweight to remove the structural weakness while each component member such as flange and web to have a different thickness corresponding to the stress type and size, etc. The purpose is to provide a method for economically manufacturing the steel structure by roll forming.

According to a preferred embodiment of the present invention for the above problems, iii) calculating the design load acting on each part of the lightweight steel structure by structural calculation, ii) varying the thickness according to the calculated design load Cutting the steel sheet for each constituent member to a predetermined length and width, i) welding each cut steel sheet to produce a single forming steel sheet, i) rolling forming the steel sheet for molding, and It comprises a step of forming into a lightweight steel structure having a shape of, the bending portion formed by the roll forming of the step iii), the predetermined distance is separated from the weld formed by the welding of the iii) step Provided is a method of manufacturing a hybrid lightweight steel structure.

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According to another preferred embodiment of the present invention, iii) welding each steel sheet in the longitudinal direction while releasing two or more steel sheet coils having different thicknesses, to produce one forming steel sheet in which each steel sheet is integrated; Ii) roll forming the forming steel sheet to form a lightweight steel structure having a predetermined shape; and iii) cutting the processed light steel structure to a predetermined length, wherein the step of step ii) is performed. The bending part formed by roll forming is provided with the manufacturing method of the hybrid lightweight steel structure characterized in that a predetermined distance is separated from the welding part formed by the welding of said step iii).

Each manufacturing method of the light steel structure may further include forming an uneven portion on one surface of the light steel structure.

In the lightweight steel structure in which the horizontal member flange and the vertical member web are continuously formed by one steel plate according to the manufacturing method, the thickness of each cross section of the flange and the web has a different value as a whole. At least one of the inner ends of the flanges contacted is configured equal to the cross-sectional thickness of the web for a predetermined length, or at least one of the outer ends of the webs contacted the flange is configured equal to the cross-sectional thickness of the flange with respect to the predetermined length. Hybrid lightweight steel structure is characterized in that it is produced.

In this case, the web has an uneven portion formed at an intermediate portion in the vertical direction, and a flat portion is formed at both upper and lower ends thereof, and the uneven portion has a shape in which the concave portion and the convex portion and the central axis portion between the concave portion and the convex portion are continuous. Can be.

Hybrid lightweight steel fittings produced by the present invention can significantly reduce the amount of steel used by varying the thickness of the constituent members forming the lightweight steel structure according to the type and size of the stress, it is produced by roll forming uniform It is possible to ensure a stable and stable quality, it is possible to expect the effect that the stress concentration phenomenon does not occur in any one place by making the bending portion and the weld portion do not match.

1 is a perspective view of a state of roll forming a lightweight steel structure according to the prior art and a cross-sectional view of the lightweight steel structure manufactured accordingly.
2 is a cross-sectional view showing various embodiments of a hybrid lightweight steel structure manufactured by the present invention.
3 is a cross-sectional view showing an embodiment of the hybrid lightweight steel structure of the present invention having another shape.
4A and 4B are explanatory views illustrating a cross section of the light steel structure of the present invention designed to correspond to the stress and the corresponding structure according to the fixed structure of the light steel structure.
5 is a perspective view of another embodiment of the hybrid lightweight steel structure of the present invention in which an uneven portion is formed in a part of a constituent member.
6 is an explanatory diagram showing a manufacturing process of the hybrid lightweight steel structure according to the first embodiment of the present invention.
7 is an explanatory diagram showing a manufacturing process of a hybrid lightweight steel structure according to a second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, however, it is to be understood that the present invention is not limited to the disclosed embodiments.

2 illustrates various embodiments of a hybrid lightweight steel structure 100 fabricated by the present invention. According to FIG. 2, in the lightweight steel structure 100 of the present invention, the flange 111, which is a horizontal member, and the web 112, which is a vertical member, are continuously formed by one steel plate, and the flange 111 and the web are continuously formed. Each cross-sectional thickness of 112 is formed to have a different value as a whole as one of the technical features. These technical features not only promote manufacturing efficiency, but also reduce the amount of steel used, enabling an economically optimal cross-sectional configuration.

'형상처럼 어느 한 구성부재의 중간부분이 다른 구성부재의 단부와 연결되는 경우는 '하나의 강판에 의해 연속적으로 성형'된 것이 아니라고 할 것이다.Here, the 'continuously formed by one steel plate', as shown in Figures 2 and 3, each of the structural members 110, lightweight and steel structures, such as flanges and webs forming the lightweight steel structure 100 Detailed configuration for forming a (to be referred to below. For example,

'If the middle portion of one component member is connected to the end of the other member like a shape, it will be said that it is not' continuously formed by one steel plate '.

As such, the lightweight steel structure 100 according to the present invention is based on different thicknesses of the flange 111 and the web 112, but the inner and outer ends of the flange 111 in contact with the web 112. At least one of the web 112 is configured equal to the cross-sectional thickness of the web 112 with respect to a predetermined length, or at least one of the inner and outer ends of the web 112 contacting the flange 111 has a flange ( It is another technical feature of the present invention to be configured in the same manner as the cross-sectional thickness of 111). This technical feature not only facilitates the fabrication of the light weight steel structure 100, but also disperses the weak part that is inevitably generated due to the cross-sectional change, thereby preventing the concentration of stress in any one of the light weight steel structure 100 It has the effect of increasing the overall rigidity.

For reference, in describing the configuration of the present invention and describing the claims, the term 'predetermined', such as 'predetermined length', 'predetermined shape', etc., is used, which is not particularly limited in length or shape. As this is inevitably used, it does not cause any problem in specifying the content or scope of the invention, and thus the term should not be regarded as an ambiguity.

(A) and (b) of FIG. 2 constitute both the inner end portions 111 'of the flange 111 in the same manner as the cross-sectional thickness of the web 112 by a predetermined length, and (c) and (d) Is constituted in the same manner as the cross-sectional thickness of the web 112 only by a predetermined length with respect to any one of the inner end portions 111 'of the flange 111. On the contrary, FIGS. 2E and 2F have the same length as the cross-sectional thickness of the flange 111 with respect to any one of the outer ends 112 'of the web 112, and (g) And (h) constitute both the outer end 112 'of the web 112 in the same manner as the cross-sectional thickness of the flange 111 by a predetermined length.

In addition, (a) and (h) of FIG. 2 comprise the cross-sectional thickness of the flange 111 thicker than that of the web 112, and (b) and (g) flange the cross-sectional thickness of the web 112. And (c) to (f), the flange 111 of which is one of the thicker than that of (111) or together with the cross-sectional thickness of the web 112 to form a thicker than that of the other components A modification is shown.

As described above, by varying the cross-sectional thickness of each component member 110 forming the light weight steel structure 100 according to the present invention to stabilize the load acting on the light weight steel structure 100 with a small amount of steel It has the economic effect of being very supportive. This will be described in more detail.

4A and 4B illustrate a stress diagram according to a fixed structure of the light weight steel structure 100 and a cross section of the light weight steel structure 100 of the present invention designed to correspond thereto. For easy understanding of the description, the following example assumes that the lightweight steel structure 100 is used as a horizontal member such as beams, and the load acting on it is equally distributed.

First, FIG. 4A assumes a case in which both ends of the lightweight steel structure 100 are hinged. In this case, the maximum bending moment (static moment) occurs at the center portion, and the bending moment does not occur at both ends. On the contrary, the shear stress is zero at the center but the maximum shear stress is generated at both ends.

Therefore, since both ends of the lightweight steel structure 100 need to be reinforced against shear stress, the cross-sectional thickness of the web 112 corresponding to the vertical member needs to be thicker than the center portion, and the center portion needs to be reinforced against bending stress. Therefore, the cross section thickness of the flange 111, which is a horizontal member, is thicker than both ends, and since the maximum bending moment is a constant moment, the cross section thickness of the lower flange 111 is particularly effective for reinforcement. have. However, in the above embodiment, the outer end portion 112 ′ of the web 112 at both ends is exemplified by the same configuration as the end face thickness of the flange 111 having a thin cross section thickness, but FIG. As shown in FIG. 2, the inner end 111 ′ of the flange 111 may be formed in the same configuration as that of the web 112 having a thick cross-sectional thickness. In this case, the amount of steel used is somewhat increased, but the resistance to shear buckling is increased. Therefore, the selection of a specific cross-sectional shape should be determined by examining the size of the load and the specification of the lightweight steel structure 100. Similarly, in the above embodiment, when the lower flange 111 of the central portion is thickly formed, the outer flange portion 112 'of the web 112 is formed to have the same thickness as the cross-sectional thickness of the flange 111 having a thicker cross-sectional thickness by a predetermined length. However, this also can be formed in the same configuration as the cross-sectional thickness of the web 112, the inner end portion 111 'of the flange 111, as shown in Figure 2 (c).

4b assumes that both ends of the lightweight steel structure 100 are strongly coupled. In this case, a constant moment is generated at the center portion, and a parent moment is generated at both ends. At both ends, as shown in FIG. 4A, the maximum shear stress is generated.

Therefore, since the reinforcement for the upper flange 111 and the web 112 is required at both ends of the lightweight steel structure 100, the cross-sectional thickness of the upper flange 111 and the web 112 is lower flange 111 Compared with the lower flange 111, the thickness is formed thicker than the lower flange 111. Therefore, the thickness of the lower flange 111 may be the most efficient cross-sectional configuration. Since the cross-sectional thickness of the outer end 112 'of the web 112 or the inner end 111' of the flange 111 is the same as described above with reference to FIG. 4A, a description thereof will be omitted.

As such, an economical cross-sectional design is possible by varying the cross-sectional thickness according to the type or size of stress acting on each of the component members 110 of the light-weight steel structure 100, but on the other hand, at least one component member 110 By forming the concave-convex portion 120 in the c), it is possible to provide a structurally stable lightweight steel structure 100 without increasing the cross-sectional thickness of the component 110. For example, the uneven portion 120 may be a continuous waveform formed on the web 112, as shown in each embodiment of Figure 5, the uneven portion 120 in the middle of the vertical direction of the web 112 The concave-convex portion 120 may be formed in a shape in which the concave portion 121 and the convex portion 122 and the central axis portion 123 between the concave portion 121 and the convex portion 122 are continuous. The concave-convex portion 120 formed of the concave portion 121, the convex portion 122, and the central axis portion 123 may be formed in the entire upper and lower lengths of the web 112, but as mentioned above, the web 112 may be formed. It is preferable that the uneven portion 120 is formed at an intermediate portion in the up and down direction, and the flat portion 124 is formed at both upper and lower ends so that the accordion effect is suppressed by the flat portion 124. Here, the accordion effect refers to a corrugated plate in which the cross section of the plate is formed in a shape in which the corrugation is repeated for the entire width of the plate, that is, the plate is formed in the shape of an accordion. In this case, it refers to a phenomenon in which the plate hardly resists this force and is deformed due to tension or compression.

4A and 4B, the cross-sectional shape of the lightweight steel structure 100 applied thereto is different from the center and both ends. However, when the stress change is not so large, the flange 111 and the web ( All of the lightweight steel structures 100 may be formed in the same cross section with only the difference with respect to the cross-sectional thickness of 112. For example, the web 112 has a thin cross-sectional thickness with respect to the entire length based on only the bending stress and the deflection value as in the conventional member selection method, and the flange 111 subjected to the bending load has a thick cross-sectional thickness with respect to the entire length. It is to have.

In such a case, the amount of steel used may be increased rather than varying the shape of the cross section at each position in the longitudinal direction, but the manufacturing process may be reduced, and thus economical production may be possible.

In addition, the above embodiments have been described using the C-type lightweight steel structure 100 as an example, but the same applies to the lightweight steel structure 100 having a shape as shown in (a) and (b) of FIG. 3. It will be apparent that the repeated description thereof will be omitted.

So far, the structural shape of the hybrid lightweight steel structure 100 according to the present invention has been described. Hereinafter, the method of manufacturing the hybrid lightweight steel structure 100 will be described.

6 conceptually illustrates a method for manufacturing the light weight steel structure 100 according to the first embodiment of the present invention. The method for manufacturing the light weight steel structure 100 according to the first embodiment includes: Performing structural calculation to set the cross-sectional thickness of (110), ii) cutting the steel plate (131) for the constituent member (110), (i) manufacturing the forming steel plate (130), i) roll Forming the lightweight steel structure 100 by forming.

Iii) performing structural calculation to set the cross-sectional thickness of the component member 110;

First, the design load acting on each part of the lightweight steel structure 100 is calculated by structural calculation. The position of the lightweight steel structure 100 and the type and size of the load acting on each component member 110 such as the web 112 and the flange 111 by the design load will vary depending on the fixing structure at both ends. As described above.

Ii) cutting the steel sheet 131 for the component member 110

Cutting the steel plate 131 for each component member 110 having a different cross-sectional thickness according to the calculated design load to a predetermined length and width. FIG. 6A illustrates a shape in which the steel sheets 131 of the respective structural members 110 are cut for the lightweight steel structure 100 to be manufactured. In FIG. 6 (a), the center portion cuts each of the thin steel sheet 131 'for the web, the thick steel sheet 131 "for the flange, and both ends the thick steel sheet 132" for the web. Each thin steel plate 131 'is cut for a flange.

At this time, while the width of the steel sheet for the web is slightly larger than the width of the web, instead the width of the flange 111 is slightly smaller, or the width of the steel sheet for the flange is slightly larger than the width of the flange 111, instead of the width of the steel sheet for the web By somewhat smaller, the weld 141 and the bend 142 generated by the following steps should not overlap at the same position.

Iii) preparing the forming steel sheet 130

Each cut steel plate 131 is welded to form a single forming steel sheet 130. 6 (b) shows a state in which the forming steel sheet 130 is manufactured through a welding process.

Iii) forming the lightweight steel structure 100 by roll forming

Finally, the forming steel sheet 130 is roll-formed to form a lightweight steel structure 100 having a predetermined shape. 6 (c) shows how such a roll forming operation is performed. This completes the hybrid lightweight steel structure 100 of the present invention.

On the other hand, the hybrid lightweight steel structure 100 of the present invention can be reinforced by forming the uneven portion 120 in at least one component member 110 as described above. To this end, the first embodiment may further include a step of forming the uneven portion 120. The method of forming the concave-convex portion 120 may be not only by roll forming, but also by pressing. In the case of roll forming, it is advantageous in that it does not require a separate process, but it is impossible to form the uneven parts 120 of various shapes.In contrast, in the case of pressing, an additional process called a pressing process is required, but only a mold is replaced. It is advantageous in that it can form the uneven portion 120 of various standards and shapes. Therefore, the concave-convex portion 120 of the continuous wave form is preferably a roll forming method, and the concave-convex portion 120 formed of the concave portion 121, the convex portion 122 and the central shaft portion 123 is a press method. It can be said that it is preferable.

Therefore, the step of forming the uneven portion 120 is performed at the same time as the roll forming operation of step iii) or the subsequent process after completing the forming of the light weight steel structure 100 by the step iii).

7 conceptually illustrates a manufacturing method of the light-weight steel structure 100 according to the second embodiment of the present invention. The manufacturing method of the light-weight steel structure 100 according to the second embodiment is iii) for molding. Manufacturing the steel plate 130, ii) forming the lightweight steel structure 100 by roll forming, and iii) cutting the molded lightweight steel structure 100 to a predetermined length.

Iii) preparing the forming steel sheet 130

It is a step of preparing a forming steel sheet 130 for roll forming to be described later. The forming steel sheet 130 should be formed to vary the cross-sectional thickness according to the component member (110). The forming steel sheet 130 is manufactured by welding each steel sheet 131 in the longitudinal direction while releasing two or more steel sheet coils having different thicknesses, whereby each steel sheet 131 is integrated into one roll for forming. The forming steel plate 130 is prepared.

Ii) forming the lightweight steel structure 100 by roll forming

Roll forming the forming steel sheet 130 to form a lightweight steel structure 100 having a predetermined shape. Through the roll forming, the forming steel sheet 130 is formed with a bending portion 142 for the shape. The bending part 142 should be spaced a predetermined distance from the welding part 141 in the step iii). This spacing is to prevent the concentration of stress in any one place to increase the structural stability of the lightweight steel structure 100 as described above.

Iii) cutting the molded lightweight steel structure 100 to a predetermined length

By cutting the processed light steel structure 100 to a predetermined length, the production of the light steel structure 100 of the present invention is completed.

Also in the second embodiment, the step of forming the uneven portion 120 in at least one component member 110 of the lightweight steel structure 100, the step of forming the uneven portion 120, Simultaneously with the roll forming operation of step ii) or the subsequent process after completing the forming operation of the light-weight steel structure 100 according to step ii), or the subsequent process after the cutting operation by step iii) is completed. .

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the invention is not limited to the disclosed embodiments, but, on the contrary, It is obvious that it will be possible to carry out various modifications thereof. It is therefore intended that such modifications are within the scope of the invention as set forth in the claims.

100: hybrid lightweight steel structure 110: component
111: flange 111 ': inner end
112: web 112 ': outer end
120: uneven portion 121: recessed portion
122: convex portion 123: central axis portion
124: flat portion 130: forming steel sheet
131: steel sheet 131 ': thin steel sheet
131 ": thick steel plate 141: welded portion
142: bending part

Claims (6)

delete delete In manufacturing lightweight steel structures,
(B) calculating the design load acting on each part of the lightweight steel structure by structural calculation;
(B) cutting the steel sheet for each component having a different cross-sectional thickness in accordance with the calculated design load to a predetermined length and width;
(B) welding each cut steel plate to produce a single forming steel sheet;
⒟ forming a lightweight steel structure having a predetermined shape by roll forming the forming steel sheet;
The bending part formed by the roll forming of the thinning step is a method for manufacturing a hybrid lightweight steel structure, characterized in that a predetermined distance is separated from the welding portion formed by the welding in the thinning step. 4. The method of claim 3, further comprising the step of forming an uneven portion in at least one of the constituent members, wherein the step of forming the uneven portion is performed simultaneously with the roll forming operation of the step (d) or by the step (d). Hybrid light steel structure manufacturing method characterized in that the process proceeds to the subsequent process after completing the forming of the light steel structure In manufacturing lightweight steel structures,
(B) welding each steel sheet in a lengthwise direction while unwinding two or more steel sheets having different thicknesses, thereby producing one forming steel sheet in which the steel sheets are integrated;
Roll forming the steel sheet for forming to form a lightweight steel structure having a predetermined shape;
⒞ cutting the processed light steel structure to a predetermined length;
The bending part formed by the roll forming of the thinning step is a method for manufacturing a hybrid lightweight steel structure, characterized in that a predetermined distance is separated from the welding portion formed by the welding in the thinning step. The method of claim 5, further comprising the step of forming an uneven portion in at least one of the constituent members, wherein the step of forming the uneven portion at the same time as the roll forming operation of the step 또는, or the lightweight steel structure by the ⒝ step Method for producing a hybrid lightweight steel structure, characterized in that proceeds to the subsequent process after the completion of the molding operation, or to the subsequent process after the cutting operation by the ⒞ step is completed

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