Maximum bending moment analysis method and maximum bending moment analysis program

Abstract

To provide an analysis method of maximum bending moment for quantitatively and integrally evaluating the maximum bending moment of an H-shaped steel.SOLUTION: An analysis method of maximum bending moment for evaluating the maximum bending moment of an H-shaped steel 10 on which a bending moment acts evaluates the maximum bending moment that the H-shaped steel 10 can achieve based on a calculated value Mcal of the maximum bearing force determined from the following formula (1): [Numerical Formula 1]SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for analyzing a maximum bending moment and a program for analyzing a maximum bending moment. [Background technology]

[0002] Conventionally, H-shaped steel beams in steel-frame buildings have been used in order to efficiently increase the bending stiffness and bending strength of the cross section, which allows for rational component design. With H-shaped steel, it is possible to freely change the combination of web and flange thicknesses, which makes it possible to streamline structural design by using, for example, extremely thin steel plates for the webs.

[0003] It is generally known that when external forces such as bending or compression act on a steel structural member with thin plate elements constituting the cross section of the member, local buckling occurs, causing the plate elements constituting the cross section to deform unevenly. It is also known that even after local buckling occurs, the member strength increases and reaches the maximum bending moment. When considering plate buckling, it is known that there is a good correlation between the square root of the ratio between the yield strength of the plate material and the elastic local buckling strength of the plate, and the effective width of the plate element (see, for example, non-patent document 1). [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] "Guide to the Design of Light-Gauge Steel Buildings," 2nd Edition, Gihodo Publishing, pp.52-56, edited by the National Institute for Land and Infrastructure Management, Ministry of Land, Infrastructure, Transport and Tourism, and Building Research Institute, Independent Administrative Institution, and edited by the Japan Iron and Steel Federation. Summary of the Invention [Problem to be solved by the invention]

[0005] However, Non-Patent Document 1 is intended for the design of cold-formed steel members (H-shaped steel). Therefore, it is assumed that the plate thickness within the member cross section is uniform and that the cross-sectional shape can be produced by bending a single continuous plate element. Therefore, for H-shaped steel, the plate thickness of which differs between the web and flange and whose cross-sectional shape cannot be produced by bending a single continuous plate element, there was no method for quantitatively and comprehensively evaluating the maximum bending moment.

[0006] The present invention has been made in consideration of the above problems, and has an object to provide a maximum bending moment analysis method and a maximum bending moment analysis program for quantitatively and comprehensively evaluating the maximum bending moment of H-shaped steel. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention proposes the following means. The method for analyzing maximum bending moment of the present invention is a method for evaluating the maximum bending moment of an H-shaped steel on which a bending moment acts, and the maximum bending moment that the H-shaped steel can exert is calculated based on the maximum strength calculated value M cal It is characterized by the evaluation by: where α and β are constants, and M y : yield bending moment of the H-shaped steel, M crl : Elastic local buckling strength of the H-shaped steel.

[0008]

number

[0009] The maximum bending moment analysis program of the present invention is a maximum bending moment analysis program for an analysis device that evaluates the maximum bending moment of an H-shaped steel on which a bending moment acts, and the analysis device is configured to calculate the maximum bending moment that the H-shaped steel can exert based on the calculated maximum strength M calIt is characterized by functioning as an analysis unit that evaluates the results by: where α and β are constants, and M y : yield bending moment of the H-shaped steel, M crl : Elastic local buckling strength of the H-shaped steel.

[0010]

number

[0011] Note that equation (1) is the same as equation (2). In these inventions, the inventors have found, as a result of extensive investigation, that in the case of plate buckling, a correlation is confirmed between the square root of the ratio of the yield strength of the plate material to the elastic local buckling strength of the plate, and the ratio of the effective width of the plate element to the original plate width of the plate element, whereas in the case of evaluating H-shaped steel as a whole, a favorable correlation is confirmed between the power root of the ratio of the yield bending moment of the H-shaped steel to the elastic local buckling strength of the H-shaped steel, and the maximum bending moment and the yield bending moment of the H-shaped steel.The inventors then found that, using constants α and β, the maximum bending moment of the H-shaped steel is calculated as the maximum strength calculated based on equation (1), M cal We found that it is possible to quantitatively evaluate the Therefore, the maximum bending moment of H-shaped steel can be evaluated quantitatively and comprehensively.

[0012] In the method for analyzing the maximum bending moment, the constant β may satisfy the formula (3). 0.02<β<0.5 (3) In this invention, the more precisely the elastic local buckling strength of the H-shaped steel is calculated by a method such as eigenvalue analysis, the more difficult it is to obtain the yield bending moment M y and elastic local buckling strength M crl The maximum bending moment can be precisely calculated based on the above.

[0013] In the method for analyzing the maximum bending moment, the constant α may satisfy the formula (4). 0<α<1.14β 2+0.579β+0.698 ··(4) In this invention, the maximum bending moment of the H-shaped steel is calculated by the formula (1) and the maximum strength M cal The calculated maximum strength M cal This allows for a conservative evaluation.

[0014] In the method for analyzing maximum bending moment, the thickness of the web of the H-shaped steel may be equal to or smaller than the thickness of each flange. In this invention, even if the H-shaped steel has the same cross-sectional area, the cross-sectional area on the flange side is made larger than that on the web, thereby improving the cross-sectional performance of the H-shaped steel, such as the moment of inertia of the area.In addition, when the H-shaped steel is manufactured by welding assembly, the entire thickness of the flange can be prevented from melting before the entire thickness of the web is completely melted, thereby suppressing damage to the flange.

[0015] In the method for analyzing maximum bending moment, the H-shaped steel may be a welded and assembled H-shaped steel in which a web and a pair of flanges are welded to each other. In the present invention, the thickness of the web can be made smaller than the thickness of each flange to an extent that the H-section steel cannot be manufactured by rolling.

[0016] In the method for analyzing maximum bending moment, the H-shaped steel may be used as a sub-beam. In the present invention, the H-shaped steel can be used as an elastic material that is not expected to have plastic deformation performance. Effect of the Invention

[0017] The maximum bending moment analysis method and maximum bending moment analysis program of the present invention make it possible to quantitatively and comprehensively evaluate the maximum bending moment of H-shaped steel. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a perspective view of an H-shaped steel evaluated by a maximum bending moment analysis method according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of the same H-shaped steel. [Diagram 3] FIG. 13 is a diagram showing the relationship between the constant β and the correlation coefficient obtained from the analysis result. [Figure 4] FIG. 13 is a diagram showing the relationship between the constant α and the average value of the maximum strength ratio, etc., obtained from the analysis results. [Diagram 5] FIG. 13 is a diagram showing the relationship between the constant β and the constant α when the minimum value of the maximum strength ratio is 1.0. [Figure 6] FIG. 13 is a diagram showing the relationship between the constant β and the constant α when the average maximum strength ratio is 1.0. [Figure 7] FIG. 1 is a diagram showing the change in (maximum bending moment / yield bending moment) with respect to the generalized width-thickness ratio λ. [Figure 8] FIG. 2 is a diagram showing an overview of a maximum bending moment analysis device that performs the maximum bending moment analysis method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, one embodiment of a method for analyzing maximum bending moment (hereinafter, simply referred to as an analysis method) according to the present invention will be described with reference to FIGS. 1 to 8. FIG.

[0020] [1. Structure of H-beam] This analysis method is used to evaluate the maximum bending moment of the H-shaped steel 10 shown in Fig. 1. The maximum bending moment of the H-shaped steel 10 here means the maximum value of the bending moment that the H-shaped steel can withstand when a bending moment acts on the H-shaped steel. For example, the H-shaped steel 10 extends along a horizontal plane in the material axis direction of the H-shaped steel 10. In this example, the H-shaped steel 10 is a welded and assembled H-shaped steel in which a web 11 and a pair of flanges 12, 13 are welded to each other. For example, the web 11 and the pair of flanges 12, 13 are made of a hot-rolled steel strip (not shown) (a strip-shaped material made of hot-rolled steel plate).

[0021] The web 11 is formed in a flat plate shape that is rectangular when viewed in the thickness direction of the web 11. The web 11 is disposed so that the thickness direction of the web 11 is along a horizontal plane. The flanges 12 and 13 are formed in a flat plate shape and are disposed so that the thickness direction of the flanges 12 and 13 is along the up-down direction. The flange 13 is disposed below the flange 12. The flanges 12 and 13 are disposed so as to sandwich the web 11 in the up-down direction. The web 11 is welded to the center of the width direction of the lower surface of the flange 12 and is welded to the center of the width direction of the upper surface of the flange 13.

[0022] The H-shaped steel 10 constructed as described above is used by joining a main beam (not shown) to both ends in the material axial direction. That is, the H-shaped steel 10 is used as a sub-beam. The main beam is supported by a column (not shown). A bending moment F1 acts on the H-shaped steel 10 via the girder. The bending moment F1 acts on the H-shaped steel 10 so as to bend the H-shaped steel 10 in a downward convex shape. At this time, the flange 12 is subjected to a compressive force, and the flange 13 is subjected to a tensile force.

[0023] [2. Conditions for elastic-plastic analysis of H-shaped steel] An elastic-plastic large deformation analysis (hereinafter simply referred to as analysis) was performed on the H-shaped steel 10 using the finite element method (FEM). The analysis was carried out using the cross-sectional shape of the H-shaped steel 10 and other parameters. Here, the dimensions of the H-shaped steel 10 are defined as shown in FIG. 2. The depth of the H-shaped steel 10 is H. The width of the H-shaped steel 10 is B. The thickness of the web 11 is t. w The thickness of each of the flanges 12 and 13 is t f Let us assume that. As shown in Fig. 1, the X-axis is defined as the direction along the thickness of the web 11. The Y-axis is defined as the material axis direction of the H-shaped steel 10. The Z-axis is defined as the direction along the thickness of the flanges 12, 13. The direction of the Z-axis from the flange 13 to the flange 12 is defined as positive. The positive directions of the X-axis, Y-axis, and Z-axis are defined so as to form a right-handed Cartesian coordinate system.

[0024] The length of the H-shaped steel 10 in the axial direction is set to 10 times the thickness H of the H-shaped steel 10. A uniform bending moment F1 is applied to the H-shaped steel 10. In addition, the joint 10a between the web 11 and the flange 12 was restrained from displacement in the in-plane direction of the flange 12. This eliminated the effect of lateral buckling of the H-shaped steel 10 (buckling due to displacement in the direction along the X-axis). The analytical parameters are shown in Table 1. In the H-shaped steel 10, the thickness t w is the thickness t of each flange 12, 13 f (t f ≧t w That is, the thickness t of the web 11 w is the thickness of flange 12, t f The same applies to the flange 13 as to the flange 12.

[0025] [Table 1]

[0026] The thickness H of the H-shaped steel 10 was set to 300 mm, 700 mm, and 1000 mm. The value of (B / H) obtained by dividing the width B of the H-shaped steel 10 by the depth H was set to 0.25, 0.5, 0.75, and 1 for each depth H. w The values ​​for each thickness H were 3.2mm, 4.5mm, 6mm, and 9mm. Thickness t of flanges 12 and 13 f The thicknesses t of the flanges 12 and 13 are 3.2 mm, 4.5 mm, 6 mm, 9 mm, 12 mm, and 16 mm, respectively, for the heights H of 300 mm and 1000 mm.f For a height of 700mm, the dimensions were 3.2mm, 4.5mm, 6mm, 9mm, 12mm, 16mm, 19mm, 22mm, and 25mm.

[0027] H-shaped steel 10: H, width B, thickness t w ,t f The elastic-plastic strength of the H-shaped steel 10 was quantitatively evaluated by changing the load. The H-shaped steel 10 is formed of a steel material. The steel material is assumed to exhibit a completely elastic-plastic stress-strain relationship. The yield strength of the material is σ y That is, the yield strength σ y is 235N / mm for 300mm and 1000mm heights 2 , 500N / mm 2 The yield strength σ y is 235N / mm for a height of 700mm 2 , 440N / mm 2 It was decided. Since the length of the H-shaped steel 10 in the material axis direction is 10 times the thickness H of the H-shaped steel 10, the restraint condition at the end of the H-shaped steel 10 in the material axis direction is the maximum bending moment M max The impact on the evaluation results is suppressed.

[0028] [3. Results of elastic-plastic analysis of H-shaped steel] [3.1. Consideration of the range of the constant β] For example, previous knowledge from Patent Document 1 reveals that the post-buckling strength of a plate element that has experienced local buckling is inversely proportional to the square root of the ratio between the yield strength (strength) of the plate element and the elastic local buckling strength. Therefore, the elastic local buckling strength M of H-shaped steel 10 obtained from the eigenvalue analysis of an H-shaped steel having the same shape, material, and boundary conditions as the analytical model in [2.] is crl Using the above, the maximum bending moment M of H-shaped steel 10 is calculated. max The calculated maximum strength of H-shaped steel 10 based on Eq. (11) M cal It was thought that this could be quantitatively evaluated.

[0029]

number

[0030] Here, α and β are constants. The constant α has a value greater than 0. M y is the yield bending moment of the H-shaped steel 10.

[0031] Here, the change in the constant β is the maximum strength calculated by Eq. (11) M cal and the maximum bending moment M obtained from analysis using FEM, etc. max The effect of the constant α on the correlation coefficient between the calculated maximum strength M cal and maximum bending moment M max It does not affect the correlation coefficient with the yield bending moment M y is determined from the cross-sectional shape of the H-shaped steel 10, and the elastic local buckling strength M crl is obtained from buckling eigenvalue analysis, etc. Therefore, the calculated maximum strength M cal and maximum bending moment M max The correlation coefficient between can be uniquely evaluated as the relationship between the constant β and the correlation coefficient. The maximum bending moment M obtained by analysis max is the yield bending moment M of H-shaped steel 10 y Regarding the analysis results that exceeded the above range, the data is not used (omitted) in the following processing since the purpose of the present invention is different from that of evaluating the degree of reduction in the section modulus.

[0032] The results are shown in Figure 3. In Figure 3, the horizontal axis represents the constant β, and the vertical axis represents the correlation coefficient. When applying the conventional plate theory to H-beam 10, the maximum bending moment M max is the yield bending moment M y and the elastic local buckling strength M crl The correlation coefficient is inversely proportional to the square root of the ratio (β = 0.5), and should be maximum when the constant β is 0.5. However, in the analysis results for H-shaped steel 10, this correlation coefficient reaches a maximum when the constant β is close to 0.25. Furthermore, when the constant β satisfies equation (12), it was found that an even stronger correlation can be obtained than with the evaluation method of the effective cross section based on the conventional plate theory (constant β is 0.5). 0.02<β<0.5 (12)

[0033] [3.2. Consideration of the range of the constant α] Next, the constant α will be considered. In FIG. 3, the condition where the constant β is 0.25, which gives the highest correlation coefficient, was examined. Here, the maximum bending moment M obtained by the analysis max The maximum strength calculated using Eq. (11) M cal Divided by (M max / M cal ) is called the maximum strength ratio. The change in the constant α is proportional to the calculated maximum strength M cal Maximum bending moment M max In order to investigate the effect on the evaluation accuracy of the maximum strength ratio, the value of the constant α that results in an average maximum strength ratio of 1 and the value of the constant α that results in a minimum maximum strength ratio of 1 were investigated. The analysis results are shown in Figure 4. In Figure 4, the horizontal axis represents the constant α, and the vertical axis represents the average and minimum maximum strength ratios. In Figure 4, the solid line L1 represents the average maximum strength ratio. The dashed line L2 represents the minimum maximum strength ratio.

[0034] From Figure 4, when the constant α is 0.914, the average value of the maximum strength ratio is 1.0. When the constant α is 0.761, the minimum value of the maximum strength ratio is 1.0. It was found that the average value of the maximum strength ratio was 1.0 or more by setting the constant α to 0.914 or less. In addition, the minimum value of the maximum strength ratio was 1.0 or more by setting the constant α to 0.761 or less. For all the analyzed H-shaped steels 10, the calculated maximum strength value M cal is the maximum bending moment M obtained by the analysis. max It turned out to be the following: Therefore, the desirable range of the constant α in this embodiment is greater than 0 and equal to or less than 0.914. Furthermore, if the constant α is greater than 0 and equal to or less than 0.761, the calculated maximum strength M calculated by the formula (11) will always be cal is the maximum bending moment M obtained by the analysis. max It can be evaluated as follows:

[0035] Next, the effect of changing the constant β on the optimal value of the constant α was examined. Here, the values ​​of constant α at which the minimum and average maximum strength ratios are 1.0 were investigated when constant β was changed within the range of 0.02 to 0.5. The results are shown in Fig. 5 and Fig. 6. Fig. 5 is a diagram showing the relationship between constant β and constant α when the minimum maximum strength ratio is 1.0. Fig. 6 is a diagram showing the relationship between constant β and constant α when the average maximum strength ratio is 1.0. When the minimum value of the maximum strength ratio is 1.0, as shown in Fig. 5, it can be confirmed that the value of constant α tends to increase with changes in constant β when the constant β is in the range of 0.02 to 0.5. It was found that the relationship between constant β and constant α can be approximated by a quadratic function, equation (15) (represented by the dashed line L4 in Fig. 5). α=1.14β 2 +0.579β+0.698 ··(15)

[0036] As mentioned above, the constant α is greater than 0. Therefore, when the constant α satisfies the formula (16), the maximum bending moment M obtained by the analysis is max The maximum strength calculated by Eq. (11) M cal will be greater than. 0<α<1.14β 2 +0.579β+0.698 ··(16)

[0037] Next, the relationship between constant β and constant α when the average maximum strength ratio is 1.0 was investigated. As shown in Figure 6, it was confirmed that the value of constant α increases with increasing constant β when constant β is in the range of 0.02 to 0.25. When constant β is in the range of 0.25 or more, the value of constant α becomes constant. From the above results, we assumed that the constant β ranged from 0.02 to 0.25 using a quadratic function with least squares approximation, and that the value of the constant α was constant when the constant β was 0.25 or more. In this case, it was found that the relationship between the constants β and α could be approximated by equations (17) and (18) (dotted lines L5 and L6 in Figure 6). When 0.02<β<0.25 α=4.6β 2 +0.858β+0.259 ··(17) When 0.25≦β<0.5 α = 0.761 (18)

[0038] In the analysis method of this embodiment, the maximum bending moment M that the H-shaped steel 10 can exert is calculated. max The calculated maximum strength M based on Eq. (11) cal An analysis step is performed to evaluate the above. Elastic local buckling strength M crl and yield bending moment M y is obtained from the cross-sectional shape of the H-shaped steel 10. For this reason, the user who performs this analysis method can, for example, determine the elastic local buckling strength M crl and yield bending moment M y In advance, the constant β is set to a value within the range obtained from equation (12) and the constant α is set to a value within the range obtained from equation (15). Then, the maximum strength M is calculated from equation (11). cal can be sought and evaluated.

[0039] [3.3. Evaluation of analytical methods] FIG. 7 shows the calculation results when the constant α is calculated from the formula (15) (shown by line L8) and when the constant α is calculated from the formula (18) (shown by line L9) under the condition that the constant β is 0.25. In FIG. 7, the horizontal axis shows the generalized width-thickness ratio λ, and the vertical axis shows the maximum bending moment M max / Yield bending moment M y ) value. The generalized width-thickness ratio λ is the yield bending moment M y is the elastic local buckling strength M crl It means the square root of the value divided by.

[0040] The circles and crosses in FIG. 7 indicate the results of multiple analyses calculated by changing the values ​​as shown in Table 1. max / M y ) is less than 1 and is used to calculate lines L8 and L9. On the other hand, the cross marks indicate that (M max / M y ) exceeds 1. The calculated maximum strength value M proposed by this invention cal is the maximum bending moment M of H-shaped steel 10 subjected to bending moment F1, regardless of the generalized width-thickness ratio λ. max This shows that the results are a good indicator for analyzing the

[0041] [4. Maximum bending moment analysis device and maximum bending moment analysis program] FIG. 8 shows a maximum bending moment analyzer (hereinafter simply referred to as the analyzer) 50 capable of preferably carrying out the above-mentioned analysis method. The analysis device 50 quantitatively evaluates the maximum bending moment of the H-shaped steel 10 on which the bending moment F1 acts. The analysis device 50 is a computer, and includes a CPU (Central Processing Unit) 51, a main memory device 55, an auxiliary memory device 60, an input / output interface (IO·I / F) 65, and a recording / playback device 70. The CPU 51, the main memory device 55, the auxiliary memory device 60, the input / output interface 65, and the recording / playback device 70 are connected to each other by a bus 75. The main storage device 55 is a RAM (Random Access Memory) or the like that serves as a work area for the CPU 51 . The input / output interface 65 is connected to an input device 66 such as a keyboard and a mouse, and a display device 67 . A recording / playback device 70 records and plays back data on a recording medium 71 such as a USB (Universal Serial Bus) memory.

[0042] The auxiliary storage device 60 is a hard disk drive device or the like in which various data, programs, etc. are stored. In the auxiliary storage device 60, a maximum bending moment analysis program (hereinafter simply referred to as analysis program) 61 for causing the computer to function as the analysis device 50, various programs such as an OS program, etc. are stored. The various programs including the analysis program 61 are loaded into the auxiliary storage device 60 from a recording medium 71 via a recording / playback device 70. The analysis program 61, etc. are stored in the recording medium 71. These programs may be loaded into the auxiliary storage device 60 from a disk-type recording medium such as a CD or DVD, or from an external device via a communication device (not shown).

[0043] The CPU 51 executes various calculation processes. The CPU 51 functionally includes an analysis unit 52. The analysis unit 52 calculates the maximum bending moment that the H-shaped steel 10 can exert based on the calculated maximum strength M cal Evaluate by. Analysis unit 52, which is a functional component of CPU 51, functions by CPU 51 executing analysis program 61 and the like stored in auxiliary storage device 60. Analysis program 61 and the like are programs for analysis device 50. Analysis program 61 causes analysis device 50 to function as analysis unit 52.

[0044] As described above, in the analysis method and analysis program 61 of this embodiment, the inventors have found, as a result of intensive research, that the power root of the ratio between the yield bending moment of the H-shaped steel 10 and the elastic local buckling strength of the H-shaped steel 10 shows a good correlation with the ratio between the maximum bending moment of the H-shaped steel 10 and the yield bending moment of the H-shaped steel 10. The inventors then found that the maximum bending moment M max The maximum strength calculated based on Eq. (11) using the constants α and β is M cal We found that it can be quantitatively evaluated by Therefore, the maximum bending moment M of H-shaped steel 10 max can be evaluated quantitatively and comprehensively.

[0045] In addition, when the constant β satisfies the formula (12), the yield bending moment M y and elastic local buckling strength M crl Based on the calculated maximum strength M cal When the maximum bending moment M of H-shaped steel 10 is calculated, max can be quantitatively evaluated with high accuracy. In addition, if the constant α satisfies equation (16), the maximum bending moment M obtained by analysis max is the maximum strength calculated using equation (11) M cal The maximum bending moment M max The calculated maximum strength M cal This allows for a conservative evaluation.

[0046] In the H-shaped steel 10, the thickness t of the web 11 w is the thickness t of each flange 12, 13 f As a result, the cross-sectional performance of the H-shaped steel 10, such as the moment of inertia of area, can be improved. The H-shaped steel 10 is a welded H-shaped steel. As a result, the thickness t of each flange 12, 13 is reduced to such an extent that the H-shaped steel 10 cannot be manufactured by rolling. f For the thickness t of web 11 w can be made thinner.

[0047] The H-shaped steel 10 is used as a small beam. Therefore, the H-shaped steel 10 can be used as an elastic material that is not expected to have plastic deformation performance.

[0048] Although one embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and changes, combinations, deletions, etc. of the configuration are also included within the scope that does not deviate from the gist of the present invention. For example, in the above embodiment, the constant β may be equal to or smaller than 0.02, or may be equal to or larger than 0.5. The constant α does not have to satisfy the formula (16). In the H-shaped steel 10, the thickness t of the web 11 w The thickness t of each flange 12, 13 fIt may be thicker than that. The H-shaped steel 10 may be a rolled H-shaped steel. The H-shaped steel 10 may be used as a girder, a purlin, a floor joist, a furring strip, a siding, a rafter, a corner post, or a foundation beam. [Explanation of symbols]

[0049] 10 H-shaped steel 11. Web 12,13 Flange 50 Analysis device (maximum bending moment analysis device) 52 Analysis Department 61 Maximum bending moment analysis program

Claims

1. A method for analyzing a maximum bending moment for evaluating a maximum bending moment of an H-shaped steel on which a bending moment acts, comprising the steps of: The maximum bending moment that the H-shaped steel can exert is calculated based on the formula (1) using the constant β that satisfies the formula (2) and the constant α that satisfies the formula (3), and the calculated value M of the maximum strength is calculated based on the formula (1). ｃａｌ This is an analytical method for evaluating maximum bending moment. where M y is the yield bending moment of the H-shaped steel, M ｃｒｌ : Elastic local buckling strength of the H-shaped steel. ０．０２＜β＜０．５ ・・（２） ０＜α＜１．１４β ２ ＋０．５７９β＋０．６９８ ・・（３） [0010]

2. The method for analyzing maximum bending moment according to claim 1 , wherein in the H-shaped steel, a thickness of the web is equal to or less than a thickness of each flange.

3. 3. The method for analyzing maximum bending moment according to claim 1, wherein the H-shaped steel is a welded H-shaped steel in which a web and a pair of flanges are welded to each other.

4. The method for analyzing maximum bending moment according to claim 1 , wherein the H-shaped steel is used as a sub-beam.

5. A maximum bending moment analysis program for an analysis device that evaluates the maximum bending moment of an H-shaped steel subjected to a bending moment, comprising: The analytical device, The maximum bending moment that the H-shaped steel can exert is calculated based on the formula (4) using the constant β that satisfies the formula (5) and the constant α that satisfies the formula (6), and the calculated maximum strength M ｃａｌ The maximum bending moment analysis program acts as the analysis part to evaluate by. where M y is the yield bending moment of the H-shaped steel, M ｃｒｌ : Elastic local buckling strength of the H-shaped steel. ０．０２＜β＜０．５ ・・（５） ０＜α＜１．１４β ２ ＋０．５７９β＋０．６９８ ・・（６） [0025]

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