Design method and manufacturing method for concrete-filled welded box-shaped cross section member, and concrete-filled welded box-shaped cross section member

Abstract

The present invention provides a design method and manufacturing method for a concrete-filled welded box-shaped cross-sectional member, as well as a concrete-filled welded box-shaped cross-sectional member, which can appropriately calculate the maximum concrete pouring height into the interior of a welded box-shaped cross-sectional member in which the corner welds are joined by partial penetration welding. [Solution] A design method for a concrete-filled welded box-shaped cross-sectional member, in which concrete is poured into the interior of a welded box-shaped cross-sectional member, the corner welds being joined by partial penetration welding, wherein a cross-sectional model is set in which the corners of the cross-section of the welded box-shaped cross-sectional member are rotational springs and the flat portions of the cross-section are bending elastic beams, the amount of deformation and stress generated in the cross-section when the pressure of the concrete poured into the interior of the welded box-shaped cross-sectional member acts on the cross-section is calculated using the cross-sectional model, and the maximum pouring height of the concrete is calculated such that the calculated amount of deformation is less than the allowable deformation of the cross-section and the calculated stress is less than the allowable stress of the cross-section.

Description

[Technical Field]

[0001] The present invention relates to a method for designing and manufacturing a concrete-filled, welded, assembled box-shaped cross-sectional member, as well as to a concrete-filled, welded, assembled box-shaped cross-sectional member. [Background technology]

[0002] High-rise buildings often use welded box-section members for their columns, as these allow for increased strength and larger cross-sections. In particular, the lower floors of super high-rise buildings utilize concrete-filled welded box-section members, which have increased rigidity, load-bearing capacity, and deformation capacity by filling the interior with concrete.

[0003] Here, as shown in Figure 1(a), when concrete 13 is filled into the interior of the welded box-shaped cross-section member 10, the dynamic pressure of the concrete injection and the hydrostatic pressure due to the liquid pressure of the fresh concrete act on the cross-section of the welded box-shaped cross-section member 10. Then, as shown in Figure 1(b), deformation and stress occur in the cross-section of the welded box-shaped cross-section member 10. For this reason, it is necessary to prevent excessive deformation and plastic deformation of the welded box-shaped cross-section member 10.

[0004] In this regard, Non-Patent Document 1 describes a method for calculating the maximum concrete pouring height into the interior of a steel column. In Non-Patent Document 1, the lateral pressure acting on the cross-section of the steel column is evaluated as a hydraulic pressure, considering the concrete as a complete liquid, and it is assumed that the pressure distribution is triangular in the height direction. Then, using a cross-sectional model in which each side of the cross-section of the steel column is a fixed beam at both ends, the maximum concrete pouring height into the interior of the steel column is calculated.

[0005] Furthermore, Non-Patent Document 2 describes a method for calculating the maximum concrete pouring height into a welded box-shaped cross section member where the corner welds are joined by partial penetration welding. In Non-Patent Document 2, instead of using the plate thickness of the skin plate of the welded box-shaped cross section member, the penetration depth of the corner weld is used as the beam depth of the fixed-end beam in the cross section model of Non-Patent Document 1. This allows for a conservative evaluation of the cross section performance of the welded box-shaped cross section member, and the maximum concrete pouring height is calculated.

[0006] Furthermore, Patent Document 1 proposes a construction method for concrete-filled steel pipe members, in which deformation of the steel pipe is suppressed by pressing the sides of the steel pipe toward the center using a jig when filling the square steel pipe with concrete. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 11-125013 [Non-patent literature]

[0008] [Non-Patent Document 1] Architectural Institute of Japan (ed.), "Design and Construction Guidelines for Concrete-Filled Steel Pipe Structures, 2nd Edition," Architectural Institute of Japan, October 2008, pp. 280-283. [Non-Patent Document 2] National Institute for Land and Infrastructure Management, Ministry of Land, Infrastructure, Transport and Tourism; Building Research Institute, Japan Building Administration Conference; Urban Housing Evaluation Center; New Urban Housing Association (eds.), "Application and Calculation Examples of Technical Standards and Commentary for Concrete-Filled Steel Tube (CFT) Construction," New Urban Housing Association, June 2008, pp. 2-50~2-51. [Non-Patent Document 3] Yasumichi Kamishiro, et al., "Experimental Study on Concrete Filling for CFT Structures: Part 2 - Verification of Constructability and Filling Properties of Steel Pipe Columns with Overcrowded Diaphragms," Proceedings of the Architectural Institute of Japan Academic Conference (Tohoku), August 2000, pp. 897-898. [Overview of the Initiative] [Problems that the invention aims to solve]

[0009] However, when calculating the maximum concrete pouring height into the interior of a welded box-shaped cross-sectional member, where the corner welds are joined by partial penetration welding, using the evaluation method described in Non-Patent Document 2, the following problems arise.

[0010] As described above, in the method described in Non-Patent Document 2, the penetration depth of the corner weld is used as the beam depth of the fixed-end beam in the cross-sectional model of Non-Patent Document 1, instead of the plate thickness of the skin plate of the welded box-shaped cross-sectional member. Therefore, in the method described in Non-Patent Document 2, the shear stiffness of the flat plate portion and the rotational stiffness of the corner weld of the welded box-shaped cross-sectional member are not properly reflected in the cross-sectional model. Consequently, the evaluation of the cross-sectional performance of the welded box-shaped cross-sectional member may be overly conservative, or conversely, depending on the parameters, may be overly conservative.

[0011] If the cross-sectional performance of a welded box-section member is overly conservatively evaluated, the maximum concrete pouring height that can be poured into the interior of the welded box-section member at one time will be calculated to be overly conservative. As a result, the efficiency of concrete filling into the interior of the welded box-section member will be significantly reduced, leading to an increase in on-site construction days and costs. Conversely, if the cross-sectional performance of the welded box-section member is overly conservatively evaluated, the deformation of the welded box-section member due to the pressure of the concrete poured inside may be greater than expected, or the welded box-section member may be damaged.

[0012] In view of the above-mentioned problems, the present invention aims to provide a method for designing and manufacturing a concrete-filled welded box-shaped cross-sectional member, as well as a concrete-filled welded box-shaped cross-sectional member, which can appropriately calculate the maximum concrete pouring height into the interior of a welded box-shaped cross-sectional member in which the corner welds are joined by partial penetration welding. [Means for solving the problem]

[0013] To solve the above problems, the present invention has the following features.

[0014] [1] A design method for a concrete-filled welded box-shaped cross section member, wherein concrete is poured into the interior of a welded box-shaped cross section member, the corners of the cross section of the welded box-shaped cross section member being rotate springs and the flat portions of the cross section being bending elastic beams; a cross section model is set up in which the corners of the cross section of the welded box-shaped cross section member are rotate springs and the flat portions of the cross section are bending elastic beams; the amount of deformation and stress generated in the cross section when the pressure of the concrete poured into the interior of the welded box-shaped cross section member acts on the cross section is calculated using the cross section model; and the maximum pouring height of the concrete is calculated such that the calculated amount of deformation is less than the allowable deformation of the cross section and the calculated stress is less than the allowable stress of the cross section.

[0015] The "maximum pouring height" mentioned above refers to the maximum height to which concrete can be poured at once into the interior of a welded box-shaped cross-section member. In other words, the pouring height of concrete poured at once into the interior of a welded box-shaped cross-section member is set to be less than or equal to the "maximum pouring height" mentioned above.

[0016] [2] Bending stiffness K of the bending elastic beam in the cross-sectional model m (N·mm 2 ) is given by the following equation (1)

[0017]

number

[0018] A design method for a concrete-filled welded box-shaped cross section member described in [1], which satisfies the following conditions.

[0019] However, in equation (1) above, w(N / mm 2) is the pressure applied to the flat plate portion when the pressure of the concrete placed inside the welded and assembled box-shaped cross-sectional member acts on the cross-section, D (mm) is the width of the welded and assembled box-shaped cross-sectional member, t (mm) is the plate thickness of the welded and assembled box-shaped cross-sectional member, t w (mm) is the penetration depth of the fillet weld, E (N / mm 2 ) is the Young's modulus of the steel material constituting the flat plate portion, I (mm 4 ) is the second moment of area of the flat plate portion, C m (dimensionless) is the coefficient calculated by the following formula (2)

[0020]

Equation

[0021] and is a parameter determined by performing multiple regression analysis on a data group including the ratio D / t of the width D (mm) to the plate thickness t (mm) of the welded and assembled box-shaped cross-sectional member and the ratio t w (mm) to the plate thickness t (mm), t w / t, which are obtained by conducting experiments or numerical analyses on the welded and assembled box-shaped cross-sectional member.

[0022] [3] The design method of the concrete-filled welded and assembled box-shaped cross-sectional member according to [2], wherein the values of the parameters a, b, and c are respectively set within the ranges of 0.020 ≤ a ≤ 0.050, 0.010 ≤ b ≤ 0.015, and 0.60 ≤ c ≤ 0.80.

[0023] [4] The design method of the concrete-filled welded and assembled box-shaped cross-sectional member according to [2], wherein the values of the parameters a, b, and c are respectively set to a = 0.029, b = 0.012, and c = 0.72.

[0024] [5] The maximum driving height h (mm) is calculated by the following formula (3)

[0025]

Equation

[0026] A design method for concrete-filled welded box-shaped cross section members, calculated according to any of [1] to [4].

[0027] However, in equation (3) above, S1 (dimensionless) is the safety factor, D (mm) is the width of the welded box-shaped cross section member, t (mm) is the plate thickness of the welded box-shaped cross section member, and E (N / mm) 2 ) is the Young's modulus of the steel material constituting the flat plate portion, and v c (mm) is the allowable deformation amount at the center position in the width direction of the welded assembly box-shaped cross section member, where ρ (kg / mm) is the allowable deformation amount. 2 ) is the density of concrete, g(mm / s²). 2 ) is the acceleration due to gravity, and C m (Dimensionless) is given by equation (2) below.

[0028]

number

[0029] The coefficient is calculated by the above equation (2), where a, b, and c are the ratio D / t of the width D (mm) to the plate thickness t (mm) of the welded box-shaped cross section member, and the penetration depth t of the corner weld, respectively, obtained by conducting experiments or numerical analysis on the welded box-shaped cross section member. w (mm) and the ratio of plate thickness t (mm) w This parameter is determined by performing multiple regression analysis on a dataset that includes / t.

[0030] [6] The maximum driving height h (mm) is given by the following formula (4)

[0031]

number

[0032] A design method for concrete-filled welded box-shaped cross section members, calculated according to any of [1] to [4].

[0033] However, h in equation (4) above v h s1 h s2 These are, respectively, equations (5) to (7) below.

[0034]

number

[0035]

number

[0036]

number

[0037] The value is calculated by the above equations (5) to (7), where S1 to S3 (dimensionless) are safety factors, D (mm) is the width of the welded box-shaped cross section member, t (mm) is the plate thickness of the welded box-shaped cross section member, and t w (mm) is the penetration depth of the corner weld, and E(N / mm) 2 ) is the Young's modulus of the steel material constituting the flat plate portion, and v c (mm) is the allowable deformation amount at the center position in the width direction of the welded assembly box-shaped cross section member, σ y (N / mm 2 ) is the yield strength of the steel material constituting the flat plate portion, σ yw (N / mm 2 ) is the yield strength of the corner weld, where ρ (kg / mm²) is the yield strength of the corner weld. 2 ) is the density of concrete, g(mm / s²). 2 ) is the acceleration due to gravity, and C m (Dimensionless) is given by equation (2) below.

[0038]

number

[0039] The coefficient is calculated by the above equation (2), where a, b, and c are the ratio D / t of the width D (mm) to the plate thickness t (mm) of the welded box-shaped cross section member, and the penetration depth t of the corner weld, respectively, obtained by conducting experiments or numerical analysis on the welded box-shaped cross section member. w (mm) and the ratio of plate thickness t (mm) w This parameter is determined by performing multiple regression analysis on a dataset that includes / t.

[0040] [7] A method for manufacturing a concrete-filled welded box-shaped cross section member, wherein concrete is poured into the interior of a welded box-shaped cross section member, the corner welds of which are joined by partial penetration welding, the method comprising: setting up a cross section model in which the corners of the cross section of the welded box-shaped cross section member are rotational springs and the flat plate portions of the cross section are bending elastic beams; calculating the amount of deformation and stress generated in the cross section when the pressure of the concrete poured into the interior of the welded box-shaped cross section member acts on the cross section using the cross section model; calculating the maximum pouring height of the concrete such that the calculated amount of deformation is less than the allowable deformation of the cross section and the calculated stress is less than the allowable stress of the cross section; and pouring concrete into the interior of the welded box-shaped cross section member at a height less than or equal to the calculated maximum pouring height to manufacture the concrete-filled welded box-shaped cross section member.

[0041] [8] A concrete-filled welded box-shaped cross-sectional member having corner welds joined by partial penetration welding, wherein concrete is poured into the interior of the welded box-shaped cross-sectional member, the height of the concrete poured into the interior of the welded box-shaped cross-sectional member is set to such a dimension that the amount of deformation generated in the cross-section due to the pressure of the concrete is less than the allowable deformation of the cross-section, calculated using a cross-sectional model in which the corners of the cross-section of the welded box-shaped cross-sectional member are rotational springs and the flat portions of the cross-section are bending elastic beams, and the stress generated in the cross-section due to the pressure of the concrete is less than the allowable stress of the cross-section, calculated using the cross-sectional model. [Effects of the Invention]

[0042] According to the design method and manufacturing method for concrete-filled welded box-shaped cross-sectional members of the present invention, and the concrete-filled welded box-shaped cross-sectional members themselves, the shear stiffness of the flat plate portion and the rotational stiffness of the corner welds of the welded box-shaped cross-sectional member, where the corner welds are joined by partial penetration welding, are appropriately reflected in the cross-sectional model. Therefore, the maximum concrete pouring height into the interior of the welded box-shaped cross-sectional member, where the corner welds are joined by partial penetration welding, can be appropriately calculated.

[0043] Based on the maximum concrete pouring height calculated in this way, a concrete-filled, welded, assembled box-shaped cross-section member can be manufactured (constructed), significantly reducing the construction time required for concrete pouring and enabling more efficient construction. [Brief explanation of the drawing]

[0044] [Figure 1] Figure 1(a) schematically shows the pressure distribution acting on the cross-section of a welded box-shaped cross-section member from the concrete filled inside the member. Figure 1(b) schematically shows the load acting on the cross-section of the welded box-shaped cross-section member and the deformation occurring in the cross-section of the welded box-shaped cross-section member. Figure 1(c) schematically shows a cross-sectional model in which the corners of the cross-section of the welded box-shaped cross-section member are used as rotational springs and the flat sections of the same cross-section are used as bending elastic beams. [Figure 2] Figure 2(a) schematically shows the load acting on the cross-section of a welded box-shaped cross-section member, and Figure 2(b) schematically shows a cross-sectional model in which the corners of the cross-section of the welded box-shaped cross-section member are used as rotational springs and the flat sections of the same cross-section are used as bending elastic beams. [Figure 3] Figures 3(a) to 3(d) schematically show the bending moment distribution, bending deformation distribution, shear deformation distribution, and axial deformation distribution that occur in the cross-sectional model of a welded box-shaped cross-sectional member, respectively. [Figure 4] Figure 4 shows a finite element analysis model of a welded box-section member subjected to pressure from concrete filled inside the welded box-section member. [Figure 5] Figures 5(a) and 5(b) are graphs showing the bending stiffness of the cross-sectional model of a welded box-shaped cross-sectional member calculated by the design method for concrete-filled welded box-shaped cross-sectional members of the present invention, compared with analytical values ​​obtained by the finite element method and calculated values ​​obtained by Non-Patent Document 2. [Figure 6] Figures 6(a) and 6(b) are graphs showing the maximum concrete pouring height calculated by the design method for concrete-filled welded box-shaped cross section members of the present invention. [Figure 7] Figure 7 is a graph showing the maximum concrete pouring height calculated by the design method for concrete-filled, welded, box-shaped cross-sectional members of the present invention, compared with the calculated value according to Non-Patent Document 2. [Modes for carrying out the invention]

[0045] The design method and manufacturing method of the concrete-filled, welded, assembled box-shaped cross-sectional member of the present invention, as well as one embodiment of the concrete-filled, welded, assembled box-shaped cross-sectional member, will be described in detail below with reference to the drawings.

[0046] Figure 1(a) schematically shows the pressure distribution acting on the cross-section of the welded box-shaped cross-section member 10 from the concrete 13 filled inside the welded box-shaped cross-section member 10 during its manufacture (construction). Figure 1(b) schematically shows the load acting on the cross-section of the welded box-shaped cross-section member 10 and the deformation occurring in the cross-section of the welded box-shaped cross-section member 10.

[0047] As shown in Figure 1(b), the concrete-filled welded box-shaped cross-sectional member 1 designed using the design method for concrete-filled welded box-shaped cross-sectional members of this embodiment is constructed by pouring concrete 13 inside the welded box-shaped cross-sectional member 10. The welded box-shaped cross-sectional member 10 is constructed by joining four skin plates 11 together to form a rectangular cross-section, with the corner welds 12 joined by partial penetration welding.

[0048] Figure 1(c) schematically shows a cross-sectional model 20 of a welded box-shaped cross-sectional member 10 used in the design method of the concrete-filled welded box-shaped cross-sectional member of this embodiment.

[0049] As shown in Figure 1(c), in the design method for concrete-filled welded box-shaped cross section members of this embodiment, a cross section model 20 is set in which the corners of the cross section of the welded box-shaped cross section member 10 are made into rotating springs 21, and the flat plate portions of the cross section of the welded box-shaped cross section member 10 are made into bending elastic beams 22. Then, the amount of deformation and stress generated in the cross section when the pressure of the concrete 13 poured inside the welded box-shaped cross section member 10 acts on the cross section of the welded box-shaped cross section member 10 is calculated using the above-mentioned cross section model 20. Furthermore, the maximum pouring height h of the concrete 13 is calculated such that the calculated amount of deformation of the cross section of the welded box-shaped cross section member 10 is less than the allowable deformation of the cross section, and the calculated stress in the cross section of the welded box-shaped cross section member 10 is less than the allowable stress of the cross section.

[0050] At this time, the bending stiffness K of the bending elastic beam 22 in the cross-sectional model 20 m (N·mm 2 ) is given by the following equation (1)

[0051]

number

[0052] It is preferable to use a value that satisfies the following condition.

[0053] However, in equation (1) above, w(N / mm 2 ) is the pressure applied to the flat plate portion of the cross-section when the pressure of the concrete 13 poured inside the welded box-shaped cross-section member 10 acts on the cross-section of the welded box-shaped cross-section member 10. Also, D (mm) is the width of the welded box-shaped cross-section member 10, and t (mm) is the plate thickness of the welded box-shaped cross-section member 10. w (mm) represents the penetration depth of the corner weld 12. Also, E(N / mm) 2 ) is the Young's modulus of the steel material that constitutes the flat plate portion of the cross-section of the welded box-shaped cross-section member 10, where I(mm 4 ) is the second moment of area of ​​the flat plate portion. Also, C m (Dimensionless) is given by equation (2) below.

[0054]

number

[0055] This coefficient is calculated by the above equation (2). a, b, and c are parameters obtained by conducting experiments or numerical analyses on the welded box-shaped cross section member 10. Parameters a, b, and c are the ratio D / t of the width D (mm) to the plate thickness t (mm) of the welded box-shaped cross section member 10, and the penetration depth t of the corner weld 12. w (mm) and the ratio of plate thickness t (mm) w The value is determined by performing multiple regression analysis on the data set containing / t. Note that the right-hand side of equation (2) above (function MIN) represents the minimum value of the values ​​listed in parentheses.

[0056] Equations (1) and (2) above will be explained in detail below.

[0057] The inventors investigated a method for accurately designing the maximum concrete pouring height into a welded box-shaped cross section member 10, in which the corner welds 12 are joined by partial penetration welding.

[0058] Figure 2(a) schematically shows the loads acting on the cross-section of the welded box-shaped cross-section member 10. Figure 2(b) schematically shows a cross-sectional model 20 in which the corners of the cross-section of the welded box-shaped cross-section member 10 are used as rotary springs 21 and the flat plate portion of the same cross-section is used as a bending elastic beam 22.

[0059] In this study, as shown in Figure 2(b), the cross-section of a welded box-shaped cross section member 10 with width D (mm) and plate thickness t (mm) was modeled by dividing the cross-section into eight parts. Specifically, half of one of the four skin plates 11 constituting the welded box-shaped cross section member 10 was modeled as a bending elastic beam 22 with length (D-2t) / 2 (mm) and beam depth t (mm). In the cross-sectional model 20 modeled in this way, one end of the bending elastic beam 22, which corresponds to the corner of the cross-section of the welded box-shaped cross section member 10, has a rotational stiffness K r (N·mm 2 It was assumed that the bending elastic beam 22 was fixed by a rotating spring 21. The other end of the bending elastic beam 22 was supported by a roller 23 that was fixed in the rotational direction and the longitudinal direction of the bending elastic beam 22 (X direction in Figure 2(b)), but allowed to move in the beam depth direction of the bending elastic beam 22 (Y direction in Figure 2(b)). The bending elastic beam 22 was subjected to a uniformly distributed load w (N / mm) over its entire length (D-2t) / 2 (mm) by the pressure of the concrete 13 filled inside the welded assembled box-shaped cross section member 10. It was assumed that the change in the uniformly distributed load w (N / mm) in the beam width direction of the bending elastic beam 22 (Z direction in Figure 2(b)), which corresponds to the material axis direction of the welded assembled box-shaped cross section member 10, was small, and the length of the bending elastic beam 22 in the Z direction was assumed to be a unit length (mm).

[0060] Figures 3(a) to 3(d) schematically show the bending moment distribution, bending deformation distribution, shear deformation distribution, and axial deformation distribution occurring in the cross-sectional model 20 of the welded box-shaped cross-sectional member 10, respectively.

[0061] As shown in Figures 3(a) to 3(c), a uniformly distributed load w (N / mm) acts on the flexible elastic beam 22, causing bending moment, bending deformation, and shear deformation. Furthermore, as shown in Figure 3(d), the flexible elastic beam 22 undergoes axial deformation due to the uniformly distributed load w (N / mm) acting on other skin plates 11 that are joined at a right angle via the corner welds 12 of the welded box section member 10.

[0062] Bending moment M(x)(N·mm) and bending deformation v in the bending elastic beam 22. m (x)(mm), shear deformation v s (x)(mm), axial deformation v n (x)(mm) are given by equations (11) to (14) below.

[0063]

number

[0064]

number

[0065]

number

[0066]

number

[0067] However, in equations (11) to (14) above, x (mm) is the distance from one end of the bending elastic beam 22, i.e., from the rotating spring 21, and A (mm 2 ) is the cross-sectional area of ​​the bending elastic beam 22. Also, E(N / mm²) 2 ) is the Young's modulus of the bending elastic beam 22, and G(N / mm²) 2 ) is the shear modulus of the bending elastic beam 22, and I(mm 4 ) is the second moment of area of ​​the bending elastic beam 22.

[0068] The deformation of the bending elastic beam 22 is maximum at the center position in the width direction of the welded assembled box-shaped section member 10, i.e., at the position x = (Dt) / 2 (mm). The amount of deformation v of the bending elastic beam 22 at the center position in the width direction of the welded assembled box-shaped section member 10. c (mm) is given by the following equation (15).

[0069]

number

[0070] From equation (15) above, the uniformly distributed load w (N / mm) and the amount of deformation v of the bending elastic beam 22 at the widthwise center position of the welded box-shaped cross section member 10 are obtained. c The relationship between (mm) is given by the stiffness K (N / mm) of the bending elastic beam 22. 2 Expressed using ), it is as shown in equation (16) below.

[0071]

number

[0072] In equation (16) above, the stiffness K of the bending elastic beam 22 is given by N / mm 2 ) of which bending stiffness K m (N·mm 2 Focusing only on the ) part, we get the following equation (1).

[0073]

number

[0074] Here, C in equation (1) above m (Dimensionless) is given by equation (17) below.

[0075]

number

[0076] The coefficient is expressed as follows.

[0077] In equation (17) above, the rotational stiffness K of the rotating spring 21 r (N / mm 2 The calculation of the theoretical value of ) is complex, and C based on this theoretical value is m The calculation of C is also complex. m For this, we decided to use approximate values ​​obtained by performing numerical analysis on the welded assembled box-shaped cross section member 10.

[0078] First, C m This is the bending stiffness K when both ends of the bending elastic beam 22 are rotated springs, with the case where both ends of the bending elastic beam 22 are fixed as the reference. m (N·mm 2 Since it is a reduction factor, C m ≤ 1. Also, C m and rotational stiffness K of the rotating spring 21 r (N·mm 2 ) is the ratio of the amount of penetration between the base material and the welding material in the corner weld 12, i.e., the penetration depth t of the corner weld 12. w (mm) and the ratio of plate thickness t (mm) w It is thought that this is strongly influenced by / t and the ratio D / t of the width D (mm) to the plate thickness t (mm) of the welded assembled box-shaped cross section member 10. Therefore, C m We decided to use the value expressed by equation (2) below.

[0079]

number

[0080] Here, a, b, and c in equation (2) above are the ratio t, respectively. w This parameter is determined by performing multiple regression analysis on a data set with parameters / t and D / t. In this embodiment, the above ratio t w The data set including / t and D / t was obtained by performing a numerical analysis on the welded assembled box-shaped cross section member 10, which is subjected to pressure by the concrete 13 filled inside the welded assembled box-shaped cross section member 10.

[0081] Figure 4 shows a finite element analysis model of a welded box-shaped cross section member 10 that is subjected to pressure by concrete 13 filled inside the welded box-shaped cross section member 10.

[0082] As shown in Figure 4, a parametric study finite element analysis was performed on an analytical model of a welded box-shaped cross section member 10 that is subjected to pressure by concrete 13 filled inside the welded box-shaped cross section member 10. Specifically, the width D (mm) of the welded box-shaped cross section member 10 was set to three types: 400 mm, 600 mm, and 800 mm, the plate thickness (mm) was set to two types: 40 mm and 80 mm, and the penetration depth t of the corner weld 12 was set. w (mm)w was set to four types: 0mm, 10mm, 20mm, 30mm, and 40mm. For each of these combinations, the uniformly distributed load w (N / mm) due to the pressure of the concrete 13 and the amount of deformation v of the bending elastic beam 22 at the widthwise center position of the welded assembled box-shaped section member 10 were determined. c The relationship with (mm) was obtained. These analysis results were combined with equations (16) and (1) above, and the above ratio t w A dataset was obtained with parameters / t and D / t. Multiple regression analysis was performed on this dataset to determine the values ​​of parameters a, b, and c.

[0083] Multiple regression analysis of the finite element method results shows that it is preferable to set the values ​​of parameters a, b, and c within the ranges of 0.020≦a≦0.050, 0.010≦b≦0.015, and 0.60≦c≦0.80, respectively. In this way, the bending stiffness K of the bending elastic beam 22 according to equations (1) and (2) above is obtained. m (N·mm 2 The calculated value can be kept within an error range of approximately ±10% compared to the analytical value obtained by the finite element method.

[0084] In particular, when a=0.029, b=0.012, and c=0.72, the bending stiffness K of the bending elastic beam 22 according to equations (1) and (2) above is m (N·mm 2The calculated value of ) corresponds well to the analytical value obtained by the finite element method. Therefore, the values ​​of parameters a, b, and c are set to a=0.029, b=0.012, and c=0.72, respectively, and C m It is particularly preferable to use the value expressed by equation (2') below.

[0085]

number

[0086] Furthermore, in the design method for the concrete-filled, welded box-shaped cross-sectional member of this embodiment, the maximum concrete pouring height h (mm) of the concrete 13 is given by the following equation (3):

[0087]

number

[0088] It is preferable to calculate it by the following method.

[0089] However, in equation (3) above, S1 (dimensionless) is the safety factor. Also, D (mm) is the width of the welded box-shaped cross section member 10, and t (mm) is the plate thickness of the welded box-shaped cross section member 10. Also, E (N / mm 2 ) is the Young's modulus of the steel material that constitutes the flat plate portion, i.e., the skin plate 11 of the welded assembled box-shaped cross section member 10. Also, v c (mm) is the allowable deformation at the center position in the width direction of the welded box-shaped cross section member 10. Also, ρ (kg / mm) 2 ) is the density of concrete 13. Also, g(mm / s 2 ) is the acceleration due to gravity. Also, C m This is the coefficient calculated by equation (2) above.

[0090] Alternatively, in the design method for the concrete-filled welded box-shaped cross section member of this embodiment, the maximum concrete pouring height h (mm) of the concrete 13 is given by the following equation (4):

[0091]

number

[0092] It is preferably calculated by

[0093] However, h in the above formula (4) v h s1 h s2 are respectively the following formulas (5) to (7)

[0094]

Number

[0095]

Number

[0096]

Number

[0097] are values calculated by

[0098] However, in the above formulas (5) to (7), S1 to S3 (dimensionless) are safety factors. Also, D (mm) is the width of the welded and assembled box-shaped cross-sectional member 10, t (mm) is the plate thickness of the welded and assembled box-shaped cross-sectional member 10, and t w (mm) is the penetration depth of the fillet weld 12. Also, E (N / mm 2 ) is the Young's modulus of the steel material constituting the flat plate part, that is, the skin plate 11 of the welded and assembled box-shaped cross-sectional member 10. Also, v c (mm) is the allowable deformation amount at the center position in the width direction of the welded and assembled box-shaped cross-sectional member 10. Also, σ y (N / mm 2 ) is the yield strength of the steel material constituting the flat plate part, that is, the skin plate 11 of the welded and assembled box-shaped cross-sectional member 10, and σ yw (N / mm 2 ) is the yield strength of the fillet weld 12. Also, ρ (kg / mm 2) is the density of the concrete 12. Also, g (mm / s 2 ) is the acceleration due to gravity. Also, C m is the coefficient calculated by the above equation (2).

[0099] The above equations (4) to (7) will be specifically described below.

[0100] Assuming the length of the bending elastic beam 22 in the Z direction as the unit length (mm), the cross-sectional area A (mm 2 ) of the bending elastic beam 22 is A = t×1, and the second moment of area I (mm 4 ) of the bending elastic beam 22 is I = t 3 ×(1 / 12). Also, assuming the Poisson's ratio of the steel material is 0.3, the relationship between the shear modulus G (N / mm 2 ) and the Young's modulus E (N / mm 2 ) is expressed as G = E / {2(1 + 0.3)}. Substituting the above equations into the above equation (16), the following equation (18) is obtained.

[0101]

Equation

[0102] As shown in the above equation (18), the relationship between the uniformly distributed load w (N / mm) due to the pressure of the concrete 13 and the deformation amount v c (mm) at the center position in the width direction of the welded assembled box-shaped cross-sectional member 10 was obtained.

[0103] Similarly, when the welded assembled box-shaped cross-sectional member 10 is plasticized due to the pressure of the concrete 13 filled inside the welded assembled box-shaped cross-sectional member 10, the uniformly distributed load w (N / mm) was examined based on the above equation (11).

[0104] From the relationship between the above equation (11) and the above equation (17), the following equation (19) is derived.

[0105]

Equation

[0106] Of the flexible elastic beam 22, the position where the bending moment is maximum is either one end of the flexible elastic beam 22 (position x=0), that is, the corner welded portion 12 of the welded assembled box-shaped cross section member 10, or the other end (position x=(Dt) / 2), that is, the widthwise center position of the welded assembled box-shaped cross section member 10.

[0107] From equation (19) above, the yield moments |M(0)|(N·mm) and |M((D-2t) / 2)|(N·mm) at one end and the other end of the bending elastic beam 22 are given by equations (20) and (21) below, respectively.

[0108]

number

[0109]

number

[0110] Furthermore, the plate thickness of the welded box-shaped cross section member 10 is t (mm), and the penetration depth of the corner weld 12 is t w Assuming (mm), the cross-section of the bending elastic beam 22 in the cross-sectional model 20 of the welded box-shaped cross-sectional member 10 is t at the corner weld 12. w The dimensions are (mm) × 1 (mm), and in the flat section, t (mm) × 1 (mm). At this time, the flat section of the cross-section of the welded box-shaped cross-section member 10, that is, the skin plate 11 of the welded box-shaped cross-section member 10, is subjected to an axial force N = w(D-2t) / 2 and a bending moment. Therefore, the yield moment M of one end and the other end of the bending elastic beam 22 yc (N·mm), M yp (N·mm) is given by equations (22) and (23) below, respectively.

[0111]

number

[0112]

number

[0113] However, in equations (22) and (23) above, σ yw (N / mm 2 ) is the yield strength of the corner weld 12, and σ y (N / mm 2 ) is the yield strength of the flat plate portion, N y (N) is the yield axial force.

[0114] From equations (20) and (22) above, the uniformly distributed load w (N / mm) due to the pressure of the concrete 13 when the corner weld 12 of the welded box section member 10 yields is given by equation (22) below.

[0115]

number

[0116] Furthermore, from equations (21) and (23) above, the uniformly distributed load w (N / mm) due to the pressure of the concrete 13 when the widthwise center position of the welded assembled box-shaped cross section member 10 yields is as shown in equation (25) below.

[0117]

number

[0118] Furthermore, the relationship between the uniformly distributed load w (N / mm) due to the pressure of the concrete 13 and the maximum pouring height h (mm) was investigated. According to Non-Patent Literature 3, it has been confirmed that the uniformly distributed load w (N / mm) due to the pressure of the concrete 13 is approximately 1.3 times the hydraulic pressure if the concrete 13 were considered to be a complete liquid. However, since it is difficult to accurately evaluate the uniformly distributed load w (N / mm) due to the pressure of the concrete 13, it was decided to express it using a safety factor S (dimensionless). As shown in Figure 1(a), assuming that the uniformly distributed load w (N / mm) due to the pressure of the concrete 13 is triangularly distributed in the height direction of the welded assembled box-shaped cross section member 10, this uniformly distributed load w (N / mm) is given by equation (24) below.

[0119] w = Shρg ……(26) However, in equation (26) above, S (dimensionless) is the safety factor, and ρ (kg / mm 3 ) is the density of concrete 13, g(mm / s 2 ) is the acceleration due to gravity.

[0120] From equations (18), (24), (25), and (26) above, the maximum concrete placement height h (mm) is as shown in equations (4) to (7) above.

[0121] Then, concrete 13 is poured into the welded box-shaped cross-sectional member 10 at a height H (mm) that is less than or equal to the maximum pouring height h (mm) calculated by the design method for concrete-filled welded box-shaped cross-sectional member described above, thereby manufacturing the concrete-filled welded box-shaped cross-sectional member 1. This realizes the manufacturing method for the concrete-filled welded box-shaped cross-sectional member of this embodiment.

[0122] Furthermore, in the concrete-filled welded box-shaped cross section member 1 of this embodiment, the pouring height H (mm) of the concrete 13 poured inside the welded box-shaped cross section member 10 is set to the following dimensions. That is, as described in the design method for the concrete-filled welded box-shaped cross section member above, the deformation and stress generated in the cross section due to the pressure of the concrete 13 are calculated using a cross section model in which the corners of the cross section of the welded box-shaped cross section member 10 are used as rotating springs and the flat plate portion of the same cross section is used as a bending elastic beam. The pouring height H (mm) of the concrete 13 is set so that the calculated deformation is less than the allowable deformation of the cross section of the welded box-shaped cross section member 10, and the calculated stress is less than the allowable stress of the cross section of the welded box-shaped cross section member 10. [Examples]

[0123] The design method and manufacturing method for the concrete-filled, welded, assembled box-shaped cross-sectional member of the present invention, as well as embodiments of the concrete-filled, welded, assembled box-shaped cross-sectional member, are described below.

[0124] Figures 5(a) and 5(b) show the bending stiffness K of the bending elastic beam 22, calculated using equations (1) and (2) above. m (N·mm 2 The results are shown in comparison with the analytical values ​​for the finite element analysis model shown in Figure 4 and the calculated values ​​from Non-Patent Document 2. Figure 5(b) is an enlarged view of the lower left portion of Figure 5(a).

[0125] As shown in Figures 5(a) and 5(b), the calculated values ​​from Non-Patent Literature 2 were generally overly conservative, and depending on the parameter values, they were more than 20% more conservative than the analytical values ​​obtained by the finite element method. In contrast, the calculated values ​​according to the present invention were found to have an error within ±10% of the analytical values ​​obtained by the finite element method, demonstrating a good correspondence.

[0126] Furthermore, Figures 6(a) and 6(b) show the maximum concrete pouring height h (mm) of the concrete 13 calculated by the design method for concrete-filled welded assembled box-shaped cross section members of the present invention.

[0127] In Figures 6(a) and 6(b), the ▲ marks represent the amount of deformation v at the widthwise center position of the welded box-shaped cross section member 10, calculated from equations (5) and (7) above. c The concrete pouring height h (mm) is shown as the maximum pouring height when (mm) becomes 1 / 1000 of the width D (mm) of the welded box-shaped cross section member 10. Also, in Figures 6(a) and 6(b), the ■ mark indicates the concrete pouring height h (mm) when the uniformly distributed load w (N / mm) due to the pressure of the concrete 13 becomes half of the pressure of the concrete 13 when the welded box-shaped cross section member 10 yields.

[0128] Figure 6(a) shows the penetration depth t of the corner weld 12. w The results are shown when the ratio tw / t between (mm) and plate thickness t (mm) is 1.0. Also, Figure 6(b) shows the ratio t w The results for the case where / t is 0.5 are shown. In the graphs in Figures 6(a) and 6(b), the horizontal axis (D-2t) / t represents the width-to-thickness ratio of the skin plate 11 of the welded box-shaped cross section member 10.

[0129] As shown in Figure 6(a), t w When / t=1.0, the calculated maximum concrete pouring height h (mm) of the concrete 13 was approximately 20m, based on the amount of deformation that occurs in the cross section of the welded assembled box-shaped cross section member 10 when (D-2t) / t=25. Also, as shown in Figure 6(b), t w When / t=0.5, the calculated maximum concrete pouring height h(mm) h of the concrete 13 was approximately 8m due to the stress generated in the cross-section of the welded box-shaped cross-section member 10 when D-2t / t=25.

[0130] Furthermore, Figure 7 shows the maximum concrete pouring height h (mm) of the concrete 13 calculated by the design method for the concrete-filled, welded, assembled box-shaped cross section member of the present invention, compared with the calculated value according to Non-Patent Document 2.

[0131] Figure 7 shows the penetration depth t of the corner weld 12. wWhen the ratio of (mm) to plate thickness t (mm) tw / t is 0.5, the amount of deformation v at the center position in the width direction of the welded assembled box-shaped cross section member 10 is... c The concrete pouring height when (mm) is greater than 1 / 100, 5 / 100, and 1 / 1000 of the width D (mm) of the welded box-shaped cross section member 10 is calculated using equations (4) to (7) above and is shown as the maximum pouring height h (mm). The horizontal axis (D-2t) / t of the graph in Figure 7 is the width-to-thickness ratio of the skin plate 11 of the welded box-shaped cross section member 10.

[0132] As shown in Figures 5(a) and 5(b), the calculated values ​​using equations (1) and (2) of the present invention are greater than the calculated values ​​in Non-Patent Document 2 for the bending stiffness K of the bending elastic beam 22. m (N·mm 2 It was confirmed that this can be evaluated with high accuracy. Furthermore, as shown in Figure 7, it was confirmed that the calculated values ​​using equations (4) to (7) of the present invention can calculate the maximum concrete pouring height h (mm) of the concrete 13 with higher accuracy than the calculated values ​​using Non-Patent Document 2. [Explanation of Symbols]

[0133] 1. Concrete-filled, welded, assembled box-shaped cross-sectional member 10 Welded assembly box-shaped cross section member 11 Skin Plates 12-sided weld 13 Concrete 20 Cross-sectional models 21 Rotating springs 22 Bending dead beam 23 Rollers D Width of welded box section member t Plate thickness of welded box-shaped cross section member t w Depth of penetration in corner welds H Concrete pouring height

Claims

1. A design method for a concrete-filled welded box-shaped cross-sectional member, in which concrete is poured inside a welded box-shaped cross-sectional member, the corner welds of which are joined by partial penetration welding, A cross-sectional model is set up in which the corners of the cross-section of the welded assembled box-shaped cross-sectional member are made into rotating springs, and the flat plate portion of the cross-section is made into a bending elastic beam. The deformation and stress generated in the cross section when the pressure of the concrete poured inside the welded box-shaped cross section member acts on the cross section are calculated using the cross section model. A design method for a concrete-filled, welded, box-shaped cross section member, wherein the maximum concrete pouring height is calculated such that the calculated deformation amount is less than the allowable deformation amount of the cross section, and the calculated stress is less than the allowable stress of the cross section.

2. Bending stiffness K of the bending elastic beam in the cross-sectional model m (N・mm 2 ) is given by the following equation (1) [Math 1] A method for designing a concrete-filled welded box-shaped cross-sectional member according to claim 1, wherein the value satisfies the requirements. However, in equation (1) above, w (N / mm) 2 ) is the pressure applied to the flat plate portion when the pressure of the concrete poured inside the welded box-shaped cross section member acts on the cross section, D (mm) is the width of the welded box-shaped cross-sectional member. t (mm) is the plate thickness of the welded box-shaped cross section member. t w (mm) is the penetration depth of the corner weld, E (N / mm) 2 ) is the Young's modulus of the steel material constituting the flat plate portion, I (mm) 4 ) is the second moment of area of ​​the flat plate portion, C m (Dimensionless) is given by equation (2) below. [Math 2] The coefficient calculated by [the above], where a, b, and c in the above formula (2) are respectively the ratio D / t of the width D (mm) to the plate thickness t (mm) of the welded and assembled box-shaped cross-sectional member, obtained by conducting experiments or numerical analysis on the welded and assembled box-shaped cross-sectional member, and the ratio t w (mm) to the plate thickness t (mm), which is a parameter determined by performing multiple regression analysis on a data group including t w / t.

3. The design method for a concrete-filled welded box-shaped cross section member according to claim 2, wherein the values ​​of the parameters a, b, and c are set within the ranges of 0.020 ≤ a ≤ 0.050, 0.010 ≤ b ≤ 0.015, and 0.60 ≤ c ≤ 0.80, respectively.

4. The design method for a concrete-filled welded box-shaped cross section member according to claim 2, wherein the values ​​of the parameters a, b, and c are set to a = 0.029, b = 0.012, and c = 0.72, respectively.

5. The aforementioned maximum driving height h (mm) is given by the following formula (3) [Math 3] A design method for a concrete-filled, welded, box-shaped cross-sectional member according to any one of claims 1 to 4, calculated by the method described above. However, in equation (3) above, S 1 (Dimensionless) is the safety factor, D (mm) is the width of the welded box-shaped cross-sectional member. t (mm) is the plate thickness of the welded box-shaped cross section member. E (N / mm) 2 ) is the Young's modulus of the steel material constituting the flat plate portion, v c (mm) is the allowable deformation amount at the center position in the width direction of the welded assembly box-shaped cross section member. ρ (kg / mm) 2 ) is the density of concrete, g (mm / s) 2 ) is the acceleration due to gravity, C m (Dimensionless) is given by equation (2) below. [Math 4] The coefficient is calculated by the above equation (2), where a, b, and c are the ratio D / t of the width D (mm) to the plate thickness t (mm) of the welded box-shaped cross section member, and the penetration depth t of the corner weld, respectively, obtained by conducting experiments or numerical analysis on the welded box-shaped cross section member. w The ratio of (mm) to plate thickness t (mm) w This parameter is determined by performing multiple regression analysis on a data set that includes / t.

6. The aforementioned maximum driving height h (mm) is given by the following formula (4) [Math 5] A design method for a concrete-filled, welded, box-shaped cross-sectional member according to any one of claims 1 to 4, calculated by the method described above. However, h in equation (4) above v , h s1 , h s2 These correspond to equations (5) to (7) below. [Math 6] [Number 7] [Number 8] This is a value calculated by the above equations (5) to (7), S 1 ~S 3 (Dimensionless) is the safety factor, D (mm) is the width of the welded box-shaped cross-sectional member. t (mm) is the plate thickness of the welded box-shaped cross section member. t w (mm) is the penetration depth of the corner weld, E (N / mm) 2 ) is the Young's modulus of the steel material constituting the flat plate portion, v c (mm) is the allowable deformation amount at the center position in the width direction of the welded assembly box-shaped cross section member. σ y (N / mm 2 ) is the yield strength of the steel material constituting the flat plate portion, σ yw (N / mm 2 ) is the yield strength of the corner weld, ρ (kg / mm) 2 ) is the density of concrete, g (mm / s) 2 ) is the acceleration due to gravity, C m (Dimensionless) is given by equation (2) below. [Number 9] The coefficient is calculated by the above equation (2), where a, b, and c are the ratio D / t of the width D (mm) to the plate thickness t (mm) of the welded box-shaped cross section member, and the penetration depth t of the corner weld, respectively, obtained by conducting experiments or numerical analysis on the welded box-shaped cross section member. w The ratio of (mm) to plate thickness t (mm) w This parameter is determined by performing multiple regression analysis on a data set that includes / t.

7. A method for manufacturing a concrete-filled welded box-shaped cross-sectional member, wherein concrete is poured into the interior of a welded box-shaped cross-sectional member in which the corner welds are joined by partial penetration welding, A cross-sectional model is set up in which the corners of the cross-section of the welded assembled box-shaped cross-sectional member are made into rotating springs, and the flat plate portion of the cross-section is made into a bending elastic beam. The deformation and stress generated in the cross section when the pressure of the concrete poured inside the welded box-shaped cross section member acts on the cross section are calculated using the cross section model. The maximum concrete pouring height is calculated such that the calculated deformation amount is less than the allowable deformation amount of the cross section, and the calculated stress is less than the allowable stress of the cross section. A method for manufacturing a concrete-filled welded box-shaped cross-sectional member, comprising pouring concrete into the interior of the welded box-shaped cross-sectional member at a height less than or equal to the calculated maximum pouring height, thereby manufacturing the concrete-filled welded box-shaped cross-sectional member.

8. A concrete-filled welded box-shaped cross-sectional member, in which concrete is poured inside a welded box-shaped cross-sectional member, the corner welds of which are joined by partial penetration welding, The height at which the concrete is poured inside the welded box-shaped cross-sectional member is: A concrete-filled, welded box-shaped cross-sectional member, wherein the dimensions are set such that, using a cross-sectional model in which the corners of the cross-section are rotational springs and the flat portions of the cross-section are bending elastic beams, the amount of deformation generated in the cross-section due to the pressure of the concrete is less than the allowable deformation of the cross-section, and the stress generated in the cross-section due to the pressure of the concrete, as calculated using the cross-sectional model, is less than the allowable stress of the cross-section.

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