Method for erecting steel rigid frame structure

Abstract

To provide a method for erecting a steel rigid frame structure, which can easily construct a column base designed by selectively using column base support conditions according to the type of load.SOLUTION: An assembly of the steel rigid frame structure is completed by plumbing a steel column 1 placed on a temporary support 3 and attaching the beam members supported by the shoring, and the bolt holes in a base plate 1a are closed by welding washers 6. An anchor bolt 4 on the side where the base plate 1a rotates downward due to the rotation of the column base caused by jacking down the beam members is temporarily tightened so that a nut 4a comes into contact with the top surface of the washer 6, and the remaining anchor bolts 4 are temporarily tightened with a gap secured between them and the nut 4a so that they do not come into contact with the top surface of the washer 6 on the side where the base plate 1a rotates upward. After the beam members are jacked down and stand on their own as a frame of the steel frame structure, all of the anchor bolts 4 are finally tightened and base mortar 7 is completely filled under the base plate 1a.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method for erecting a steel frame rigid frame. [Background technology]

[0002] When designing the frame and foundation of a steel frame rigid frame structure, it is common to design the frame (column members, beam members) and foundation (piles, footings) assuming that the support conditions of the column base are either rotationally free (hereinafter referred to as pinned) or rotationally restrained (hereinafter referred to as fixed). However, whether the support conditions of the column base are pinned or fixed results in a large difference in the deformation and stress in the frame and foundation, which also affects the cost of the structure.

[0003] Even if the steel moment-frame structure has the same floor height, column spacing, cross-sectional size of columns and beams, and the same loading conditions, the deformation of the structure and the column base reaction force will differ depending on the support conditions of the column base, and qualitatively there are the following differences: (1) In the case of pin (free rotation) support a) Because the column base rotates, the deflection of the beams tends to be large under vertical loads, and the horizontal deformation of the frame (inter-story deformation) tends to be large under horizontal loads. (b) Regarding column base reaction forces, only vertical and horizontal reaction forces occur for any type of load, and no column base fixing moment occurs.

[0004] (2) Fixed (rotation restricted) support a) Since the rotation of the column base is restricted, the deflection of the beam is small under vertical load, and the horizontal deformation of the frame (inter-story deformation) tends to be small under horizontal load. (b) In addition to vertical and horizontal reaction forces, a corresponding column base fixing moment is generated for any type of load.

[0005] In reality, the base of an exposed base type column is fixed only by anchor bolts, and when a base fixing moment occurs at the base, the anchor bolts stretch, so the column is not completely fixed. However, here we will broadly refer to the state in which rotation is restricted as "fixed."

[0006] When designing the frame and foundation of a steel frame rigid frame structure, fixing to the column base is advantageous when minimizing deformation of the frame, but on the other hand, a correspondingly large column base fixing moment acts on the foundation, which requires larger dimensions for the piles and footings, resulting in increased costs. This effect is particularly significant in places with poor ground conditions.

[0007] On the other hand, pin support is advantageous in designing the foundation because no column base fixing moment is generated, but the cross-sectional size of the columns and beams must be increased in order to suppress the deformation of the frame, which increases the cost of the frame.

[0008] As mentioned above, the stress and deformation of a steel moment-resistant frame is greatly affected by the degree of fixation (pinned or fixed) of the column base, which changes the balance between the size and cost of the components of the frame and foundation. Therefore, if it were possible to use different support conditions for the column base depending on the type of load that causes different deformations and stress states in the steel moment-resistant frame, the design of the structure could become more rational.

[0009] The bending moment distribution of a steel moment frame when the support conditions of the column base (pin support, fixed support) and the load type (fixed load, earthquake load) are combined is shown schematically in Figure 1. Figure 1(a) shows that when the column is fixed against the dead load (DL) and also fixed against the earthquake load (EQ) in the direction of the arrow, the maximum bending moment of the member under the combined load (DL+EQ) is a M T , at the base of the column a M B This indicates that

[0010] Figure 1(b) shows that when the column is pin-supported against the dead load (DL) and also pin-supported against the earthquake load (EQ) in the direction of the arrow, the maximum bending moment of the member under the combined load (DL+EQ) is b M T , at the base of the column b M B This indicates that

[0011] Figure 1(c) shows that when the column is pin-supported against the dead load (DL) and fixedly supported against the earthquake load (EQ) in the direction of the arrow, the maximum bending moment of the member under the combined load (DL+EQ) is c M T , at the base of the column c M B This indicates that

[0012] Table 1 shows an example of calculations for a steel frame rigid frame, showing the ratios of the column head and column base bending moment M, column base shear force Q, and column base axial force N when the column base support conditions are changed between fixed load and earthquake. In the calculation example, the frame model and design conditions shown in Figure 6 were assumed, and the following three combinations were compared. (Case a) Fixed support during both fixed load and earthquake. (Case b) Pin support during both fixed load and earthquake. (Case c) Pin support during fixed load, fixed support during earthquake.

[0013] [Table 1]

[0014] Calculation example 1 is a case where the weight of the roof and wall sections is included as fixed load, and the results show that the stresses in the columns (M, Q, N) are compared as shown above. Capital M T Comparison of: c < a < b M for column base B Comparison of: b < c < a Column base Q B Comparison: c = b < a Column base N B Comparison: c = a < b(maximum value) From this result, the combination of case c is B It can be seen that the stress is minimum except for

[0015] In case b, the bending moment M Bis minimum (=0), which is advantageous in terms of the load acting on the base, but on the other hand, the bending moment M T The ratio of b / c to case c is large at b / c=1.36, and the size of the columns and beams will be larger, so it is necessary to compare the cost reduction effect of reducing the load acting on the foundation with the increased cost of the steel frame.If the ground conditions are poor, the column base support conditions of case b may be more advantageous.

[0016] Allowing a certain amount of load to the base, the bending moment M T If you want to suppress the magnitude of the bending moment M of the column base in case c, B The ratio c / a is 0.46, so it can be said that this is significantly more advantageous than case a.

[0017] Calculation example 1 was a case where the weight of the entire roof and wall sections was included as fixed load, but in the construction procedure for a steel frame rigid frame, when the column bases are in a pin-supported state during construction and all fixed loads, including finishes other than the steel frame, have been attached, jacking down (i.e., releasing the support for the beam members by the shoring) is difficult to coordinate with the installation process for finishing, etc., and is therefore not practical.

[0018] In this case, it may be possible to limit the range of dead loads to be jacked down to steel frames. Therefore, in calculation example 2, only in case c, the weight of steel frames (DL1) in the dead load (DL) was assumed to be 50% of that in calculation example 1, and the stresses in the three cases were compared. The results are shown in Table 2.

[0019] [Table 2]

[0020] The results of calculation example 2 show that the magnitude relationship of each stress is as follows. The shear force Q of the column base is B The only difference from calculation example 1 is Capital M T Comparison of: c < a < b M for column base BComparison of: b < c < a Column base Q B Comparison of: b < c < a Column base N B Comparison: c = a < b(maximum value) The shear force of the column base Q B The ratio c / b between case c and case b was 1.21 because 50% of the fixed load (DL2: other than steel frame) was fixedly supported, and the shear force of the column under fixed load was greater than when it was pin-supported.

[0021] Bending moment M of column base B The ratio of case c to case a is c / a = 0.73, which is smaller than that of calculation example 1 (c / a = 0.46) and the bending moment M B Although the reduction rate is small, the effect is still considerable.

[0022] Also, the bending moment M T Looking at the ratio of case b to case c, b / c=1.27, it can be seen that there is not much difference from the ratio of b / c=1.36 in calculation example 1.

[0023] To summarize the above, if the column base support condition is pin support (case b) for all loads (here, dead loads and earthquake loads), the bending moment at the column base will be minimal (=0), which is advantageous for the foundation, but on the other hand, the bending moments at the columns and beams will become quite large, which may be disadvantageous in terms of overall cost.On the other hand, if the column base support condition is fixed support (case a) for all loads, the bending moment at the column base acting on the foundation will be very large (a / c = 2.17 (calculation example 1), 1.37 (calculation example 2)), and moreover the bending moment at the column head will not be much smaller than in case b (a / b = 0.84).

[0024] However, in case c, the bending moment acting on the base of the column is significantly smaller than in case a (c / a = 0.46 (calculation example 1), 0.73 (calculation example 2)), and the bending moment on the column head is significantly reduced compared to case b (c / b = 0.74 (calculation example 1), 0.79 (calculation example 2)).

[0025] As can be seen from the comparison between Calculation Example 1 and Calculation Example 2, the greater the fixed load that is jacked down using pin support at the column base, the greater the effect of reducing stress at the column head and column base by selectively using pin support and fixed support. In addition to fixed loads and earthquakes, other load types include snowfall and wind, but it goes without saying that the column base support conditions when these loads act are fixed support.

[0026] An example of a prior art document relating to reducing the reaction force acting on the column base of a steel frame moment frame is Patent Document 1. The invention described in Patent Document 1 is a support column structure for a truss beam, characterized in that in a roof frame made of a truss beam, a flexible section made of a flexible plate whose thickness direction coincides with the span direction of the truss beam is formed at the column head or column base of the support column supporting the truss beam, with the flexible section extending for a predetermined length in the material axis direction of the support column.

[0027] Therefore, when the truss beam bends due to a vertical load such as its own weight, the flexible plate of the flexible section formed at the head or base of the support column bends in response to the tilt of the support column or the rotation of the end of the truss beam, and the flexible section rotates just like a pin joint, facilitating the tilt of the support column, thereby significantly reducing the bending moment generated in the support column. As a result, the thrust generated at the base of the support column is extremely small.

[0028] Furthermore, the invention described in Patent Document 2 discloses a sliding construction method for a portal frame structure in which the joint between the top of the columns of the portal frame partial frame and the roof section is achieved by connecting only either the upper or lower chord at both ends of the roof girder (truss beam), leaving the joint in a state in which rotation in the vertical plane at both ends of the roof section is permitted to a certain extent, and while both ends of the roof girder are left in a pin-jointed state, the jacks of the jack-equipped shoring supporting the roof section of the portal frame partial frame are loosened to release the temporary support of the roof section by the shoring, and then the unconnected parts (lower or upper chord) at both ends of the roof girder are connected to the columns, thereby rigidly joining the top of the columns of the portal frame partial frame and the roof section and completing the portal frame structure.

[0029] The invention described in Patent Document 3 discloses a foundation structure for a steel frame comprising a plurality of steel-framed rigid frame structures extending in the span direction and a plurality of steel-framed braced frames extending in the longitudinal direction, the rigid frame structures being spaced apart in the longitudinal direction, the braced frames being formed by a plurality of columns constituting the rigid frame structure and beams and braces connecting the columns, a base plate attached to the lower ends of the columns, and a reinforced concrete foundation and the base plate connected via anchor bolts. The foundation is cylindrical, and the foundation and the base plate are pin-joined in the span direction via axial force transmission members.

[0030] The invention described in Patent Document 4 discloses a support structure for a column member of a rigid frame structure, in which the upper and lower ends of the column member are supported by first and second beam members, the first and second beam members having curved first and second convex support portions on the support surfaces of the column member, the column member having first and second concave receiving portions at the upper and lower ends that are rotatable while sliding against the first and second convex support portions, and pin joints are formed between the first convex support portion and the first concave receiving portion, and between the second convex support portion and the second concave receiving portion. [Prior art documents] [Patent documents]

[0031] [Patent Document 1] Patent application No. 2023-042971 [Patent Document 2] Patent No. 6636091 [Patent Document 3] Japanese Patent Publication No. 2021-139149 [Patent Document 4] Japanese Patent Publication No. 2022-163550 Summary of the Invention [Problem to be solved by the invention]

[0032] However, in the invention described in Patent Document 1, while the reaction force acting on the lower structural frame that supports the support columns is reduced, thereby reducing the burden on the lower structural frame, the deflection of the truss beams due to vertical loads such as their own weight increases. Furthermore, since the flexible parts formed at the column heads or column bases of the support columns are allowed to rotate against all loads, when a horizontal earthquake force acts on the roof frame, the inter-layer deformation of the roof frame, including the support columns, increases compared to when the rotation of the flexible parts is restricted.

[0033] In other words, the support conditions of the support columns are the same for all loads, and there is no disclosure or suggestion of using them differently depending on the type of load.

[0034] The invention described in Patent Document 2 is a sliding construction method for rigid frame structures, and does not take into consideration the column bases. Furthermore, the invention described in Patent Document 3 relates to a foundation structure that supports the columns of a frame that includes both a rigid frame and a braced frame, and aims to reduce the size of the foundation with construction that is as inexpensive as possible, but does not take into consideration the support conditions of the column base depending on the type of load. The invention described in Patent Document 4 is for a building, etc., made of a rigid frame, in which the upper and lower ends of column members with small cross sections are supported by beam members in a manner similar to pin support.

[0035] The present invention provides a practical and simple method for constructing a steel frame rigid frame that allows for easy construction of column bases designed based on a design method that suppresses the column base fixing moment to a certain extent by using different support conditions (pinned or fixed) for the column base depending on the type of load. [Means for solving the problem]

[0036] The means of the present invention to solve the above problem is 1) At the installation location of the steel column of the steel frame rigid frame structure, temporary support materials (mortar balls or iron balls) that temporarily support the steel column during construction are installed on the top surface of the foundation where anchor bolts have already been installed, within a certain range including the axis of the steel column. 2) The steel column is placed on the temporary support material with the anchor bolts inserted into the bolt holes opened in the base plate of the column base of the steel column, and is temporarily installed in the predetermined position. 3) The temporarily installed steel column is then plumbed, and the anchor bolts are temporarily tightened to stabilize the steel column.

[0037] 4) After the construction is complete, the beam members are attached to the steel columns while supported by the supports, and the assembly of the steel rigid frame structure is completed. 5) A washer having an outer dimension larger than the diameter of the bolt hole in the base plate is attached to the anchor bolt and the washer is fixed to the base plate to close the bolt hole, or the bolt hole is closed by filling the gap between the bolt hole in the base plate and the anchor bolt with a metal piece shaped to fit the gap.

[0038] 6) The anchor bolts on the side where the base plate rotates downward due to the rotation of the column base caused by the release of support for the beam member by the shoring are temporarily tightened so that the nuts come into contact with the top of the base plate, and the remaining anchor bolts are temporarily tightened with a gap secured between them and the nuts so that they do not come into contact with the top of the base plate on the side where the anchor bolts rotate upward. 7) The support of the beam members by the shoring is released, and the beam members become independent as a steel frame rigid frame structure.

[0039] 8) All of the anchor bolts are fully tightened. 9) The base mortar is completely filled under the base plate. This is a method for erecting a steel frame rigid frame, characterized by including the above steps.

[0040] The present invention also provides a method for erecting a steel frame rigid frame, characterized in that the roof frame of the steel frame rigid frame is composed of diagonal truss beams or diagonal single-member (H-shaped steel, etc.) beams, or is composed of a space truss in which members are assembled three-dimensionally.

[0041] Furthermore, the present invention provides a method for erecting a steel frame rigid frame, in which, among the plurality of installed anchor bolts, at least a pair of anchor bolts ((1) in FIG. 4) are arranged adjacent to each other in a direction perpendicular to the rotation axis of the column base, which are located on a side where the base plate rotates downward due to the rotation of the column base caused by the support being released from the beam member by the shoring. * )) is installed in the gap between the underside of the base plate and the upper surface of the foundation. In principle, the connecting reinforcement material should be installed before the steel column is installed, or at the latest before the jacking down.

[0042] The connecting reinforcement material may have the following forms. 1) At least two through holes for anchor bolts are provided, and the hole diameters are larger than the shaft diameters of the anchor bolts by at least the dimension of the anchor bolt installation error set as a control value. 2) After the anchor bolt is inserted, the gap in the anchor bolt through hole is filled with metal or grout material having a shape that matches the gap between the anchor bolt through hole and the anchor bolt, thereby ensuring tight contact with the anchor bolt. 3) The height of the connecting reinforcement is lower than the height of the gap between the underside of the base plate and the upper surface of the foundation, to the extent that it does not hinder the sinking caused by the downward rotation of the base plate as the column base rotates.

[0043] As described above, by connecting and reinforcing the anchor bolts, which were exposed without being filled with base mortar, in pairs, the section in which the anchor bolts are cantilevered is shortened, thereby improving the bending shear resistance against the horizontal reaction force (hereinafter referred to as thrust force) of the column base generated by jacking down the beam member.

[0044] Since the present invention is a method for erecting a steel frame rigid frame as described above, the column base support conditions for fixed loads such as the frame's own weight are essentially pin support, so the generation of column base fixing moment is minimal and the load on the foundation is reduced.

[0045] Furthermore, after the beam members have been jacked down, the base mortar has been completely filled in and all anchor bolts have been fully tightened, resulting in a fixed (rotation-restrained) support, which prevents deformation of the steel moment frame from loads such as earthquakes and snowfall, and also reduces bending stress in the column and beam members more than in the case of pin support. At this time, a corresponding column base fixing moment acts on the foundation, but its magnitude is smaller than when the beam members are fixedly supported against all loads, since there is no column base fixing moment corresponding to fixed loads such as the frame's own weight. [Effects of the Invention]

[0046] The present invention, which is based on the above means, has the following effects. (1) Even when erecting a steel frame moment frame, the anchor bolts resist the thrust force while allowing the column base to rotate when the beam members are jacked down, so it is easy to essentially make the column base support conditions for fixed loads such as the frame's own weight pin support. At this time, almost no column base fixing moment acts on the foundation. (2) For loads other than the frame's own weight and other fixed loads (earthquakes, snow accumulation, etc.), the column base can be easily fixed (with rotation restraint) by simply tightening the anchor bolts after filling the base mortar. In this case, the column base fixing moment generated in the foundation occurs only for loads other than the frame's own weight and other fixed loads (earthquakes, snow accumulation, etc.).

[0047] (3) As mentioned above, because it is easy to use different column base support conditions depending on the type of load, deformation and stress of the steel moment-retaining frame are suppressed to a certain extent, while the force acting on the foundation is also reduced. This alleviates the uneven load on either the frame or the foundation, allowing for a more rational design of the structure. In other words, because the final column base support condition is fixed (rotation restrained) support, after construction is complete, the deflection of the beams in the frame and inter-story deformation during an earthquake are suppressed, while the column base fixed moment is reduced by the amount equivalent to the fixed load, such as the frame's own weight, so the foundation structure can be designed to be smaller. This also leads to cost reductions for the entire structure.

[0048] (4) The greater the ratio of the fixed load when jacked down in a pin-supported state to the combined load of the fixed load and earthquake load, the greater the effect of reducing the column base fixing moment. This is expected to reduce the cost of the foundation, particularly in buildings such as large-span hangars (see Figure 5), where the weight of the roof structure tends to be heavy.

[0049] (5) When the beam member is jacked down, the base mortar is not completely filled, so the anchor bolt is a cantilevered member having a length at least equal to the thickness of the base mortar. Therefore, even if the resistance to thrust force is insufficient, the cantilevered section can be shortened by attaching a connecting reinforcement to the anchor bolt, and the bending shear resistance to thrust force can be easily increased. [Brief explanation of the drawings]

[0050] [Figure 1]These are explanatory diagrams of the bending moment distribution acting on a steel moment-retaining frame when column base support conditions (pin, fixed) are used in combination for fixed loads and earthquakes. (a) shows the case where both are fixed supports, (b) shows the case where both are pin supports, and (c) shows the case where both are pin supports and fixed supports. [Figure 2] This figure shows the state of a steel rigid frame frame supported by column base pins before (dashed line) and after (solid line) deformation due to a fixed load (distributed load WDL). [Figure 3] FIG. 1 is a flowchart showing the erection procedure of a steel frame rigid frame according to the present invention. [Figure 4] 4A to 4C are diagrams showing the construction state of the column base corresponding to the step numbers in the flowchart of FIG. 3. [Figure 5] FIG. 1 is a perspective view showing an example of a long span rigid frame structure having a diagonal truss roof. [Figure 6] This is a structural model hypothesized to estimate the ratio of the column head and base bending moment M, column base shear force Q, and column base axial force N when the column base support conditions are changed between fixed load and earthquake. DETAILED DESCRIPTION OF THE INVENTION

[0051] An embodiment of the present invention will be described with reference to FIGS. 3 and 4, assuming the column base portion of part A shown in FIG.

[0052] In the flowchart shown in Figure 3, in step (1), at a predetermined position where a column 1 of a steel frame rigid frame structure is to be installed, temporary support materials 3 (mortar balls or iron balls) for temporarily supporting the steel column 1 during construction are installed on the top surface of the foundation part 5 where anchor bolts 4, 4, ... have already been installed, within a certain range including the axis of the steel column 1.

[0053] In step (2), the steel column 1 is temporarily installed in a predetermined position by inserting anchor bolts 4, 4, ... into bolt holes opened in the base plate 1a of the column base of the steel column 1 and placing it on the temporary support material 3. The diameter of the bolt holes in the base plate 1a is opened larger than the shaft diameter of the anchor bolts 4, 4, ... by at least the dimension of the anchor bolt installation error set as a control value. In step (3), the steel column 1 is plumbed to ensure its correct position and verticality, and all anchor bolts 4, 4, . . . are temporarily tightened to stabilize the steel column 1.

[0054] After the steel column 1 has been installed, in step (4), both ends of the beam member 2 are attached to the steel columns 1, 1 while supported by supports (not shown), completing the assembly of the steel rigid frame structure.

[0055] Next, in step (5), washers 6, 6, ... with outer dimensions larger than the bolt hole diameter of base plate 1a are attached to anchor bolts 4, 4, ..., and the washers 6, 6, ... are fixed to base plate 1a by welding, thereby closing the bolt holes in base plate 1a. Alternatively, a method may be used in which metal fittings (commercially available or custom-made) shaped to fit the gaps between the bolt holes in base plate 1a and the anchor bolts 4, 4, ... are inserted to close the gaps.

[0056] In step (6), the anchor bolts 4, 4, ... on the side (outside in Figure 4) where the base plate 1a rotates downward due to the rotation of the column base caused by jacking down the beam member 2 (see part A in Figure 2) are provisionally tightened so that the nuts 4a, 4a, ... come into contact with the top of the base plate 1a (with the fixed washers 6, 6, ... in Figure 4 (6)), and the remaining anchor bolts 4, 4, ... are provisionally tightened with a gap maintained between them and the nuts 4a, 4a, ... so that they do not come into contact with the top of the base plate 1a (with the fixed washers 6, 6, ... in Figure 4 (6)) on the side (inside in Figure 4) where the column base rotates upward.

[0057] In step (7), when the beam member 2 is jacked down, the base of the column 1 rotates in the direction of the circular arrow shown in step (8) of Figure 4, and the steel frame moment frame becomes self-supporting. At this time, secondary members such as purlins and furring strips, or finishing materials attached to them (not shown), may also be attached to the steel frame moment frame to the extent possible. In step (8), all of the anchor bolts 4, 4, . . . are fully tightened while the base plate 1a remains inclined.

[0058] In step (9), the base mortar 7 is completely filled under the base plate 1a. The column bases of the completed steel frame rigid frame are fixed (rotationally restricted), so that the steel frame rigid frame remains fixed at the column bases during earthquakes, snowfall, etc.

[0059] In the above examples, a general planar frame rigid frame has been assumed, but it goes without saying that the above procedure can also be followed to erect a rigid frame whose roof structure is made up of diagonal truss beams (see Figure 5) or diagonal single beams (H-shaped steel, etc.), or a three-dimensional truss frame in which components are assembled three-dimensionally.

[0060] In the case of a steel rigid frame structure with a roof frame of these structural types, such as the one shown in Figure 5, in which the roof frame is made up of diagonal truss beams, the basic rule is to jack down the building when at least the entire frame is assembled.Since the roof frame is already completed, it is also possible to place finishing materials on the roof and then jack down the building.

[0061] On the other hand, with a flat steel frame rigid frame, the entire building frame is not assembled and then jacked down, but rather each structural surface is generally jacked down separately, so it is not practical to place finishing materials etc. before jacking down.

[0062] If finishing materials, etc. can be placed during jacking down, the fixed load to be jacked down will be greater than the weight of the steel frame itself, and as shown in the calculation example above, the stress reduction effect on the column head and column base can be greater by selectively using pin support and fixed support.

[0063] In step (7), jacking down the beam member 2 tilts the column 1 as shown by the solid line in Figure 2, and the rotation of the column base causes the inside of the base plate 1a to lift up. At this time, a thrust force acts on the column base, tending to spread outward, and the anchor bolts 4, 4, ... must resist this force. In this case, when the beam member 2 is jacked down, the gap between the base plate 1a of the column base and the top surface of the foundation 5 has not yet been filled with base mortar 7, so the anchor bolts 4, 4, ... act as cantilevers with a length at least the thickness of the base mortar 7 and are subjected to bending shear forces, which may result in insufficient resistance to the thrust force.

[0064] Therefore, we will introduce a procedure (1) instead of the procedure (1) in Figure 3. * ), among the plurality of anchor bolts 4, 4, ... installed at the installation position of the steel column 1, the side where the base plate 1a rotates downward due to the rotation of the column base (see part A in Figure 2) that occurs when the beam member 2 is jacked down (step (7)) (see part A in Figure 4) * ) are anchor bolts 4, 4, ... located on the "outside" side of the base of the steel column 1, and connecting reinforcements 10, 10 are attached to at least a pair of anchor bolts 4, 4, ... that are arranged adjacent to each other in a direction perpendicular to the rotation axis of the base of the steel column 1 (left and right directions on the paper in Figure 4).

[0065] The effective length over which a pair of anchor bolts 4, 4 connected by the connecting reinforcement 10 are subjected to bending shear force is shortened from the top surface of the connecting reinforcement 10 to the lower end of the washer plate 6, improving resistance to bending shear from the thrust force. Therefore, the pin-supported column base is resistant to the vertical reaction force and horizontal reaction force (thrust force) at the column base when the beam member 2 is jacked down.

[0066] The side where the base plate 1a rotates downward (see Figure 4, step 1) * If the reinforcement is insufficient by simply attaching the connecting reinforcement members 10, 10 to the anchor bolts 4, 4, ... on the "outside" side shown in Figure 4, * ) may also be attached to the anchor bolts 4, 4, ... on the "inside" side (shown in Fig. 1). However, if the anchor bolts 4, 4, ... have sufficient bending shear strength, the connecting reinforcements 10, 10, ... may not be necessary.

[0067] In addition, the gap between the upper surfaces of the connecting reinforcements 10, 10 and the underside of the base plate 1a must be large enough to prevent contact when the outer part of the base plate 1a rotates downward due to jacking down of the beam member 2.

[0068] Incidentally, in the base plate 1a of the inner part that rotates upward, a gap is secured between the nuts 4a, 4a, ... of the anchor bolts 4, 4, ... so that even if the base plate 1a rises up, it will not come into contact with them, and further rising is suppressed. However, if there are no connecting reinforcements 10, 10 under the base plate 1a of the outer part that rotates downward, stoppers 11, 11, ... as shown in Figures 4(6) and (8) may be provided to prevent the base plate 1a from sinking excessively.

[0069] Furthermore, if the temporary support material 3 is a mortar ball, it may collapse before the base mortar 7 is completely filled in, so it is desirable to take some other measures. [Industrial Applicability]

[0070] According to the present invention, in the construction of a steel frame moment resisting frame, the column base support conditions for fixed loads such as the frame's own weight can be essentially pin support, and for loads other than the fixed loads (earthquakes, snow accumulation, etc.), the column base can be fixed (with rotation restraint) for support. This increases the options for designing steel frame moment resisting frames by using different column base support conditions depending on the type of load, and contributes to the provision of more rational structural frames.

[0071] Furthermore, the greater the proportion of the fixed load when jacking down the column base using pin support to the combined load of the fixed load and earthquake load, the greater the effect of reducing the column base fixed moment, which can contribute to reducing the cost of the foundation structure, particularly in buildings such as hangars where the roof frame has a heavy weight between the sidings. [Explanation of symbols]

[0072] 1: Pillar 1a: Base plate 2: Beam 3: Temporary support material 4: Anchor bolt 5:Foundation 6: Washer 7: Base mortar 10: Connecting reinforcement material 11: Stopper

Claims

1. 1) At the installation location of the steel column of the steel frame rigid frame structure, temporary support materials for temporarily supporting the steel column during construction are installed on the top surface of the foundation where anchor bolts have already been installed, within a certain range including the axis of the steel column. 2) The steel column is placed on the temporary support material with the anchor bolts inserted into bolt holes opened in the base plate of the column base of the steel column, and is temporarily installed in a predetermined position. 3) The temporarily installed steel column is then plumbed, and the anchor bolts are temporarily tightened to stabilize the steel column. 4) After the erection is completed, the beam members are attached to the steel columns while supported by the supports, and the assembly of the steel rigid frame structure is completed. 5) A washer having an outer dimension larger than the diameter of the bolt hole in the base plate is attached to the anchor bolt and the washer is fixed to the base plate to close the bolt hole, or the bolt hole is closed by filling the gap between the bolt hole in the base plate and the anchor bolt with a metal piece shaped to fit the gap. 6) The anchor bolts on the side where the base plate rotates downward due to the rotation of the column base caused by the release of support for the beam member by the shoring are temporarily tightened so that the nuts come into contact with the top of the base plate, and the remaining anchor bolts are temporarily tightened with a gap secured between them and the nuts so that they do not come into contact with the top of the base plate on the side where the anchor bolts rotate upward. 7) The support of the beam members by the shoring is released, and the beam members become independent as a steel frame rigid frame structure. 8) All of the anchor bolts are fully tightened. 9) The base mortar is completely filled under the base plate. A method for erecting a steel frame rigid frame, comprising the above steps.

2. 2. A method for erecting a steel frame rigid-frame structure according to claim 1, wherein the roof frame of the steel frame rigid-frame structure is composed of diagonal truss beams or diagonal single-member beams, or is composed of a space truss in which members are assembled three-dimensionally.

3. 3. The method for erecting a steel frame rigid-frame frame according to claim 1 or 2, wherein a connecting reinforcement member for connecting and reinforcing at least a pair of anchor bolts arranged adjacent to each other in a direction perpendicular to the rotation axis of the column base is installed in a gap between the underside of the base plate and the upper surface of the foundation during construction of the column base of the steel frame rigid-frame frame, the anchor bolts being on a side where the base plate rotates downward due to rotation of the column base that occurs when support of the beam member by the shoring is released, and the anchor bolts are arranged adjacent to each other in a direction perpendicular to the rotation axis of the column base.

4. In the method for erecting a steel frame rigid frame according to claim 3, the connecting reinforcement material is 1) At least two through holes for anchor bolts are provided, and the hole diameters are larger than the shaft diameters of the anchor bolts by at least the dimension of the anchor bolt installation error set as a control value. 2) After the anchor bolt is inserted, the gap in the anchor bolt through hole is filled with metal or grout material having a shape that matches the gap between the anchor bolt through hole and the anchor bolt, thereby ensuring tight contact with the anchor bolt. 3) The height of the connecting reinforcement is lower than the height of the gap between the underside of the base plate and the upper surface of the foundation, to the extent that it does not hinder the sinking caused by the downward rotation of the base plate as the column base rotates. A method for erecting a steel frame rigid frame characterized by including the above characteristics.

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