A monitoring and fixing system for a steel column of a steel reinforced concrete and a construction monitoring method thereof

Abstract

The application discloses a monitoring and fixing system of a steel reinforced concrete steel column and a construction monitoring method thereof, and comprises an inter-column support system, a pre-buried anchor bolt system and a deviation monitoring system; the inter-column support system comprises a plurality of square steel pipes connected between steel columns, and each steel column is connected with at least three adjacent steel columns through the square steel pipes; the pre-buried anchor bolt system comprises a plurality of pre-buried anchor rods which are pre-buried in the bottom of the ground and connected with the column foot of the steel column in the top; and the deviation monitoring system is a strain gauge arranged on each square steel pipe; the square steel pipes connect the column tops into a whole, thereby ensuring the perpendicularity and stability of the steel column, preventing the steel column from deviating during the concrete pouring process and improving the overall stability; the problem that the perpendicularity of the steel column is difficult to control during the construction process of the steel reinforced concrete column is solved; meanwhile, the strain gauge device is arranged on the square steel pipe, the deviation of the steel column before and after the concrete pouring is measured, the perpendicularity or deviation of the steel column beyond the standard range is prevented, and the construction monitoring effect is achieved.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, and in particular to a monitoring and fixing system for steel-concrete composite columns and its construction monitoring method. Background Technology

[0002] Currently, during the concrete pouring process (upper deck concrete or column concrete), the deformation of the base plate or the impact load generated by the pouring vibration can disturb the steel column, causing the steel column to exceed the specifications for verticality or displacement.

[0003] Therefore, ensuring that the steel columns do not exhibit verticality or deviation beyond the standard range is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a monitoring and fixing system for steel-concrete composite columns and its construction monitoring method to solve the problems existing in the prior art, ensure the verticality and stability of the steel columns, prevent the steel columns from shifting during concrete pouring, and improve overall stability; and by measuring the magnitude of the displacement of the steel columns before and after concrete pouring, ensure that the steel columns do not exceed the standard range of verticality or displacement, thus playing a role in construction monitoring.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] This invention provides a monitoring and fixing system for steel-concrete composite columns, including an inter-column support system, a pre-embedded anchor bolt system, and a displacement monitoring system. The inter-column support system includes several square steel pipes connected between the steel columns, and each steel column is connected to at least three adjacent steel columns through the square steel pipes. The pre-embedded anchor bolt system includes several pre-embedded anchor rods with their bottoms embedded underground and their tops connected to the column bases. The displacement monitoring system consists of strain gauges installed on each of the square steel pipes.

[0007] Preferably, the square steel tube is welded to the top of the steel column.

[0008] Preferably, a strain gauge is attached to each of the four walls of the square steel tube, and the distance between each strain gauge and the end of the square steel tube is equal.

[0009] Preferably, each steel column has a set of pre-embedded anchor rods at its bottom. The number of pre-embedded anchor rods in each set is equal to the number of bolt holes on the column base. Each pre-embedded anchor rod in each set is supported and fixed by a reinforcement device. The reinforcement device includes an upper annular positioning plate, a lower annular positioning plate, and a channel steel bracket. The upper and lower annular positioning plates are provided with fixing holes, and the pre-embedded anchor rods are inserted into the fixing holes. The pre-embedded anchor rods at the bottom of the upper annular positioning plate are... Nuts are connected to the anchor rods; multiple channel steel supports are provided and circumferentially distributed around the outer periphery of the lower annular positioning plate; upper channel steel support plates and lower channel steel support plates are respectively provided at the top and bottom of the channel steel supports; multiple slots are provided on the outer periphery of the lower annular positioning plate to engage with each of the channel steel supports; the upper channel steel support plates are welded to the bottom of the upper annular positioning plate; the top of the upper annular positioning plate is welded and fixed to the upper layer of reinforcing bars of the raft foundation; and each of the lower channel steel support plates is welded to the top of the lower layer of reinforcing bars of the raft foundation.

[0010] Preferably, the pre-embedded anchor rod is welded to the upper annular positioning plate and the lower annular positioning plate.

[0011] Preferably, diagonal braces connect the upper channel steel support plate and the lower channel steel support plate of two adjacent channel steel supports.

[0012] Based on the above-mentioned monitoring and fixing system for steel-concrete composite columns, this invention also provides a construction monitoring method for the monitoring and fixing system for steel-concrete composite columns, comprising the following steps:

[0013] 1) Construction preparation:

[0014] Based on the actual site conditions, a component processing and transportation plan was developed, along with a component arrival and inspection procedure, a division of the construction area, and determination of crane positions.

[0015] 2) Install the pre-embedded anchor bolt system:

[0016] During the pre-embedded anchor installation process, an upper ring positioning plate, a lower ring positioning plate, and a channel steel bracket are used to fix the pre-embedded anchor. The upper ring positioning plate and the lower ring positioning plate are welded and fixed to the bottom plate surface layer and the bottom layer of steel reinforcement. Support plates are welded to both ends of the channel steel, and an opening is made in the middle according to the thickness of the lower ring positioning plate. Channel steel brackets are evenly distributed around the outer periphery of the lower ring positioning plate. The lower ring positioning plate is inserted into the opening of the channel steel, and the support plate at the top of the channel steel bracket is welded to the upper ring positioning plate.

[0017] 3) Steel column installation and reinforcement:

[0018] Before installing the steel columns, the longitudinal and transverse positioning axes of the building and the hoisting reference lines of the steel columns should be marked on the steel column foundation as the basis for the alignment and correction of the steel columns. The pre-embedded anchor rods should be checked again to ensure that the pre-embedded anchor rods correspond to the bolt holes on the column feet of the steel columns, so as to ensure the smooth installation of the steel columns.

[0019] After the steel column is installed in place, adjust the steel column in the following order: first adjust the elevation, then adjust the displacement, and finally adjust the verticality. After the adjustment is completed, tighten the column base bolts to fix it.

[0020] 4) Measure the distance between the steel columns;

[0021] Precisely measure the distance between the bases of the steel columns, accurate to the millimeter, and record the distance.

[0022] 5) Cut a square steel tube of the same length as the distance between the base of the steel column and attach strain gauges to all four sides of the square steel tube at the same position.

[0023] 6) The cut square steel pipes are lifted by a crane to the top of the upper steel column for welding, so that the two steel columns are connected and reinforced by the square steel pipes. Each steel column is connected to at least 3 steel columns, and all steel columns are connected into a whole by the square steel pipes.

[0024] 7) Identify the square steel pipe connected to one of the steel columns as the #0 square steel pipe, measure and record the angles between all the square steel pipes connected to the column and the #0 square steel pipe;

[0025] 8) Measure the strain value of the strain gauge on the square steel tube for the first time and record the data;

[0026] 9) After the foundation slab concrete is poured and vibrated, pour the column concrete. When pouring, the material should be poured evenly, and care should be taken to avoid touching the steel columns during vibration.

[0027] 10) After the concrete is poured to the design elevation, measure the strain value of the strain gauge on the square steel pipe in a timely manner and record the data;

[0028] 11) Remove the square steel pipe;

[0029] 12) Employ construction monitoring and calculation methods, and use pre-designed software to calculate the offset of the top of the steel column;

[0030] 13) If the offset is too large and exceeds the standard range, the deviation should be corrected in time with a chain hoist or jack before the concrete sets.

[0031] 14) Construction completed.

[0032] The construction monitoring calculation method is as follows:

[0033] α i Let be the angle between square steel pipe i and the x-axis;

[0034] l i The length of square steel pipe number i;

[0035] F i Let i be the axial force of the square steel pipe.

[0036] ξ 1i The initial measurement value ξ for square steel pipe No. i 1i1 ξ 1i2 ξ 1i3 and ξ 1i4 The average value;

[0037] ξ 2i ξ is the secondary measurement value of square steel pipe No. i. 2i1 ξ 2i2 ξ 2i3 and ξ 2i4 The average value;

[0038] F i =(ξ 2i -ξ 1i E1A1

[0039] E1 is the elastic modulus of the square steel tube;

[0040] A1 is the cross-sectional area of ​​the square steel tube;

[0041] n is the number of square steel pipes connected to the central steel column;

[0042] α is F R The included angle;

[0043] F R For F i The combined force;

[0044]

[0045]

[0046]

[0047]

[0048] Then according to F Rx and F Ry Sign judgment F R The direction;

[0049] The steel column is equivalent to a cantilever beam;

[0050] The formula for calculating the displacement of a free end under concentrated load is:

[0051]

[0052] H is the height of the steel column;

[0053] Δ represents the horizontal offset of the top of the steel column;

[0054] E is the elastic modulus of the steel column;

[0055] I is the moment of inertia of the steel column.

[0056] The present invention achieves the following beneficial technical effects compared to the prior art:

[0057] The present invention provides a monitoring and fixing system and construction monitoring method for steel-concrete composite columns. By connecting the tops of the columns into a unified whole using square steel pipes, the verticality and stability of the steel columns are ensured, preventing displacement during concrete pouring and improving overall stability. This solves the problem of difficulty in controlling the verticality of steel-concrete composite columns during construction. Simultaneously, strain gauge devices are installed on the square steel pipes to measure the displacement of the steel columns before and after concrete pouring, ensuring that the verticality or displacement of the steel columns does not exceed the standard range, thus serving as a construction monitoring function. Attached Figure Description

[0058] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other adjacent drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 This is a schematic diagram of the monitoring and fixing system for the medium-sized steel-concrete composite column of the present invention;

[0060] Figure 2 This is a partial structural schematic diagram of the steel pipe in this invention;

[0061] Figure 3 This is an assembly diagram of the steel column and pre-embedded anchor bolt system in this invention;

[0062] Figure 4 This is a schematic diagram of the pre-embedded anchor system in this invention;

[0063] Figure 5 This is a partial structural diagram of the pre-embedded anchor bolt system in this invention;

[0064] In the diagram: 1-steel column, 2-square steel pipe, 3-steel column base, 4-strain gauge, 5-embedded anchor rod, 6-upper ring positioning plate, 7-lower ring positioning plate, 8-channel steel bracket, 9-upper channel steel support plate, 10-lower channel steel support plate, 11-upper layer reinforcement of raft slab, 12-lower layer reinforcement of raft slab, 13-nut, 14-diagonal brace. Detailed Implementation

[0065] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other adjacent embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0066] The purpose of this invention is to provide a monitoring and fixing system for steel-concrete composite columns and a construction monitoring method thereof, so as to solve the problems existing in the prior art.

[0067] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0068] The monitoring and fixing system for the steel-concrete composite columns in this embodiment, such as... Figures 1-5 As shown, it includes an inter-column support system, a pre-embedded anchor bolt system, and an offset monitoring system. The inter-column support system includes several square steel pipes 2 connected between each steel column 1. Each steel column 1 is connected to at least three adjacent steel columns 1 through the square steel pipes 2. The square steel pipes 2 are welded to the top of the steel column 1. The pre-embedded anchor bolt system includes several pre-embedded anchor rods that are pre-embedded at the bottom underground and connected to the column base 3 of the steel column at the top. The offset monitoring system consists of strain gauges 4 installed on each of the four square steel pipes 2. Each strain gauge 4 is attached to one of the four walls of the square steel pipe 2, and the distance between each strain gauge 4 and the end of the square steel pipe 2 is equal.

[0069] In this specific embodiment, a set of pre-embedded anchor rods is provided at the bottom of each steel column 1. The number of pre-embedded anchor rods 5 in each set is equal to the number of bolt holes on the column base 3. Each pre-embedded anchor rod 5 in each set is supported and fixed by a reinforcement device. The reinforcement device includes an upper annular positioning plate 6, a lower annular positioning plate 7, and a channel steel bracket 8. Fixing holes are provided on the upper annular positioning plate 6 and the lower annular positioning plate 7. The pre-embedded anchor rods 5 are inserted into the fixing holes and welded and fixed. The pre-embedded anchor rods 5 at the bottom of the upper annular positioning plate 6 are also fixed. Nuts 13 are connected to the anchor rods 5; multiple channel steel supports 8 are provided and distributed circumferentially around the outer periphery of the lower annular positioning plate 7. Upper channel steel support plates 9 and lower channel steel support plates 10 are respectively provided at the top and bottom of the channel steel supports 8. Multiple slots are provided on the outer periphery of the lower annular positioning plate 7 to engage with each channel steel support 8. The upper channel steel support plates 9 are welded to the bottom of the upper annular positioning plate 6; the top of the upper annular positioning plate 6 is welded and fixed to the upper layer of reinforcing bars of the raft foundation, and each lower channel steel support plate 10 is welded to the top of the lower layer of reinforcing bars of the raft foundation. Both the upper channel steel support plates 9 and lower channel steel support plates 10 are channel steel structures and are welded and fixed to the channel steel supports 8. Diagonal braces 14 connect the upper channel steel support plates 9 and lower channel steel support plates 10 of two adjacent channel steel supports 8.

[0070] Based on the above-mentioned monitoring and fixing system for steel-concrete composite columns, this embodiment also provides a construction monitoring method for the monitoring and fixing system for steel-concrete composite columns, including the following steps:

[0071] 1) Construction preparation:

[0072] Based on the actual site conditions, a component processing and transportation plan was developed, along with a component arrival and inspection procedure, a division of the construction area, and determination of crane positions.

[0073] 2) Install the pre-embedded anchor bolt system:

[0074] During the pre-embedded installation of the anchor rod 5, the upper ring positioning plate 6, the lower ring positioning plate 7, and the channel steel bracket 8 are used to fix the anchor rod 5. The upper ring positioning plate 6 and the lower ring positioning plate 7 are welded and fixed to the bottom plate surface layer and the bottom layer steel reinforcement. The support plates 9 are welded to both ends of the channel steel. The middle part is opened according to the thickness of the lower ring positioning plate 7. The channel steel bracket 8 is evenly distributed around the outer periphery of the lower ring positioning plate 7. The lower ring positioning plate 7 is inserted into the opening of the channel steel. The support plate 9 at the top of the channel steel bracket 8 is welded to the upper ring positioning plate 6 to fix and support the pre-embedded anchor rod.

[0075] 3) Installation and reinforcement of steel column 1:

[0076] Before installing steel column 1, the longitudinal and transverse positioning axes of the building and the hoisting reference line of steel column 1 should be marked on the steel column foundation as the basis for the alignment and correction of steel column 1. The pre-embedded anchor rods should be checked again to ensure that the pre-embedded anchor rods correspond to the bolt holes on the steel column base 3, so as to ensure the smooth installation of steel column 1.

[0077] After steel column 1 is installed in place, adjust steel column 1 in the following order: first adjust the elevation, then adjust the displacement, and finally adjust the verticality. After the adjustment is completed, tighten the bolts of steel column base 3 to fix it.

[0078] 4) Measure the distance between the steel columns 1;

[0079] Precisely measure the distance between the bases 3 of the steel columns, accurate to the millimeter, and record the distance l. i .

[0080] 5) Cut the distance l between the steel column base 3 and the column base. i Square steel tubes 2 of equal length, and strain gauges 4 are attached to all four sides of the square steel tubes 2 at the same position;

[0081] 6) The cut square steel pipe 2 is lifted to the top of the upper steel column 1 by a crane and welded so that the two steel columns 1 are connected and reinforced by the square steel pipe 2. Each steel column 1 is connected to at least 3 steel columns 1, and all steel columns 1 are connected into a whole by the square steel pipe 2.

[0082] 7) Identify a square steel pipe 2 connected to one of the steel columns 1 as a #0 square steel pipe, and measure the angle α between all the square steel pipes 2 connected to that steel column 1 and the #0 square steel pipe. i (Looking down counterclockwise), and record it;

[0083] 8) Measure the strain value of strain gauge 4 on square steel pipe 2 for the first time and record the data. For example, a set of strains of a certain square steel pipe 2 is ξ. 1i1 ξ 1i2 ξ 1i3 and ξ 1i4 ;

[0084] 9) After the foundation slab concrete is poured and vibrated, pour the column concrete. When pouring, pour the material evenly and take care to avoid touching the steel column 1 during vibration.

[0085] 10) After the concrete is poured to the design elevation, promptly measure the strain value of strain gauge 4 on the square steel pipe 2 and record the data. For example, a set of strains of a certain square steel pipe 2 is ξ. 2i1 ξ 2i2 ξ 2i3 and ξ 2i4 ;

[0086] 11) Remove square steel pipe 2;

[0087] 12) Using the construction monitoring calculation method described below, the offset Δ of the top of steel column 1 is calculated using the designed software;

[0088] 13) If the offset Δ is too large and exceeds the standard range, the deviation should be corrected in time with a chain hoist or jack before the concrete sets.

[0089] 14) Construction completed.

[0090] The construction monitoring calculation method is as follows:

[0091] α i Let be the angle between square steel pipe 2 (i) and the x-axis;

[0092] l i The length of square steel pipe 2 is given by number i.

[0093] F i Let i be the axial force of square steel pipe 2.

[0094] ξ 1i Let ξ be the initial measurement value of square steel pipe 2 of type i. 1i1 ξ 1i2 ξ 1i3 and ξ 1i4 The average value;

[0095] ξ 2i ξ is the secondary measurement value of square steel pipe 2 of type i. 2i1 ξ2i2 ξ 2i3 and ξ 2i4 The average value;

[0096] F i =(ξ 2i -ξ 1i E1A1

[0097] E1 is the elastic modulus of square steel tube 2;

[0098] A1 is the cross-sectional area of ​​square steel pipe 2;

[0099] n is the number of square steel pipes 2 connected to the central steel column 1;

[0100] α is F R The included angle;

[0101] F R For F i The combined force;

[0102]

[0103]

[0104]

[0105]

[0106] Then according to F Rx and F Ry Sign judgment F R The direction;

[0107] Steel column 1 is equivalent to a cantilever beam;

[0108] The formula for calculating the displacement of a free end under concentrated load is:

[0109]

[0110] H is the height of steel column 1;

[0111] Δ is the horizontal offset of the top of steel column 1;

[0112] E is the elastic modulus of steel column 1;

[0113] I is the moment of inertia of steel column 1.

[0114] The displacement of the steel column is caused by the deformation of the base plate or the impact load during the concrete pouring process. The static load of the concrete has a very small effect on the steel column and can be ignored.

[0115] This invention has illustrated its principles and implementation methods using specific examples. The descriptions of these embodiments are merely illustrative of the method and its core ideas; furthermore, those skilled in the art will recognize that modifications may be made to the specific implementation methods and application scope based on the principles of this invention. Therefore, the content of this specification should not be construed as limiting the invention.

Claims

1. A monitoring and fixing system for a steel column of a composite steel column, characterized in that: It comprises an inter-column support system, a pre-buried anchor bolt system and a deviation monitoring system; the inter-column support system comprises a plurality of square steel pipes connected between steel columns, each steel column is connected with at least three adjacent steel columns through the square steel pipes; the pre-buried anchor bolt system comprises a plurality of pre-buried anchor rods pre-buried at the bottom and connected with the steel column foot at the top; the deviation monitoring system is a strain gauge arranged on each square steel pipe; The bottom of each steel column is provided with a group of pre-buried anchor rods, the number of pre-buried anchor rods in each group of pre-buried anchor rods is equal to the number of bolt holes on the steel column foot, and each pre-buried anchor rod in each group of pre-buried anchor rods is supported and fixed by a reinforcing device; the reinforcing device comprises an upper annular positioning plate, a lower annular positioning plate and a channel steel support, the upper annular positioning plate and the lower annular positioning plate are provided with fixing holes, the pre-buried anchor rods are inserted into the fixing holes, and the pre-buried anchor rods at the bottom of the upper annular positioning plate are connected with nuts; a plurality of channel steel supports are provided and circumferentially distributed on the outer periphery of the lower annular positioning plate, the top and bottom of each channel steel support is respectively provided with an upper channel steel support plate and a lower channel steel support plate, the outer periphery of the lower annular positioning plate is provided with a plurality of notches respectively clamped with each channel steel support, and the upper channel steel support plate is welded to the bottom of the upper annular positioning plate; the top of the upper annular positioning plate is welded and fixed with the upper layer of steel bars of the raft, and each lower channel steel support plate is welded to the top of the lower layer of steel bars of the raft.

2. The monitoring and fixing system of the steel-concrete composite column according to claim 1, characterized in that: The square steel pipe is welded to the top of the steel column.

3. The monitoring and fixing system of the steel-concrete composite column according to claim 1, characterized in that: One strain gauge is attached to each of the four walls of the square steel pipe, and each strain gauge is equidistant from the end of the square steel pipe.

4. The monitoring and fixing system of the steel reinforced concrete steel column according to claim 1, characterized in that: The pre-buried anchor rod is welded and connected with the upper annular positioning plate and the lower annular positioning plate.

5. The monitoring and fixing system of the steel-concrete composite column according to claim 1, characterized in that: The upper channel steel support plate and the lower channel steel support plate between the two adjacent channel steel supports are connected with a diagonal brace.

6. A construction monitoring method of a monitoring and fixing system of a steel column of steel reinforced concrete, applied to the monitoring and fixing system of the steel column of steel reinforced concrete according to any one of claims 1-5, characterized in that, It comprises the following steps: 1) construction preparation: According to the actual situation on site, prepare the component processing and transportation scheme, component entry inspection procedure, divide the construction area and determine the crane station; 2) install the pre-buried anchor bolt system: During the pre-buried installation of the pre-buried anchor rod, the pre-buried anchor rod is fixed by the upper annular positioning plate, the lower annular positioning plate and the channel steel support, the upper annular positioning plate and the lower annular positioning plate are welded and fixed with the bottom surface layer and the bottom layer of steel bars, the support plates are welded at both ends of the channel steel, the middle part is opened according to the thickness of the lower annular positioning plate, the channel steel supports are evenly distributed on the outer periphery of the lower annular positioning plate, the lower annular positioning plate is clamped into the opening of the channel steel, and the support plate at the top of the channel steel support is welded with the upper annular positioning plate; 3) steel column installation and reinforcement: Before the installation of the steel column, the longitudinal and transverse positioning axes of the building and the hoisting reference line of the steel column are popped up on the steel column foundation, which are used as the basis for the positioning and correction of the steel column, and the pre-buried anchor rod is checked again to ensure that the pre-buried anchor rod corresponds to the bolt hole on the steel column foot, so as to ensure the smooth installation of the steel column; After the steel column is installed in place, the steel column is adjusted in the order of first adjusting the elevation, then adjusting the displacement and finally adjusting the perpendicularity, and after the adjustment is completed, the steel column foot bolt is tightened and fixed; 4) Measure the distance between the steel columns; Precisely measure the distance between the steel column feet to the mm, and record the distance; 5) Cut the square steel pipe with the same length as the distance between the steel column feet, and paste the strain gauges on the same position of the square steel pipe; 6) Cut the square steel pipe and hoist it to the top of the upper section of the steel column by the crane for welding, so that the two steel columns are connected and reinforced by the square steel pipe. Each steel column is connected to at least three steel columns, and all the steel columns are connected as a whole by the square steel pipe; 7) Determine a certain square steel pipe connected to one of the steel columns as 0# square steel pipe, measure the angle between all square steel pipes connected to the steel column and the 0# square steel pipe, and record it; 8) Measure the strain value of the strain gauges on the square steel pipe for the first time, and record the data; 9) After the bottom plate concrete is poured and vibrated, the column concrete is poured. When pouring, pay attention to uniform feeding and avoid touching the steel column when vibrating; 10) After the concrete is poured to the design elevation, measure the strain value of the strain gauges on the square steel pipe in time, and record the data; 11) Remove the square steel pipe; 12) Use the construction monitoring calculation method to calculate the displacement of the steel column top by using the designed software; 13) If the displacement is too large and exceeds the standard range, correct the deviation in time before the concrete initial setting by using the chain or jack; 14) Construction is completed.

7. The construction monitoring method of the monitoring and fixing system of the steel reinforced concrete steel column according to claim 6, characterized in that: The construction monitoring calculation method in step 12) of claim 6 is as follows: alpha i is the angle between the i-th square steel tube and the x-axis; l i L is the length of the i-th square steel tube; F i P is the axial force of the i-th square steel tube; ξ 1i the average value of the initial measurements of the i-th square steel tube ξ 1i1 , ξ 1i2 , ξ 1i3 and ξ 1i4 ; ξ 2i the average value of the secondary measurement values ξ of the i-th square steel pipe 2i1 , ξ 2i2 , ξ 2i3 , and ξ 2i4 ; E1 is the elastic modulus of the square steel pipe; A1 is the cross-sectional area of the square steel pipe; n is the number of square steel pipes connected to the central steel column; a is F R angle between the vectors F R is F i the resultant force; According to the sign of F Rx and F Ry , the direction of F R is determined. The steel column is equivalent to a cantilever beam; The displacement calculation formula of the free end under the action of concentrated load is: H is the height of the steel column; Δ is the horizontal displacement of the top of the steel column; E is the elastic modulus of the steel column; I is the moment of inertia of the steel column.

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