A performance calculation method for single-column steel tube lightning rod

Abstract

The application discloses a kind of single-column steel pipe lightning rod performance calculation method, comprising: obtaining load parameter, and according to load parameter to single-column steel pipe lightning rod, load combination calculation, gravity load calculation, wind load calculation and internal force standard value calculation are carried out;Obtain component parameter, and according to component parameter to single-column steel pipe lightning rod, component strength checking calculation, component deformation checking calculation and component stability checking calculation are carried out;Obtain connection parameter, and according to connection parameter to single-column steel pipe lightning rod, flange bolt strength checking calculation, flange plate strength checking calculation, stiffened plate strength checking calculation and stiffened plate weld checking calculation are carried out;According to the calculation result and checking result, real-time monitoring is carried out to single-column steel pipe lightning rod.The performance parameters of single-column steel pipe lightning rod are comprehensively calculated and monitored by using the application, to ensure the structural safety of lightning rod.

Description

Technical Field

[0001] This invention relates to a power equipment performance calculation technique, and more particularly to a method for calculating the performance of a single-column steel tube lightning rod. Background Technology

[0002] The lightning protection function of substation lightning rods is crucial to the safety of the entire substation and even the entire power system. With the gradual increase in substation voltage levels and the increasing frequency of severe weather such as typhoons in coastal areas, the structural safety and reliability of substation lightning rods has become a key concern for substation civil engineering designers. To ensure the structural safety of substation lightning rods, more in-depth and comprehensive calculations and designs are necessary. However, current design codes and references regarding the calculation and design of substation lightning rods are relatively simplistic and cannot meet the requirements for in-depth calculations and designs.

[0003] Lightning rods for substations can be divided into frame lightning rods and independent lightning rods. Frame lightning rods are fixed to the substation frame or the roof of a building within the substation and do not have a foundation. Independent lightning rods are located directly on the ground and require a foundation.

[0004] Currently, the commonly used structural forms of lightning rods in substations are mainly single-column steel pipe type and lattice steel structure. Due to the advantages of light weight and steel saving, lattice steel structure has been commonly used for independent lightning rods in the past. On the other hand, single-column steel pipe type lightning rod has the advantages of simple processing and manufacturing, quick and convenient construction and installation, and easy assurance of construction quality, and is mostly used for frame lightning rods.

[0005] According to the "Special Anti-Accident Measures for Damage to Substation Equipment and Optimization of Substation Power Supply Configuration during Typhoon 'Rainbow'" document No. 21 of 2016 issued by China Southern Power Grid Equipment, "For newly built substations with a maximum design wind speed exceeding 35m / s, single-column lightning rods should be given priority for independent lightning rods within the substation."

[0006] China Southern Power Grid's accident prevention measures are primarily based on statistical data on the damage caused to substation lightning rods by Typhoon Mujigae. The data shows that lattice-type substation lightning rods suffered severe damage during Typhoon Mujigae, while single-column steel pipe lightning rods showed no damage. Analysis indicates that lattice-type lightning rods have numerous components, making construction quality difficult to guarantee and prone to creating structural weaknesses; therefore, single-column steel pipe lightning rods have a clear advantage.

[0007] Based on the stress characteristics of lightning rods, single-column steel pipe lightning rods in substations adopt a stepped variable cross-section design, meaning that different diameter single steel pipes are used in each section, with flanges connecting the upper and lower sections. For independent lightning rods, the rod base is rigidly connected to the foundation using anchor bolts. Summary of the Invention

[0008] The technical problem to be solved by this invention is to provide a method for calculating the performance of a single-column steel tube lightning rod, which comprehensively calculates and monitors the performance parameters of the single-column steel tube lightning rod to ensure the structural safety of the lightning rod.

[0009] To address the aforementioned technical problems, this invention provides a method for calculating the performance of a single-column steel tube lightning rod, comprising: acquiring load parameters and performing load combination calculations, gravity load calculations, wind load calculations, and internal force standard value calculations on the single-column steel tube lightning rod based on the load parameters; acquiring component parameters and performing component strength verification, component deformation verification, and component stability verification on the single-column steel tube lightning rod based on the component parameters; acquiring connection parameters and performing flange bolt strength verification, flange plate strength verification, stiffening plate strength verification, and stiffening plate weld verification on the single-column steel tube lightning rod based on the connection parameters; and performing real-time monitoring of the single-column steel tube lightning rod based on the calculation results and verification results.

[0010] As an improvement to the above scheme, the single-column steel pipe lightning rod type includes frame lightning rods and independent lightning rods; the frame lightning rod is divided into five sections, of which the first and second sections are combined to form the tip section, the third and fourth sections are combined to form the middle section, and the fifth section is the ground wire column section; the independent lightning rod is divided into five sections, of which the first and second sections are combined to form the tip section, and the third, fourth, and fifth sections are combined to form the non-tip section.

[0011] As an improvement to the above scheme, the steps for load combination calculation of a single-column steel tube lightning rod based on load parameters include: verifying the strength and stability of the rod tip segment, where, S d =1.0S Gk +1.0S Wk Strength and stability verification were performed on the middle section and non-needle tip section. Specifically, under unfavorable gravity load conditions, S... d =1.3S Gk +1.5S Wk When gravity load is favorable, S d =1.0S Gk +1.5S Wk Deformation calculations were performed on the middle section and non-needle tip section, where S d =S Gk +0.5S Wk The strength and stability of the grounding wire segment were verified, including under unfavorable gravity load conditions, S d =1.3S Gk +1.5S Wk +1.4S Dk When gravity load is favorable, S d =1.0S Gk +1.5S Wk +1.4S Dk Deformation calculations were performed on the ground wire column segment, where Sd =S Gk +0.5S Wk +S Dk S Gk S represents the standard value of the gravity load effect of each section of the steel pipe. Gk S represents the standard value of the wind load effect on each section of the steel pipe. Dk This is the standard value of the ground wire load effect.

[0012] As an improvement to the above scheme, the steps for calculating the gravity load, wind load, and standard internal force value of a single-column steel pipe lightning rod based on load parameters include: calculating the gravity load G of each section of the steel pipe. k0 Among them, G k0 =g k l,g k Let l represent the standard value of the gravity load per unit length of each steel pipe segment, and l represent the unit length of each steel pipe segment. Based on the gravity load of each steel pipe segment, calculate the correction value G for the gravity load of each segment. k Among them, G k =αG k0 G k0 Here are the standard values ​​of gravity load for each section of the steel pipe, and α is the correction factor for the gravity load of the lightning rod; calculate the standard value of wind load w for each section of the steel pipe. k and the standard value of wind load line load W for each section of steel pipe k , where w k =α h β z μ s μ z w0, W k =w k d, α h β is the basic wind pressure amplification factor for tall structures. z For the wind vibration coefficient at a specific altitude, μ s Let μ be the wind load shape coefficient for each section of the steel pipe. z Here, w0 is the wind pressure height variation coefficient for each section of the steel pipe at a specific height, d is the basic wind pressure, and d is the pipe diameter of each section; calculate the standard value N of the axial force at the calculated section of each section of the steel pipe. k ,in,

[0013]

[0014] Calculate the standard value of shear force V caused by wind load at the calculated cross section of each steel pipe segment. wk ,in,

[0015]

[0016] Calculate the standard value of shear force V of the calculated cross section of the ground wire column steel pipe caused by the ground wire load. Dk ,in,

[0017] V Dk =T Dk

[0018] Calculate the standard value M of the bending moment caused by wind load at the calculated cross section of each steel pipe segment. wk ,in,

[0019]

[0020] Calculate the standard value of the bending moment M caused by the ground wire load on the calculated cross section of the steel pipe section of the ground wire column. Dk ,in,

[0021] M Dk =T DK l5

[0022] T DK For ground wire load, l i Let W be the length of the i-th segment of the steel pipe. ki Let be the standard value of the wind load line load for the i-th segment of the steel pipe.

[0023] As an improvement to the above scheme, the steps for performing structural strength verification on a single-column steel tube lightning rod based on component parameters include: performing structural strength verification on the single-column steel tube lightning rod.

[0024]

[0025] N = γ G N k

[0026] For each section of the independent lightning rod and the first to fourth sections of the frame lightning rod, M x =γ w M wk For the fifth section of the lightning rod in the structure, M x =γ w M wk +γ D M Dk N represents the design value of the axial force for the calculated section strength and stability check of each steel pipe segment, and A represents... n Calculate the net cross-sectional area of ​​each section of the steel pipe, M. x For each section of the steel pipe, calculate the cross-sectional strength and verify the design bending moment value, γ. x W is the coefficient for plastic development of the cross section. nx Calculate the net section modulus of each steel pipe section, α1 is the strength reduction factor for each steel section, f is the design value of the tensile strength of each steel pipe section, and γ is the net section modulus of each steel pipe section. G γ is the partial factor for gravity load. W γ is the wind load partial factor. D This is the partial factor for ground wire load.

[0027] As an improvement to the above scheme, the steps for verifying the deformation of a single-column steel tube lightning rod based on component parameters include: dividing the load bending moment diagrams of the third to fifth steel tube segments into three types according to the number of steel tube segments: rectangular, triangular, and parabolic; calculating their areas and centroid positions respectively; and obtaining the unit bending moment diagram values ​​corresponding to each centroid position, as detailed below:

[0028] Regarding the third paragraph:

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036] Regarding the fourth paragraph:

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044] Regarding the fifth paragraph:

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053] W q =ψ qw W wk

[0054] M q =ψ qw M wk

[0055] For the third to fifth sections of independent lightning rods and the third to fourth sections of frame lightning rods:

[0056] V q =ψ qw V wk

[0057] The fifth section of the lightning rod structure:

[0058] V q =ψ qw V wk +ψ qD V Dk

[0059]

[0060] A 矩形 For each section of steel pipe, M P The total area of ​​the rectangular portion in the diagram, A 三角形 Let A be the total area of ​​the triangular portion in the bending moment diagram for each load on each section of the steel pipe. 抛物线 The total area of ​​the parabolic portion in the bending moment diagram of each section of the steel pipe under each load is y. 矩形 The unit bending moment diagram values ​​corresponding to the centroid coordinates of the rectangular areas in the bending moment diagrams for each section of the steel pipe under various loads are y. 三角形 The unit bending moment diagram values ​​corresponding to the centroid coordinates of the triangle area in the bending moment diagrams for each section of the steel pipe under each load are given by y. 抛物线 The values ​​for the unit bending moment diagrams are: l = length of each steel pipe segment, I = moment of inertia of the calculated section of each steel pipe segment, E = elastic modulus of the steel in each steel pipe segment, and V = length of each steel pipe segment. q ψ represents the shear force value calculated for the quasi-permanent combination at the apex section of each steel pipe segment. qw W is the quasi-permanent coefficient for wind load. q M represents the wind load line load value calculated for each section of steel pipe according to the quasi-permanent combination. q ψ represents the bending moment value calculated for the quasi-permanent combination at the vertex section of each steel pipe segment. qD H is the quasi-permanent value coefficient for ground wire load. u This refers to the total length of the third to fifth sections of the steel pipe.

[0061] As an improvement to the above scheme, the steps for performing stability verification on a single-column steel tube lightning rod based on component parameters include:

[0062] Perform diameter-to-thickness ratio verification:

[0063] d / t≤100(235 / fy)

[0064] t represents the wall thickness of each steel pipe section, and fy represents the yield strength of the steel in each steel pipe section; stability calculations are performed on the lowest section sections of the third to fifth sections of independent lightning rods subjected only to wind loads and the third and fourth sections of frame lightning rods:

[0065]

[0066]

[0067]

[0068] β N β is the correction factor for the axial force stress component. mx The equivalent bending moment coefficient is M, where M is the design value of the bending moment for stability verification of each section of the steel pipe, N is the design value of the axial force for stability verification of each section of the steel pipe, and W is the design value of the axial force for stability verification of each section of the steel pipe. x Calculate the gross section modulus N' for each section of the steel pipe. Ex Here are the stability calculation parameters for each section of the steel pipe, where A is the calculated cross-sectional area of ​​each section of the steel pipe, and λ is the value of λ. x Let L0 be the slenderness ratio of each steel pipe segment, L0 be the calculated length of each steel pipe segment for overall stability verification under wind load, and i be the slenderness ratio of each segment. x Calculate the radius of gyration for each section of the steel pipe; perform stability verification on the fifth section of the lightning rod in the structure:

[0069]

[0070] M D =γ D M Dk

[0071] L D =2l5

[0072] β N β is the correction factor for the axial force stress component. mx M is the equivalent bending moment coefficient. w M is the design value of the bending moment for stability verification of the calculated section caused by wind load. D N′ is the design value of the bending moment for stability verification of the calculated section caused by the ground wire load. Exw The stability calculation parameter N′ caused by wind load ExD L is the stability calculation parameter caused by the ground wire load.D This refers to the length used in the overall stability verification of the fifth section of the steel pipe under ground wire load.

[0073] As an improvement to the above scheme, the steps for verifying the strength of flange bolts of a single-column steel tube lightning rod based on connection parameters include: calculating the tensile force of the lightning rod flange bolts.

[0074]

[0075] Determine the tensile force of the lightning rod flange bolts Does it satisfy the following relationship:

[0076]

[0077]

[0078] If the determination is yes, then the strength of the flange bolts is checked; M is the design value of the bending moment at the flange of each section of the steel pipe, N is the design value of the axial force at the flange of each section of the steel pipe, and Y... i Y1 is the distance from the bolt center to the rotation axis, where Y1 is the distance from the bolt center under maximum force to the rotation axis, and n is the number of bolts on the flange. d is the design value of the tensile bearing capacity of a bolt. e This is the effective diameter of the bolt at the thread. The design value for the tensile strength of the bolts; the steps for verifying the flange strength based on the connection parameters include: calculating the uniformly distributed load q on the grid plates divided by the stiffening plate and the outer wall of the steel pipe. b :

[0079] l x l is the length of the free edge of the grid plate. y Given the side lengths of the adjacent sides of the grid plate and the free edge; calculate the bending moment M of the grid divided by the stiffening plate and the outer wall of the steel pipe. 0x :

[0080]

[0081] β b According to l y / l x The preset parameters are the ratio coefficients of the side lengths of the partition plates; calculate the bending moment t of the partitions divided by the stiffening plates and the outer wall of the steel pipes. b :

[0082]

[0083] f b The design value for the tensile strength of the flange plate; the steps for verifying the strength of the stiffening plate based on the connection parameters include: calculating the maximum shear stress τ of the stiffening plate.j and the maximum normal stress value σ of the stiffening plate j :

[0084]

[0085]

[0086] Determine the maximum shear stress τ of the stiffened plate j and the maximum normal stress value σ of the stiffening plate j Do they all satisfy the following relationship:

[0087] τ j ≤α1f νj

[0088] σ j ≤α1f j

[0089] If the determination is yes, then the strength is checked by the stiffening plate on the flange; h j For the height of the stiffening plate, t j For the stiffening plate thickness, f νj is the design value of the shear strength of the stiffening plate, b is the distance from the center line of the bolt hole to the outer wall of the steel pipe, and f is the design value of the shear strength of the stiffening plate. j The tensile strength design value for the stiffening plate; the steps for verifying the stiffening plate welds based on the connection parameters include: verifying the vertical fillet welds of the stiffening plates on the flange, specifically including: calculating the maximum shear stress τ generated by the vertical fillet welds. f and the maximum normal stress σ generated by the vertical fillet weld. f :

[0090]

[0091]

[0092] Determine the maximum shear stress τ generated by the vertical fillet weld. f and the maximum normal stress σ generated by the vertical fillet weld. f Does it meet the following relationship:

[0093]

[0094]

[0095]

[0096] If the determination is yes, then the calculation is performed using the vertical fillet weld of the stiffening plate on the flange; h e For the effective height of the vertical fillet weld, l w The effective length of the vertical fillet weld. β is the design value for the strength of the vertical fillet weld. fThe strength design value of the front fillet weld is increased by a factor; the horizontal fillet weld of the stiffening plate on the flange is checked, and the specific steps include: calculating the maximum shear stress τ generated by the horizontal fillet weld. fh :

[0097]

[0098] Determine the maximum shear stress τ generated by the horizontal fillet weld. fh Does it meet the following relationship:

[0099]

[0100] If the determination is yes, then the calculation is performed using the horizontal fillet weld of the stiffening plate on the flange; h eh The effective height of the horizontal fillet weld is equal to 0.7 times the horizontal weld height h. fh , l wh The effective length of the horizontal fillet weld is equal to the actual weld length l. fh Subtract 2 times the weld height h fh , This is the design strength value for horizontal fillet welds.

[0101] As an improvement to the above scheme, when the single-column steel tube lightning rod is an independent lightning rod, the performance calculation method for the single-column steel tube lightning rod also includes: obtaining the column base parameters, and performing strength verification of the column base plate and foundation concrete, shear key calculation, stiffening plate calculation, and anchor bolt design verification based on the column base parameters; the step of performing strength verification of the column base plate and foundation concrete based on the column base parameters includes: based on the fifth section pipe diameter d5 and the initially selected anchor bolt diameter d M Initial determination of the outer diameter d of the column base plate b Calculate the outer edge distance a of the anchor bolt hole M and inner margin b M :

[0102] a M =5*(INT(d M +2)*2 / 5)+1)

[0103] b M =5*(INT(d M +2)*2.5 / 5)+1)

[0104] According to the outer edge distance a of the anchor bolt hole M and inner margin b M Calculate the outer diameter d of the column base plate b :

[0105] d b =d5+2a M +2b M

[0106] Verify the maximum compressive stress σ in the column base concrete. 1 max The specific steps include: calculating the maximum compressive stress σ in the column base concrete. 1 max :

[0107]

[0108] Determine the maximum compressive stress σ in the column base concrete 1 max Does it meet the following relationship:

[0109] σ 1 max ≤f c

[0110] If the determination is yes, then the maximum compressive stress in the column base concrete is checked; N M The design value of the axial force at the column base is taken as the design value of the axial force at the calculated section of the lower end of the fifth steel pipe segment, A. M M is the cross-sectional area of ​​the column base plate. M The design value of the column base bending moment is taken as the design value of the bending moment at the lower end of the fifth steel pipe section, W. M f is the section modulus of the column base plate. c This is the design value for the axial compressive strength of concrete.

[0111] Calculate the minimum thickness t of the column base plate min :

[0112]

[0113] M 0 max To calculate the bending moment per unit length on the most unfavorable grid section under the action of foundation reaction force, where f is the design tensile strength of the steel in the column base plate and α1 is the steel strength reduction factor; calculate the maximum bending moment M per unit length in the grid section of the column base plate. 0 max :

[0114]

[0115] Where, σ c β2 represents the average stress of the concrete at the bottom of the grid plate in the most unfavorable zone, and β2 is a parameter preset according to b2 / a2, where a2 and b2 are the lengths of the free side and the adjacent side of the plate, respectively.

[0116] As an improvement to the above scheme, the steps for calculating the shear key based on the column base parameters include: calculating the embedment depth h of the shear key. j , where h j =1.45V j / f c b j +h j0 V j h is the design value of the column base shear force. j0 For ineffective embedment depth, the welds between the shear key and the column base plate should be welded with equal strength.j This represents the width of the shear key.

[0117] As an improvement to the above scheme, the steps for calculating the stiffening plate based on the column base parameters include: drawing the foundation reaction diagram of the base plate, obtaining the length x of the compressive stress distribution on one side of the base plate, and obtaining the compressive stress σ at the edge of the column outer diameter caused by the foundation reaction. 2 max ; Calculate the foundation reaction force within the base plate grid that the stiffening plate section can withstand:

[0118]

[0119]

[0120] The specific steps for performing strength verification of the stiffening plate at the column base include: calculating the maximum shear stress τ of the stiffening plate at the column base. s and the maximum normal stress value σ of the stiffening plate of the column base plate s :

[0121]

[0122]

[0123] Determine the maximum shear stress τ of the stiffening plate of the column base plate. s and the maximum normal stress value σ of the stiffening plate of the column base plate s Do they all meet the following relationship:

[0124] τ s ≤α1f ν

[0125] σ s ≤α1f

[0126] If the determination is yes, then the strength of the stiffening plate at the column base is checked; h j For the effective height of the stiffening plate of the column base plate, t j For the stiffening plate thickness of the column base plate, f ν The design value of the shear strength of the stiffening plate at the column base, σ s Let f be the maximum normal stress value of the stiffening plate of the column base plate, and f be the design value of the tensile strength of the stiffening plate of the column base plate. The weld calculation of the stiffening plate of the column base plate is performed. The steps for performing the weld calculation of the stiffening plate of the column base plate include: performing the calculation of the vertical fillet welds of the stiffening plate of the column base plate; performing the calculation of the horizontal fillet welds of the stiffening plate of the column base plate. The specific steps for performing the calculation of the vertical fillet welds of the stiffening plate of the column base plate include: calculating the maximum shear stress τ generated by the vertical fillet weld. f and the maximum normal stress σ generated by the vertical fillet weld. f :

[0127]

[0128]

[0129] Determine whether the maximum shear stress and the maximum normal stress generated by the vertical fillet weld both conform to the following relationship:

[0130]

[0131]

[0132]

[0133] If the determination is yes, then the calculation is performed using the vertical fillet weld of the stiffening plate at the column base; h e For the effective height of the vertical fillet weld, l w The effective length of the vertical fillet weld. β is the design value for the strength of the vertical fillet weld. f The strength design value of the front fillet weld is increased by a factor; the specific steps for verifying the horizontal fillet weld of the stiffening plate of the column base plate include: calculating the maximum shear stress τ generated by the horizontal fillet weld. fh :

[0134]

[0135] Determine the maximum shear stress τ generated by the horizontal fillet weld. fh Does it satisfy the following relationship:

[0136]

[0137] If the determination is yes, then the calculation is performed through the horizontal fillet weld of the stiffening plate at the column base; h eh For the effective height of the horizontal fillet weld, l wh The effective length of the horizontal fillet weld. This is the design strength value for horizontal fillet welds.

[0138] As an improvement to the above scheme, the steps for anchor bolt design verification based on column base parameters include: setting the bending moment M. M The design value of the bending moment at the bottom of the fifth steel pipe section, and the axial force in N. M This is the standard value of the axial force at the bottom of the fifth section of the steel pipe;

[0139] Calculate M M N M The maximum compressive stress σ under action max The hypothetical maximum tensile stress σ min The compressive stress distribution length x and eccentricity e on one side of the bottom of the plate = M M / N M :

[0140]

[0141]

[0142] B is the width of the column base plate, and L is the length of the column base plate;

[0143] Based on the maximum compressive stress σ on one side of the base plate max And the hypothetical maximum tensile stress σ on the other side min Determine the length x of the compressive stress distribution on one side of the base plate;

[0144] Calculate the effective cross-sectional area A of a single anchor bolt. c :

[0145]

[0146] e>(d b / 6+x / 3)

[0147] n i Here, represents the number of anchor bolts on one side of the column base, 'e' represents the eccentricity, and 'c' represents the distance from the outer edge of the anchor bolts at the column base. β is the design value of the tensile strength of the anchor bolt. x This is the tolerance factor for anchor bolt corrosion.

[0148] The beneficial effects of implementing this invention are as follows:

[0149] The performance calculation method for single-column steel tube lightning rods of this invention is implemented to comprehensively calculate and monitor the performance parameters of single-column steel tube lightning rods, ensuring the structural safety of the lightning rods.

[0150] Specifically, the performance of lightning rods can be mainly divided into three categories: internal force performance, component performance, and connection performance. By acquiring load parameters and performing load combination calculations, gravity load calculations, wind load calculations, and internal force standard value calculations on single-column steel tube lightning rods based on these parameters, a comprehensive parameter calculation and monitoring of the lightning rod's internal force performance can be achieved. By acquiring component parameters and performing component strength verification, deformation verification, and stability verification on single-column steel tube lightning rods based on these parameters, a comprehensive parameter calculation and monitoring of the lightning rod's structural performance can be achieved. By acquiring connection parameters and performing flange bolt strength verification, flange plate strength verification, stiffening plate strength verification, and stiffening plate weld verification on single-column steel tube lightning rods based on these parameters, a comprehensive parameter calculation of the connection performance can be achieved. Finally, the single-column steel tube lightning rod is monitored in real time based on the calculation and verification results, thereby ensuring the structural safety of the lightning rod. Attached Figure Description

[0151] Figure 1 This is the overall flowchart of the performance calculation method for a single-column steel tube lightning rod of the present invention;

[0152] Figure 2This is a flowchart of the method for calculating the performance of a single-column steel tube lightning rod according to the load parameters.

[0153] Figure 3 This is a flowchart of the single-column steel tube lightning rod performance calculation method of the present invention, which calculates gravity load, wind load and internal force standard value of single-column steel tube lightning rod according to load parameters;

[0154] Figure 4 This is the actual wind load line load distribution diagram of the single-column steel tube lightning rod performance calculation method of the present invention;

[0155] Figure 5 This is a simplified wind load line load distribution diagram of the single-column steel tube lightning rod performance calculation method of the present invention;

[0156] Figure 6 This invention provides a simplified diagram of the stress distribution for calculating the deformation of a single-column steel tube lightning rod, based on the performance calculation method of the invention.

[0157] Figure 7 This is a unit bending moment diagram of the performance calculation method for a single-column steel tube lightning rod according to the present invention. picture);

[0158] Figure 8 The third section of the single-column steel pipe lightning rod performance calculation method of this invention relates to the shear force M at the top of the steel pipe. P picture;

[0159] Figure 9 The third section of the steel pipe apex bending moment M is the calculation method for the performance of a single-column steel pipe lightning rod of this invention. P picture;

[0160] Figure 10 This is the fourth section of the performance calculation method for a single-column steel tube lightning rod of the present invention, which calculates the wind load M on the steel tube. P picture;

[0161] Figure 11 This is the third section of the performance calculation method for a single-column steel tube lightning rod of the present invention, which calculates the wind load M on the steel tube. P picture;

[0162] Figure 12 This is the fifth section of the performance calculation method for a single-column steel tube lightning rod of the present invention, concerning the wind load M on the steel tube. P picture;

[0163] Figure 13 This invention relates to a method for calculating the performance of a single-column steel tube lightning rod, specifically the method for calculating the horizontal tension M of the ground wire. P picture;

[0164] Figure 14is a flow chart of the performance calculation method for the single-column steel tube lightning rod of the present invention, which performs component deformation check on the single-column steel tube lightning rod according to component parameters;

[0165] Figure 15 is a flow chart of the performance calculation method for the single-column steel tube lightning rod of the present invention, which performs component stability check on the single-column steel tube lightning rod according to component parameters;

[0166] Figure 16 is a calculation schematic diagram of the modified length coefficient μ1 in the performance calculation method for the single-column steel tube lightning rod of the present invention;

[0167] Figure 17 is a flow chart of the performance calculation method for the single-column steel tube lightning rod of the present invention, which performs flange bolt strength check on the single-column steel tube lightning rod according to connection parameters;

[0168] Figure 18 is a schematic diagram of taking the tangent of the outer wall of the steel tube as the rotation axis when M / |N|≥d / 2 in the performance calculation method for the single-column steel tube lightning rod of the present invention;

[0169] Figure 19 is a schematic diagram of taking the center line of the steel tube as the rotation axis when M / |N|<d / 2 in the performance calculation method for the single-column steel tube lightning rod of the present invention;

[0170] Figure 20 is a stress diagram of the stiffened flange plate in the performance calculation method for the single-column steel tube lightning rod of the present invention Figure 1 ;

[0171] Figure 21 is a stress diagram of the stiffened flange plate in the performance calculation method for the single-column steel tube lightning rod of the present invention Figure 2 ;

[0172] Figure 22 is a stress diagram of the stiffened flange plate in the performance calculation method for the single-column steel tube lightning rod of the present invention Figure 3 ;

[0173] Figure 23 is a flow chart of performing flange plate strength check according to connection parameters in the performance calculation method for the single-column steel tube lightning rod of the present invention;

[0174] Figure 24 is a flow chart of performing stiffened plate strength check according to connection parameters in the performance calculation method for the single-column steel tube lightning rod of the present invention;

[0175] Figure 25 is a flow chart of performing vertical fillet weld check for the stiffened plate on the flange in the performance calculation method for the single-column steel tube lightning rod of the present invention;

[0176] Figure 26This is a flowchart of the calculation method for the horizontal fillet weld of the stiffening plate on the flange in the single-column steel tube lightning rod performance calculation method of the present invention.

[0177] Figure 27 This is a flowchart of the single-column steel tube lightning rod performance calculation method of the present invention, which verifies the strength of the column base plate and foundation concrete based on the column base parameters.

[0178] Figure 28 This is a flowchart of the method for calculating the performance of a single-column steel tube lightning rod according to the column base parameters.

[0179] Figure 29 This is a flowchart of the calculation method for the vertical fillet weld of the stiffening plate of the column base plate in the single-column steel tube lightning rod of the present invention.

[0180] Figure 30 This is a flowchart of the calculation method for the horizontal fillet weld of the stiffening plate of the column base plate in the single-column steel tube lightning rod of the present invention.

[0181] Figure 31 This is a flowchart of the single-column steel tube lightning rod performance calculation method of the present invention, which performs anchor bolt design verification based on column base parameters;

[0182] Figure 32 This is a simplified diagram of the anchor bolt calculation method for the single-column steel pipe lightning rod performance calculation method of the present invention. Detailed Implementation

[0183] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It is hereby declared that the directional terms such as up, down, left, right, front, back, inside, and outside used in this text are based solely on the accompanying drawings and are not intended to specifically limit the invention.

[0184] Figure 1 This is a flowchart illustrating the overall process for calculating the performance of a single-column steel tube lightning rod according to the present invention, which includes:

[0185] S101 obtains load parameters and performs load combination calculations, gravity load calculations, wind load calculations, and internal force standard value calculations for single-column steel tube lightning rods based on the load parameters.

[0186] S102. Obtain component parameters, and perform component strength verification, component deformation verification, and component stability verification on single-column steel pipe lightning rods based on the component parameters.

[0187] S103. Obtain the connection parameters, and perform flange bolt strength verification, flange plate strength verification, stiffening plate strength verification, and stiffening plate weld verification on the single-column steel pipe lightning rod according to the connection parameters.

[0188] S104. Real-time monitoring of single-column steel tube lightning rods based on calculation and verification results.

[0189] The beneficial effects of implementing this invention are as follows:

[0190] The performance calculation method for single-column steel tube lightning rods of this invention is implemented to comprehensively calculate and monitor the performance parameters of single-column steel tube lightning rods, ensuring the structural safety of the lightning rods.

[0191] Specifically, the performance of lightning rods can be mainly divided into three categories: internal force performance, component performance, and connection performance. By acquiring load parameters and performing load combination calculations, gravity load calculations, wind load calculations, and internal force standard value calculations on single-column steel tube lightning rods based on these parameters, a comprehensive parameter calculation and monitoring of the lightning rod's internal force performance can be achieved. By acquiring component parameters and performing component strength verification, deformation verification, and stability verification on single-column steel tube lightning rods based on these parameters, a comprehensive parameter calculation and monitoring of the lightning rod's structural performance can be achieved. By acquiring connection parameters and performing flange bolt strength verification, flange plate strength verification, stiffening plate strength verification, and stiffening plate weld verification on single-column steel tube lightning rods based on these parameters, a comprehensive parameter calculation of the connection performance can be achieved. Finally, the single-column steel tube lightning rod is monitored in real time based on the calculation and verification results, thereby ensuring the structural safety of the lightning rod.

[0192] Furthermore, single-column steel pipe lightning rods include frame lightning rods and independent lightning rods;

[0193] The lightning rod structure is divided into five sections: the first and second sections are combined to form the tip section, the third and fourth sections are combined to form the middle section, and the fifth section is the grounding pole section.

[0194] According to Table 6.5.3 of the "Technical Specification for Design of Substation Building Structures" (hereinafter referred to as the "Substation Specification"), the tip of a lightning rod should not exceed 5m (for sections with a pipe diameter less than 150mm). Since the pipe diameter of the first and second sections is generally less than 150mm, both can be considered as the tip. Therefore, the total length of the first and second sections should not exceed 5m. Based on engineering experience, the length of the first section of a lightning rod is generally 1.0m. Therefore, the length of the second section is taken as 3.0m or 4.0m depending on the total length of the lightning rod.

[0195] Considering that the lightning rod is located on the outgoing side, the fifth section is actually a ground wire post, so the length of the fifth section of the lightning rod is taken according to the length of the ground wire post.

[0196] After determining the needle tip and ground wire column segments, the middle segment is then determined. To ensure structural stability, the fourth segment is slightly longer than the third segment.

[0197] The segmentation of each type of lightning rod is shown in Table 1:

[0198]

[0199] Table 1

[0200] Before performing lightning rod design calculations, the required lightning rod model must first be determined. Table 1-1 summarizes six lightning rod models based on common substation structure lightning rods. Among them, 500-A to 500-D are 500kV site-connected structure lightning rods, corresponding to low-rise and high-rise lightning rods in HGIS layouts and low-rise and high-rise lightning rods in conventional outdoor layouts, respectively; the 220 model is a 220kV structure lightning rod; and the 110 model is a 110kV structure lightning rod. The bottom and top elevations, total lengths, and segmentation of each lightning rod model are different.

[0201] The initial cross-section and steel grade of each section of the lightning rod steel pipe are selected, and the material parameters of each section are determined based on the initial selection results. Generally, the diameter of the first section is no greater than 60mm, the diameter of the second section is no greater than 100mm, and the diameters of the third and fifth sections are taken as 150-200mm and 350-500mm respectively, based on the wind pressure and the total length of the lightning rod. The diameter of the fourth section is determined by interpolation between the diameters of the fifth and third sections. The steel type for the lightning rod is generally Q235. For the fifth section, when the wind pressure is relatively high and the total length of the lightning rod is relatively long, Q345 can be selected. Taking model 500-A, basic wind pressure 0.85kN / m2, and Class B site as an example, the preliminary values ​​of each material parameter are shown in Table 2:

[0202]

[0203] Table 2

[0204] An independent lightning rod consists of five sections, with the first and second sections forming the tip section and the third, fourth, and fifth sections forming the non-tip section.

[0205] Independent lightning rods are divided into five categories based on their total height: 15m, 20m, 25m, 30m, and 35m. All lightning rods are divided into five sections of equal diameter, which are numbered sequentially from top to bottom.

[0206] According to Table 6.5.3 of the "Substation Regulations," the tip of a lightning rod should not exceed 5m (for sections with a pipe diameter less than 150mm). Since the diameter of the first and second sections is generally less than 150mm, both can be considered as the tip. Therefore, the total length of the first and second sections should not exceed 5m. Based on engineering experience, the length of the first section of a lightning rod is generally 1.0m. Therefore, the length of the second section is taken as 3.0m or 4.0m depending on the total length of the lightning rod.

[0207] After determining the needle tip segment, the non-needle tip segment is then determined. To ensure structural stability, the fifth segment is longer than or equal to the fourth segment, and the fourth segment is longer than or equal to the third segment.

[0208] The segmentation of each type of independent lightning rod is shown in Table 3:

[0209]

[0210]

[0211] Table 3

[0212] The initial cross-section and steel grade of each independent lightning rod steel pipe are selected, and the material parameters of each section are determined based on the initial selection results. Generally, the diameter of the first section is no greater than 60mm, the diameter of the second section is no greater than 100mm, and the diameters of the third and fifth sections are taken as 150-200mm and 350-550mm respectively, based on the wind pressure and the total length of the lightning rod. The diameter of the fourth section is determined by interpolation between the diameters of the fifth and third sections. The steel grade for the lightning rod is generally Q235. For the fifth section, when the wind pressure is relatively high and the total length of the lightning rod is relatively long, Q345 can be selected. Taking a 30m model, a basic wind pressure of 0.85kN / m2, and a Class B site as an example, the preliminary values ​​of each material parameter are shown in Table 4:

[0213]

[0214] Table 4

[0215] The specific calculation steps of the single-column steel tube lightning rod performance calculation method of the present invention are explained below.

[0216] According to Article 7.6.11 of the "Code for Seismic Design of Power Facilities", lightning rods in stations with a seismic fortification intensity of less than 9 degrees do not need to undergo cross-sectional seismic verification. Therefore, the seismic action is not considered in the cross-sectional verification of lightning rods.

[0217] Figure 2 This is a flowchart of load combination calculations for a single-column steel tube lightning rod based on load parameters. The steps include:

[0218] S201. The strength and stability of the needle tip segment are verified, wherein S d =1.0S Gk +1.0S Wk ;

[0219] It should be noted that deformation calculations are not required for the tip section. Step S201 applies to both frame lightning rods and independent lightning rods.

[0220] Where S d The value reflects the effect of the load on the component, such as internal force, displacement, deformation, etc.

[0221] S202. Strength and stability verification of the intermediate section is conducted, including verification under unfavorable gravity load conditions. d =1.3S Gk +1.5S Wk When gravity load is favorable, Sd =1.0S Gk +1.5S Wk ;

[0222] S203. Perform deformation verification on the middle section, where S d =S Gk +0.5S Wk ;

[0223] S204. Strength and stability verification of the grounding wire segment is conducted, including verification under unfavorable gravity load conditions. d =1.3S Gk +1.5S Wk +1.4S Dk When gravity load is favorable, S d =1.0S Gk +1.5S Wk +1.4S Dk ;

[0224] S205. Deformation verification of the grounding wire column segment, where S d =S Gk +0.5S Wk +S Dk ;

[0225] Because the ground wire column segment has a ground wire load, the load effect combination should take into account the ground wire load effect. In particular, the ground wire load only considers the superposition of the horizontal tension of the ground wire and the wind load of the lightning rod structure, that is, the wind direction is along the direction of the conductor. The lateral wind pressure of the ground wire is not considered. The vertical load value of the ground wire is small and has little impact on the internal forces of the structure, so it is also not included.

[0226] According to Table 4.2.5 of the "Substation Code" and the latest "Unified Standard for Reliability Design of Building Structures" regarding load partial factors, the partial factor for ground wire load (horizontal tension) is taken as 1.4, which is 0.1 higher than that in Table 4.2.5 of the "Substation Code". For deformation verification, considering that most of the horizontal tension of the ground wire is the tension force generated by the weight of the ground wire, i.e., a dead load, its combination factor is taken as 1.0.

[0227] Steps S202-S205 apply to lightning rods in structural structures.

[0228] S206. Strength and stability verification of the non-needle tip section, including verification under unfavorable gravity load conditions. d =1.3S Gk +1.5S Wk When gravity load is favorable, S d =1.0S Gk +1.5S Wk ;

[0229] S207. Deformation verification is performed on the non-needle tip segment, where S d =S Gk +0.5S Wk ;

[0230] S Gk S represents the standard value of the gravity load effect of each section of the steel pipe. Gk S represents the standard value of the wind load effect on each section of the steel pipe. Dk This is the standard value of the ground wire load effect.

[0231] Steps S206-S207 apply to independent lightning rods.

[0232] Figure 3 This is a flowchart illustrating the calculation of gravity load, wind load, and standard internal force values ​​for a single-column steel tube lightning rod based on load parameters. The steps include:

[0233] S301. Calculate the gravity load G of each section of the steel pipe. k0 Among them, G k0 =g k l,g k Let l be the standard value of gravity load per unit length of each steel pipe segment, and l be the unit length of each steel pipe segment.

[0234] S302. Calculate the correction value G of the gravity load of each section of the steel pipe based on the gravity load of each section. k Among them, G k =αG k0 G k0 Here, α represents the standard value of the gravity load for each section of the steel pipe, and α is the correction factor for the gravity load of the lightning rod. When the gravity load is unfavorable to the structure, α can be taken as 1.35. When the gravity load is favorable to the structure, α can be taken as 1.0.

[0235] When calculating the weight of frame lightning rods and independent lightning rods, the gravity load consists of the gravity load of the lightning rod steel pipe and the connecting parts. The gravity load of each steel pipe section is calculated in step S301. The calculation of the gravity load of the connecting parts is cumbersome; therefore, the total gravity load of all lightning rod sections can be obtained by introducing a correction factor into the gravity load of the steel pipe, i.e., in step S302.

[0236] S303. Calculate the standard value of wind load w for each section of the steel pipe. k (kN / m 2 The standard value of wind load line load W for each section of steel pipe. k (kN / m), where w k =α h β z μ s μ z w0, W k =w k d, αh α is the basic wind pressure amplification factor for tall structures. h Take 1.1, β z β is the wind vibration coefficient at a specific height. z 2.0 μ can be selected. s For each section of the steel pipe, μ is the wind load shape coefficient. For a circular steel pipe, μ is... z w0d 2 ≤0.002, take 1.2, μ z w0d 2 For values ​​≥0.015, take 0.6; intermediate values ​​are calculated using interpolation, μ. z The wind pressure height variation coefficient for each section of the steel pipe at a specific height is taken from Table 5, where w0 is the basic wind pressure (kN / m). 2 ), where d is the diameter of each section of the steel pipe;

[0237]

[0238] Table 5

[0239] The wind load line load of each steel pipe segment changes linearly with height, but the variation is small, and the variation decreases further towards the tip of the pipe. To simplify the calculation, the wind load line load of each steel pipe segment can be approximated as a uniformly distributed load, with the value taken as the line load value corresponding to 2 / 3 of the height from the bottom of each segment, i.e., zi is taken as the elevation value at 2 / 3 of the height of the i-th segment. The actual wind load line load distribution diagram and the simplified wind load line load distribution diagram are shown below. Figure 4 and Figure 5 As shown.

[0240] Steps S301-S303 apply to frame lightning rods and independent lightning rods.

[0241] For lightning rods on the frame structure, the fifth section, for lightning rods on the outgoing side, should be considered as a grounding post and the grounding load must be taken into account. As before, this manual only considers the horizontal tension of the grounding wire. According to relevant specifications and engineering experience, the standard value T of the horizontal tension of the grounding wire for each voltage level is... Dk Reference values ​​are shown in Table 6.

[0242]

[0243]

[0244] Table 6

[0245] Based on the stress characteristics of lightning rods, the most unfavorable section of each steel pipe member is the bottommost section. Therefore, the standard values ​​of each internal force at the calculated section of each steel pipe member are calculated as follows:

[0246] S304. Calculate the standard value of axial force N at the calculated section of each steel pipe segment. k ,in,

[0247]

[0248] S305. Calculate the standard value of shear force V caused by wind load at the calculated cross section of each steel pipe segment. wk ,in,

[0249]

[0250] S306. Calculate the standard value of shear force V of the steel pipe section of the grounding wire column caused by the grounding wire load. Dk ,in,

[0251] V Dk =T Dk

[0252] S307. Calculate the standard value of the bending moment M caused by wind load at the calculated section of each steel pipe segment. wk ,in,

[0253]

[0254] S308. Calculate the standard value of the bending moment M caused by the ground wire load on the calculated cross section of the ground wire column steel pipe. Dk ,in,

[0255] M Dk =T DK l5

[0256] T DK For ground wire load, l i Let W be the length of the i-th segment of the steel pipe. ki Let be the standard value of the wind load line load for the i-th segment of the steel pipe.

[0257] It should be noted that steps S304, S305, and S307 apply to both frame lightning rods and independent lightning rods. Steps S306 and S308 apply only to frame lightning rods.

[0258] When performing component and connection calculations for lightning rods in structural frameworks, the maximum design stress value should not exceed 70% of the steel strength design value specified in current national standards; for the lightning rod tip, the design stress under standard load should not exceed 80 N / mm². 2 .

[0259] The lightning rod structure bears horizontal wind loads, ground wire loads, and vertical gravity loads. Specifically: for sections one through four, only wind loads induce bending moments on the calculated cross-section. For section five, both wind loads and ground wire loads induce bending moments on the calculated cross-section. For wind loads, only the maximum unidirectional wind load is considered for the most unfavorable combination; for ground wire loads, only the superposition of horizontal tension and wind load in the same direction is considered for the most unfavorable combination.

[0260] Independent lightning rods withstand horizontal wind loads and vertical gravity loads. For wind loads, only the maximum wind load in one direction is considered for the most unfavorable combination.

[0261] The steps for performing strength verification on a single-column steel tube lightning rod based on component parameters include:

[0262] Structural strength verification of single-column steel tube lightning rod:

[0263]

[0264] N = γ G N k

[0265] For each section of the independent lightning rod and the first to fourth sections of the frame lightning rod, M x =γ w M wk (1) For the fifth section of the lightning rod in the structure, M x =γ w M wk +γ D M Dk ;

[0266] N represents the design value of the axial force for the calculated section strength and stability check of each steel pipe segment, and A... n Calculate the net cross-sectional area of ​​each section of the steel pipe, M. x For each section of the steel pipe, calculate the cross-sectional strength and verify the design bending moment value, γ. x W is the cross-sectional plastic development coefficient, taken as 1.0. nx Let α1 be the net section modulus of the calculated cross-section of each steel pipe segment, α1 be the strength reduction factor of each steel segment (taken as 0.7), f be the design value of the tensile strength of each steel pipe segment, and γ be the net section modulus. G For gravity load partial factors, take 1.0 for the first and second segments, and 1.3 for the third to fifth segments. γ W For wind load partial factors, take 1.0 for the first and second sections, and 1.5 for the third to fifth sections. γ D The partial factor for ground wire load is 1.4.

[0267] The lightning rod is a multi-step variable cross-section cantilever structure. The bending stiffness (EI) and external load of each segment of the steel pipe are different, making it impossible to directly use existing calculation formulas for deformation (displacement). According to structural mechanics, although the lightning rod is a stepped steel pipe, the EI of each segment is constant, and under a unit force at the apex... Since the graph is a straight line, the vertex displacement of the lightning rod can be calculated segment by segment using the graphical multiplication method.

[0268] According to Article 6.5.3 of the Substation Regulations, displacement calculation is not required for the tip of the lightning rod; that is, only the deformation of the third to fifth apex segments needs to be calculated, and the deformation limit is H. u / 70. H u This represents the total length of the third to fifth steel pipe sections. Based on the structural stress characteristics, the most unfavorable point for deformation verification is point A at the apex of the third section. A simplified diagram of the stress distribution for lightning rod deformation verification is shown below. Figure 6 As shown. Figure M shows the bending moment under various loads. P See image Figures 7 to 13 As shown. Among them, Figure 7 for picture, Figure 8 The shear force M at the apex of the third steel pipe segment P picture, Figure 9 The bending moment M at the top of the third steel pipe segment P picture, Figure 10 The wind load M of the fourth steel pipe section P picture, Figure 11 The wind load M of the third steel pipe section P picture, Figure 12 The fifth section of the steel pipe is subjected to wind load M. P picture, Figure 13 The horizontal tension M of the ground wire P picture.

[0269] Figure 14 This is a flowchart of the component deformation verification calculation for a single-column steel tube lightning rod based on component parameters. The steps include:

[0270] S401, Load bending moment diagrams (M) of the third to fifth steel pipe sections. P (Figure) According to the number of steel pipe sections, they are divided into three types: rectangular, triangular, and parabolic;

[0271] S402. Calculate the area and centroid location of each centroid location, and obtain the unit bending moment diagram corresponding to each centroid location. The values ​​shown in the figure are as follows:

[0272] Regarding the third paragraph:

[0273]

[0274]

[0275]

[0276]

[0277]

[0278]

[0279]

[0280] Regarding the fourth paragraph:

[0281]

[0282]

[0283]

[0284]

[0285]

[0286]

[0287]

[0288] Regarding the fifth paragraph:

[0289]

[0290]

[0291]

[0292]

[0293]

[0294]

[0295]

[0296]

[0297] W q =ψ qw W wk

[0298] M q =ψ qw M wk

[0299] For the third to fifth sections of independent lightning rods and the third to fourth sections of frame lightning rods:

[0300] V q =ψ qw V wk

[0301] The fifth section of the lightning rod structure:

[0302] V q =ψ qw V wk +ψ qD V Dk

[0303]

[0304] A 矩形 For each section of steel pipe, M P The total area of ​​the rectangular portion in the diagram, A 三角形 Let A be the total area of ​​the triangular portion in the bending moment diagram for each load on each section of the steel pipe. 抛物线 The total area of ​​the parabolic portion in the bending moment diagram of each section of the steel pipe under each load is y. 矩形 The unit bending moment diagram values ​​corresponding to the centroid coordinates of the rectangular areas in the bending moment diagrams for each section of the steel pipe under various loads are y. 三角形 The unit bending moment diagram values ​​corresponding to the centroid coordinates of the triangle area in the bending moment diagrams for each section of the steel pipe under each load are given by y. 抛物线 The values ​​for the unit bending moment diagrams are the centroid coordinates of the parabolic area in each load bending moment diagram of each steel pipe segment, where l is the length of each steel pipe segment, I is the calculated moment of inertia of each steel pipe segment, and E is the elastic modulus of the steel in each steel pipe segment, taken as 206000 N / mm². 2 V q ψ represents the shear force value calculated for the quasi-permanent combination at the apex section of each steel pipe segment. qw Let W be the quasi-permanent coefficient for wind load, taken as 0.5. q M represents the wind load line load value calculated for each section of steel pipe according to the quasi-permanent combination. q ψ represents the bending moment value calculated for the quasi-permanent combination at the vertex section of each steel pipe segment. qD H is the quasi-permanent value coefficient for ground wire load, taken as 1.0. u This refers to the total length of the third to fifth sections of the steel pipe.

[0305] It should be noted that steps S401 to S402 apply to both frame lightning rods and individual lightning rods.

[0306] Figure 15 This is a flowchart of the component stability verification calculation for a single-column steel tube lightning rod based on component parameters. The steps include:

[0307] S501. Perform diameter-to-thickness ratio verification:

[0308] d / t≤100(235 / f y )

[0309] t represents the wall thickness of each section of the steel pipe, f y The yield strength of the steel in each section of the steel pipe;

[0310] S502. Stability calculations are performed on the lowest section of the steel pipe of the third to fifth sections of independent lightning rods subjected only to wind loads, and on the third and fourth sections of frame lightning rods:

[0311]

[0312]

[0313]

[0314] β N β is the correction factor for the axial force stress component, taken as 1.05. mx The equivalent bending moment coefficient is taken as 1.0. M is the design value of the bending moment for stability verification of each section of the steel pipe, calculated with the same strength verification. N is the design value of the axial force for stability verification of each section of the steel pipe, calculated with the same strength verification. W x Calculate the gross section modulus N' for each section of the steel pipe. Ex Here are the stability calculation parameters for each section of the steel pipe, where A is the calculated cross-sectional area of ​​each section of the steel pipe, and λ is the value of λ. x Let L0 be the slenderness ratio of each steel pipe segment, and L0 be the calculated length for overall stability verification of each steel pipe segment under wind load. The calculation method is described below. x Calculate the radius of gyration of the cross section for each section of the steel pipe.

[0315] Steps S501 and S502 apply to both frame lightning rods and individual lightning rods. It should be noted that step S502, which performs stability checks based on the characteristics of frame lightning rods and individual lightning rods, does not mean performing stability checks on both types of lightning rods simultaneously. Instead, it provides two optional schemes: when the object of the check is an individual lightning rod, the stability check is performed on the third to fifth sections of the individual lightning rod subjected only to wind loads; when the object of the check is a frame lightning rod, the stability check is performed on the lowest section of the third and fourth steel pipe sections of the frame lightning rod. S503: Perform stability checks on the fifth section of the frame lightning rod:

[0316]

[0317] M D =γ D M Dk

[0318] L D =2l5 (3)

[0319] β N β is the correction factor for the axial force stress component, taken as 1.05. mx M is the equivalent bending moment coefficient, taken as 1.0. w The design value of the bending moment for stability verification of the calculated section caused by wind load is calculated according to formula (1), M D N′ is the design value of the bending moment for stability verification of the calculated section caused by the ground wire load. Exw The stability calculation parameters caused by wind load are calculated according to equation (2), and the corresponding calculation length is calculated according to equation (4), N′ ExD The stability calculation parameters caused by the ground wire load are calculated according to equation (2), and the corresponding calculation length is calculated according to equation (3), LD This refers to the length used in the overall stability verification of the fifth section of the steel pipe under ground wire load.

[0320] As a multi-stage variable cross-section cantilever structure, the moment of inertia (I) of each steel pipe segment in a lightning rod is different, making it impossible to directly use existing calculation formulas to determine the total calculated length of the multi-segment steel pipes for overall stability verification. The total calculated length of the multi-stage variable cross-section cantilever member can be derived using the energy method, with the specific calculation formula as follows:

[0321] L0=μ0μ1L (4)

[0322]

[0323] η i =(θ i +sinθ i ) / π

[0324] θ i =πχ i / L

[0325] μ0 is the initial length coefficient of the steel pipe used for overall stability verification, μ1 is the corrected length coefficient of the steel pipe used for overall stability verification, L is the total length from the calculation section of the overall stability verification to the vertex of the third steel pipe segment, and η i Calculate correction parameters for μ1 of each steel pipe segment, θ i The correction angle calculated for each section of steel pipe μ1, χ i This refers to the distance from the top of each steel pipe section to the overall stable calculation section.

[0326] Taking the lowest section of segment 5 as an example, the simplified calculation diagram for the corrected length factor μ1 is detailed below. Figure 16 .

[0327] This invention simplifies the overall stability calculation method while ensuring engineering safety as follows:

[0328] (1) Similar to deformation verification, the overall stability of the lightning rod tip does not need to be verified. Only the overall stability of the steel pipe sections 3 to 5 needs to be verified. The overall stability of the most unfavorable sections (lowest end sections) of sections 3, 4 and 5 should be verified separately (assuming that the section below the calculated section is the fixed end).

[0329] (2) Ignore the stability verification stress component directly caused by the axial force. This part of the stress component will be considered in the stress component caused by the bending moment in the form of a correction factor.

[0330] The above step S503 applies only to lightning rods in structural structures.

[0331] All sections of the lightning rod are connected by flanges, and each flange is equipped with a stiffening plate.

[0332] Figure 17 It is a flow chart of flange bolt strength checking for single-column steel tube lightning rod based on connection parameters, and its steps include:

[0333] S601, Calculate the tensile force of the flange bolts of the lightning rod

[0334]

[0335] S602, Determine whether the tensile force of the flange bolts of the lightning rod satisfies the following relationship:

[0336]

[0337]

[0338] S603, If the judgment result is yes, the flange bolt strength check is passed;

[0339] M is the designed bending moment value at each section of the steel tube flange, N is the designed axial force value at each section of the steel tube flange, Y i is the distance from the bolt center to the rotation axis. When M / |N|≥d / 2, the tangent of the outer wall of the steel tube is taken as the rotation axis, see Figure 18 rotation axis 1 in. When M / |N|<d / 2, the center line of the steel tube is taken as the rotation axis, see Figure 19 rotation axis 2 in. Y1 is the distance from the center of the bolt with the maximum force to the rotation axis, n is the number of bolts on the flange plate, is the designed tensile bearing capacity of a single bolt, d e is the effective diameter of the bolt at the thread, is the designed tensile strength of the bolt.

[0340] Figures 20 to 22 is the stress diagram of the stiffened flange plate.

[0341] Figure 23 It is a flow chart of flange plate strength checking based on connection parameters, and its steps include:

[0342] S701, Calculate the uniform load q on the panel divided by the stiffener and the outer wall of the steel tube b :

[0343]

[0344] l x is the length of the free edge of the panel, l y is the side length of the panel adjacent to the free edge;

[0345] S702, Calculate the bending moment M of the panel divided by the stiffener and the outer wall of the steel tube 0x :

[0346]

[0347] β b According to l y / l x The preset parameter is the ratio coefficient of the grid plate side length. For details of the setting, please refer to Table 7:

[0348] <![CDATA[β b ]]> 0.0273 0.0355 0.0439 0.0522 0.0602 0.0677 0.0747 ly / lx 0.65 0.7 0.75 0.8 0.85 0.9 1 <![CDATA[β b ]]> 0.0812 0.0871 0.0924 0.0972 0.1015 0.1053 0.1117 ly / lx 1.1 1.2 1.3 1.4 1.5 1.75 2 <![CDATA[β b ]]> 0.1167 0.1205 0.1235 0.1258 0.1275 0.1302 0.1316

[0349] Table 7S703, Calculation of the minimum thickness t of the flange plate b :

[0350]

[0351] f b This is the design value for the tensile strength of the flange plate;

[0352] Figure 24 This is a flowchart for calculating the strength of stiffening plates based on connection parameters. The steps include:

[0353] S801. Calculate the maximum shear stress τ of the stiffened plate. j and the maximum normal stress value σ of the stiffening plate j :

[0354]

[0355]

[0356] S802. Determine the maximum shear stress value τ of the stiffening plate. j and the maximum normal stress value σ of the stiffening plate j Do they all satisfy the following relationship:

[0357] τ j ≤α1f νj

[0358] σ j ≤α1f j

[0359] S803. If the judgment is yes, then the strength of the stiffening plate on the flange is checked.

[0360] h j For the height of the stiffening plate, t j For the stiffening plate thickness, f νj is the design value of the shear strength of the stiffening plate, b is the distance from the center line of the bolt hole to the outer wall of the steel pipe, and f is the design value of the shear strength of the stiffening plate. j This is the design value for the tensile strength of the stiffening plate;

[0361] The steps for verifying the stiffening plate weld based on the connection parameters include:

[0362] Perform verification calculations on the vertical fillet welds of the stiffening plates on the flanges;

[0363] Perform a calculation on the horizontal fillet weld of the stiffening plate on the flange.

[0364] The two steps described above will be explained in detail below.

[0365] Figure 25 This is a flowchart for verifying the vertical fillet weld of the stiffening plate on the flange. The specific steps include:

[0366] S901. Calculate the maximum shear stress τ generated by the vertical fillet weld. f and the maximum normal stress σ generated by the vertical fillet weld. f :

[0367]

[0368]

[0369] S902. Determine the maximum shear stress τ generated by a vertical fillet weld. f and the maximum normal stress σ generated by the vertical fillet weld. f Does it meet the following relationship:

[0370]

[0371]

[0372]

[0373] S903. If the judgment is yes, then the calculation is performed by checking the vertical fillet weld of the stiffening plate on the flange.

[0374] h e The effective height of the vertical fillet weld is equal to 0.7 times the weld height h. f , l w The effective length of the vertical fillet weld is equal to the actual weld length l. f Subtract 2 times the weld height h f , β is the design value for the strength of the vertical fillet weld. f This is the strength design value increase factor for the front fillet weld, and the value is 1.0 for the verification of the lightning rod weld.

[0375] It should be noted that, Figure 14 The "specific operation result of two values" in the above formula refers to the result of the operation of two values. A simplified description is provided to concisely represent the flowchart.

[0376] Figure 26 This is a flowchart for verifying the horizontal fillet weld of the stiffening plate on the flange. The specific steps include:

[0377] S111, Calculate the maximum shear stress τ generated by the horizontal fillet weld. fh :

[0378]

[0379] S112. Determine the maximum shear stress τ generated by the horizontal fillet weld. fh Does it meet the following relationship:

[0380]

[0381] S113. If the judgment is yes, then the calculation is performed by checking the horizontal fillet weld of the stiffening plate on the flange.

[0382] h eh The effective height of the horizontal fillet weld is equal to 0.7 times the horizontal weld height h. fh , l wh The effective length of the horizontal fillet weld is equal to the actual weld length l. fh Subtract 2 times the weld height h fh , This is the design strength value for horizontal fillet welds.

[0383] The column base of the independent lightning rod adopts a solid web rigid connection. The column base calculation is performed according to Section 13.8 of the "Steel Structure Design Manual" (edited by Dan Zeyi) and in conjunction with the stress characteristics of the lightning rod. The following is a detailed explanation of the calculation for the independent lightning rod.

[0384] Furthermore, when the single-column steel tube lightning rod is an independent lightning rod, the performance calculation method for the single-column steel tube lightning rod also includes:

[0385] Obtain column base parameters, and perform strength verification of column base plate and foundation concrete, shear key calculation, stiffening plate calculation, and anchor bolt design verification based on column base parameters;

[0386] Figure 27 This is a flowchart for calculating the strength of the column base slab and foundation concrete based on column base parameters. The steps include:

[0387] S121. Based on the fifth section pipe diameter d5 and the initially selected anchor bolt diameter d M Initial determination of the outer diameter d of the column base plate b Calculate the outer edge distance a of the anchor bolt hole M and inner margin b M :

[0388] a M =5*(INT(d M +2)*2 / 5)+1)

[0389] b M =5*(INT(dM +2)*2.5 / 5)+1)

[0390] That is, the outer edge distance of the anchor bolt hole should be a multiple of 5 greater than twice the diameter of the anchor bolt hole, and the inner edge distance of the anchor bolt hole should be a multiple of 5 greater than 2.5 times the diameter of the anchor bolt hole.

[0391] S122, Based on the outer edge distance a of the anchor bolt hole M and inner margin b M Calculate the outer diameter d of the column base plate b :

[0392] d b =d5+2a M +2b M

[0393] Verify the maximum compressive stress σ in the column base concrete. 1 max The specific steps include:

[0394] S123. Calculate the maximum compressive stress σ in the column base concrete. 1 max :

[0395]

[0396] S124. Determine the maximum compressive stress σ in the column base concrete. 1 max Does it meet the following relationship:

[0397] σ 1 max ≤f c

[0398] S125. If the judgment is yes, then the maximum compressive stress of the column base concrete is checked.

[0399] N M The design value of the axial force at the column base is taken as the design value of the axial force at the calculated section of the lower end of the fifth steel pipe segment, A. M M is the cross-sectional area of ​​the column base plate. M The design value of the column base bending moment is taken as the design value of the bending moment at the lower end of the fifth steel pipe section, W. M f is the section modulus of the column base plate. c This is the design value for the axial compressive strength of concrete.

[0400] S126. Calculate the minimum thickness t of the column base plate. min :

[0401]

[0402] M 0 max The value of the bending moment per unit length on the grid plate in the most unfavorable zone under the action of the foundation reaction force is given by f, which is the design value of the tensile strength of the steel in the column base plate, and α1 is the steel strength reduction factor, which is taken as 0.7 for a single-column steel tube lightning rod.

[0403] In addition, the thickness of the column base plate, besides being determined according to the above calculations, should also meet the structural requirements, that is, the thickness of the base plate should not be less than 25mm and should not be greater than 100mm.

[0404] S127. Calculate the maximum bending moment M per unit length on the grid plate in the most unfavorable zone of the column base plate. 0 max :

[0405]

[0406] σ c The average stress of the concrete at the bottom of the grid plate in the most unfavorable zone is calculated according to formula (5). β2 is a parameter pre-set according to b2 / a2. For details of the setting, please refer to Table 8. a2 and b2 are the length of the free side of the plate and the side length of the adjacent side.

[0407]

[0408]

[0409] Table 8

[0410] The steps for calculating shear keys based on column base parameters include:

[0411] Calculate the embedment depth h of the shear key j , where h j =1.45V j / f c b j +h j0 V j h is the design value of the column base shear force. j0 For ineffective burial depth, take twice the thickness of the column base plate, b j This represents the width of the shear key.

[0412] The welds between the shear key and the column base plate should be welded with equal strength.

[0413] Lightning rod column base anchors should not bear the horizontal reaction force at the bottom of the column base. The horizontal force at the column base is first transferred to the foundation concrete through the friction between the column base plate and the concrete contact surface. However, if this horizontal force is greater than the friction at the contact surface, shear keys are required to resist the horizontal force. Commonly used shear keys are I-beams or square steel, welded to the bottom of the column base plate. The horizontal force at the column base is transferred from the base plate to the shear key, and then from the shear key to the surrounding concrete. Therefore, the effective contact area between the shear key and the concrete is crucial for the shear key to transfer sufficient horizontal force. The width b of the shear key... j One-quarter of the diameter of the fifth section of the steel pipe can be used.

[0414] The calculation steps for the stiffening plate of the column base plate are basically the same as those for the stiffening plate of the flange, but the internal forces on the stiffening plate are obtained from the foundation reaction force.

[0415] Figure 28 This is a flowchart of stiffening plate calculation based on column base parameters, and its steps include:

[0416] S131. Draw the foundation reaction diagram, determine the length x of the compressive stress distribution on one side of the foundation slab, and determine the compressive stress σ at the outer diameter edge of the column caused by the foundation reaction. 2 max ;

[0417] S132. Calculate the foundation reaction force within the bottom plate section borne by the stiffening plate section:

[0418]

[0419]

[0420] It should be noted that V S M is the shear force generated in the stiffening plate due to the foundation reaction force within the base plate section. S The bending moment generated in the stiffening plate due to the foundation reaction force within the base plate section.

[0421] The specific steps for performing strength verification of the stiffening plate at the column base include:

[0422] S133. Calculate the maximum shear stress τ in the stiffening plate of the column base plate. s and the maximum normal stress value σ of the stiffening plate of the column base plate s :

[0423]

[0424]

[0425] S134. Determine the maximum shear stress τ of the stiffening plate at the column base. s and the maximum normal stress value σ of the stiffening plate of the column base plate s Do they all meet the following relationship:

[0426] τ s ≤α1f ν

[0427] σ s ≤α1f

[0428] S135. If the judgment is yes, then the strength of the stiffening plate of the column base plate shall be verified.

[0429] h j The effective height of the stiffening plate at the column base plate is given. For stiffening plates with chamfers, the chamfer height must be subtracted. j For the stiffening plate thickness of the column base plate, f ν σ is the design value of the shear strength of the stiffening plate at the column base. sdenoted as , where is the maximum normal stress value of the stiffening plate at the column base, and f is the design value of the tensile strength of the stiffening plate at the column base.

[0430] S136. Perform weld verification on the stiffening plate of the column base plate. The steps include:

[0431] Perform verification calculations on the vertical fillet welds of the stiffening plates at the column base plate.

[0432] Perform verification calculations for the horizontal fillet welds of the stiffening plates at the column base.

[0433] The two steps described above will be explained in detail below.

[0434] Figure 29 This is a flowchart for verifying the vertical fillet welds of the stiffening plates at the column base. The specific steps include:

[0435] S141. Calculate the maximum shear stress τ generated by the vertical fillet weld. f and the maximum normal stress σ generated by the vertical fillet weld. f :

[0436]

[0437]

[0438] S142. Determine whether the maximum shear stress and the maximum normal stress generated by a vertical fillet weld both conform to the following relationship:

[0439]

[0440]

[0441]

[0442] S143. If the judgment is yes, then the calculation is performed by checking the vertical fillet weld of the stiffening plate of the column base plate.

[0443] h e The effective height of the vertical fillet weld is equal to 0.7 times the weld height h. f , l w The effective length of the vertical fillet weld is equal to the actual weld length l. f Subtract 2 times the weld height h f , β is the design value for the strength of the vertical fillet weld. f The strength design value of the fillet weld is increased by a factor of 1.0 for the verification of the lightning rod weld.

[0444] Figure 30 This is a flowchart for verifying the horizontal fillet weld of the stiffening plate at the column base. The specific steps include:

[0445] S151. Calculate the maximum shear stress τ generated by the horizontal fillet weld. fh :

[0446]

[0447] S152. Determine the maximum shear stress τ generated by the horizontal fillet weld. fh Does it satisfy the following relationship:

[0448]

[0449] S153. If the judgment is yes, then the calculation is performed by checking the horizontal fillet weld of the stiffening plate of the column base plate.

[0450] h eh The effective height of the horizontal fillet weld is equal to 0.7 times the horizontal weld height h. fh , l wh The effective length of a horizontal fillet weld is equal to the actual weld length l. fh Subtract 2 times the weld height h fh , This is the design strength value for horizontal fillet welds.

[0451] Figure 31 This is a flowchart of anchor bolt design verification based on column base parameters, and its steps include:

[0452] S161, Set bending moment M M The design value of the bending moment at the bottom of the fifth steel pipe section (partial factor is 1.5), and the axial force N. M The standard value of the axial force at the bottom of the fifth section of the steel pipe (partial factor is 1.0);

[0453] The most unfavorable combination of internal forces for anchor bolts is the maximum bending moment and the minimum axial pressure, which results in the maximum tensile stress on the base plate.

[0454] Figure 32 This is a simplified diagram for anchor bolt calculation.

[0455] S162, Calculate M M N M The maximum compressive stress σ under action max The hypothetical maximum tensile stress σ min The compressive stress distribution length x and eccentricity e on one side of the bottom of the plate = M M / N M :

[0456]

[0457]

[0458] B is the width of the column base plate, and L is the length of the column base plate.

[0459] like Figure 32 As shown, based on the maximum compressive stress σ on one side of the base plate max And the hypothetical maximum tensile stress σ on the other side min Find the length x of the compressive stress distribution on one side of the base plate. It should be noted that the solution process is as follows: the length x of the compressive stress distribution on one side of the base plate is the total length of the horizontal axis corresponding to the compressive stress, i.e., the negative stress; the maximum compressive stress σ on one side of the base plate... max Using the flange's outer diameter as the vertical axis and the outer diameter as the horizontal axis, the first coordinate point is formed. The other side represents the hypothetical maximum tensile stress σ. min Using the vertical coordinate and the value of 0 as the horizontal coordinate, a second coordinate point is formed. Based on the two coordinate points, a linear function equation is obtained regarding the length x of the compressive stress distribution on one side of the base plate, thus obtaining the length x of the compressive stress distribution on one side of the base plate.

[0460] S163. Calculate the effective cross-sectional area A of a single anchor bolt. c :

[0461]

[0462] e>(d b / 6+x / 3)

[0463] n i Here, represents the number of anchor bolts on one side of the column base, 'e' represents the eccentricity, and 'c' represents the distance from the outer edge of the anchor bolts at the column base. β is the design value of the tensile strength of the anchor bolt. x The tolerance factor for anchor bolt corrosion can be taken as 1.1.

[0464] When the eccentricity e≤d b / 6 or d b / 6 <e≤(d b When the anchor bolts are in the tensile side (6+x / 3), the anchor bolts on the tensile side shall be installed according to the structural requirements.

[0465] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for calculating the performance of a single-column steel tube lightning rod, characterized in that, include: Obtain the load parameters, and perform load combination calculation, gravity load calculation, wind load calculation, and internal force standard value calculation on the single-column steel tube lightning rod based on the load parameters; Obtain component parameters, and perform component strength verification, component deformation verification, and component stability verification on single-column steel tube lightning rods based on the component parameters; Obtain the connection parameters, and perform flange bolt strength verification, flange plate strength verification, stiffening plate strength verification, and stiffening plate weld verification on the single-column steel tube lightning rod based on the connection parameters. Real-time monitoring of single-column steel tube lightning rods is conducted based on calculation and verification results.

2. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 1, characterized in that, The single-column steel pipe lightning rod types include frame lightning rods and independent lightning rods; The lightning rod structure is divided into five sections, of which the first and second sections are combined to form the tip section, the third and fourth sections are combined to form the middle section, and the fifth section is the grounding pole section. The independent lightning rod is divided into five sections, of which the first and second sections are combined to form the tip section, and the third, fourth and fifth sections are combined to form the non-tip section.

3. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 2, characterized in that, The steps for performing load combination calculations on single-column steel tube lightning rods based on the load parameters include: The strength and stability of the needle tip segment were verified, wherein S d =1.0 S Gk +1.0 S Wk ; The strength and stability of the middle section and the non-needle tip section were verified. Specifically, under unfavorable gravity load conditions, S... d =1.3 S Gk +1.5 S Wk When gravity load is favorable, S d =1.0 S Gk +1.5 S Wk ; Deformation calculations were performed on the middle section and the non-needle tip section, where S d = S Gk +0.5 S Wk ; The strength and stability of the grounding wire segment were verified, including under unfavorable gravity load conditions, S d =1.3 S Gk +1.5 S Wk +1.4 S Dk When gravity load is favorable, S d =1.0 S Gk +1.5 S Wk +1.4 S Dk ; The deformation of the grounding wire segment is verified, where S d = S Gk +0.5 S Wk + S Dk ; S Gk These are the standard values ​​for the gravity load effect of each section of the steel pipe. S Wk These are the standard values ​​for the wind load effect on each section of the steel pipe. S Dk This represents the standard value of the ground wire load effect.

4. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 2, characterized in that, The steps for calculating gravity load, wind load, and standard internal force values ​​of a single-column steel tube lightning rod based on the load parameters include: Calculate the gravity load G of each section of the steel pipe. k0 Among them, G k0 =g k l,g k Let l be the standard value of gravity load per unit length of each steel pipe segment, and l be the unit length of each steel pipe segment. The correction value G for the gravity load of each steel pipe segment is calculated based on the gravity load of each segment. k Among them, G k =αG k0 G k0 α represents the standard value of the gravity load of each section of the steel pipe, and α is the correction factor for the gravity load of the lightning rod. Calculate the standard value of wind load w for each section of steel pipe k and the standard value of wind load line load W for each section of steel pipe k , where w k =α h β z μ s μ z w0, W k =w k d, α h β is the basic wind pressure amplification factor for tall structures. z For the wind vibration coefficient at a specific altitude, μ s Let μ be the wind load shape coefficient for each section of the steel pipe. z The wind pressure height variation coefficient for each section of the steel pipe at a specific height, w0 is the basic wind pressure, and d is the pipe diameter of each section of the steel pipe; Calculate the standard value of axial force N at the calculated cross-section of each section of the steel pipe. k ,in, Calculate the standard value of shear force V caused by wind load at the calculated cross section of each steel pipe segment. wk ,in, Calculate the standard value of shear force V of the calculated cross section of the ground wire column steel pipe caused by the ground wire load. Dk ,in, V Dk =T Dk Calculate the standard value M of the bending moment caused by wind load at the calculated cross section of each steel pipe segment. wk ,in, Calculate the standard value of the bending moment M caused by the ground wire load on the calculated cross section of the steel pipe section of the ground wire column. Dk ,in, M Dk =T DK l 5 T DK For the ground wire load, l i Let be the length of the i-th segment of the steel pipe. Let be the standard value of the wind load line load for the i-th segment of the steel pipe.

5. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 4, characterized in that, The steps for performing component strength verification on a single-column steel tube lightning rod based on component parameters include: The structural strength of the single-column steel tube lightning rod was verified: For each section of an independent lightning rod and the first to fourth sections of a frame lightning rod, The fifth section of the lightning rod in the structure, N The design values ​​of axial force were calculated for the cross-sectional strength and stability verification of each section of the steel pipe. A n Calculate the net cross-sectional area of ​​each section of the steel pipe. M x The design bending moment value is verified for the cross-sectional strength of each section of the steel pipe. γ x The coefficient for plastic development of the cross section. W nx Calculate the net section modulus of each section of the steel pipe. The strength reduction factor for each section of steel is... f These are the design values ​​for the tensile strength of the steel in each section of the steel pipe. γ G For gravity load partial factor, γ W This is the wind load partial factor. γ D This is the partial factor for ground wire load.

6. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 5, characterized in that, The steps for performing component deformation verification of a single-column steel tube lightning rod based on component parameters include: The load bending moment diagrams of the third to fifth steel pipe sections are divided into three types according to the number of pipe sections: rectangular, triangular, and parabolic. The area and centroid position of each type are calculated, and the unit bending moment value corresponding to each centroid position is obtained, as detailed below: Regarding the third paragraph: Regarding the fourth paragraph: Regarding the fifth paragraph: For the third to fifth sections of independent lightning rods and the third to fourth sections of frame lightning rods: The fifth section of the lightning rod structure: This represents the total area of ​​the rectangular portion in the bending moment diagram for each section of the steel pipe under various loads. This represents the total area of ​​the triangular portion in the bending moment diagram for each section of the steel pipe under various loads. This represents the total area of ​​the parabolic portion in the bending moment diagram for each section of the steel pipe under various loads. This represents the unit bending moment value corresponding to the centroid coordinates of the rectangular area in the bending moment diagram for each section of the steel pipe under each load. This represents the unit bending moment value corresponding to the centroid coordinates of the triangle area in the bending moment diagram for each section of the steel pipe under each load. This represents the unit bending moment value corresponding to the centroid coordinates of the parabolic area in the bending moment diagram for each section of the steel pipe under each load. l The length of each section of steel pipe, I Calculate the moment of inertia of each section of the steel pipe. E The elastic modulus of the steel in each section of the steel pipe. V q The shear force values ​​at the vertices of each steel pipe section are calculated based on the quasi-permanent combination. This is the quasi-permanent value coefficient for wind load. W q The wind load line load values ​​for each section of steel pipe calculated according to the quasi-permanent combination. M q The bending moment values ​​at the apex sections of each steel pipe are calculated based on the quasi-permanent combination. This is the quasi-permanent value coefficient for ground wire load. H u This refers to the total length of the third to fifth sections of the steel pipe.

7. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 6, characterized in that, The steps for performing component stability verification on a single-column steel tube lightning rod based on component parameters include: Perform diameter-to-thickness ratio verification: d / t≤ 100 （ 235 / fy) t is the wall thickness of each section of the steel pipe, and fy is the yield strength of the steel in each section of the steel pipe; Stability calculations were performed on the lowest cross-sections of the steel pipes of the third to fifth sections of independent lightning rods subjected only to wind loads, and the third and fourth sections of frame lightning rods. This is the correction factor for the axial force stress component. This is the equivalent bending moment coefficient. The design values ​​of the bending moment for stability verification of each section of the steel pipe are calculated. The design value of axial force is calculated to verify the stability of the cross-section of each steel pipe segment. Calculate the gross section modulus of each section of the steel pipe. For the stability calculation parameters of each section of the steel pipe, A Calculate the cross-sectional area for each section of the steel pipe. The slenderness ratio of each section of the steel pipe, This refers to the length used in the overall stability check of the cross-sections of each steel pipe section under wind load. Calculate the radius of gyration of the cross section for each section of the steel pipe; Stability calculations were performed on the fifth section of the lightning rod in the structure: This is the correction factor for the axial force stress component. This is the equivalent bending moment coefficient. The design value of the bending moment for stability verification of the calculated section caused by wind load. The design value of the bending moment for stability verification of the calculated section caused by the ground wire load. Stability calculation parameters caused by wind load These are the stability calculation parameters caused by the ground wire load. This refers to the length used in the overall stability verification of the fifth section of the steel pipe under ground wire load.

8. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 7, characterized in that, The steps for verifying the flange bolt strength of a single-column steel tube lightning rod based on the connection parameters include: Calculate the tensile force of the lightning rod flange bolts : Determine the tensile force of the lightning rod flange bolts Does it satisfy the following relationship: If the determination is yes, then the strength of the flange bolts is checked; These are the design values ​​for the bending moment at the flanges of each section of the steel pipe. These are the design values ​​for the axial force at the flanges of each section of the steel pipe. This is the distance from the bolt center to the axis of rotation. This is the distance from the center of the bolt under maximum stress to the axis of rotation. n This refers to the number of bolts on the flange. This is the design value for the tensile bearing capacity of a bolt. This is the effective diameter of the bolt at the thread. This is the design value for the tensile strength of the bolt; The step of performing flange strength verification based on the connection parameters includes: Calculate the uniformly distributed load on the grid plates divided by the stiffening plate and the outer wall of the steel pipe. : The length of the free side of the grid plate. This is the side length of the grid plate adjacent to the free edge; Calculate the bending moment of the sections divided by the stiffening plate and the outer wall of the steel pipe. : According to The preset parameter is the ratio coefficient of the side length of the grid plate; Calculate the bending moment values ​​of the sections divided by the stiffening plate and the outer wall of the steel pipe. : This is the design value for the tensile strength of the flange plate; The step of verifying the strength of the stiffening plate based on the connection parameters includes: Calculate the maximum shear stress value of the stiffened plate and the maximum normal stress value of the stiffening plate : Determine the maximum shear stress value of the stiffening plate. and the maximum normal stress value of the stiffening plate Do they all satisfy the following relationship: If the determination is yes, then the strength of the stiffening plate on the flange is checked; For the height of the stiffening plate, For stiffening plate thickness, This represents the design value of the shear strength of the stiffening plate. This is the distance from the center line of the bolt hole to the outer wall of the steel pipe. This is the design value for the tensile strength of the stiffening plate; The step of verifying the stiffening plate weld based on the connection parameters includes: The specific steps for verifying the vertical fillet weld of the stiffening plate on the flange include: Calculate the maximum shear stress generated by the vertical fillet weld. and the maximum normal stress generated by vertical fillet welds : Determine the maximum shear stress generated by the vertical fillet weld. and the maximum normal stress generated by vertical fillet welds Does it meet the following relationship: If the determination is yes, then the calculation is performed by checking the vertical fillet weld of the stiffening plate on the flange; Effective height of vertical fillet weld Effective length of vertical fillet weld This is the design value for the strength of the vertical fillet weld. This is an increase factor for the strength design value of the front fillet weld; The specific steps for verifying the horizontal fillet weld of the stiffening plate on the flange include: Calculate the maximum shear stress generated for the horizontal fillet weld. : Determine the maximum shear stress generated by the horizontal fillet weld. Does it meet the following relationship: If the determination is yes, then the calculation is performed by checking the horizontal fillet weld of the stiffening plate on the flange; The effective height of the horizontal fillet weld is equal to 0.7 times the height of the horizontal weld. , The effective length of the horizontal fillet weld is equal to the actual length of the weld. Subtract 2 times the weld height , This is the design strength value for horizontal fillet welds.

9. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 2, characterized in that, When the single-column steel tube lightning rod is an independent lightning rod, the performance calculation method for the single-column steel tube lightning rod further includes: Obtain column base parameters, and perform strength verification of column base plate and foundation concrete, shear key calculation, stiffening plate calculation and anchor bolt design verification based on the column base parameters; The steps for verifying the strength of the column base plate and foundation concrete based on the column base parameters include: Based on the fifth section pipe diameter d5 and the initially selected anchor bolt diameter d M Initial determination of the outer diameter d of the column base plate b Calculate the outer edge distance a of the anchor bolt hole M and inner margin b M : a M =5 (INT((d M +2) 2 / 5)+1) b M =5 (INT((d M +2) 2.5 / 5)+1) According to the outer edge distance a of the anchor bolt hole M and inner margin b M Calculate the outer diameter d of the column base plate b : d b =d5+2a M +2b M Verify the maximum compressive stress in the column base concrete. The specific steps include: Calculate the maximum compressive stress in the concrete at the column base. : Determine the maximum compressive stress in the column base concrete. Does it meet the following relationship: If the determination is yes, then the maximum compressive stress of the column base concrete is checked; N M The design value of the axial force at the column base is taken as the design value of the axial force at the calculated section of the lower end of the fifth steel pipe segment. A M The cross-sectional area of ​​the column base plate is... M M The design value of the column base bending moment is taken as the design value of the bending moment at the lower end of the fifth steel pipe section. W M The section modulus of the column base plate. f c This is the design value for the axial compressive strength of concrete. Calculate the minimum thickness of the column base plate t min : This represents the maximum bending moment per unit length in each section of the column base plate. This is the design value for the tensile strength of the steel in the column base plate. This is the steel strength reduction factor; Calculate the maximum bending moment per unit length in each section of the column base plate. : in, The average stress of the concrete at the bottom of the grid slab in the most unfavorable zone. According to Preset parameters a 2. b 2 represents the length of the free side of the plate and the length of the adjacent side.

10. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 9, characterized in that, The step of calculating the shear key based on the column base parameters includes: Calculate the embedment depth of the shear key h j ,in, , This is the design value for the column base shear force. To avoid ineffective embedment depth, the welds between the shear key and the column base plate should be welded with equal strength. b j This represents the width of the shear key.

11. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 10, characterized in that, The step of calculating the stiffening plate based on the column base parameters includes: Draw the reaction force diagram of the foundation slab and determine the compressive stress distribution length on one side of the foundation slab. x The value is calculated, and the compressive stress at the outer diameter edge of the column caused by the foundation reaction is obtained. ; Calculate the foundation reaction force borne by the stiffening plate section within the base plate grid: The specific steps for performing strength verification of the stiffening plate at the column base include: Calculate the maximum shear stress value of the stiffening plate at the column base. and the maximum normal stress value of the stiffening plate of the column base plate : Determine the maximum shear stress value of the stiffening plate of the column base plate. and the maximum normal stress value of the stiffening plate of the column base plate Do they all meet the following relationship: If the determination is yes, then the strength of the stiffening plate of the column base plate is checked; Effective height of the stiffening plate for the column base plate. Thickening the stiffening plate of the column base plate. Design value of shear strength of stiffening plate at column base. This represents the maximum normal stress value of the stiffening plate at the column base. The design value of the tensile strength of the stiffening plate for the column base plate; Perform verification calculations on the stiffening plate welds of the column base plate; The steps for verifying the weld seam of the stiffening plate at the column base include: Perform verification calculations on the vertical fillet welds of the stiffening plates at the column base plate. Perform verification calculations for the horizontal fillet welds of the stiffening plates at the column base plate; The specific steps for verifying the vertical fillet weld of the stiffening plate at the column base include: Calculate the maximum shear stress generated by the vertical fillet weld. and the maximum normal stress generated by vertical fillet welds : Determine whether the maximum shear stress and the maximum normal stress generated by the vertical fillet weld both conform to the following relationship: If the determination is yes, then the calculation is performed by checking the vertical fillet weld of the stiffening plate of the column base plate; The effective height of the vertical fillet weld. The effective length of the vertical fillet weld. This is the design strength value for vertical fillet welds. This is an increase factor for the strength design value of the front fillet weld; The specific steps for verifying the horizontal fillet weld of the stiffening plate at the column base include: Calculate the maximum shear stress generated for the horizontal fillet weld. : Determine the maximum shear stress generated by the horizontal fillet weld. Does it satisfy the following relationship: If the determination is yes, then the calculation is performed by checking the horizontal fillet weld of the stiffening plate of the column base plate; The effective height of the horizontal fillet weld. The effective length of the horizontal fillet weld. This is the design strength value for horizontal fillet welds.

12. The method for calculating the performance of a single-column steel tube lightning rod as described in claim 11, characterized in that, The steps for anchor bolt design verification based on the column base parameters include: Setting bending moment The design value for the bending moment at the bottom of the fifth steel pipe section, and the axial force. This is the standard value of the axial force at the bottom of the fifth section of the steel pipe; calculate , Maximum compressive stress under action Imaginary maximum tensile stress Length of compressive stress distribution on one side of the bottom of the plate x and eccentricity e = / : The width of the column base plate. The length of the column base plate; Based on the maximum compressive stress on one side of the base plate And the hypothetical maximum tensile stress on the other side Determine the length x of the compressive stress distribution on one side of the base plate; Calculate the effective cross-sectional area of ​​a single anchor bolt : e >( d b / 6+ x / 3) 'e' represents the number of anchor bolts on one side of the column base, and 'e' represents the eccentricity. c This refers to the outer distance of the column base anchor bolt. This is the design value for the tensile strength of the anchor bolt. This is the tolerance factor for anchor bolt corrosion.

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