A method for calculating the bearing capacity of a power transmission tower angle steel after non-destructive reinforcement

Abstract

The present application relates to the technical field of power transmission tower angle steel bearing capacity calculation, in particular to a kind of power transmission tower angle steel bearing capacity calculation method after nondestructive reinforcement;It includes the limit bearing capacity Bc ultimate Corresponding to the calculation of different repair finite element model And repair wind load Wl repair ; Limit bearing capacity Bc ultimate And repair wind load Wl repair Numerical state, select the appropriate repair reinforcement method.The present application obtains the corresponding reference value by simulating the repair finite element model under different repair reinforcement methods, and compares with the corresponding conventional reference data, calculates the final matching rate, matches the best repair reinforcement method for different defects, and improves the simulation effect.

Description

Technical Field

[0001] This invention relates to the field of load-bearing capacity calculation technology for angle steel of transmission towers, and more specifically, to a method for calculating the load-bearing capacity of angle steel of transmission towers after non-destructive reinforcement. Background Technology

[0002] With continuous economic development, people's demand for electricity is increasing day by day. To meet this demand, power companies have built a large number of transmission lines. Transmission towers are the arteries of the power system and a fundamental guarantee for the successful transmission of electrical energy. Therefore, ensuring the safe and stable operation of the power transmission system is of paramount importance. There are many types of transmission towers, mainly divided into horn-shaped, T-shaped, and F-shaped types.

[0003] Traditional transmission towers are mostly made of angle steel structures, which are connected and fixed by welding, bolts and clamps. Since the transmission towers are outdoors, they are exposed to wind and sun, and their exposed parts are easily damaged, such as cracks, fissures or gaps in the angle steel. At this time, it is necessary to use flaw detection to help determine the damaged area and the undamaged area.

[0004] For damage such as cracks or gaps, the main repair method is welding. Alternatively, friction-type high-strength bolts and high-strength steel pads can be used to balance the shear force and the friction force distributed along the surface of the pads and angle steel. After repair, the shape is ground to be the same as the original tower material.

[0005] For minor cracks, high-strength steel pads are bonded to both the inner and outer sides of the angle steel using a steel-adhesive layer. This method effectively reduces the stress level of the steel in the damaged area, improves the stress state in the defect area, inhibits the development of potential damage inside the steel during long-term operation, and ensures the reliability of the joint connection during long-term operation.

[0006] Therefore, there are various non-destructive repair methods that can be used for different types of damage, but the actual effects of different non-destructive repair methods are different, and the degree to which they affect the load-bearing capacity and wind load of the transmission tower also varies.

[0007] To address the aforementioned issues, a method for calculating the load-bearing capacity of transmission tower angle steel after non-destructive reinforcement is urgently needed. Summary of the Invention

[0008] The purpose of this invention is to provide a method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement, so as to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, a method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement is provided, comprising the following steps:

[0010] S1. Based on the structural drawing of the transmission tower to be tested, obtain the installation position of each angle steel component, and simulate the finite element model of the transmission tower to be tested using ANSYS finite element software.

[0011] S2. Obtain images of damaged angle steel components of the transmission tower under test, combine them with the damaged image database to determine the damage type of the damaged angle steel components of the transmission tower, and locate the position of the damaged angle steel components by combining them with the construction structure diagram of the transmission tower under test in S1.

[0012] S3. Collect data on the wind force changes experienced by the damaged angle steel component in the actual environment, simulate the corresponding wind force changes using ANSYS finite element software, and calculate the normal wind load Wl on the damaged angle steel component before it was damaged. conventional and conventional load-bearing capacity Bc conventional ;

[0013] S4. Based on the damage type of the damaged angle steel component of the transmission tower determined in S2, match the corresponding repair and reinforcement method;

[0014] S5. Simulate the finite element model of the repair after different repair and reinforcement methods using ANSYS finite element software;

[0015] S6. Calculate the ultimate bearing capacity Bc corresponding to different repair finite element models. ultimate And repair wind load Wl repair ;

[0016] S7, combined with ultimate bearing capacity Bc ultimate And repair wind load Wl repair Based on the numerical status, select the appropriate repair and reinforcement method.

[0017] As a further improvement to this technical solution, the method for simulating the finite element model of the transmission tower under test using ANSYS finite element software in step S1 includes the following steps:

[0018] S1.1 Select the three-dimensional beam element BEAM188 to simulate the main material and cross diagonal members of the transmission tower, obtain the tensile, compressive, torsional and shear force data of the main material and cross diagonal members in the transmission tower, record the deformation of the transmission tower under different conditions into the model system, set the single-sided constraints at different ends of the transmission tower, and ensure that the construction direction of the angle steel material of the transmission tower meets the actual design requirements.

[0019] S1.2 Select the two-dimensional tension and compression unit LINK180 to simulate the auxiliary materials of the transmission tower, and input the tension and compression data of the auxiliary materials of the transmission tower into the model system;

[0020] S1.3 Select a node coupling method to simulate the cross-braced connecting bolts set in the transmission tower, so that the linear displacement of the transmission tower support node is the same in different directions;

[0021] S1.4 Set translational and rotational degrees of freedom in different directions as constraints to simulate the connection between the foundation and support of the transmission tower;

[0022] S1.5 Apply wind load directly to the support nodes of the transmission tower to simulate the stress changes of the conductors and nodes in the transmission tower.

[0023] S1.6 Using the constructed transmission tower model, simulate the changes in the foundation displacement of the transmission tower caused by ground deformation and ground movement, and set the constraints for the rotation of the transmission tower.

[0024] As a further improvement to this technical solution, the method for determining the damage type of the damaged angle steel component of the transmission tower in step S2 includes the following steps:

[0025] S2.1. Based on the acquired images of the damaged angle steel components of the transmission tower under test, determine the damaged area of ​​the angle steel components;

[0026] S2.2 Damage located at the edge of the angle steel component is marked as notch damage G. damage The damage type located on the surface of the angle steel component is marked as crack damage C. damage and cracked Cr damage ;

[0027] S2.3. Based on the image of the damaged angle steel component, determine the type of damage (C) caused by cracks. damage and crack damage Cr damage Damaged length Le damage and damaged width Wi damage ;

[0028] S2.4 Define the crack damage length range C led C, the range of crack damage wid , Crack damage length range Cr led and the range of crack damage Cr wid C, damaged by splitting patterns damage and crack damage Cr damage .

[0029] As a further improvement to this technical solution, the S2.4 middle region splitting crack damage C damage and crack damage Cr damage The method includes the following steps:

[0030] S2.4.1 Calculate the damage length Le of the current damaged area. damage and maximum damage width Wi damage ;

[0031] S2.4.2 Determine the damage length Le damage and maximum damage width Wi damage Location;

[0032] When the damage length Le damage ∈ Crack damage length range Cr led Or the bandwidth is damaged. damage ∈ Crack damage width range Cr wid The current damage type is marked as crack damage;

[0033] When the damage length Le damage ∈ C crack damage length range led And the maximum damage width Wi damage ∈ C crack damage width range C wid The current damage type is marked as crack damage.

[0034] As a further improvement to this technical solution, the conventional wind load Wl in S3 conventional The calculation uses a wind load calculation algorithm, and the algorithm formula is as follows:

[0035] Wl conventional =ω0·μ z μ s ·β z ·S f ;

[0036] β z =1+δε1ε2;

[0037] Where ω0 is the standard value of wind load on the transmission tower, μ z Let μ be the wind pressure height variation coefficient at height z. s β is the basic wind pressure coefficient. z S is the wind vibration coefficient at height z. f ε is the projected area of ​​the angle steel member under wind load, ε1 is the coefficient affected by wind pressure height and wind pressure pulsation, ε2 is the coefficient affected by the shape of the angle steel structure and vibration mode, and δ is the pulsation amplification coefficient.

[0038] As a further improvement to this technical solution, the conventional bearing capacity Bc is calculated in step S3. conventional The method includes the following steps:

[0039] S3.1. Using the finite element model, obtain the stress state of angle steel at different heights;

[0040] S3.2 Simulate different wind speeds and directions to obtain the conventional wind load Wl on angle steel components at different heights. conventional Maximum compressive stress Cs maximum Maximum tensile stress Ts maximum and maximum displacement Dis maximum Marked as the regular reference value Ma rate ;

[0041] S3.3. Based on the data acquired in S3.2, create a table corresponding to the acquired data and draw a simulation graph;

[0042] S3.4, Use the acquired data as the standard load-bearing capacity Bc conventional The parameter values ​​are determined, and the corresponding weights are defined based on the rate of change of each acquired data item. The weights are directly proportional to the rate of change.

[0043] As a further improvement to this technical solution, the method for selecting a suitable repair and reinforcement method in step S7 includes the following steps:

[0044] S7.1 Obtain various data under different repair and reinforcement methods;

[0045] S7.2, and compare it with the conventional reference data in S3.2, determine the difference between each acquired data and the corresponding conventional reference data, and mark it as the repair difference Re. difference ;

[0046] S7.3, Establish the repair difference range for various routine reference data (Reg) difference Determine the repair difference range within different wind directions. difference Repair difference Re difference Marked as matching rate Ma ratio ;

[0047] S7.4 Compare the matching rate Ma of each repair and reinforcement method. ratio The repair and reinforcement method with the highest matching rate will be selected as the appropriate repair and reinforcement method.

[0048] As a further improvement to this technical solution, the matching rate Ma in S7.3 ratio The acquisition uses a matching selection algorithm, the formula of which is as follows:

[0049] |Ac value -Ma rate |=Re difference ;

[0050]

[0051] Among them, Ac value Ma represents the actual parameter data obtained through simulation using repair and reinforcement methods. rate For general reference values, Re difference To repair the difference, Reg difference To repair the difference range, F(Ma) is the matching function.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0053] In the method for calculating the bearing capacity of the angle steel of the transmission tower after non-destructive reinforcement, the corresponding reference values ​​are obtained by simulating the finite element model of the repair under different repair and reinforcement methods, and compared with the corresponding conventional reference data to calculate the final matching rate. This method matches the best repair and reinforcement method for different defects and improves the simulation effect. Attached Figure Description

[0054] Figure 1 This is a flowchart illustrating the overall method steps of the present invention;

[0055] Figure 2 The method steps of the present invention for simulating the finite element model of the transmission tower under test using ANSYS finite element software are shown in the figure.

[0056] Figure 3 This is a step diagram illustrating the method for determining the damage type of a damaged angle steel component of a transmission tower according to the present invention;

[0057] Figure 4 For the damaged C of the splitting pattern in the present invention damage and crack damage Cr damage Method steps diagram;

[0058] Figure 5 The calculation of conventional bearing capacity Bc in this invention conventional Method steps diagram;

[0059] Figure 6 This is a standard reference value table for the present invention;

[0060] Figure 7 This diagram illustrates the steps of selecting a suitable repair and reinforcement method according to the present invention. Detailed Implementation

[0061] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0062] Please see Figures 1-7 As shown, a method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement is provided, including the following steps:

[0063] S1. Based on the structural drawing of the transmission tower to be tested, obtain the installation position of each angle steel component, and simulate the finite element model of the transmission tower to be tested using ANSYS finite element software.

[0064] S2. Obtain images of damaged angle steel components of the transmission tower under test, combine them with the damaged image database to determine the damage type of the damaged angle steel components of the transmission tower, and locate the position of the damaged angle steel components by combining them with the construction structure diagram of the transmission tower under test in S1.

[0065] S3. Collect data on the wind force changes experienced by the damaged angle steel component in the actual environment, simulate the corresponding wind force changes using ANSYS finite element software, and calculate the normal wind load Wl on the damaged angle steel component before it was damaged. conventional and conventional load-bearing capacity Bc conventional ;

[0066] S4. Based on the damage type of the damaged angle steel component of the transmission tower determined in S2, match the corresponding repair and reinforcement method;

[0067] S5. Simulate the finite element model of the repair after different repair and reinforcement methods using ANSYS finite element software;

[0068] S6. Calculate the ultimate bearing capacity Bc corresponding to different repair finite element models. ultimate And repair wind load Wl repair ;

[0069] S7, combined with ultimate bearing capacity Bc ultimate And repair wind load Wl repair Based on the numerical status, select the appropriate repair and reinforcement method.

[0070] In practical application, corresponding non-destructive reinforcement methods are planned for transmission towers under different damage states. First, based on the construction structure diagram of the transmission tower to be tested, the construction structure of the transmission tower, the shape and structure of each angle steel, and the connection method and connection part with adjacent angle steel are determined. The installation position of each angle steel component is obtained, and the finite element model of the transmission tower to be tested is simulated using ANSYS finite element software. Then, images of the damaged angle steel components of the transmission tower to be tested are obtained, for example, by taking inspection photos by drones to obtain images of the angle steel structure in different areas of the transmission tower. Combined with the damaged image database, the damage type of the damaged angle steel components of the transmission tower is determined, that is, image comparison is performed to determine the damage type, which is consistent with steel cracks, fissures or notches. Then, combined with the construction structure diagram of the transmission tower to be tested in S1, the location of the damaged angle steel components is located.

[0071] After locating the damaged angle steel component, the wind force changes experienced by the component in the actual environment were collected. ANSYS finite element software was then used to simulate the corresponding wind force changes, and the normal wind load Wl on the damaged angle steel component before it was damaged was calculated. conventional and conventional load-bearing capacity Bc conventional , as reference values ​​for later comparison;

[0072] Since different types of damage can be repaired using various non-destructive repair methods—for example, cracks can be repaired by welding or by using friction-type high-strength bolts and high-strength steel pads—and these two methods result in different repair surfaces, leading to differences in bearing capacity and wind load, selecting the optimal non-destructive repair method requires matching the corresponding repair and reinforcement method to the damage type of the transmission tower's damaged angle steel component determined in S2. This means that each suitable repair method is used, and finite element models of the repairs after different reinforcement methods are simulated using ANSYS finite element software. Subsequently, using the same wind force variation, the corresponding ultimate bearing capacity Bc is calculated. ultimate And repair wind load Wl repair Finally, by combining the ultimate bearing capacity Bc ultimate And repair wind load Wl repair Based on the numerical status, select the appropriate repair and reinforcement method.

[0073] Furthermore, the method for simulating the finite element model of the transmission tower under test using ANSYS finite element software in S1 includes the following steps:

[0074] S1.1 Select the three-dimensional beam element BEAM188 to simulate the main material and cross diagonal members of the transmission tower, obtain the tensile, compressive, torsional and shear force data of the main material and cross diagonal members in the transmission tower, record the deformation of the transmission tower under different conditions into the model system, set the single-sided constraints at different ends of the transmission tower, and ensure that the construction direction of the angle steel material of the transmission tower meets the actual design requirements.

[0075] S1.2 Select the two-dimensional tension and compression unit LINK180 to simulate the auxiliary materials of the transmission tower, and input the tension and compression data of the auxiliary materials of the transmission tower into the model system;

[0076] S1.3 Select a node coupling method to simulate the cross-braced connecting bolts set in the transmission tower, so that the linear displacement of the transmission tower support node is the same in different directions;

[0077] S1.4 Set translational and rotational degrees of freedom in different directions as constraints to simulate the connection between the foundation and support of the transmission tower;

[0078] S1.5 Apply wind load directly to the support nodes of the transmission tower to simulate the stress changes of the conductors and nodes in the transmission tower.

[0079] S1.6 Using the constructed transmission tower model, simulate the changes in the foundation displacement of the transmission tower caused by ground deformation and ground movement, and set the constraints for the rotation of the transmission tower.

[0080] Furthermore, the method for determining the damage type of the damaged angle steel component of the transmission tower in S2 includes the following steps:

[0081] S2.1. Based on the acquired images of the damaged angle steel components of the transmission tower under test, determine the damaged area of ​​the angle steel components;

[0082] S2.2 Damage located at the edge of the angle steel component is marked as notch damage G. damage The damage type located on the surface of the angle steel component is marked as crack damage C. damage and crack damage Cr damage ;

[0083] S2.3. Based on the image of the damaged angle steel component, determine the type of damage (C) caused by cracks. damage and crack damage Cr damage Damaged length Le damage and damaged width Wi damage ;

[0084] S2.4 Define the crack damage length range C led C, the range of crack damage wid , Crack damage length range Cr led and the range of crack damage Cr wid C, damaged by splitting patterns damage and crack damage Cr damage .

[0085] In practical application, when determining the damage type of the angle steel component of a transmission tower, since the images of different damage types are different and their locations also vary, it is first necessary to combine the acquired images of the damaged angle steel component of the transmission tower under test to determine the damaged area of ​​the angle steel component, that is, to determine the location of the damaged area of ​​the angle steel component. When the damaged area is located at the edge of the angle steel component, it is marked as a notch damage G. damage When the damaged area is located on the surface of the angle steel component, there are two possibilities: Crack damage. damage and crack damage Cr damage To distinguish between the two damage types, it is necessary to define the crack damage length range C in advance. led C, the range of crack damage wid , Crack damage length range Cr led and the range of crack damage Cr wid As a region with damaged split lines C damage and crack damage Cr damage Reference standards.

[0086] Furthermore, the splitting cracks in the S2.4 region are damaged (C). damage and crack damage Cr damage The method includes the following steps:

[0087] S2.4.1 Calculate the damage length Le of the current damaged area. damage and maximum damage width Wi damage ;

[0088] S2.4.2 Determine the damage length Le damage and maximum damage width Wi damage Location;

[0089] When the damage length Le damage ∈ Crack damage length range Cr led Or the bandwidth is damaged. damage ∈ Crack damage width range Cr wid The current damage type is marked as crack damage;

[0090] When the damage length Le damage ∈ C crack damage length range led And the maximum damage width Wi damage ∈ C crack damage width range C wid The current damage type is marked as crack damage.

[0091] In practical applications, since the crack area is generally larger than the fissure area, it is necessary to calculate the damage length Le of the current damaged area during the differentiation process. damage and maximum damage width Wi damage And the crack damage length range C led Less than the crack damage length range Cr led C crack damage width range wid Less than the crack damage width range Cr wid Therefore, only when Le damage ∈Cr led Or Wi damage ∈Cr wid Both conditions must be met to classify the current damage type as crack damage. damage ∈C led And Wi damage ∈C wid Both conditions are met, so the current damage type is marked as crack damage.

[0092] Specifically, the conventional wind load Wl in S3 conventional The calculation uses a wind load calculation algorithm, and the algorithm formula is as follows:

[0093] Wl conventional =ω0·μ z μ s ·β z ·S f ;

[0094] βz =1+δε1ε2;

[0095] Where ω0 is the standard value of wind load on the transmission tower, μ z Let μ be the wind pressure height variation coefficient at height z. s β is the basic wind pressure coefficient. z S is the wind vibration coefficient at height z. f ε is the projected area of ​​the angle steel member under wind load, ε1 is the coefficient affected by wind pressure height and wind pressure pulsation, ε2 is the coefficient affected by the shape of the angle steel structure and vibration mode, and δ is the pulsation amplification coefficient.

[0096] It is worth noting that the repair wind load Wl repair The above formula is also used for calculation. During the calculation process, due to the different repair methods used, the projected area S of the angle steel component under wind load is also considered. f The coefficient ε2, which affects the shape and mode shape of the angle steel structure, will change, resulting in a change in S. f The repair wind load Wl corresponding to different repair methods is obtained by calculating ε2 using the formula to be entered. repair This serves as a reference for selecting the best non-destructive repair and reinforcement method in the later stages.

[0097] In addition, the conventional bearing capacity Bc is calculated in S3. conventional The method includes the following steps:

[0098] S3.1. Using the finite element model, obtain the stress state of angle steel at different heights;

[0099] S3.2 Simulate different wind speeds and directions to obtain the conventional wind load Wl on angle steel components at different heights. conventional Maximum compressive stress Cs maximum Maximum tensile stress Ts maximum and maximum displacement Dis maximum Marked as the regular reference value Ma rate ;

[0100] S3.3. Based on the data obtained in S3.2, create a table corresponding to the obtained data and draw a simulation graph;

[0101] S3.4, Use the acquired data as the standard load-bearing capacity Bc conventional The parameter values ​​are determined, and the corresponding weights are defined based on the rate of change of each acquired data item. The weights are directly proportional to the rate of change.

[0102] Due to the conventional load-bearing capacity Bc conventional This solution relates to multiple data points related to angle steel, and incorporates conventional wind load Wl. conventional Maximum compressive stress Cs maximumMaximum tensile stress Ts maximum and maximum displacement Dis maximum As reference data reflecting bearing capacity, these values ​​represent the maximum tolerance range for various parameters under normal conditions. Exceeding these values ​​will lead to the collapse or subsidence of the transmission tower. Even after subsequent repairs and reinforcement, it is necessary to verify the maximum values ​​of each parameter. Figure 6 As shown, the present invention selected an angle steel at a height of 30m for the experiment. When the wind direction changed from 0 degrees to 60 degrees, the conventional wind load Wl was measured. conventional Maximum compressive stress Cs maximum and the maximum displacement Dis maximum All gradually decrease, while the maximum tensile stress Ts maximum As the temperature gradually increases, for example, the rates of change of various parameters from 0 to 30 degrees are as follows:

[0103] Conventional wind load Wl conventional The rate of change: (7541.2-7445.7) / 7541.2 = 1.2%;

[0104] Maximum compressive stress Cs maximum The rate of change: (654-628) / 654 = 3.98%;

[0105] Maximum tensile stress Ts maximum The rate of change: (467-452) / 467 = 3.21%;

[0106] Maximum displacement Dis maximum The rate of change: (784-753) / 784 = 3.95%;

[0107] The results above show that the maximum rate of change is the maximum compressive stress Cs. maximum The rate of change, i.e., under wind conditions of 0-30 degrees, requires the application of the maximum compressive stress Cs. maximum As a reference value for verifying the load-bearing capacity of the angle steel of the transmission tower after non-destructive reinforcement, the maximum compressive stress Cs corresponding to different repair and reinforcement methods needs to be determined during the later verification process. maximum and with the maximum compressive stress Cs maximum The value was compared to 654 MPa to determine the magnitude of the difference.

[0108] It is worth noting that the wind force is positively correlated with all the above reference values, so only wind direction is considered when making comparisons.

[0109] Furthermore, the method for selecting a suitable repair and reinforcement method in S7 includes the following steps:

[0110] S7.1 Obtain various data under different repair and reinforcement methods;

[0111] S7.2, and compare it with the regular reference data in S3.2, determine the difference between each acquired data and the corresponding regular reference data, and mark it as the repair difference Re. difference ;

[0112] S7.3, Establish the repair difference range for various routine reference data (Reg) difference Determine the repair difference range within different wind directions. difference Repair difference Re difference Marked as matching rate Ma ratio ;

[0113] S7.4 Compare the matching rate Ma of each repair and reinforcement method. ratio The repair and reinforcement method with the highest matching rate will be selected as the appropriate repair and reinforcement method.

[0114] Matching rate Ma in S7.3 ratio The acquisition uses a matching selection algorithm, the formula of which is as follows:

[0115] |Ac value -Ma rate |=Re difference ;

[0116]

[0117] Among them, Ac value Ma represents the actual parameter data obtained through simulation using repair and reinforcement methods. rate For general reference values, Re difference To repair the difference, Reg difference To repair the difference range, F(Ma) is the matching function.

[0118] In the specific calculation process, the corresponding parameter values ​​are first obtained by simulating the repaired finite element model using ANSYS finite element software, and then compared with the corresponding conventional reference data. The difference between each obtained data and the corresponding conventional reference data is determined and marked as the repair difference Re. difference To differentiate the matching effects of different repair and reinforcement methods, it is necessary to establish the repair difference range (Reg) for various conventional reference data in advance. difference Determine the repair difference range within different wind directions. difference Repair difference Re difference Marked as matching rate Ma ratio In the later stages, the highest matching rate, Ma, was selected. ratio The repair and reinforcement method is used as an appropriate repair and reinforcement method. For example, under wind conditions of 0-30 degrees, the corresponding conventional reference value Ma can be calculated as follows: rateThe maximum compressive stress Cs maximum The standard value is 654 MPa. At this point, the maximum compressive stress Cs was simulated under different repair and reinforcement methods under wind conditions of 0-30 degrees Celsius. maximum The difference between the pressure and the standard value of 654 MPa is calculated. Three repair and reinforcement methods are proposed, namely A, B, and C. The maximum compressive stress Cs corresponding to method A is... maximum The value is a1, and the maximum compressive stress Cs corresponding to method B is... maximum The value is b1, and the maximum compressive stress Cs corresponding to method B is... maximum The value is c1, and the repair difference Re between methods A, B, and C is... difference The values ​​are a1-654 / MPa, b1-654 / MPa, and c1-654 / MPa, respectively. The repair difference Re is then determined. difference Is it within the repair difference range? (Reg) difference Within, when the repair difference Re corresponding to methods A and B difference Within the repair difference range Reg difference The result indicates that repair and reinforcement methods A and B meet the requirements of conventional repair in the 0-30 degree range, with a matching rate Ma. ratio The matching rate is 100%. Under wind conditions of 0-30 degrees Celsius, repair and reinforcement method A conforms to conventional repair methods, and the matching rate Ma is [missing information]. ratio The matching rate remains at 100%, indicating that repair and reinforcement method B is not suitable. The matching rate Ma at this point is... ratio That is, 50%, until the repair difference Re for all wind directions is completed. difference The assessment task was completed, and the final matching rate (Ma) of different repair and reinforcement methods was obtained. ratio The highest matching rate Ma among them ratio The corresponding repair and reinforcement methods are marked as suitable repair and reinforcement methods.

[0119] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement, characterized in that, Includes the following steps: S1. Based on the structural drawing of the transmission tower to be tested, obtain the installation position of each angle steel component, and simulate the finite element model of the transmission tower to be tested using ANSYS finite element software. S2. Obtain images of damaged angle steel components of the transmission tower under test, combine them with the damaged image database to determine the damage type of the damaged angle steel components of the transmission tower, and locate the position of the damaged angle steel components by combining them with the construction structure diagram of the transmission tower under test in S1. S3. Collect data on the wind force changes experienced by the damaged angle steel components in the actual environment, simulate the corresponding wind force changes using ANSYS finite element software, and calculate the normal wind load on the damaged angle steel components before they were damaged. and conventional load-bearing capacity ; S4. Based on the damage type of the damaged angle steel component of the transmission tower determined in S2, match the corresponding repair and reinforcement method; S5. Simulate the finite element model of the repair after different repair and reinforcement methods using ANSYS finite element software; S6. Calculate the ultimate bearing capacity corresponding to different repair finite element models. and repair wind load ; S7, combined with ultimate bearing capacity and repair wind load Based on the numerical status, select the appropriate repair and reinforcement method.

2. The method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement according to claim 1, characterized in that: The method for simulating the finite element model of the transmission tower under test using ANSYS finite element software in S1 includes the following steps: S1.1 Select the three-dimensional beam element BEAM188 to simulate the main material and cross diagonal members of the transmission tower, obtain the tensile, compressive, torsional and shear force data of the main material and cross diagonal members in the transmission tower, record the deformation of the transmission tower under different conditions into the model system, set the single-sided constraints at different ends of the transmission tower, and ensure that the construction direction of the angle steel material of the transmission tower meets the actual design requirements. S1.2 Select the two-dimensional tension and compression unit LINK180 to simulate the auxiliary materials of the transmission tower, and input the tension and compression data of the auxiliary materials of the transmission tower into the model system; S1.3 Select a node coupling method to simulate the cross-braced connecting bolts set in the transmission tower, so that the linear displacement of the transmission tower support node is the same in different directions; S1.4 Set translational and rotational degrees of freedom in different directions as constraints to simulate the connection between the foundation and support of the transmission tower; S1.5 Apply wind load directly to the support nodes of the transmission tower to simulate the stress changes of the conductors and nodes in the transmission tower. S1.6 Using the constructed transmission tower model, simulate the changes in the foundation displacement of the transmission tower caused by ground deformation and ground movement, and set the constraints for the rotation of the transmission tower.

3. The method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement according to claim 1, characterized in that: The method for determining the damage type of the damaged angle steel component of the transmission tower in S2 includes the following steps: S2.

1. Based on the acquired images of the damaged angle steel components of the transmission tower under test, determine the damaged area of ​​the angle steel components; S2.2 Damage located at the edge of the angle steel component is marked as notch damage. The damage type located on the surface of the angle steel component is marked as crack damage. and crack damage ; S2.

3. Based on the images of the damaged angle steel components, determine whether the damage is due to cracks. and crack damage Damage length and the width of the damage ; S2.4 Define the range of crack damage length , crack damage width range Length range of crack damage and the range of crack damage width Damaged split lines in the region and crack damage .

4. The method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement according to claim 3, characterized in that: The splitting pattern in the middle region of S2.4 is damaged. and crack damage The method includes the following steps: S2.4.1 Calculate the damage length of the current damaged area. and maximum damage width ; S2.4.2 Determine the damage length and maximum damage width Location; when Or the width of the damage Crack damage width range The current damage type is marked as crack damage; When the damage length Crack damage length range And maximum damage width Crack damage width range The current damage type is marked as crack damage.

5. The method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement according to claim 1, characterized in that: The conventional wind load in S3 The calculation uses a wind load calculation algorithm, and the algorithm formula is as follows: ； ； in, The standard value for wind load on transmission towers. The wind pressure height variation coefficient is given at a height of z. This is the basic wind pressure coefficient. Let z be the wind vibration coefficient at height z. This represents the projected area of ​​the angle steel member under wind load. This is a coefficient affected by wind pressure height and wind pressure fluctuations. This is a coefficient influenced by the shape and mode shape of the angle steel structure. This is the pulsation amplification coefficient.

6. The method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement according to claim 5, characterized in that: The calculation of conventional bearing capacity in S3 The method includes the following steps: S3.

1. Using the finite element model, obtain the stress state of angle steel at different heights; S3.2 Simulate different wind speeds and directions to obtain the conventional wind loads on angle steel components of different heights. Maximum compressive stress Maximum tensile stress and maximum displacement Marked as a regular reference value ; S3.

3. Based on the data acquired in S3.2, create a table corresponding to the acquired data and draw a simulation graph; S3.4, Use the acquired data as a regular load-bearing capacity The parameter values ​​are determined, and the corresponding weights are defined based on the rate of change of each acquired data item. The weights are directly proportional to the rate of change.

7. The method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement according to claim 6, characterized in that: The method for selecting a suitable repair and reinforcement method in S7 includes the following steps: S7.1 Obtain various data under different repair and reinforcement methods; S7.2, and compare it with the conventional reference data in S3.2, determine the difference between each acquired data and the corresponding conventional reference data, and mark it as the repair difference. ; S7.3 Establish the repair difference range for various routine reference data Determine the repair difference range within different wind directions. Repair difference Marked as matching rate ; S7.4 Compare the matching rates of various repair and reinforcement methods. The repair and reinforcement method with the highest matching rate will be selected as the appropriate repair and reinforcement method.

8. The method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement according to claim 7, characterized in that: The matching rate in S7.3 The acquisition uses a matching selection algorithm, the formula of which is as follows: ； ； in, These are the actual parameter data values ​​obtained through simulation using repair and reinforcement methods. These are standard reference values. To repair the difference, To repair the difference range, This is the matching function.

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