Method for calculating bearing capacity of power transmission tower angle steel after nondestructive reinforcement

Abstract

The invention relates to the technical field of power transmission tower angle steel bearing capacity calculation, in particular to a method for calculating the bearing capacity of power transmission tower angle steel after nondestructive reinforcement. The method comprises the following steps: calculating ultimate bearing capacities B < ultimate > and repair wind loads W < repair > corresponding to different repair finite element models; and an adaptive repairing and reinforcing method is selected in combination with the numerical value state of the ultimate bearing capacity Bultimate and the repairing wind load Wlrepair. According to the method, the repairing finite element models under different repairing and reinforcing methods are simulated to obtain the corresponding reference values, the reference values are compared with the corresponding conventional reference data, the final matching rate is calculated, the optimal repairing and reinforcing method is matched for different defects, and the simulation effect is improved.

Description

Technical Field

[0001] The invention relates to the technical field of transmission tower angle steel bearing capacity calculation, and in particular to a method for calculating the bearing capacity of a transmission tower angle steel after non-destructive reinforcement. Background Art

[0002] With the continuous development of economy, people's demand for electricity is increasing day by day. In order to meet people's electricity demand, power companies have built a large number of transmission lines. Transmission towers are the arteries of the power system and the basic guarantee for the successful transmission of electric energy. Therefore, how to ensure the safe and stable operation of the power transmission system is crucial. There are many types of transmission towers, mainly divided into ram's horn type, dry-shaped, F-shaped, etc.

[0003] Traditional transmission towers are mostly made of angle steel structures, which are connected and fixed by welding, bolting and clamping. At the same time, the transmission towers are located outdoors and are exposed to wind and sun, so they are easily damaged in exposed locations, such as cracks, fissures or notches in the angle steel. In this case, it is necessary to use flaw detection to assist in determining the damaged and non-damaged areas.

[0004] For cracks or notches, the damage is mainly repaired by welding. Friction-type high-strength bolts and high-strength steel pads can also be arranged to balance the shear force and the friction force distributed along the pads and angle steel surfaces. The appearance after repair is polished to be the same as the original tower material.

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

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

[0007] In order to solve the above problems, a method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement is urgently needed. Summary of the invention

[0008] The purpose of the present 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 raised in the above-mentioned background technology.

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

[0010] S1. According to the construction structure drawing of the transmission tower to be tested, the installation positions of various angle steel components are obtained, and the finite element model of the transmission tower to be tested is simulated by ANSYS finite element software;

[0011] S2, obtaining an image of a damaged angle steel component of the transmission tower to be tested, determining the damage type of the damaged angle steel component of the transmission tower in combination with a damaged image database, and locating the position of the damaged angle steel component in combination with the construction structure diagram of the transmission tower to be tested in S1;

[0012] S3. Collect the wind force change state of the damaged angle steel parts in the actual environment, use ANSYS finite element software to simulate the corresponding wind force change state, and calculate the normal wind load Wl of the damaged angle steel parts before they are damaged. conventional And the conventional bearing capacity Bc conventional ;

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

[0014] S5. Use ANSYS finite element software to simulate the repair finite element model after different repair and reinforcement methods;

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

[0016] S7, combined ultimate bearing capacity Bc ultimate And repair wind load Wl repair Numerical state, select the appropriate repair and reinforcement method.

[0017] As a further improvement of the technical solution, the method of simulating the finite element model of the transmission tower to be tested by ANSYS finite element software in S1 comprises the following steps:

[0018] S1.1. Select the three-dimensional beam unit BEAM188 to simulate the main material and cross diagonal material of the transmission tower, obtain the tension, pressure, torsion and shear force data of the main material and cross diagonal material in the transmission tower, enter the deformation of the transmission tower under different conditions into the model system, set the unilateral constraints at different ends of the transmission tower, and make the construction direction of the angle steel material of the transmission tower meet 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 pressure data of the auxiliary materials of the transmission tower into the model system;

[0020] S1.3. Select the node coupling mode to simulate the cross-diagonal material connection bolts set in the transmission tower, so that the linear displacement of the transmission tower support node in different directions is the same;

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

[0022] S1.5. Apply wind load directly to the supporting nodes of the transmission tower, and simulate the force changes of the conductors and nodes in the transmission tower through the applied wind load;

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

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

[0025] S2.1. Determine the damaged area of ​​the angle steel component based on the acquired image of the damaged angle steel component of the transmission tower to be tested;

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

[0027] S2.3, combined with the damaged angle steel component image, obtain the crack damage C damage And crack damage Cr damage The damaged length Le damage and the damaged width Wi damage ;

[0028] S2.4. Define the crack damage length range C led , Crack damage width range C wid , Crack damage length range Cr led And the crack damage width range Cr wid , distinguish cracks from damaged C damage And crack damage Cr damage .

[0029] As a further improvement of the technical solution, the S2.4 middle zone crack line is damaged C damage And crack damage Cr damage The method comprises the following steps:

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

[0031] S2.4.2. Determine the damage length Le damage and the maximum damage width Wi damage The scope of location;

[0032] When the damage length Le damage ∈Crack damage length range Cr led Or the damaged width Wi damage ∈Crack damage width range Cr wid , mark the current damage type as crack damage;

[0033] When the damage length Le damage ∈Crack damage length range C led And the maximum damage width Wi damage ∈Crack damage width range C wid , marking the current damage type as crack damage.

[0034] As a further improvement of this technical solution, the conventional wind load W1 in S3 conventional The calculation adopts the wind load calculation algorithm, and its algorithm formula is as follows:

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

[0036] β z =1+δε1ε2;

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

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

[0039] S3.1. Combine the finite element model to obtain the stress state of angle steels at different heights;

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

[0041] S3.3, combining the acquired data in S3.2, formulating a table corresponding to the acquired data, and drawing a simulation graph;

[0042] S3.4. Use the acquired data as the normal bearing capacity Bc conventional The parameter value is determined, and the corresponding weight is defined according to the change rate of each item of acquired data, and the weight is proportional to the change rate.

[0043] As a further improvement of the technical solution, the method of selecting an adapted repair and reinforcement method in S7 comprises the following steps:

[0044] S7.1. Obtain various acquisition data under different repair and reinforcement method states;

[0045] S7.2, and compare 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 Reg for each conventional reference data difference , determine the different wind direction ranges that meet the repair difference range Reg difference The repair difference Re difference , marked as matching rate Ma ratio ;

[0047] S7.4. Compare the matching rates of various repair and reinforcement methods Ma ratio , the repair and reinforcement method with the highest matching rate is taken as the adapted repair and reinforcement method.

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

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

[0050]

[0051] Among them, Ac value is the actual parameter data value obtained by simulation of the repair and reinforcement method, Ma rate is a conventional reference value, Re difference To compensate for the difference, Reg difference is the patching difference range, and F(Ma) is the matching function.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] In the method for calculating the bearing capacity of the transmission tower angle steel after non-destructive reinforcement, the repair finite element model under different repair and reinforcement methods is simulated to obtain the corresponding reference values, which are compared with the corresponding conventional reference data, and the final matching rate is calculated to match the best repair and reinforcement methods for different defects and improve the simulation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a flowchart of the overall method of the present invention;

[0055] Figure 2 A method step diagram of simulating a finite element model of a transmission tower to be tested by using ANSYS finite element software according to the present invention;

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

[0057] Figure 4 The present invention distinguishes the cracks and damages C damage And crack damage Cr damage Method steps diagram;

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

[0059] Figure 6 is a conventional reference value table of the present invention;

[0060] Figure 7 This is a method step diagram for selecting an appropriate repair and reinforcement method of the present invention. DETAILED DESCRIPTION

[0061] The following will be combined with the accompanying drawings in the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] See also Figure 1-Figure 7 As shown, a method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement is provided, comprising the following steps:

[0063] S1. According to the construction structure drawing of the transmission tower to be tested, the installation positions of various angle steel components are obtained, and the finite element model of the transmission tower to be tested is simulated by ANSYS finite element software;

[0064] S2, obtaining an image of a damaged angle steel component of the transmission tower to be tested, determining the damage type of the damaged angle steel component of the transmission tower in combination with a damaged image database, and locating the position of the damaged angle steel component in combination with the construction structure diagram of the transmission tower to be tested in S1;

[0065] S3. Collect the wind force change state of the damaged angle steel parts in the actual environment, use ANSYS finite element software to simulate the corresponding wind force change state, and calculate the normal wind load Wl of the damaged angle steel parts before they are damaged. conventional And the conventional bearing capacity Bc conventional ;

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

[0067] S5. Use ANSYS finite element software to simulate the repair finite element model after different repair and reinforcement methods;

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

[0069] S7, combined ultimate bearing capacity Bc ultimate And repair wind load Wl repair Numerical state, select the appropriate repair and reinforcement method.

[0070] When used specifically, the corresponding non-destructive reinforcement method is planned for the transmission tower under different damage states. First, the construction structure of the transmission tower, the shape structure of each angle steel, and the connection method and connection position between the adjacent angle steels need to be determined according to the construction structure diagram of the transmission tower to be tested, and the installation position of each angle steel component is obtained. The finite element model of the transmission tower to be tested is simulated by ANSYS finite element software, and then the image of the damaged angle steel component of the transmission tower to be tested is obtained. For example, the angle steel structure images of different areas of the transmission tower are obtained by patrolling and shooting with a drone, and the damaged image database is combined to determine the damage type of the damaged angle steel component of the transmission tower, that is, image comparison is performed to determine the damage type, which is consistent with steel cracks, fissures or gaps, and then the damaged angle steel component is located in combination with the construction structure diagram of the transmission tower to be tested in S1;

[0071] After completing the positioning of the damaged angle steel component, the wind force change state of the damaged angle steel component in the actual environment was collected, and the corresponding wind force change state was simulated using ANSYS finite element software, and the conventional wind load Wl of the damaged angle steel component before it was damaged was calculated. conventional And the conventional bearing capacity Bc conventional , as a reference value for later comparison;

[0072] Since different damages can be repaired by a variety of non-destructive repair methods, for example, cracks can be repaired by welding or by arranging friction-type high-strength bolts and high-strength steel pads. The two methods have different repair surfaces, and the corresponding bearing capacity and wind load will also be different. In order to select the best non-destructive repair method, it is necessary to match the corresponding repair and reinforcement method by combining the damage type of the damaged angle steel parts of the transmission tower determined in S2, that is, each adapted repair method is adopted, and the repair finite element model after different repair and reinforcement methods is simulated by ANSYS finite element software, and then the corresponding ultimate bearing capacity Bc is calculated by using the same wind force change. ultimate And repair wind load Wl repair , and finally by combining the ultimate bearing capacity Bc ultimate And repair wind load Wl repair Numerical state, select the appropriate repair and reinforcement method.

[0073] In addition, the method for simulating the finite element model of the transmission tower to be tested by using ANSYS finite element software in S1 includes the following steps:

[0074] S1.1. Select the three-dimensional beam unit BEAM188 to simulate the main material and cross diagonal material of the transmission tower, obtain the tension, pressure, torsion and shear force data of the main material and cross diagonal material in the transmission tower, enter the deformation of the transmission tower under different conditions into the model system, set the unilateral constraints at different ends of the transmission tower, and make the construction direction of the angle steel material of the transmission tower meet 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 pressure data of the auxiliary materials of the transmission tower into the model system;

[0076] S1.3. Select the node coupling mode to simulate the cross-diagonal material connection bolts set in the transmission tower, so that the linear displacement of the transmission tower support node in different directions is the same;

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

[0078] S1.5. Apply wind load directly to the supporting nodes of the transmission tower, and simulate the force changes of the conductors and nodes in the transmission tower through the applied wind load;

[0079] S1.6. Use the constructed transmission tower model to simulate the displacement changes of the transmission tower foundation caused by surface deformation and surface 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 comprises the following steps:

[0081] S2.1. Determine the damaged area of ​​the angle steel component based on the acquired image of the damaged angle steel component of the transmission tower to be tested;

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

[0083] S2.3, combined with the damaged angle steel component image, obtain the crack damage C damage And crack damage Cr damage The damaged length Le damage and the damaged width Wi damage ;

[0084] S2.4. Define the crack damage length range C led , Crack damage width range C wid , Crack damage length range Cr led And the crack damage width range Cr wid , distinguish cracks from damaged C damage And crack damage Cr damage .

[0085] In specific use, in the process of determining the damage type of the damaged angle steel component of the transmission tower, since the images of different damage types are different and the locations are also different, it is necessary to first combine the acquired images of the damaged angle steel component of the transmission tower to be tested 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 at the edge of the angle steel component, it is marked as notch damage G. damage When the damaged area is on the surface of the angle steel component, there are two possibilities: the crack damage C damage And crack damage Cr damage In order to distinguish the two damage types, it is necessary to define the crack damage length range C in advance. led , Crack damage width range C wid , Crack damage length range Cr led And the crack damage width range Cr wid , as a distinction between damaged fissures C damage And crack damage Cr damage Reference standard.

[0086] Furthermore, the split lines in the middle of S2.4 are damaged. damage And crack damage Cr damage The method comprises the following steps:

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

[0088] S2.4.2. Determine the damage length Le damage and the maximum damage width Wi damage The scope of location;

[0089] When the damage length Le damage ∈Crack damage length range Cr led Or the damaged width Wi damage ∈Crack damage width range Cr wid , mark the current damage type as crack damage;

[0090] When the damage length Le damage ∈Crack damage length range C led And the maximum damage width Wi damage ∈Crack damage width range C wid , marking the current damage type as crack damage.

[0091] In specific use, since the crack range is generally larger than the crack range, it is necessary to calculate the damage length Le of the current damaged area during the differentiation process. damage and the maximum damage width Wi damage , and the crack damage length range C led Less than the crack damage length range Cr led , crack damage width range C wid Less than the crack damage width range Cr wid , so only when Le damage ∈Cr led or Wi damage ∈Cr wid , the two meet one of the conditions, that is, the current damage type is marked as crack damage, when Le damage ∈C led And Wi damage ∈C wid , both of which meet the requirements, marking the current damage type as crack damage.

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

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

[0094] βz =1+δε1ε2;

[0095] Among them, ω0 is the standard value of wind load on the transmission tower, μ z is the wind pressure height variation coefficient at height z, μ s is the basic wind pressure coefficient, β z is the wind vibration coefficient at height z, S f is the projected area of ​​the angle steel member under the action of wind load, ε1 is the coefficient affected by wind pressure height and wind pressure pulsation, ε2 is the coefficient affected by the shape and vibration mode of the angle steel structure, and δ is the pulsation increase 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 damage being repaired in different ways, the projected area S of the angle steel member under the wind load f The angle steel structure shape and the coefficient ε2 of vibration mode will change. f ε2 is entered into the formula for calculation to obtain the repair wind load Wl corresponding to different repair methods repair , as a reference for later selection of the best non-destructive repair and reinforcement.

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

[0098] S3.1. Combine the finite element model to obtain the stress state of angle steels at different heights;

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

[0100] S3.3, based on the acquired data in S3.2, formulate a table corresponding to the acquired data and draw a simulation graph;

[0101] S3.4. Use the acquired data as the normal bearing capacity Bc conventional The parameter value is determined, and the corresponding weight is defined according to the change rate of each item of acquired data, and the weight is proportional to the change rate.

[0102] Due to the conventional bearing capacity Bc conventional This solution is related to multiple data of angle steel, and combines the conventional wind load Wl conventional , Maximum compressive stress Cs maximum, Maximum tensile stress Ts maximum and the maximum displacement Dis maximum As reference data, the bearing capacity values ​​are the maximum tolerance range of various data under normal conditions. If the values ​​are exceeded, the transmission tower will collapse or collapse. The maximum values ​​of various parameter values ​​also need to be verified after later repairs and reinforcements. Figure 6 As shown, the angle steel selected by the present invention at a height of 30m is used for the experiment. When the wind direction changes from 0 degrees to 60 degrees, the conventional wind load Wl conventional , Maximum compressive stress Cs maximum , and the maximum displacement Dis maximum Both gradually decrease, while the maximum tensile stress Ts maximum Gradually increase, for example, the change rates of various parameter values ​​from 0 to 30 degrees are:

[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] From the above results, it can be seen that the maximum change rate is the maximum compressive stress Cs maximum The rate of change, that is, under the wind force state of 0-30 degrees, the maximum compressive stress Cs needs to be used maximum As a reference value for verifying the bearing capacity of the transmission tower angle steel after non-destructive reinforcement, it is necessary to determine the maximum compressive stress Cs corresponding to different repair and reinforcement methods in the later verification process. maximum and the maximum compressive stress Cs maximum Compare it with 654 / MPa to determine the size of the difference.

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

[0109] Furthermore, the method of selecting an adapted repair and reinforcement method in S7 includes the following steps:

[0110] S7.1. Obtain various acquisition data under different repair and reinforcement method states;

[0111] S7.2, and compare 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 ;

[0112] S7.3. Establish the repair difference range Reg for each conventional reference data difference , determine the different wind direction ranges that meet the repair difference range Reg difference The repair difference Re difference , marked as matching rate Ma ratio ;

[0113] S7.4. Compare the matching rates of various repair and reinforcement methods Ma ratio , the repair and reinforcement method with the highest matching rate is taken as the adapted repair and reinforcement method.

[0114] S7.3 Matching rate Ma ratio The matching selection algorithm is used to obtain , and its algorithm formula is as follows:

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

[0116]

[0117] Among them, Ac value is the actual parameter data value obtained by simulation of the repair and reinforcement method, Ma rate is a conventional reference value, Re difference To compensate for the difference, Reg difference is the patching difference range, and F(Ma) is the matching function.

[0118] In the specific calculation process, the corresponding parameter values ​​are first obtained through the repair finite element model simulated by ANSYS finite element software, and then compared with the corresponding conventional reference data to determine the difference between each acquired data and the corresponding conventional reference data, which is marked as the repair difference Re. difference In order to distinguish the matching effects of different repair and reinforcement methods, it is necessary to establish the repair difference range Reg of various conventional reference data in advance. difference , determine the different wind direction ranges that meet the repair difference range Reg difference The repair difference Re difference , marked as matching rate Ma ratio , the highest matching rate Ma is selected in the later comparison ratio The repair and reinforcement method is used as an adaptive repair and reinforcement method. For example, under the wind force state of 0-30 degrees, it can be known from the above calculation that the corresponding conventional reference value Ma rateis the maximum compressive stress Cs maximum , the conventional value is 654 / MPa. At this time, the maximum compressive stress Cs simulated under different repair and reinforcement methods under the wind force state of 0-30 degrees is obtained. maximum , and the difference is calculated with the conventional value of 654 / MPa. There are three repair and reinforcement methods, A, B and C. The maximum compressive stress Cs corresponding to method A maximum The value is a1, and the maximum compressive stress Cs corresponding to method B maximum The value is b1, the maximum compressive stress Cs corresponding to method B maximum The value is c1, and the repair difference Re of methods A, B and C is difference They are a1-654 / MPa, b1-654 / MPa and c1-654 / MPa respectively, and these repair differences Re are determined difference Is it in the repair difference range Reg difference When the repair difference Re corresponding to method A and B is difference In the repair difference range Reg difference If the repair reinforcement method A and B are within 0-30 degrees, it means that the matching rate Ma ratio 100%. When the wind speed is between 0 and 30 degrees, the repair and reinforcement method A meets the conventional repair requirements. The matching rate Ma ratio Still 100%, the repair reinforcement method B does not meet the requirements, and the matching rate Ma ratio That is 50%, until the repair difference Re of all wind directions is completed difference Determine the work and obtain the final matching rate Ma of different repair and reinforcement methods ratio , the highest matching rate Ma ratio The corresponding repair and reinforcement method is marked as an adapted repair and reinforcement method.

[0119] The above shows and describes 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 by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached 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: The steps include: S1. According to the construction structure drawing of the transmission tower to be tested, the installation positions of various angle steel components are obtained, and the finite element model of the transmission tower to be tested is simulated by ANSYS finite element software; S2, obtaining an image of a damaged angle steel component of the transmission tower to be tested, determining the damage type of the damaged angle steel component of the transmission tower in combination with a damaged image database, and locating the position of the damaged angle steel component in combination with the construction structure diagram of the transmission tower to be tested in S1; S3. Collect the wind force change state of the damaged angle steel parts in the actual environment, use ANSYS finite element software to simulate the corresponding wind force change state, and calculate the normal wind load Wl of the damaged angle steel parts before they are damaged. conventional And the conventional bearing capacity Bc conventional ; S4, matching the corresponding repair and reinforcement method based on the damage type of the damaged angle steel component of the transmission tower determined in S2; S5. Use ANSYS finite element software to simulate the repair finite element model after different repair and reinforcement methods; S6. Calculate the ultimate bearing capacity Bc corresponding to different repaired finite element models ultimate And repair wind load Wl repair ; S7, combined ultimate bearing capacity Bc ultimate And repair wind load Wl repair Numerical state, select the appropriate repair and reinforcement method.

2. The method for calculating the bearing capacity of the transmission tower angle steel after non-destructive reinforcement according to claim 1 is characterized in that: The method of simulating the finite element model of the transmission tower to be tested by ANSYS finite element software in S1 comprises the following steps: S1.

1. Select the three-dimensional beam unit BEAM188 to simulate the main material and cross diagonal material of the transmission tower, obtain the tension, pressure, torsion and shear force data of the main material and cross diagonal material in the transmission tower, enter the deformation of the transmission tower under different conditions into the model system, set the unilateral constraints at different ends of the transmission tower, and make the construction direction of the angle steel material of the transmission tower meet 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 pressure data of the auxiliary materials of the transmission tower into the model system; S1.

3. Select the node coupling mode to simulate the cross-diagonal material connection bolts set in the transmission tower, so that the linear displacement of the transmission tower support node in different directions is the same; S1.

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

5. Apply wind load directly to the supporting nodes of the transmission tower, and simulate the force changes of the conductors and nodes in the transmission tower through the applied wind load; S1.

6. Use the constructed transmission tower model to simulate the displacement changes of the transmission tower foundation caused by surface deformation and surface movement, and set the constraints for the rotation of the transmission tower.

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

1. Determine the damaged area of ​​the angle steel component based on the acquired image of the damaged angle steel component of the transmission tower to be tested; S2.

2. The damage type at the edge of the angle steel component is marked as notch damage G damage , the damage type on the surface of the angle steel component is marked as crack damage C damage And crack damage Cr damage ; S2.3, combined with the damaged angle steel component image, obtain the crack damage C damage And crack damage Cr damage The damaged length Le damage and the damaged width Wi damage ; S2.

4. Define the crack damage length range C led , Crack damage width range C wid , Crack damage length range Cr led And the crack damage width range Cr wid , distinguish cracks from damaged C damage And crack damage Cr damage .

4. The method for calculating the bearing capacity of the transmission tower angle steel after non-destructive reinforcement according to claim 3 is characterized in that: The S2.4 mid-region split striae were damaged C damage And crack damage Cr damage The method comprises the following steps: S2.4.

1. Calculate the damage length Le of the current damaged area damage and the maximum damage width Wi damage ; S2.4.

2. Determine the damage length Le damage and the maximum damage width Wi damage The scope of location; When the damage length Le damage ∈Crack damage length range Cr led Or the damaged width Wi damage ∈Crack damage width range Cr wid , mark the current damage type as crack damage; When the damage length Le damage ∈Crack damage length range C led And the maximum damage width Wi damage ∈Crack damage width range C wid , marking the current damage type as crack damage.

5. The method for calculating the bearing capacity of the transmission tower angle steel after non-destructive reinforcement according to claim 1 is characterized in that: The conventional wind load W1 in S3 conventional The calculation adopts the wind load calculation algorithm, and its algorithm formula is as follows: Wl conventional =ω0·μ z ·m s ·b z ·S f ; b z =1+δε1ε2; Among them, ω0 is the standard value of wind load on the transmission tower, μ z is the wind pressure height variation coefficient at height z, μ s is the basic wind pressure coefficient, β z is the wind vibration coefficient at height z, S f is the projected area of ​​the angle steel member under the action of wind load, ε1 is the coefficient affected by wind pressure height and wind pressure pulsation, ε2 is the coefficient affected by the shape and vibration mode of the angle steel structure, and δ is the pulsation increase coefficient.

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

1. Combine the finite element model to obtain the stress state of angle steels at different heights; S3.

2. Simulate different wind speeds and wind directions to obtain the conventional wind load Wl of angle steel components at different heights conventional , Maximum compressive stress Cs maximum , Maximum tensile stress Ts maximum and the maximum displacement Dis maximum , marked as the normal reference value Ma rate ; S3.3, combining the acquired data in S3.2, formulating a table corresponding to the acquired data, and drawing a simulation graph; S3.

4. Use the acquired data as the normal bearing capacity Bc conventional The parameter value is determined, and the corresponding weight is defined according to the change rate of each item of acquired data, and the weight is proportional to the change rate.

7. The method for calculating the bearing capacity of transmission tower angle steel after non-destructive reinforcement according to claim 1 is characterized in that: The method of selecting an adapted repair and reinforcement method in S7 comprises the following steps: S7.

1. Obtain various acquisition data under different repair and reinforcement method states; S7.2, and compare 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 ; S7.

3. Establish the repair difference range Reg for each conventional reference data difference , determine the different wind direction ranges that meet the repair difference range Reg difference The repair difference Re difference , marked as matching rate Ma ratio ; S7.

4. Compare the matching rates of various repair and reinforcement methods Ma ratio , the repair and reinforcement method with the highest matching rate is taken as the adapted repair and reinforcement method.

8. The method for calculating the bearing capacity of the transmission tower angle steel after non-destructive reinforcement according to claim 7 is characterized in that: The matching rate Ma in S7.3 ratio The matching selection algorithm is used to obtain , and its algorithm formula is as follows: And value -Ma rate |=Re difference ; Among them, Ac value is the actual parameter data value obtained by simulation of the repair and reinforcement method, Ma rate is a conventional reference value, Re difference To compensate for the difference, Reg difference is the patching difference range, and F(Ma) is the matching function.

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