Bolt loosening prevention alarm system for tower crane

Abstract

The invention belongs to the technical field of tower crane bolt looseness early warning and recognition, and particularly discloses a tower crane bolt looseness prevention alarm system which comprises the steps that by recognizing the gravity center position of an object on a tower crane boom, the bolt looseness situation is recognized according to the difference of the gravity center position of the object, and the tower crane bolt looseness prevention alarm system is obtained; the potential safety hazard of bolt looseness can be found more accurately; by analyzing the corresponding displacement stability response of the carrying movement track of the tower crane boom and the torque looseness degree of each connecting bolt corresponding to each standard knot, the looseness possibility of the bolts is checked from the carrying dimension of the boom; a plurality of factors such as a wind direction stress resonance layer, a vibration abnormal sound layer and a corrosion mottle layer are comprehensively considered, and the loosening possibility of the bolt is inspected from the wind load characteristic dimension; the corresponding positions of the loosened bolts are positioned by constructing the loosening tendency relational expression of the corresponding connecting bolts of the standard knots of the tower crane, and a more accurate and effective maintenance plan can be made according to real-time data and analysis results.

Description

Technical Field

[0001] The invention belongs to the technical field of early warning identification of loosening of tower crane bolts and relates to an alarm system for preventing tower crane bolts from loosening. Background Art

[0002] With the vigorous development of the construction industry and the expansion of industrial production, the work tasks of tower cranes are becoming increasingly arduous, and their operating safety is directly related to the life safety of construction site personnel and the smooth progress of the project. Tower cranes usually work in complex outdoor environments and face various harsh natural conditions and working conditions. For example, strong winds will cause tower cranes to bear greater lateral forces and torques, increase the stress burden on bolts, and easily cause bolt loosening; in addition, tower cranes will generate various dynamic loads and vibrations during frequent lifting, rotation, and amplitude changes, which will also accelerate the loosening and wear of bolts. In this complex and harsh operating environment, traditional detection methods and technologies are difficult to effectively cope with, so there is an urgent need for a more intelligent, sensitive and reliable bolt loosening monitoring and alarm system that can adapt to complex working conditions and accurately monitor the loosening of bolts in real time, providing strong protection for the safe operation of tower cranes.

[0003] Although there are some existing solutions for early warning and identification of tower crane bolt loosening, there are still the following limitations: when the existing technology identifies bolt loosening, it usually simply issues an alarm. When formulating maintenance plans, it can usually only perform static torque detection based on regular detection data, and cannot grasp the torque changes of the bolts during the operation of the tower crane in real time. At the same time, in the existing technology, the detection and analysis of the resonance between the torque of the connecting bolts and the wind direction is not perfect, which makes it easy for the tower crane connection bolts to loosen and be damaged due to resonance when encountering severe weather conditions such as strong winds, seriously affecting the safe operation of the tower crane. Summary of the invention

[0004] In view of this, in order to solve the problems raised in the above background technology, a tower crane anti-bolt loosening alarm system is now proposed.

[0005] The purpose of the present invention can be achieved by the following technical solutions: The present invention provides a tower crane anti-bolt loosening alarm system, the system comprising: a tower crane bolt load analysis module for obtaining the carrying movement trajectory of the tower crane boom and its load weight, analyzing the foundation load fluctuation coefficient ε of each standard section corresponding to each connecting bolt position dot→k The standard sections of the tower crane are numbered 1, 2, ...dot..., c, and the positions of the connecting bolts are numbered 1, 2, ...k..., m.

[0006] The self-vibration detection module is used to extract the number of start-up operations of the tower crane arm in the specified stage of the operation cycle, number the start-up operations as 1, 2, ...i..., b, and analyze the characteristics of the self-vibration results, including the corresponding displacement stability response R of the tower crane arm's carrying movement trajectory trans , the torque looseness of each connecting bolt corresponding to each standard section.

[0007] The external vibration detection module is used to detect the wind load characteristics, including the wind direction and wind force of each start-up operation of the tower crane arm during the specified stage of the operation cycle. From the aspects of wind direction force resonance, vibration abnormal sound, and rust and mottled, the wind load influence coefficient WL of each connecting bolt corresponding to each standard section is evaluated. dot→k .

[0008] The tower crane bolt early warning module is used to combine its own vibration result characteristics and wind load influence coefficient to construct the loosening tendency relationship between the corresponding connecting bolts of each standard section of the tower crane, locate the corresponding position of the loose bolts, and conduct early warning assessment.

[0009] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention can more accurately detect the potential safety hazards of bolt loosening by identifying the center of gravity position of the load on the tower crane boom and identifying the looseness of bolts based on the difference in the center of gravity position of the load.

[0010] (2) The present invention analyzes the displacement stability response of the carrying movement trajectory of the tower crane arm by checking the rotation speed of each standard section during the starting operation, and analyzes the torque looseness by checking the synthetic torque force of each connecting bolt of each standard section during the starting operation, and then checks the possibility of bolt loosening from the load dimension of the boom, closely combining the operating state of the tower crane with the mechanical properties of the bolts, forming a comprehensive safety guarantee system.

[0011] (3) The present invention examines the possibility of bolt loosening from the dimension of wind load characteristics by examining the stress resonance between the synthetic torque force of the connecting bolts and the wind direction, the vibration and abnormal sound of the connecting bolts when they are stressed, the degree of rust and mottled spots of the connecting bolts, and the stress concentration of crack sources in the vicinity thereof, which helps to make targeted adjustments and improvements to the wind protection measures of the tower crane based on the inspection results.

[0012] (4) The present invention constructs a loosening tendency relationship formula for each connecting bolt corresponding to each standard section of the tower crane by analyzing the foundation bearing fluctuation coefficient of each connecting bolt position corresponding to each standard section, and combining the characteristics of its own vibration results and the wind load influence coefficient. The corresponding position of the loose bolt is located based on this, which helps to formulate a more accurate and effective maintenance plan based on real-time data and analysis results. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0014] Figure 1 It is a schematic diagram of the connection of the system modules of the present invention.

[0015] Figure 2 It is a schematic diagram of a standard section of a tower crane according to the present invention.

[0016] Figure numerals: 1. Standard section. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of 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.

[0018] See also Figure 1 As shown, the present invention provides a tower crane bolt loosening prevention alarm system, which includes: a tower crane bolt load analysis module, an own vibration detection module, an external vibration detection module, and a tower crane bolt early warning module.

[0019] The tower crane bolt load analysis module is connected to the self-vibration detection module, the self-vibration detection module is connected to the external vibration detection module, and the tower crane bolt early warning module is respectively connected to the tower crane bolt load analysis module, the self-vibration detection module, and the external vibration detection module.

[0020] See also Figure 2 As shown, the tower crane bolt load analysis module is used to obtain the carrying movement trajectory of the tower crane boom and its load weight, and analyze the foundation load fluctuation coefficient ε of each connection bolt position corresponding to each standard section dot→k The standard sections of the tower crane are numbered 1, 2, ...dot..., c, and the positions of the connecting bolts are numbered 1, 2, ...k..., m.

[0021] In a preferred embodiment, the analysis of the foundation load fluctuation coefficient of each connection bolt position corresponding to each standard section includes: locating the rotation angle θ of each connection bolt position corresponding to each standard section position when the tower crane arm moves to each standard section position from the carrying movement trajectory of the tower crane arm dot→k .

[0022] The slewing angle refers to the horizontal rotation angle of the horizontal axial position of the tower crane arm when it moves to each standard section position relative to the initial horizontal axial position.

[0023] Identify the center of gravity of the load on the tower crane arm, and then obtain its distance relative to the corresponding connection bolt positions of each standard section, which is recorded as the external weight distance l of the corresponding connection bolt positions of each standard section. dot→k .

[0024] Analyze the foundation bearing fluctuation coefficient of each standard section corresponding to each connecting bolt position Where θ0 and l0 represent the preset reference rotation angle and reference external weight distance respectively.

[0025] In a further preferred embodiment, the corresponding method for identifying the center of gravity position of the load on the tower crane arm is: use a high-precision scanner to perform a three-dimensional scan of the load on the tower crane arm, obtain the contour data of the load, generate a three-dimensional model of the load, and then use three-dimensional modeling and computing software (such as CAD, CAE, etc.) to load and analyze the three-dimensional model of the load to derive the center of gravity position.

[0026] The present invention can more accurately find potential safety hazards of loose bolts by identifying the center of gravity position of the load on the tower crane lifting arm and identifying the loose bolts according to the difference in the center of gravity position of the load. In actual operation, tower cranes often need to carry objects of different weights and shapes, and the center of gravity position and the carrying movement trajectory of these objects will directly affect the stress conditions of each standard section and connecting bolt of the tower crane. Therefore, by identifying the loose bolts according to the difference in the center of gravity position of the load, the potential safety hazards of loose bolts can be more accurately found, so as to take necessary measures for prevention and repair, and avoid serious safety accidents.

[0027] The self-vibration detection module is used to extract the number of start-up operations of the tower crane arm in the specified stage operation cycle, number the start-up operations as 1, 2, ...i..., b, and analyze the characteristics of the self-vibration results, including the corresponding displacement stability response R of the tower crane arm's carrying movement trajectory trans , the torque looseness of each connecting bolt corresponding to each standard section.

[0028] In a preferred embodiment, the analysis of the displacement stability response of the carrying movement trajectory of the tower crane arm includes: obtaining the time t when the tower crane arm moves to each standard section position dot , compare them to calculate the rotation speed of each standard section where t (dot-1)It represents the time for the tower crane arm to move to the dot-1th standard section position, m is the number of bolt positions, and the number of start-up operations of the tower crane arm in the specified stage operation cycle is extracted. Then, the rotation speed of each standard section in each start-up operation is calculated in the same way.

[0029] The starting operation is the cyclic loading operation of the tower crane boom.

[0030] Analyze the displacement stability response of the tower crane arm's carrying movement trajectory in It represents the rotation speed of the dot+1th standard section during the i-th start-up process, Δv represents the corresponding reference deviation value of the preset rotation speed, c represents the number of tower crane standard sections, and b represents the total number of start-up operations.

[0031] In a further preferred embodiment, the torque looseness of each connecting bolt corresponding to each standard section is obtained by arbitrarily constructing a three-dimensional space coordinate system with the tower crane burial point as the coordinate reference point, detecting the strain force conditions through strain gauges arranged at the positions of each connecting bolt corresponding to each standard section, and obtaining the horizontal shear force and vertical tension of each connecting bolt corresponding to each standard section in each starting operation of the tower crane boom within a specified stage operation cycle, multiplying it with the preset unit torque corresponding coordinate distance length, to obtain the horizontal moment and vertical moment of each connecting bolt corresponding to each standard section in each starting operation, and importing them into the three-dimensional space coordinate system according to their coordinate distance length.

[0032] Exemplarily, the three-dimensional space coordinate system is constructed as follows: the main working direction of the tower crane or the main layout direction of the site is the X-axis direction, the direction perpendicular to the X-axis in the horizontal plane is the Y-axis direction, and the vertical upward direction is the Z-axis direction, that is, the lifting direction of the tower crane boom.

[0033] The horizontal moment and vertical moment of each connecting bolt corresponding to each standard section in each starting operation are constructed into a synthetic torque force through the vector synthesis method.

[0034] The synthetic torque force of each connecting bolt corresponding to each standard section in each starting operation is compared, and the torque force movement trajectory of each connecting bolt corresponding to each standard section is constructed. Based on this, the torque dynamics of each connecting bolt corresponding to each standard section of the tower crane are identified. The torque dynamics include rotational torque, axial torque, and shear torque. Then, they are matched with the preset torque looseness corresponding to each torque dynamic to obtain the torque looseness of each connecting bolt corresponding to each standard section.

[0035] The rotational torque refers to the torque movement trajectory gradually forming a closed curve in the three-dimensional space coordinate system. During frequent starting operations, the rotational torque will continuously change the stress state of the bolt, causing the bolt to loosen.

[0036] The axial torque refers to the fact that the torque movement trajectory tends to move more vertically in the three-dimensional space coordinate system, which will cause the bolts to be stretched or compressed. During the operation of the tower crane, the axial torque will cause the bolts to loosen due to the lifting and lowering of the tower crane's boom and the tilting of the tower body.

[0037] The shear torque refers to the fact that the torque movement trajectory tends to move more horizontally in the three-dimensional space coordinate system. During tower crane operation, due to the action of various complex loads, the shear torque can cause the bolts to loosen or even break.

[0038] The present invention can comprehensively and meticulously understand the dynamic characteristics of the tower crane in the actual operation process by checking the rotation speed of each standard section in the starting operation and analyzing the corresponding displacement stability response of the carrying movement trajectory of the tower crane boom. The present invention can also check the synthetic torque force of each connecting bolt corresponding to each standard section in the starting operation and analyze the torque looseness, thereby providing a direct and accurate basis for evaluating the tightening state of the bolts. Furthermore, the loosening possibility of the bolts is checked from the dimension of the boom load, and the operating state of the tower crane is closely combined with the mechanical properties of the bolts to form a comprehensive safety guarantee system.

[0039] The external vibration detection module is used to detect the wind load characteristics, including the wind direction and wind force of each start-up operation of the tower crane arm in the specified stage operation cycle, and evaluate the wind load influence coefficient WL of each connecting bolt corresponding to each standard section from the aspects of wind direction force resonance, vibration abnormal sound, and rust and mottled. dot→k .

[0040] In a preferred embodiment, the wind direction force resonance level detection content includes: detecting the wind direction and wind force of each starting operation of the tower crane boom within a specified stage operation cycle through a wind sensor, and importing the wind direction of each starting operation into a three-dimensional space coordinate system.

[0041] The wind direction angle is specifically: taking the true north direction as a reference (0°), recording the angle of the wind direction relative to the true north direction.

[0042] In the three-dimensional space coordinate system, the wind direction of each start-up operation is compared with the corresponding coordinate direction of the synthetic torque force of each connecting bolt of each standard section in the corresponding start-up operation to obtain the wind direction force resonance angle of each connecting bolt of each standard section in each start-up operation. Compare it with the preset reference resonance angle ρ0, and calculate the wind direction force resonance degree of each connecting bolt corresponding to each standard section of the tower crane

[0043] Specifically, the resonance phenomenon refers to the intensified structural vibration of the bolts connecting the standard section when the pulsation frequency of the wind is close to the natural frequency of the tower crane structure. In the tower crane and bolt system, when the component of the wind direction's excitation effect on the bolt in the force direction is small, the possibility and degree of resonance will be reduced, so the possibility of bolt loosening will also be reduced. For example, assuming that the wind direction is perpendicular to the force direction of the bolt, the projection of the wind direction in the force direction of the bolt is zero. At this time, if there are no other factors that cause frequency matching, resonance will basically not occur.

[0044] In a further preferred embodiment, the vibration abnormal sound level detection content is: monitoring the abnormal sound characteristics of each connecting bolt corresponding to each standard section of the tower crane boom during each start-up operation in a specified stage operation cycle through a strain gauge, comparing it with the preset reference abnormal sound characteristics, and then solving the mean to obtain the vibration abnormal sound risk factor η of each connecting bolt corresponding to each standard section of the tower crane dot→k .

[0045] The rust and mottled layer detection content includes: acquiring images of the areas near the connecting bolts corresponding to each standard section through images, detecting the crack sources in the areas near the connecting bolts corresponding to each standard section based on image recognition technology, and detecting the surface rust characteristics of the connecting bolts corresponding to each standard section of the tower crane, and comparing them with the preset reference rust characteristics to obtain the rust and mottled degree of each connecting bolt corresponding to each standard section of the tower crane.

[0046] Specifically, when the bolt surface is corroded, the rust will continue to corrode the bolt material, destroying its original metal structure. The rust is loose and has low strength, and cannot provide sufficient support for the bolt. Therefore, as the rust continues to worsen, the effective bearing area of ​​the bolt gradually decreases, and the overall strength drops significantly. When the bolt is subjected to external loads, its bearing capacity is weakened and it is easy to deform, which leads to loose connections.

[0047] By collecting the heat source map corresponding to the crack source in the area near each connecting bolt corresponding to each standard section, the corresponding temperature indication of the crack source position is extracted from the heat source map, and it is compared with the preset reference temperature indication to obtain the crack source stress concentration of each connecting bolt corresponding to each standard section.

[0048] The rust and mottled degree of each connecting bolt corresponding to each standard section of the tower crane is multiplied by the stress concentration of the crack source to obtain the mottled loosening risk factor μ of each connecting bolt corresponding to each standard section. dot→k .

[0049] In a further preferred embodiment, the evaluation of the wind load influence coefficient of each connecting bolt corresponding to each standard section includes: recording the wind force of each start-up operation of the tower crane boom in a specified stage operation cycle as w i, and obtain the wind force w0 of the tower crane arm at the current detection moment.

[0050] Evaluate the wind load influence coefficient of each connection bolt corresponding to each standard section

[0051] The present invention can more comprehensively evaluate the wind load influence coefficient of each connecting bolt corresponding to each standard section by comprehensively considering multiple factors such as wind direction force resonance, vibration and noise, and rust and mottle levels, that is, inspecting the force resonance of the synthetic torque force of the connecting bolt and the wind direction, the vibration and noise when the connecting bolt is stressed, the degree of rust and mottle of the connecting bolt and the stress concentration of the crack source in the vicinity thereof, and inspecting the possibility of bolt loosening from the dimension of wind load characteristics. This helps to make targeted adjustments and improvements to the wind protection measures of the tower crane according to the inspection results, such as adding windproof cables, adjusting the angle of the boom, etc., to further enhance the adaptability and safety of the tower crane in severe wind environments, ensure that the tower crane can operate reliably under various meteorological conditions, and provide a strong guarantee for the smooth progress of engineering projects.

[0052] The tower crane bolt early warning module is used to combine its own vibration result characteristics and wind load influence coefficient, construct a loosening tendency relationship between each connecting bolt of each standard section of the tower crane, locate the corresponding position of the loose bolt, and conduct early warning assessment on it.

[0053] In a preferred embodiment, the loosening tendency relationship formula of each connecting bolt corresponding to each standard section of the tower crane is constructed as follows: the load weight G of each start-up operation of the tower crane boom in a specified stage operation cycle is obtained. i , and obtain the load weight G0 of the tower crane arm at the current detection moment.

[0054] The torque looseness of each connecting bolt corresponding to each standard section is recorded as J dot→k , obtain the relationship between the vibration influence of each connecting bolt corresponding to each standard section R0 represents the reference value corresponding to the set displacement stability response.

[0055] Combined with its own vibration result characteristics (R trans ,J dot→k ) and wind load influence coefficient, and construct the loosening tendency relationship between the corresponding connecting bolts of each standard section of the tower crane in They respectively represent the preset self-vibration result characteristics and the corresponding loosening tendency influence weights of the wind load influence coefficient.

[0056] In a further preferred embodiment, the corresponding positions of the loose bolts are located as follows: a loose tendency relationship value is obtained through a loose tendency relationship formula of each connecting bolt corresponding to each standard section of the tower crane, and the loose tendency relationship value is compared with a set safety value of the bolt loosening tendency, and the connecting bolts whose corresponding loose tendency relationship values ​​of each standard section exceed the set safety value are identified and recorded as the corresponding loose bolts of each standard section, and early warning feedback is given for their positions.

[0057] The present invention constructs a loosening tendency relational formula of each connecting bolt corresponding to each standard section of the tower crane by analyzing the foundation bearing fluctuation coefficient of each connecting bolt position corresponding to each standard section, and combines the characteristics of its own vibration results and the wind load influence coefficient, thereby locating the corresponding position of the loose bolt, which helps to formulate a more accurate and effective maintenance plan based on real-time data and analysis results. In addition, when checking the looseness of the bolts, the working conditions of different load weights are taken into consideration. By analyzing the stress conditions of each standard section and connecting bolt of the tower crane under different load conditions, the structural characteristics and performance of the tower crane can be more deeply understood, thereby providing a scientific basis for designing and manufacturing safer, more reliable and more efficient tower cranes.

[0058] The above contents are merely examples and explanations of the concept of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the present invention, they shall all fall within the protection scope of the present invention.

Claims

1. A tower crane bolt loosening alarm system, characterized in that: The system includes: The tower crane bolt load analysis module is used to obtain the moving trajectory of the tower crane arm and its load weight, and analyze the foundation load fluctuation coefficient ε of each connection bolt position corresponding to each standard section dot→k And number each standard section of the tower crane as 1,2,...dot...,c, and number each connecting bolt position as 1,2,...k...,m; The self-vibration detection module is used to extract the number of start-up operations of the tower crane arm in the specified stage of the operation cycle, number the start-up operations as 1, 2, ...i..., b, and analyze the characteristics of the self-vibration results, including the corresponding displacement stability response R of the tower crane arm's carrying movement trajectory trans , the torque looseness of each connecting bolt corresponding to each standard section; The external vibration detection module is used to detect the characteristics of wind loads, and evaluate the wind load influence coefficient WL of each connecting bolt of each standard section from the aspects of wind direction force resonance, vibration noise, and rust and mottled. dot→k ; The tower crane bolt early warning module is used to combine its own vibration result characteristics and wind load influence coefficient to construct the loosening tendency relationship between the corresponding connecting bolts of each standard section of the tower crane, locate the corresponding position of the loose bolts, and conduct early warning assessment.

2. A tower crane bolt loosening prevention alarm system according to claim 1, characterized in that: The analysis of the foundation bearing fluctuation coefficient of each connection bolt position corresponding to each standard section includes: From the carrying movement trajectory of the tower crane boom, the rotation angle θ of each corresponding connecting bolt position when the tower crane boom moves to each standard section position is located. dot→k ; Identify the center of gravity of the load on the tower crane arm, and then obtain its distance relative to the corresponding connection bolt positions of each standard section, which is recorded as the external weight distance l of the corresponding connection bolt positions of each standard section. dot→k ; Analyze the foundation bearing fluctuation coefficient of each standard section corresponding to each connection bolt position Where θ0 and l0 represent the preset reference rotation angle and reference external weight distance respectively.

3. A tower crane bolt loosening prevention alarm system according to claim 2, characterized in that: The corresponding method for identifying the center of gravity position of the load on the tower crane arm is: use a high-precision scanner to perform a three-dimensional scan of the load on the tower crane arm, obtain the contour data of the load, generate a three-dimensional model of the load, and then use three-dimensional modeling and calculation software to load and analyze the three-dimensional model of the load to derive the center of gravity position.

4. The tower crane bolt loosening prevention alarm system according to claim 1 is characterized in that: The analysis of the corresponding displacement stability response of the carrying movement trajectory of the tower crane arm includes: obtaining the time for the tower crane arm to move to each standard section position, comparing them with each other to calculate the rotation speed of each standard section, extracting the number of start-up operations of the tower crane arm in a specified stage operation cycle, and then calculating the rotation speed of each standard section in each start-up operation in a similar manner. Analyze the displacement stability response of the tower crane arm's carrying movement trajectory in It represents the rotation speed of the dot+1th standard section during the i-th start-up process, Δv represents the corresponding reference deviation value of the preset rotation speed, c represents the number of standard sections of the tower crane, and b represents the total number of start-up operations.

5. The tower crane bolt loosening prevention alarm system according to claim 1 is characterized in that: The torque looseness of each connecting bolt corresponding to each standard section is obtained as follows: Taking the tower crane burying point as the coordinate reference point, arbitrarily construct a three-dimensional space coordinate system, obtain the horizontal shear force and vertical tension of each connecting bolt corresponding to each standard section in each start-up operation of the tower crane arm within the specified stage operation cycle, multiply it with the preset unit moment corresponding to the coordinate distance length, obtain the horizontal moment and vertical moment of each connecting bolt corresponding to each standard section in each start-up operation, and import them into the three-dimensional space coordinate system according to their coordinate distance length; The horizontal moment and vertical moment of each connecting bolt of each standard section in each starting operation are constructed into a synthetic torque force by using a vector synthesis method; The synthetic torque force of each connecting bolt corresponding to each standard section in each starting operation is compared, and the torque force movement trajectory of each connecting bolt corresponding to each standard section is constructed. Based on this, the torque dynamics of each connecting bolt corresponding to each standard section of the tower crane are identified. The torque dynamics include rotational torque, axial torque, and shear torque. Then, they are matched with the preset torque looseness corresponding to each torque dynamic to obtain the torque looseness of each connecting bolt corresponding to each standard section.

6. A tower crane bolt loosening prevention alarm system according to claim 5, characterized in that: The wind direction force resonance level detection content includes: The wind direction and wind force of each start-up operation of the tower crane arm in a specified stage operation cycle are detected by a wind sensor, and the wind direction of each start-up operation is imported into a three-dimensional space coordinate system; In the three-dimensional space coordinate system, the wind direction of each start-up operation is compared with the corresponding coordinate direction of the synthetic torque force of each connecting bolt of each standard section in the corresponding start-up operation, and the wind direction force resonance angle of each connecting bolt of each standard section in each start-up operation is obtained. It is compared with the preset reference resonance angle to calculate the wind direction force resonance degree R of each connecting bolt of each standard section of the tower crane. dot→k .

7. A tower crane bolt loosening prevention alarm system according to claim 6, characterized in that: The vibration and noise detection content is: monitoring the noise characteristics of each connecting bolt corresponding to each standard section of the tower crane arm during each start-up operation in a specified stage operation cycle through strain gauges, and solving the vibration and noise risk factor η of each connecting bolt corresponding to each standard section of the tower crane dot→k ; The rust mottled level detection content includes: collecting images of the area near each connecting bolt corresponding to each standard section through images, detecting the crack source in the area near each connecting bolt corresponding to each standard section based on image recognition technology, and detecting the surface rust characteristics of each connecting bolt corresponding to each standard section of the tower crane, comparing it with the preset reference rust characteristics, and obtaining the rust mottled degree of each connecting bolt corresponding to each standard section of the tower crane; By collecting the heat source map corresponding to the crack source in the vicinity of each connecting bolt corresponding to each standard section, the corresponding temperature indication of the crack source position is extracted from the heat source map, and it is compared with the preset reference temperature indication to obtain the stress concentration of the crack source of each connecting bolt corresponding to each standard section; The rust and mottled degree of each connecting bolt corresponding to each standard section of the tower crane is multiplied by the stress concentration of the crack source to obtain the mottled loosening risk factor μ of each connecting bolt corresponding to each standard section. dot→k .

8. The tower crane bolt loosening prevention alarm system according to claim 7 is characterized in that: The wind load influence coefficient of each connecting bolt corresponding to each standard section is evaluated, including: The wind force of each start-up operation of the tower crane arm in the specified stage of the operation cycle is recorded as w i , and obtain the wind force w0 of the tower crane arm at the current detection moment; Evaluate the wind load influence coefficient of each connection bolt corresponding to each standard section 9. The tower crane bolt loosening prevention alarm system according to claim 1 is characterized in that: The loosening tendency relationship formula of each connecting bolt corresponding to each standard section of the tower crane is as follows: Obtain the load weight G of each start-up operation of the tower crane boom in the specified stage operation cycle i , and obtain the load weight G0 of the tower crane arm at the current detection moment; The torque looseness of each connecting bolt corresponding to each standard section is recorded as J dot→k , obtain the relationship between the vibration influence of each connecting bolt corresponding to each standard section R0 represents the reference value corresponding to the set displacement stability response; Combined with its own vibration result characteristics (R trans ,J dot→k ) and wind load influence coefficient, and construct the loosening tendency relationship between the corresponding connecting bolts of each standard section of the tower crane in They respectively represent the preset self-vibration result characteristics and the corresponding loosening tendency influence weights of the wind load influence coefficient.

10. A tower crane bolt loosening prevention alarm system according to claim 9, characterized in that: The method for locating the corresponding positions of the loose bolts is as follows: a loose tendency relationship value is obtained through a loose tendency relationship formula of each connecting bolt corresponding to each standard section of the tower crane, and the loose tendency relationship value is compared with a set safety value of the bolt loosening tendency, and the connecting bolts whose corresponding loose tendency relationship values ​​of each standard section exceed the set safety value are identified and recorded as the corresponding loose bolts of each standard section, and early warning feedback is given to their positions.

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