CN108535355A - Steel section member damage overall-process monitors system and monitoring method - Google Patents

Abstract

The invention discloses a whole-process monitoring system for section steel member damage, which includes a mobile control platform, a magnetic sensor probe and a control system. The mobile control platform is used to be arranged on the steel member. The magnetic sensing probe is arranged on the mobile control platform, and the mobile control platform drives the movement of the magnetic sensing probe to obtain the three-dimensional magnetic induction intensity of the steel member. The control system communicates with the mobile control platform and the magnetic sensor probe to control the work of the mobile control platform and the magnetic sensor probe, and calculates the development of the steel member with time and load according to the information fed back by the mobile control platform and the magnetic sensor probe. Damage location and damage size. The invention also discloses a method for monitoring the damage of the steel structure in the whole process, which solves the problem of damage monitoring and early warning of the steel structure in complex and harsh service environments. It does not need to remove paint and surface sheaths, does not affect the use of the steel structure, and is simple to operate. Moreover, the whole process of damage can be monitored, and the damage location and damage size can be monitored at the same time.

Description

Monitoring system and monitoring method for the whole process of section steel component damage

technical field

The invention relates to the technical field of damage monitoring, in particular to a damage monitoring system and a monitoring method for the whole process of steel member damage.

Background technique

The damage of traditional steel components mainly depends on manual monitoring. During monitoring, it is necessary to remove the steel structure paint, sheath and other protective layers, and mainly observe the external damage degree of the steel structure. This method has low work efficiency and poor accuracy, and requires a lot of manpower. Under the action of wind and rain, high-altitude operations pose a great threat to the safety of surveyors.

In the past two decades, the damage monitoring methods of steel components mainly include resistance strain gauge method, magnetic flux leakage monitoring method, ultrasonic wave, magnetic memory technology, acoustic emission technology, piezoelectric material-polyvinylidene fluoride sensing technology (Polyvinylidene Fluoride, PVDF) , fiber grating sensing technology, infrared thermal imaging, etc. Among them, the resistance strain gauge is a point-type monitoring method, which requires a large number of resistance strain gauges, which is extremely susceptible to environmental electromagnetic interference, and cannot monitor large deformation damage in the later stage. The magnetic flux leakage monitoring method requires special magnetization equipment to apply an external magnetic field, and the operation is very cumbersome and the monitoring accuracy is low. Because there are original defects on the surface of steel components, the ultrasonic monitoring method has a large error in the damage monitoring of steel components. Metal magnetic memory can only effectively judge the early damage of ferromagnetic materials, and can only judge the location of the damage, but cannot identify the size of the damage. In addition, only microscopic defects and early damage can be judged, and late macroscopic damage cannot be identified. Damage monitoring based on acoustic emission is mainly studied in the laboratory environment, and the change of acoustic wave characteristics is relatively weak, so it is easily interfered by high background noise signals in engineering. PVDF sensing technology, fiber Bragg grating strain sensing technology, infrared thermal imaging, high-frequency guided wave, ultrasonic surface wave technology, etc. are difficult to operate in harsh service environments. Surface protection such as paint on steel structures needs to be removed during testing, and signal interference exists And analytical problems, and only the damage location can be identified, and it is difficult to quantify the damage scale.

To sum up, the existing damage monitoring methods for steel structural steel members have the following disadvantages: (1) It is necessary to remove the paint and sheath on the surface of steel structural steel members, which is cumbersome to operate, and it is difficult to serve in complex environments such as acid rain and wind and rain; (2) The position and size of the damage cannot be identified at the same time; (3) Due to the high measurement accuracy and the small range, only microscopic damage can be identified, and the macroscopic damage cannot be identified beyond the range; (4) The measurement accuracy is low and the range is large , only macroscopic damage can be identified, and microscopic damage cannot be effectively identified; (5) microscopic damage and macroscopic damage cannot be identified at the same time, and information about the entire damage process cannot be obtained.

Contents of the invention

Based on this, it is necessary to provide a monitoring system and method for the whole process of steel component damage, aiming at the problems that the traditional section steel monitoring method is cumbersome to operate, cannot identify the whole process of damage, and cannot identify the damage location and damage size at the same time.

A whole-process monitoring system for section steel component damage, including:

The mobile control platform is used to be set on the steel member;

The magnetic sensing probe is arranged on the mobile control platform, and the movement of the mobile control platform drives the magnetic sensing probe to move, so as to obtain the three-dimensional magnetic induction intensity of different positions of the steel member; and

A control system, connected in communication with the mobile control platform and the magnetic sensing probe, to control the work of the mobile control platform and the magnetic sensing probe, and feedback the mobile control platform and the magnetic sensing probe information, and calculate the damage location and damage size of the steel member with time and load development.

In one of the embodiments, the mobile control platform includes a suction cup, a slide table, a first power supply and a first wireless transmission module, the suction cup is used to be adsorbed on the steel member, and the slide table is movably arranged on On the suction cup, the first power supply is electrically connected to the slide table and the first wireless transmission module respectively, and the first wireless transmission module is respectively connected to the slide table and the control system in communication.

In one of the embodiments, the number of the suction cups is two, and the two suction cups are arranged at intervals on the slide table.

In one of the embodiments, the magnetic sensing probe includes a housing, a three-axis magnetic sensor, a second power supply and a second wireless transmission module, the housing is arranged on the mobile control platform, the three-axis magnetic sensor, Both the second power supply and the second wireless transmission module are disposed in the housing, the second power supply is electrically connected to the three-axis magnetic sensor and the second wireless transmission module, and the second wireless The transmission module is communicatively connected with the three-axis magnetic sensor and the control system respectively.

A method for monitoring the damage of a steel component by using the whole process monitoring system for damage of the steel component described in any one of the above, comprising the following steps:

The mobile control platform is arranged on the steel member, with one end of the steel member as the origin, and the length direction of the steel member, that is, the direction from the selected end to the other end, is the Z-axis direction , the width direction of the shaped steel member is the Y-axis direction, the height direction of the shaped steel member is the X-axis direction, and a three-dimensional coordinate system is constructed;

The control system controls the mobile control platform to move along the Z-axis direction, so that the magnetic induction probe obtains the three-dimensional magnetic induction intensity of the steel member, and transmits the three-dimensional magnetic induction intensity to the control system; and

The control system processes the three-dimensional magnetic induction intensity, and further sends signals to adjust the moving speed of the mobile control platform and the sampling frequency of the magnetic induction probe multiple times to obtain the movement of the mobile control platform that matches the damage size. The speed and the sampling frequency of the magnetic induction probe are used to obtain the damage position and damage size of the steel member according to the calculation and processing of the three-dimensional magnetic induction intensity.

In one of the embodiments, the step of calculating the damage position of the steel member by the control system is specifically:

S1) In the Z-axis direction, the moving speed of the mobile control platform is:

u=d _res f

In the formula, d _res is the damage monitoring resolution, u is the moving speed of the mobile control platform, and f is the sampling frequency of the three-axis magnetic sensor in the magnetic sensor probe;

S2) With the development of time and load, a plurality of sampling sequences are formed correspondingly during the movement of the magnetic sensing probe. For the ith sampling sequence, the three-axis magnetic sensor measures the X-axis, Y-axis and Z-axis directions The magnetic induction intensities of are respectively B _x ( _zi ), By _y ( _zi ) and B _z ( _zi ), where the sampling position z _i is:

z _i =(i-1)d _res ;

S3) Calculate the magnetic field gradients B _xz (z _i ), B _yz (z _i ) _of the magnetic induction intensity B x (z i ), B _y (z i ) and B _z ( _{z i )} in the direction of the Z axis at each moment ) and B _zz (z _i ):

S4) Calculate the local contraction of the magnetic field gradients B _xz ( _zi ), _Byz ( _zi ) and B _zz ( _zi ) in the z-axis direction at each moment, which is defined as the local modulus C _Z (zi ₎ :

S5) Determining the damage position of the steel member in the Z-axis direction

and

S6) drawing a relationship curve between C _ZZ (z _i ) and z _i , where the sudden change of the relationship curve is the damage position of the steel member in the Z-axis direction;

S7) The moving speed of the mobile control platform is reduced by half, the sampling frequency of the three-axis magnetic sensor remains unchanged, the value of the damage monitoring resolution d _res is also reduced by 50%, and steps S1)-S6) are repeated. , to obtain a relationship curve between C _ZZ (zi ₎ and _zi , so as to obtain a series of damage positions of the steel member along the Z-axis direction.

In one of the embodiments, the step of calculating the damage size by the control system is specifically:

(1) Locate the damage position as z _j , take the damage position z _j as the center, select a preset length a left and right along the Z-axis direction to form a scanning range [z _j -a, z _j +a];

(2) In the scanning range [z _j -a, z _j + a], the damage monitoring of the steel member is carried out at the damage monitoring resolution d _res0 , then in the scanning range [z _j -a, z The sampling frequency within _j + a] is 2a/d _res0 , and during the first scan within the scanning range [z _j -a, z _j +a], the damage monitoring resolution d _res0 is equal to the damage monitoring resolution rate d _res ;

(3) Calculate the local contraction of the magnetic field gradient at each position in the scanning range [z _j -a, z _j +a] in the direction of the Z axis, defined as the local modulus C _Z (z _k )

z _k =z _j -a+(k-1)d _res0

In the formula, B _xz (z _k ), _Byz (z _k ) and B _zz (z _k ) are the magnetic induction B _x (z _k ), By _y (z _k ) and B _z (z _k ) along Z The magnetic field gradient in the axial direction, where z _k is the sampling position, B _xz (z _k ), B _yz (z _k ) and B _zz (z _k ) are calculated by the above formula (a);

(4) Calculate the second derivative of the local modulus C _Z (z _k ) to z _k :

(5) Reduce the moving speed of the mobile control platform, keep the sampling frequency of the three-axis magnetic sensor unchanged, and repeat the aforementioned (1)-(4) until the scanning range [z _j -a, z The second damage location appears within _j + a], record the sequence numbers of these two damage locations as k=l, k=m, where l<m, and record the corresponding damage monitoring resolution at this time d _res0k , then its positions within [z _j -a, z _j +a] are z _L and z _M respectively; and

(6) At the damage position z _j of the steel member, the corresponding damage size is:

d _zj =(ml)d _res0k .

In one of the embodiments, the profiled steel member is divided into several equal parts along the length direction, and the mobile control platform is respectively arranged on each equalized portion of the profiled steel member to control the entire Z-axis of the profiled steel member. The damage position and the damage size in the direction are monitored, so as to complete the monitoring of the damage position and the damage size in the length direction of the entire steel member.

The above-mentioned whole-process damage monitoring system and monitoring method for steel members can monitor and warn the damage of steel members in complex and harsh service environments such as acid rain and wind-induced vibration, without removing paint and surface sheaths, and does not affect the use and operation of steel structures. Simple. The control system can control the moving speed of the mobile control platform and the sampling frequency of the three-axis magnetic sensor sensor, obtain the moving speed of the control platform and the sampling frequency of the three-axis secondary sensor that match the damage size, and dynamically adjust the damage monitoring resolution, which can be changed Measurement accuracy, so that microscopic damage and macroscopic damage can be identified at the same time, so that the monitoring system can monitor the whole process of damage. Moreover, the whole-process monitoring system for steel member damage can monitor the damage location and damage size at the same time, which can save procedures and improve monitoring efficiency.

Description of drawings

Fig. 1 is a structural schematic diagram of a whole-process monitoring system for medium-sized steel member damage in an embodiment;

Fig. 2 is a schematic structural diagram of the mobile control platform in Fig. 1;

Fig. 3 is a schematic structural diagram of the magnetic sensing probe in Fig. 1;

Fig. 4 is a flow chart of a method for monitoring the whole process of damage of a medium-sized steel member according to an embodiment.

Detailed ways

In order to make the above objects, features and advantages of the present invention more comprehensible, specific implementations of the present invention will be described in detail below in conjunction with the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described here, and those skilled in the art can make similar improvements without departing from the connotation of the present invention, so the present invention is not limited by the specific implementations disclosed below.

It should be noted that when an element is referred to as being “fixed” to another element, it can be directly on the other element or there can also be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and similar expressions are used herein for purposes of illustration only and are not intended to represent the only embodiments.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of the invention. The terms used herein in the description of the present invention are for the purpose of describing specific embodiments only, and are not intended to limit the present invention.

Please refer to FIG. 1 , the whole-process damage monitoring system 10 of a steel member in an embodiment can directly monitor the damage location and damage size in a steel member 20 , and is easy to operate. Specifically, the whole-process monitoring system 10 for steel member damage includes a mobile control platform 100 , a magnetic sensor probe 200 and a control system 300 .

The mobile control platform 100 is used to be arranged on the steel member 20 . The magnetic sensing probe 200 is set on the mobile control platform 100 , and the movement of the mobile control platform 100 drives the magnetic sensing probe 200 to move to obtain the three-dimensional magnetic induction intensity of different positions of the steel member 20 . The control system 300 communicates with the mobile control platform 100 and the magnetic sensor probe 200 to control the work of the mobile control platform 100 and the magnetic sensor probe 200, and calculates and obtains the profile steel according to the information fed back by the mobile control platform 100 and the magnetic sensor probe 200. Damage location and damage size of member 20 as a function of time and loading.

Please also refer to FIG. 2 . Specifically, the mobile control platform 100 includes a suction cup 110 , a sliding platform 120 , a first power supply 130 and a first wireless transmission module 140 . The suction cup 110 is used to absorb on the steel member 20 , so that the entire mobile control platform 100 is arranged on the steel member 20 . In one embodiment, the suction cup 110 is a mechanical vacuum suction cup. The number of suction cups 110 is two, and the two suction cups 110 are arranged at intervals to ensure the stability of the entire mobile control platform 100 . The slide table 120 is movably arranged on the suction cups 110, and the two suction cups 110 can ensure the stability of the slide table 120 movement. The first power supply 130 is electrically connected to the sliding platform 120 and the first wireless transmission module 140 respectively, so as to provide electric energy for the sliding platform 120 and the first wireless transmission module 140 . The first wireless transmission module 140 communicates with the slide table 120 and the control system 300 respectively, so that the control signal sent by the control system 300 can be transmitted to the slide table 120 to control the movement of the slide table 120, and the speed of the slide table 120 transmitted to the control system 300.

Please also refer to FIG. 3 , the magnetic sensing probe 200 includes a housing 210 , a three-axis magnetic sensor 220 , a second power supply 230 and a second wireless transmission module 240 . The casing 210 is disposed on the sliding platform 120 , and the casing 210 of the moving belt of the sliding platform 120 moves. The three-axis magnetic sensor 220 , the second power supply 230 and the second wireless transmission module 240 are all disposed in the housing 210 . The second power supply 230 is respectively electrically connected to the three-axis magnetic sensor 220 and the second wireless transmission module 240 to provide power for the three-axis magnetic sensor 220 and the second wireless transmission module 240 . The second wireless transmission module 240 communicates with the three-axis magnetic sensor 220 and the control system 300 respectively. The second wireless transmission module 240 can transmit the control signal sent by the control system 300 to the three-axis magnetic sensor 220 to control the operation of the three-axis magnetic sensor 220 . Moreover, the three-axis magnetic sensor 220 can transmit the obtained three-dimensional magnetic induction intensity and sampling frequency to the control system 300 .

The control system 300 may be a computer control system 300 . The computer control system 300 can control the moving speed of the sliding table 120 and the sampling frequency of the three-axis magnetic sensor 220 , thereby controlling the damage monitoring resolution of the entire magnetic sensing probe 200 . During the damage monitoring process of the steel member 20, the control system 300 can obtain the three-dimensional magnetic induction intensity monitored by the three-axis magnetic sensor 220, and then the control system 300 can finally obtain the damage location and damage size through a series of calculations.

Please refer to FIG. 4 , the present invention also provides a method for monitoring the whole damage process of the steel member 20 . In order to realize the method for monitoring the whole damage process of the steel member 20, the above-mentioned whole damage monitoring system 10 for the steel member is used. The whole-process monitoring method for steel member damage specifically includes the following steps:

Step S110: Set the mobile control platform 100 on the shaped steel member 20, take one end of the shaped steel member 20 as the origin, and the length direction of the shaped steel member 20, that is, the direction from the selected end to the other end, is the Z axis direction, the width direction of the steel member 20 is the Y-axis direction, the height direction of the steel member 20 is the Z-axis direction, and a three-dimensional coordinate system is constructed.

Specifically, the mobile control platform 100 is arranged on the steel member 20 , and the suction cup 110 is adsorbed and fixed on the steel member 20 , so that the entire mobile control platform 100 is arranged on the steel member 20 . At this time, the three-axis magnetic sensor 220 in the magnetic sensor probe 200 is opposite to the surface of the steel member 20 , so that the three-axis magnetic sensor 220 can obtain the three-dimensional magnetic induction of the steel member 20 . The control system 300 adjusts the position of the slide table 120 so that the magnetic sensor probe 200 is located at the beginning of the steel member 20 , ensuring that the magnetic sensor probe 200 can monitor the entire steel member 20 from beginning to end. In addition, the three-dimensional coordinate system of the three-axis magnetic sensor 220 is consistent with the three-dimensional coordinate system constructed on the steel member 20 .

Step S120 : the control system 300 controls the mobile control platform 100 to move along the Z axis, so that the magnetic sensor probe 200 obtains the three-dimensional magnetic induction of the steel member 20 and transmits the three-dimensional magnetic induction to the control system 300 .

Specifically, the control system 300 sends a signal to the first wireless transmission module 140 in the mobile control platform 100 to remotely control the sliding platform 120 in the mobile control platform 100 to move along the length direction of the steel member 20 . The movement of the sliding table 120 drives the magnetic sensing probe 200 to move, and the magnetic sensing probe 200 also moves accordingly. The three-axis magnetic sensor 220 in the magnetic sensing probe 200 measures the three-dimensional magnetic induction intensity of the steel member 20, and then the magnetic sensing probe The second wireless transmission module 240 in 200 transmits the three-dimensional magnetic induction intensity of the steel member 20 to the control system 300 .

Step 130: The control system 300 processes the three-dimensional magnetic induction intensity, and further sends signals to adjust the moving speed of the mobile control platform 100 and the sampling frequency of the magnetic sensing probe 200 multiple times to obtain the moving speed of the mobile control platform 100 that matches the damage size And the sampling frequency of the magnetic sensing probe 200, according to the calculation and processing of the three-dimensional magnetic induction intensity, the damage position and damage size of the steel member 20 are obtained.

Specifically, the control system 300 processes the three-dimensional magnetic induction intensity of the steel member 20, and then further sends out signals to adjust the moving speed of the mobile control platform 100 and the sampling frequency of the three-axis magnetic sensor 220 in the magnetic sensor probe 200 for multiple times to obtain the same The damage size matches the moving speed of the mobile control platform 100 and the sampling frequency of the three-axis magnetic sensor 220 to dynamically adjust the damage monitoring resolution of the magnetic sensing probe 200 . Finally, according to the three-dimensional magnetic induction intensity, the damage position of the steel member 20 is calculated, and the damage size is calculated according to the damage position.

Specifically, the steps for the control system 300 to calculate the damage position of the steel member 20 are as follows:

S1) In the length direction of the steel member 20, i.e. the Z-axis direction, the moving speed of the mobile control platform 100 is:

u=d _res f

In the formula, d _res is the damage monitoring resolution, u is the moving speed of the mobile control platform 100 in m/s, and f is the sampling frequency of the three-axis magnetic sensor 220 . When testing for the first time, d _res takes 0.001m, f=1000Hz.

S2) Within the movement range of the sliding platform 120 in the mobile control platform 100, the magnetic sensor probe 200 performs high-speed sampling along with the movement of the sliding platform 120 . As time and load develop, the magnetic sensing probe 200 moves from one end of the steel member 20 to the other, correspondingly forming a plurality of sampling sequences. For the i-th sampling sequence, the three-axis magnetic sensor 220 in the magnetic sensor probe 200 measures the magnetic induction in the X-axis, Y-axis and Z-axis directions as B _x (z _i ), B _y (z _i ) and B _z (z _i ), its sampling position z _i is:

z _i =(i−1)d _res .

S3) Calculate the magnetic field gradient of the magnetic induction intensity B _x (z _i ), By _y (z _i ) and B _z (z _i ) in the Z-axis direction at each moment

In the formula, B _xz ( _zi ), _Byz ( _zi ) and B _zz ( _zi ) are the magnetic induction B _x ( _zi ), By _y ( _zi ), B _z ( _zi ) along Z The magnetic field gradient in the axial direction.

S4) Calculate the local contraction of the magnetic field gradients B _xz ( _zi ), _Byz ( _zi ) and B _zz ( _zi ) in the Z-axis direction at each moment, defined as the local modulus C _Z ( _zi ):

S5) Determining the damage position z _i of the steel member 20 in the Z-axis direction

S6) Draw a relationship curve between C _ZZ (z _i ) and _zi , and the sudden change of the relationship curve is the damage position of the steel member 20 in the Z-axis direction.

S7) The moving speed of the sliding table 120 in the mobile control platform 100 is reduced by half, the sampling frequency of the three-axis magnetic sensor 220 remains unchanged, that is, f=1000Hz, and the value of the damage monitoring resolution d _res is also reduced by 50%. , repeat S1)-S6), and obtain multiple curves of C _ZZ (z _i ) and z _i . When there is a sudden change in the curve, the sudden change in the curve is the damage position in the length direction of the steel member 20. At this time, the corresponding damage monitoring resolution d _resi and the moving speed u _i of the mobile control platform 100 are recorded to obtain a series of location of the damage. Wherein, when detecting the damage position, the minimum damage monitoring resolution d _res is 0.000001 m, that is, 1 micron.

After measuring the damaged position of the shaped steel member 20 according to the aforementioned method, the method for calculating the damaged size of the shaped steel member 20 is specifically as follows:

(1) Locate the damage position obtained by the above calculation as z _j , take the damage position z _j as the center, and select a preset length a along the Z-axis direction to form the scanning range [z _j -a, z _j +a]. Specifically, take the damage position z _j as the center, take 0.01m left and right, that is, the scanning range is [z _j -0.01, z _j +0.01].

(2) Within the scanning range [z _j −a, z _j +a], perform damage monitoring on the steel member 20 at a damage monitoring resolution d _res0 . Wherein, the moving speed of the mobile control platform 100 is u ₀ , the sampling frequency of the three-axis magnetic sensor 220 in the magnetic sensor probe 200 is f ₀ =10000Hz, and the sampling frequency is within the scanning range [z _j -a, z _j +a] The frequency is 2a/d _res0 . Wherein, during the first scan within the scanning range [z _j -a, z _j +a], the damage monitoring resolution d _res0 is equal to the damage monitoring resolution d _res .

(3) Perform damage monitoring on the steel member 20 within the scanning range [z _j -a, z _j +a] at the damage monitoring resolution d _res0 . Calculate the local contraction of the magnetic field gradient in the Z-axis direction at each position within the scanning range [z _j -a, z _j +a], defined as the local modulus C _Z (z _k ), where:

z _k =z _j -a+(k-1)d _res0

In the formula, B _xz (z _k ), _Byz (z _k ) and B _zz (z _k ) are the magnetic induction B _x (z _k ), By _y (z _k ) and B _z (z _k ) along Z The magnetic field gradient in the axial direction, where z _k is the sampling position, and B _xz (z _k ), _Byz (z _k ) and B _zz (z _k ) are the same as the previous formulas for calculating the magnetic field gradient, and will not be repeated here.

(4) Calculate the second derivative of the local modulus C _Z (z _k ) with respect to z _k :

(5) Decrease the moving speed u ₀ of the mobile control platform 100 and keep the sampling frequency of the three-axis magnetic sensor 220 unchanged, so the damage monitoring resolution d _res0 will also decrease accordingly. Specifically, if the moving speed u ₀ of the mobile control platform 100 is reduced by half, and the sampling frequency f ₀ of the three-axis magnetic sensor 220 =10000 Hz, the value of the damage monitoring resolution d _res0 is also reduced by 50%. Continuously repeating the aforementioned (1)-(4), the value of the damage monitoring resolution is continuously reduced, that is, the damage monitoring accuracy is continuously improved, and the steel member 20 in the scanning range [z _j -a, z _j +a] is repeatedly detected , until the second damage location appears within the scanning range [z _j -a, z _j +a]. Record the serial numbers of the two damage positions as k=l, k=m, where l<m, and record the corresponding damage monitoring resolution d _res0k at this time, then in the scanning range [z _j -a, z _j + The positions within a] are z _L and z _M , respectively. Wherein, the minimum damage monitoring resolution d _res0 is 0.0000001 m, that is, 0.1 micron.

(6) At the damage position z _j of the steel member 20, the corresponding damage size is:

d _zj =(ml)d _res0k .

The calculation method of the damage size corresponding to other damage positions of the shaped steel member 20 in the Z-axis direction is the same as above, and will not be described in detail here.

In one embodiment, due to the long length of the shaped steel member 20 , the monitoring range of the entire damage process monitoring system 10 for the entire shaped steel member is limited. Therefore, the shaped steel member 20 can be divided into several equal parts along the length direction, and the suction cup 110 of the mobile control platform 100 can be adsorbed and fixed on each equalized shaped steel member 20, and the damage position and damage size of the equal shaped steel member 20 can be monitored. . After the monitoring is completed, the suction cup 110 is disassembled, and then fixedly installed on the next equal portion of the steel member 20 for monitoring, thereby completing the monitoring of the damage position and damage size of the steel member 20 in the longitudinal direction.

The above-mentioned whole-process damage monitoring system 10 for steel members and the damage monitoring method for steel members 20 can monitor and warn the damage of steel members 20 in complex and harsh service environments such as acid rain, wind and rain and vibration, and do not need to remove paint and surface sheaths. It affects the use of steel structures and is easy to operate. The whole-process damage monitoring system 10 for steel members can identify the damage location and damage size at the same time, which can save monitoring procedures and has high efficiency. In addition, the control system 300 adjusts the moving speed of the mobile control platform 100 and the sampling frequency of the three-axis magnetic sensor 220 multiple times to obtain the moving speed of the mobile control platform 100 and the sampling frequency of the three-axis magnetic sensor 220 that match the damage scale. Adjusting the damage monitoring resolution can change the measurement accuracy, so that microscopic damage and macroscopic damage can be identified at the same time, so that the monitoring system can monitor the whole process of damage and has a wide range of applications.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (8)

1. A whole-process monitoring system for section steel member damage, characterized in that it comprises: The mobile control platform is used to be set on the steel member; The magnetic sensing probe is arranged on the mobile control platform, and the movement of the mobile control platform drives the magnetic sensing probe to move, so as to obtain the three-dimensional magnetic induction intensity of different positions of the steel member; and A control system, connected in communication with the mobile control platform and the magnetic sensing probe, to control the work of the mobile control platform and the magnetic sensing probe, and feedback the mobile control platform and the magnetic sensing probe information, and calculate the damage location and damage size of the steel member with time and load development. 2. The whole-process monitoring system for steel member damage according to claim 1, wherein the mobile control platform includes a suction cup, a slide table, a first power supply and a first wireless transmission module, and the suction cup is used to be adsorbed on the On the steel member, the slide table is movably arranged on the suction cup, the first power supply is respectively electrically connected to the slide table and the first wireless transmission module, and the first wireless transmission module is respectively connected to the The slide table and the control system are connected in communication. 3 . The system for monitoring the whole damage process of shaped steel members according to claim 2 , wherein the number of the suction cups is two, and the two suction cups are arranged at intervals on the slide table. 4 . 4. The whole-process monitoring system for steel member damage according to claim 1, wherein the magnetic sensing probe includes a housing, a three-axis magnetic sensor, a second power supply and a second wireless transmission module, and the housing is arranged on On the mobile control platform, the three-axis magnetic sensor, the second power supply and the second wireless transmission module are all arranged in the housing, and the second power supply is connected to the three-axis magnetic sensor and the second wireless transmission module respectively. The second wireless transmission module is electrically connected to the second wireless transmission module, and the second wireless transmission module is respectively connected in communication with the three-axis magnetic sensor and the control system. 5. A method for monitoring the damage of a steel component by using the whole process monitoring system for damage of a steel component as claimed in any one of claims 1 to 4, characterized in that it comprises the following steps: The mobile control platform is arranged on the steel member, with one end of the steel member as the origin, and the length direction of the steel member, that is, the direction from the selected end to the other end, is the Z-axis direction , the width direction of the shaped steel member is the Y-axis direction, the height direction of the shaped steel member is the X-axis direction, and a three-dimensional coordinate system is constructed; The control system controls the mobile control platform to move along the Z-axis direction, so that the magnetic induction probe obtains the three-dimensional magnetic induction intensity of the steel member, and transmits the three-dimensional magnetic induction intensity to the control system; and The control system processes the three-dimensional magnetic induction intensity, and further sends signals to adjust the moving speed of the mobile control platform and the sampling frequency of the magnetic induction probe multiple times to obtain the movement of the mobile control platform that matches the damage size. The speed and the sampling frequency of the magnetic induction probe are used to obtain the damage position and damage size of the steel member according to the calculation and processing of the three-dimensional magnetic induction intensity. 6. The method for monitoring damage of a steel member according to claim 5, wherein the step of calculating the damage position of the steel member by the control system is specifically: S1) In the Z-axis direction, the moving speed of the mobile control platform is: u=d _res f In the formula, d _res is the damage monitoring resolution, u is the moving speed of the mobile control platform, and f is the sampling frequency of the three-axis magnetic sensor in the magnetic sensor probe; S2) With the development of time and load, a plurality of sampling sequences are formed correspondingly during the movement of the magnetic sensing probe. For the ith sampling sequence, the three-axis magnetic sensor measures the X-axis, Y-axis and Z-axis directions The magnetic induction intensities of are respectively B _x ( _zi ), By _y ( _zi ) and B _z ( _zi ), where the sampling position z _i is: z _i =(i-1)d _res ; S3) Calculate the magnetic field gradients B _xz (z _i ), B _yz (z _i ) _of the magnetic induction intensity B x (z i ), B _y (z i ) and B _z ( _{z i )} in the direction of the Z axis at each moment ) and B _zz (z _i ): S4) Calculate the local contraction of the magnetic field gradients B _xz ( _zi ), _Byz ( _zi ) and B _zz ( _zi ) in the z-axis direction at each moment, which is defined as the local modulus C _Z (zi ₎ : S5) Determining the damage position of the steel member in the Z-axis direction and S6) drawing a relationship curve between C _ZZ (z _i ) and z _i , where the sudden change of the relationship curve is the damage position of the steel member in the Z-axis direction; S7) The moving speed of the mobile control platform is reduced by half, the sampling frequency of the three-axis magnetic sensor remains unchanged, the value of the damage monitoring resolution d _res is also reduced by 50%, and steps S1)-S6) are repeated. , to obtain a relationship curve between C _ZZ (zi ₎ and _zi , so as to obtain a series of damage positions of the steel member along the Z-axis direction. 7. The damage monitoring method for steel members according to claim 6, characterized in that the step of calculating and obtaining the damage size by the control system is specifically: (1) Locate the damaged position as z _j , take the damaged position z _j as the center, select a preset length a along the Z-axis direction left and right to form a scanning range [z _j -a, z _j +a]; (2) In the scanning range [z _j -a, z _j + a], the damage monitoring of the steel member is carried out at the damage monitoring resolution d _res0 , then in the scanning range [z _j -a, z The sampling frequency within _j + a] is 2a/d _res0 , and during the first scan within the scanning range [z _j -a, z _j +a], the damage monitoring resolution d _res0 is equal to the damage monitoring resolution rate d _res ; (3) Calculate the local contraction of the magnetic field gradient at each position in the scanning range [z _j -a, z _j +a] in the direction of the Z axis, defined as the local modulus C _Z (z _k ) z _k =z _j -a+(k-1)d _res0 In the formula, B _xz (z _k ), _Byz (z _k ) and B _zz (z _k ) are the magnetic induction B _x (z _k ), By _y (z _k ) and B _z (z _k ) along Z The magnetic field gradient in the axial direction, where z _k is the sampling position, B _xz (z _k ), B _yz (z _k ) and B _zz (z _k ) are calculated by the above formula (a); (4) Calculate the second derivative of the local modulus C _Z (z _k ) to z _k : (5) Reduce the moving speed of the mobile control platform, keep the sampling frequency of the three-axis magnetic sensor unchanged, and repeat the aforementioned (1)-(4) until the scanning range [z _j -a, z The second damage location appears within _j + a], record the sequence numbers of these two damage locations as k=l, k=m, where l<m, and record the corresponding damage monitoring resolution at this time d _res0k , then its positions within [z _j -a, z _j +a] are z _L and z _M respectively; and (6) At the damage position z _j of the steel member, the corresponding damage size is: d _zj =(ml)d _res0k . 8. The damage monitoring method for shaped steel members according to claim 5, wherein the shaped steel member is divided into several equal parts along the length direction, and the mobile control platform is respectively arranged on the shaped steel parts of each equal part. On the member, the damage position and the damage size in the Z-axis direction of the entire shaped steel member are monitored, so as to complete the monitoring of the damage position and damage size in the length direction of the entire shaped steel member.