Safety warning method and system for support beam of inner climbing tower crane self-lifting device

Abstract

The application provides a support beam safety early warning method and system of an inner climbing tower crane self-lifting device, and relates to the field of civil engineering, which comprises the following steps: installing a support beam of a lifting device on a tower crane standard section, and installing a plurality of stress sensors on the support beam; collecting strain data of the support beam as known data, and performing the following calculations: calculating the maximum stress of a dangerous point of the support beam; calculating a confidence interval of future dangerous point stress according to the known data; obtaining a new group of sensor data after a new lifting process, calculating the actual maximum stress of the dangerous point according to the new sensor data, calculating the theoretical maximum stress value under the current load, calculating the upper limit of the confidence interval of this lifting process, and issuing a danger warning if the calculated actual maximum stress exceeds the confidence interval or exceeds the allowable stress value of the steel structure. The application improves the lifting efficiency of the inner climbing tower crane foundation beam, and designs an early warning method to ensure safety.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building engineering, in particular to a support beam safety early warning method and system of an inner climbing tower crane self-lifting device. BACKGROUND

[0002] For super high-rise reinforced concrete structures such as cable-stayed bridge main towers, the lifting technology of tower cranes is very important. The efficiency and safety of tower crane lifting have a great influence on the efficiency of on-site construction and the construction period. In the traditional tower crane jacking process, other tower cranes need to be occupied to assist in transporting the foundation beam, which causes both tower cranes to be unable to work normally during this process. In addition, the inner space of the inner climbing tower crane is small, the operation is difficult, and the transportation time is long. Using the inner climbing tower crane self-lifting device for jacking operation has gradually become a new trend. However, for the inner climbing tower crane self-lifting device, how to ensure the safety of the lifting process becomes a technical problem to be solved. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art or related art, and discloses a support beam safety early warning method and system of an inner climbing tower crane self-lifting device, which improves the efficiency and safety of tower crane jacking.

[0004] The first aspect of the present application discloses a support beam safety early warning method of an inner climbing tower crane self-lifting device, comprising: installing a support beam of a lifting device on a tower crane upper standard section, installing a plurality of stress sensors on both ends of the flange of the support beam and in the middle of the support beam, the support beam being a quadrilateral with a cantilever end, and the lifting device comprising an electric hoist; before safety detection, collecting a plurality of groups of strain data of the support beam as known samples, calculating the actual maximum stress of the dangerous point of the support beam according to the sensor data, calculating the confidence interval of the future dangerous point stress according to the average value and the standard error of a plurality of actual maximum stresses, and calculating the normalized value of the confidence interval; obtaining a new group of sensor data after a new lifting process, calculating the actual maximum stress of the dangerous point according to the new sensor data , calculating the theoretical maximum stress value under the current load according to the load data of the electric hoist , and calculating the upper limit of the confidence interval of this lifting process according to the theoretical maximum stress value and the normalized value .

[0005] When , it is determined that the support beam is in a safe state, wherein, represents the allowable stress value of the steel structure; and when , a danger warning is issued.

[0006] The support beam safety early warning method of the inner climbing type tower crane self-lifting device disclosed in the application preferably comprises the following steps:

[0007] ;

[0008] wherein, represents the actual maximum stress of the dangerous point, and E represents the elastic modulus of the support beam, represents the maximum value of the stress sensor;

[0009] The calculation process of the average value and the standard error of the actual maximum stress comprises the following steps:

[0010] ;

[0011] ;

[0012] wherein, represents the average value of all sample stresses, represents the stress value of each sample, n represents the number of samples, and SE represents the standard error of the sample data;

[0013] The calculation process of the confidence interval of the future dangerous point stress comprises the following steps:

[0014] Setting a confidence level t: the confidence level t is determined according to the importance of the structure, and the probability that the prediction data is less than the upper limit of the confidence interval is determined by the following formula:

[0015] ;

[0016] wherein, T represents the probability that the prediction data is less than the upper limit of the confidence interval, and t represents the confidence level;

[0017] Calculating the upper limit and the lower limit of the confidence interval:

[0018] ;

[0019] ;

[0020] wherein, a represents the lower limit of the confidence interval, b represents the upper limit of the confidence interval, and z represents a standard score, and the value of z is obtained from a standard score table according to the specific value of T;

[0021] The process of calculating the normalized value of the confidence interval comprises the following steps:

[0022] ;

[0023] ;

[0024] ;

[0025] wherein, represents the theoretical maximum stress value under the actual load, F represents the actual force of the electric hoist, represents the distance between the electric hoist mounting point and the support beam mounting point, y represents the distance from the calculation section of the steel structure to the neutral layer, represents the moment of inertia of the steel structure around the strong axis; A represents the lower limit of the normalized confidence interval, and B represents the upper limit of the normalized confidence interval;

[0026] Upper limit of the confidence interval The calculation process specifically includes:

[0027] ;

[0028] wherein, B represents the upper limit of the normalized confidence interval, represents the theoretical maximum stress value under the actual load.

[0029] According to the support beam safety warning method of the inner climbing tower crane self-lifting device disclosed in the application, preferably, when it is determined that the support beam is in a safe state, the normalized confidence interval of the new set of data is added to the database, and the upper and lower limits of the confidence interval of the past data are weighted and averaged, so that the confidence interval can dynamically change.

[0030] ;

[0031] ;

[0032] wherein, represents the upper and lower limits of the normalized confidence interval calculated after the new data is added, represents the upper and lower limits of the normalized confidence interval of the existing data, represents the upper and lower limits of the normalized confidence interval of the new data, represents the sample size of the existing data and the new data.

[0033] According to the support beam safety warning method of the inner climbing tower crane self-lifting device disclosed in the application, preferably, the determination process of the support beam parameters specifically includes:

[0034] The maximum stress point on the support beam is the position of the support point, and the maximum bending moment borne by the support beam is determined by the following formula:

[0035] ;

[0036] wherein, M represents the maximum bending moment borne by the support beam, F represents the force used for lifting by the electric hoist, l a represents the distance between the electric hoist mounting point and the support beam mounting point;

[0037] The dimensions of the support beam are determined using the following formula:

[0038] ;

[0039] ;

[0040] ;

[0041] in, This indicates the yield strength of the selected steel, and K represents the structural safety factor. This indicates the allowable stress value of the steel structure. The theoretical maximum stress at the critical point is represented by , M represents the maximum bending moment on the supporting beam, and y represents the distance between the calculated section and the neutral layer. This represents the moment of inertia of the supporting beam about the strong axis.

[0042] According to the safety early warning method for the support beam of the self-lifting device of the internal climbing tower crane disclosed in this invention, preferably, the support beam is an I-beam, K is 3, y=h / 2, and h is the cross-sectional height of the I-beam.

[0043] According to the safety early warning method for the support beam of the self-lifting device of the internal climbing tower crane disclosed in this invention, preferably, the connection method between the support beam and the tower crane includes: installing embedded parts on the standard section of the tower crane; installing cantilever brackets on the embedded parts; and anchoring the support beam and the cantilever brackets with bolts.

[0044] The method for safety early warning of the support beam of the self-lifting device of the internal climbing tower crane disclosed in this invention preferably further includes: data visualization: using a programming language to visualize the stress data of the connection point of the support beam and generate a stress monitoring diagram.

[0045] The safety early warning method for the support beam of the self-lifting device of the internal climbing tower crane disclosed in this invention preferably further includes: early warning information push: sending the danger warning to a mobile terminal.

[0046] A second aspect of the present invention discloses a support beam safety early warning system for an internal climbing tower crane self-lifting device, comprising: a memory for storing program instructions; and a processor for calling the program instructions stored in the memory to implement the support beam safety early warning method for the internal climbing tower crane self-lifting device as described in any of the above technical solutions.

[0047] The beneficial effects of the present invention include at least the following: the present invention proposes to install a self-lifting device on the upper standard section of the tower crane for lifting the foundation beam, and proposes a support beam design scheme and a safety early warning method for the self-lifting device. In addition, a safety early warning system is designed for the self-lifting device, which improves the efficiency and safety of tower crane lifting. Attached Figure Description

[0048] Figure 1 Fig. 13 shows a schematic diagram of an internal climbing tower crane self-lifting process according to an embodiment of the present application.

[0049] Figure 2 Fig. 14 shows a schematic diagram of a flow of a support beam safety early warning method of an internal climbing tower crane self-lifting device according to an embodiment of the present application.

[0050] Figure 3 Fig. 15 shows a schematic diagram of a support beam structure according to an embodiment of the present application.

[0051] Figure 4 Fig. 16 shows a schematic diagram of a support beam stress simplified model according to an embodiment of the present application.

[0052] Figure 5 Fig. 17 shows a schematic diagram of a sensor position according to an embodiment of the present application.

[0053] Figure 6 Fig. 18 shows a schematic diagram of existing strain data according to an embodiment of the present application.

[0054] Figure 7 Fig. 19 shows a schematic diagram of new strain data according to an embodiment of the present application.

[0055] Figure 8 Fig. 20 shows a schematic diagram of stress data according to an embodiment of the present application.

[0056] Figure 9 Fig. 21 shows a schematic diagram of data visualization according to an embodiment of the present application.

[0057] Figure 10 Fig. 22 shows a schematic diagram of a support beam safety early warning system of an internal climbing tower crane self-lifting device according to an embodiment of the present application. DETAILED DESCRIPTION

[0058] In order to more clearly understand the above-mentioned purposes, features and advantages of the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. In the following description, a large number of specific details are set forth in order to facilitate a full understanding of the present application, however, the present application can also be implemented in other ways different from those described herein, therefore, the present application is not limited to the specific embodiments disclosed below.

[0059] As Figure 1As shown, the inner climbing tower crane self-climbing mainly includes base beam lifting and tower body jacking. A base beam is arranged at the bottom of the tower body of the inner climbing tower crane, two base beams are arranged in the middle, and the base beam on the upper side of the middle is not stressed when the tower crane is working. A support beam is arranged on the upper part of the tower body, and an electric hoist is installed on the beam. When the tower crane is lifted, the base beam on the upper side of the middle is lifted by the electric hoist, and after the beam is installed, the connection between the tower body and the base beam at the bottom of the tower body is loosened, and the two base beams on the upper part are stressed. Then the second step-tower body jacking is carried out, the tower body is jacked up by the hydraulic device at the bottom, then the base beam at the bottom of the tower body is fixed, the base beam on the lower side of the middle is lifted by the electric hoist on the support beam, and the self-climbing of the tower crane is completed. In order to ensure the reliability and safety of self-climbing, a support beam safety warning method of the self-lifting device of the inner climbing tower crane needs to be developed to timely warn possible risks.

[0060] As shown in the drawings, Figure 2 According to one embodiment of the present application, a support beam safety warning method of a self-lifting device of an inner climbing tower crane is disclosed, comprising:

[0061] I. Support beam design:

[0062] Support beam form determination: according to the overall construction deployment of the construction project, the tower crane model and the tower crane inner cylinder size, the form and size of the support beam are determined (as shown in Figure 3 The structure of the support beam is a quadrilateral with a cantilever end, and the length of the cantilever end needs to meet the needs of lifting the base beam. The support beam is installed on the standard section of the tower crane, and the form of installing the embedded part on the standard section and installing the cantilever corbel on the embedded part is adopted, and the support beam and the corbel are connected by bolt anchoring.

[0063] II. Model simplification:

[0064] Stress model simplification: a structure stress model simplification method is proposed, which simplifies the support beam of the lifting device into a stress member with stiffness and strength but no size in structural mechanics, and its connection with the tower crane standard section is simplified as rigid connection. The support beam is a symmetrical structure, and its half can be simplified as an elongated beam in structural mechanics. It is easy to know that the point with the maximum stress on the beam is the position of the support, and the bending moment is determined by formula (1):

[0065] M = F * L; (1)

[0066] Where: M represents the maximum bending moment of the support beam; F represents the force used by the electric hoist for lifting; L represents the distance between the electric hoist installation point and the support beam installation point.

[0067] Support beam size determination: a support beam size determination method is proposed, which assumes that the support beam is an I-beam, and selects an appropriate size of I-beam according to formulas (2), (3) and (4). ​

[0068] (2)

[0069] (3)

[0070] (4)

[0071] In the formula: represents the yield strength of the selected steel material; K represents the safety factor of the structure; represents the allowable stress value of the steel structure; represents the theoretical maximum stress of the dangerous point; M represents the maximum bending moment of the support beam; y represents the distance from the calculation section to the neutral layer (for I-beams, y = 0.5h) , h represents the height of the I-beam section; represents the moment of inertia of the I-beam around the strong axis.

[0072] Three, sensor selection and installation:

[0073] Considering the actual situation of the tower crane lifting, the strain sensor (stress sensor) needs to be selected as a wireless passive stress sensor, and a strain sensor with long battery life can also be used. According to the knowledge of material mechanics, the sensor only needs to be installed at the most dangerous point of the most dangerous section. Considering that the model has been simplified as an elongated beam, it is only necessary to install it at the flange of the support point. One sensor can be installed at each end of the flange and in the middle, and the maximum value is taken as the stress calculation value.

[0074] Four, data analysis:

[0075] A data processing method is proposed. Before safety detection, some strain data should be collected as known data. EXCEL calculation table is used to compile calculation formula to realize one-key processing of raw data. The calculation steps include:

[0076] Stress calculation: the maximum stress of the dangerous point of the support beam is calculated by formula (5);

[0077] (5)

[0078] In the formula: represents the actual maximum stress of the dangerous point; E represents the elastic modulus of the support beam (which can be taken as 2.06 × 10 5 Mpa); represents the maximum value of the stress sensor;

[0079] If , do not perform the subsequent steps, and replace another set of known data for calculation.

[0080] Calculation of fluctuation threshold: Based on previous actual measurement data, the confidence interval of future critical stress points can be calculated through the following steps:

[0081] Calculate the mean and standard error of the sample: As can be seen from the actual situation of the project, the sample size of stress is relatively large and should conform to a normal distribution. First, the strain data can be converted into stress data by equation (5). The mean and standard error of all stress data can be calculated by equations (6) and (7);

[0082] (6)

[0083] (7)

[0084] In the formula: This represents the average stress across all samples. This represents the stress value for each sample; n represents the number of sample points; SE represents the standard error of the sample data.

[0085] Determine the confidence level and standard score: The confidence level is determined according to the importance of the structure, and the probability T of the predicted data being less than the upper limit of the confidence interval can be determined by equation (8);

[0086] (8)

[0087] In the formula: T represents the probability that the predicted data is less than the upper limit of the confidence interval; t represents the confidence level (0~1).

[0088] Determine the upper and lower values ​​of the confidence interval: The upper and lower values ​​of the confidence interval can be obtained by equations (9) and (10);

[0089] (9)

[0090] (10)

[0091] In the formula: a represents the lower limit of the confidence interval; b represents the upper limit of the confidence interval; z represents the standard score;

[0092] The standard score z can be obtained according to the table below. Find the z corresponding to T in the table. For example, when... hour, The value of z is 1.96. Table 1 is a table of z values ​​for the standard normal distribution. The horizontal axis of the table header represents the second decimal place, and the vertical axis represents the integer part and the first decimal place. The values ​​in the table are the probabilities T of the standard normal distribution when the value is less than z. The sum of the horizontal and vertical axes corresponding to this probability T is z.

[0093] Table 1 Standard Score Value Table

[0094]

[0095] Data normalization: the theoretical value of the dangerous point stress under a certain load can be obtained from equation (11), the upper and lower limits of the confidence interval under this load can be obtained from equations (9) and (10), and the data normalization can be completed by equations (12) and (13) as follows:

[0096] (11)

[0097] (12)

[0098] (13)

[0099] In the formula: represents the theoretical maximum stress value under the actual load; F represents the actual force of the electric hoist;

[0100] represents the distance between the installation point of the electric hoist and the installation point of the support beam, y represents the distance from the calculated section of the steel structure to the neutral layer, represents the moment of inertia of the steel structure around the strong axis; A represents the lower limit of the normalized confidence interval; B represents the upper limit of the normalized confidence interval;

[0101] Five, data research and judgment:

[0102] A new set of data is obtained after the new lifting process, the actual maximum stress is calculated by equation (5) ; the theoretical maximum stress value under the current load is calculated by equation (11) ; and the upper limit of the confidence interval of this process is calculated by equation (14)

[0103] (14)

[0104] A safety warning method is proposed, when , it can be considered that the device is safe, otherwise a danger warning should be issued.

[0105] A threshold updating method is proposed, the normalized confidence interval of the new data meeting the requirements is added to the database, and the upper and lower limits of the confidence interval are weighted averaged with the upper and lower limits of the past data confidence interval by equations (15) and (16), so that the confidence interval is always changing. The frequency of adding new data can be set as required.

[0106] (15)

[0107] (16)

[0108] In the formula: represents the upper and lower limits of the normalized confidence interval calculated after adding new data; represent the upper and lower limits of the confidence interval of the existing data normalization; represent the upper and lower limits of the confidence interval of the new data normalization; represent the sample size of the existing data and the new data;

[0109] Six, data visualization: use programming language to visualize data, and write a mobile client to facilitate users to receive warning information in time and conveniently.

[0110] According to another embodiment of the application, the above embodiment is also disclosed in the actual engineering project, including:

[0111] Step one: design of the support beam of the lifting device;

[0112] Support beam form determination

[0113] According to the overall construction deployment of the construction project, the tower crane model and the tower crane inner cylinder size, the support beam of the lifting device is selected as a quadrilateral with a cantilever end as shown in the drawing, wherein the long side (including the cantilever end) is 5000mm long, the short side is 2700mm long, and the electric hoist suspension point is 1000mm away from the bolt connection point. Figure 2

[0114] Simplification of structure stress model

[0115] The support beam of the lifting device is simplified as a stress member with stiffness and strength but without size in structural mechanics, and its connection with the tower crane standard section is simplified as a rigid connection. The support beam is a symmetrical structure, and its half can be simplified as an elongated beam in structural mechanics (as shown in the drawing). It is easy to know that the point with the maximum stress on the beam is the position of the support, and the bending moment is determined by formula (1): Figure 4

[0116] (1)

[0117] Select an electric hoist with a maximum lifting weight of 5 tons:

[0118] ;

[0119] Determination of support beam size:

[0120] Assuming that the support beam is an I-beam. The appropriate size of the I-beam can be selected according to formulas (2), (3) and (4):

[0121] (2)

[0122] (3)

[0123] (4) ​​

[0124] The steel grade Q345 is selected, and the safety factor K is 3.

[0125] The limit stress is determined by formula (2):

[0126] ;

[0127] According to the national standard for hot-rolled steel (GB / T 706-2016), steel I30a is selected ( ), and the maximum stress of the dangerous point is calculated by formula (3):

[0128] ;

[0129] The calculation is verified by formula (4):

[0130] ;

[0131] It meets the requirements.

[0132] Step two: selection and installation of sensors;

[0133] As shown in Figure 5 , considering the actual situation of the tower crane lifting, WSMC1 series wireless strain module is selected, which includes supporting the use of wireless Ethernet to transmit data. One strain gauge is installed at each end of the flange and in the middle. Each strain gauge transmits strain data through a channel, and the maximum value is taken as the stress calculation value.

[0134] Step three: data processing;

[0135] Stress calculation:

[0136] After one lifting, it is known that the weight of the lifted object is 3 tons, and the strain gauge returns the data as shown in Figure 6 . It is easy to get the maximum strain , and the maximum stress of the dangerous section can be obtained by formula (5):

[0137] (5)

[0138] ;

[0139] It meets the conditions and can be followed by subsequent calculations.

[0140] Calculation of fluctuation threshold:

[0141] Combining the previously measured data, the confidence interval of the stress of the future dangerous point can be calculated by the following steps.

[0142] Calculate the mean and standard error of the sample:

[0143] From the actual situation of the project, the sample size of stress is large and should be in accordance with the normal distribution. First, the strain data can be converted to stress data (as shown in FIG. 5) by formula (5). Figure 8

[0144] The average value of all stress data can be calculated by formula (6):

[0145] (6)

[0146]

[0147] The standard error of all stress data can be calculated by formula (7):

[0148] (7)

[0149]

[0150] Determine the confidence level and standard score:

[0151] The confidence level is taken according to the importance of the structure, and in this case, it is taken as . The probability T that the predicted data is less than the upper limit of the confidence interval can be determined by formula (8):

[0152] (8)

[0153] ;

[0154] The standard score z can be taken according to the table in step three, and .

[0155] Calculate the upper and lower values of the confidence interval:

[0156] The upper and lower values of the confidence interval can be obtained by formula (9) (10)

[0157] (9)

[0158] (10)

[0159] ;

[0160] Data normalization:

[0161] The theoretical value of the stress of the dangerous point under a specific load can be obtained by formula (11), the upper and lower limits of the confidence interval under the load are obtained by formula (9) (10), and the normalization of the data can be completed by the following formula (12) (13) to make the data effective under different loads.

[0162] (11)​

[0163] ;

[0164] (12)

[0165] ;

[0166] (13)

[0167] ;

[0168] Step four: data analysis and visualization;

[0169] Data analysis: after the new lifting process, a new set of data is obtained as shown in Figure 7 , at this time the weight of the heavy object is 2 tons, and the maximum strain is , the actual maximum stress is calculated using equation (5);

[0170] ;

[0171] The theoretical maximum stress value under the current load is calculated using equation (11) ;

[0172] ;

[0173] Finally, the upper limit of the confidence interval of this process is calculated using equation (14)

[0174] (14)

[0175] ;

[0176] At this time , so it can be determined that the lifting device is in a safe state during the process, and no warning needs to be issued.

[0177] At the same time, according to the process in step three, the normalized confidence interval of the new data at a confidence level of 0.95 is calculated as:

[0178] ;

[0179] ;

[0180] Add the normalized confidence interval of this set of new data to the database, and use equations (15) and (16) to do a weighted average of the upper and lower limits of the confidence interval with the upper and lower limits of the past data confidence interval:

[0181] (15)

[0182] ;

[0183] (16)

[0184] ;;

[0185] As Figure 9 shown, the data visualization: data is visualized by using programming language, wherein 3 channels correspond to strain data of 3 strain gauges respectively, and the result shows that the strain of 3 measuring points is less than the upper limit of confidence interval, so it can be determined that the lifting device is in a safe state during the process, and no early warning is needed.

[0186] As Figure 10 shown, according to another embodiment of the application, a support beam safety early warning system 900 of the self-lifting device of the inner climbing tower crane is also disclosed, comprising: a memory 901 for storing program instructions; a processor 902 for calling the program instructions stored in the memory to realize the support beam safety early warning method of the self-lifting device of the inner climbing tower crane as described above.

[0187] To sum up, according to the construction engineering structure form and the tower crane parameters, the lifting load of the electric hoist is determined, the related parameters are calculated, the size, material and the like of the support beam of the lifting device are designed, and finally the design of the support beam of the self-lifting device and the early warning system thereof is completed through a certain data processing method. The application not only solves the problems of long occupied time of the lifting efficiency of the traditional inner climbing tower crane foundation beam and the like, but also guarantees the safety of the designed early warning system.

[0188] All or part of the steps of various methods of the above embodiments can be completed by a program controlling relevant hardware, and the program can be stored in a readable storage medium, including Read-Only Memory (ROM), Random Access Memory (RAM), Programmable Read-only Memory (PROM), Erasable Programmable Read Only Memory (EPROM), One-time Programmable Read-Only Memory (OTPROM), Electrically-Erasable Programmable Read-Only Memory (EEPROM), Compact Disc Read-Only Memory (CD-ROM) or other optical disk storage, magnetic disk storage, magnetic tape storage, or any other readable medium capable of carrying or storing data.

[0189] The above description is merely preferred embodiments of the present application, and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, and the like made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A safety early warning method for the support beam of an internal climbing tower crane self-lifting device, characterized in that, include: A support beam for installing a lifting device is installed on the upper standard section of the tower crane. Multiple stress sensors are installed at both ends of the flange of the support beam and in the middle of the support beam. The support beam is a quadrilateral with a cantilever end. The lifting device includes an electric hoist. Before conducting safety inspections, multiple sets of strain data of the support beam are collected as known samples. The actual maximum stress at the critical point of the support beam is calculated based on the sensor data. The confidence interval of the future critical point stress is calculated based on the average value and standard error of multiple actual maximum stresses. The normalized value of the confidence interval is then calculated. A new set of sensor data was obtained after the new lifting process, and the actual maximum stress at the critical point was calculated based on the new sensor data. The theoretical maximum stress value under the current load is calculated based on the load data of the electric hoist. According to the theoretical maximum stress value The upper limit of the confidence interval for this boosting process is calculated using the normalized value. ; when At that time, it was determined that the support beam was in a safe state, among which, This indicates the allowable stress value of the steel structure; when At that time, a danger warning will be issued.

2. The safety early warning method for the support beam of the self-lifting device of the internal climbing tower crane according to claim 1, characterized in that, The process of calculating the actual maximum stress at the danger point based on sensor data specifically includes: ； in, The value represents the actual maximum stress at the critical point, and E represents the elastic modulus of the supporting beam. This indicates the maximum value of the stress sensor. The calculation process for the average value and standard error of the actual maximum stress includes: ； ； in, This represents the average stress of all samples. This represents the stress value for each sample, where n represents the number of samples, and SE represents the standard error of the sample data. The calculation process for the confidence interval of future critical point stress specifically includes: Set the confidence level t: The confidence level t is chosen according to the importance of the structure, and the probability that the predicted data is less than the upper limit of the confidence interval is determined by the following formula: ； Where T represents the probability that the predicted data is less than the upper limit of the confidence interval, and t represents the confidence level; Calculate the upper and lower limits of the confidence interval: ； ； Where a represents the lower limit of the confidence interval, b represents the upper limit of the confidence interval, and z represents the standard score. The value of z is obtained from the standard score value table based on the specific value of T. The process of calculating the normalized value of a confidence interval specifically includes: ； ； ； in, This represents the theoretical maximum stress value under actual load, where F represents the actual force on the electric hoist. The distance between the electric hoist installation point and the support beam installation point is represented by y, where y represents the distance from the calculated section of the steel structure to the neutral layer. A represents the moment of inertia of the steel structure about the strong axis; B represents the lower limit of the normalized confidence interval and C represents the upper limit of the normalized confidence interval. Upper limit of confidence interval The calculation process specifically includes: ； Where B represents the upper limit of the normalized confidence interval. This represents the theoretical maximum stress value under actual load.

3. The safety early warning method for the support beam of the self-lifting device of the internal climbing tower crane according to claim 2, characterized in that, Also includes: Once the support beam is determined to be in a safe state, the normalized confidence interval of this new data is added to the database, and a weighted average is taken with the upper and lower limits of the confidence intervals of past data, allowing the confidence interval to change dynamically. ； ； in, This represents the upper and lower limits of the normalized confidence interval calculated after adding new data. This represents the upper and lower limits of the confidence interval for normalized existing data. This represents the upper and lower limits of the confidence interval for normalized new data. This indicates the sample size of existing data and new data.

4. The safety early warning method for the support beam of the self-lifting device of the internal climbing tower crane according to claim 1, characterized in that, The process of determining the parameters of the supporting beam specifically includes: The point of maximum stress on the support beam is the location of the support point, and the maximum bending moment on the support beam is determined by the following formula: ； Where M represents the maximum bending moment on the supporting beam, F represents the force used by the electric hoist to lift, and l a This indicates the distance between the electric hoist installation point and the support beam installation point; The dimensions of the support beam are determined using the following formula: ； ； ； in, This indicates the yield strength of the selected steel, and K represents the safety factor of the structure. This indicates the allowable stress value of the steel structure. The theoretical maximum stress at the critical point is represented by , M represents the maximum bending moment on the supporting beam, and y represents the distance between the calculated section and the neutral layer. This represents the moment of inertia of the supporting beam about the strong axis.

5. The safety early warning method for the support beam of the self-lifting device of the internal climbing tower crane according to claim 4, characterized in that, The supporting beam is an I-beam, the value of K is 3, y = h / 2, and h is the cross-sectional height of the I-beam.

6. The method for safety early warning of the support beam of the self-lifting device of the internal climbing tower crane according to claim 1, characterized in that, Also includes: Data visualization: Using programming languages, stress data at the connection points of the support beams can be visualized to generate stress monitoring charts.

7. The safety early warning method for the support beam of the self-lifting device of the internal climbing tower crane according to claim 1, characterized in that, Also includes: Warning information push: Send danger warnings to mobile devices.

8. A safety early warning system for the support beam of an internal climbing tower crane self-lifting device, characterized in that, include: Memory, used to store program instructions; A processor is configured to invoke the program instructions stored in the memory to implement the support beam safety early warning method for the self-lifting device of the internal climbing tower crane as described in any one of claims 1 to 7.

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