CN101723246A

CN101723246A - Method for acquiring stress time-domain values of evaluation points by utilizing operating data of bridge crane

Info

Publication number: CN101723246A
Application number: CN200910227828A
Authority: CN
Inventors: 高崇仁; 王守信; 韩玉习; 何洋洋; 田建涛
Original assignee: Taiyuan University of Science and Technology
Current assignee: Taiyuan University of Science and Technology
Priority date: 2009-12-15
Filing date: 2009-12-15
Publication date: 2010-06-09
Anticipated expiration: 2029-12-15
Also published as: CN101723246B

Abstract

The invention relates to a method for acquiring stress time-domain values of evaluation points by utilizing operating data of a bridge crane. The method mainly solves the technical problems of small sample space of acquired data, limited quantity of acquired evaluation point positions and the like existing in conventional bridge cranes. The invention adopts the technical scheme that the method for acquiring the stress time-domain values of the evaluation points by utilizing the operating data of the bridge crane comprises the following steps of: 1) using a data logger to acquire real-time operating data of a crane such as elevating capacity and the like; 2) preprocessing the data; 3) establishing a calculation model of a bridge crane structure; 4) calculating the internal force of a cross-section at certain time; 5) calculating the stress of an evaluation point at certain moment; 6) adding a correction value to or subtracting the correction value from an stress value obtained at certain moment to obtain a corrected stress value; 7) repeating the process to obtain internal forces and corrected stress data which correspond to a plurality of estimation points; and 8) arranging structural internal forces and stress data which are obtained by the calculation and correspond to multiple moments into stress spectrum data.

Description

Method for acquiring stress time domain value of evaluation point by using bridge crane operation data

Technical Field

The invention relates to a method for acquiring a stress time domain value of an evaluation point by utilizing bridge crane operation data, belonging to a method for acquiring stress time domain data of a structure evaluation point by utilizing batch operation data of a bridge crane through rapid calculation.

Background

With the continuous progress of science and technology and the improvement of the safety performance requirement of the bridge crane, the requirement on the safe operation of the bridge crane is higher and higher, and therefore, people do a large amount of work from various aspects, such as strengthening the use management of the operation of the bridge crane, increasing various limiting devices for the safe operation of the bridge crane and the like. However, the problems are not enough, and the main component of the bridge crane, namely the metal structure has fatigue, so that the equipment structure has problems even if the other aspects are in place, and the equipment structure is also a great potential safety hazard for equipment operation. Therefore, the reliability evaluation of the metal structure of the bridge crane is very important for guaranteeing the safe operation of the bridge crane.

However, an important basis for the reliability evaluation of the metal structure of the bridge crane is the stress-time domain data, i.e. the stress spectrum. The stress-time domain data is actual stress data, the data volume of the stress-time domain data is the root cause of influencing the reliability evaluation or fatigue life prediction accuracy, and if a certain amount of data does not serve as the basis, the better and more advanced reliability evaluation or fatigue life prediction theory is just like an aerial pavilion.

At present, data sources for reliability evaluation of a bridge crane are mainly as follows: and (3) measuring the stress of the bridge crane under the action of an external load by sticking strain gauges to corresponding parts on the structure of the bridge crane, and processing the stress to obtain an evaluation conclusion of the crane. Its advantages are simple process; the method has the disadvantages of small space for collecting data samples, limited quantity of collected evaluation point parts, high cost if multi-part long-term collection is carried out, and impracticability in practice.

Disclosure of Invention

The invention aims to solve the technical difficulties of small space of collected data samples, limited quantity of collected evaluation point parts and the like of the conventional bridge crane and provides a method for acquiring a stress time-domain value of an evaluation point by using bridge crane running data, wherein the collected data samples are complete and the quantity of the collected evaluation point parts is large.

The technical scheme adopted by the invention for solving the technical difficulties is as follows: the method for acquiring the stress time domain value of the evaluation point by utilizing the operation data of the bridge crane comprises the following steps:

1) acquiring real-time running data of the lifting capacity, the lifting height and the running positions of a trolley and a cart of the bridge crane by using a data recorder, and storing the acquired real-time running parameters into a storage unit to obtain longer-time running data of the bridge crane;

2) preprocessing the acquired real-time running data for a long time, and according to a speed formula:

and calculating the speed, and then according to the speed and acceleration formula of the two calculated points:

calculating the acceleration to obtain the speed and acceleration parameters of each mechanism;

3) establishing a structural calculation model of the bridge crane, and reading in parameters required by the structural calculation model;

4) calculating the internal force of the upper section of the bridge crane at a certain moment, determining a plurality of section positions of an evaluation point of the bridge crane structure according to evaluation requirements, and calculating the internal force of a plurality of calculation sections on the structure according to the established calculation model;

5) calculating the stress of an evaluation point of the crane at a certain moment, calculating the internal force of a plurality of calculation sections at the certain moment obtained in the step 4), and calculating the structural stress data of the plurality of evaluation points on the plurality of sections at the moment;

6) adding or subtracting a corrected value to or from the stress value obtained in the step 5) at a certain moment to obtain a corrected stress value, wherein the corrected value is in a range of 0-15% of the calculated value;

7) repeating the steps of the step 4), the step 5) and the step 6) to obtain internal force and corrected stress data corresponding to a plurality of evaluation points at a plurality of moments;

8) and 7) organizing the structural internal force and stress data corresponding to a plurality of moments of any point of the bridge crane obtained by calculation in the step 7) into stress spectrum data of a plurality of evaluation points.

The bridge crane data recorder comprises a sensor acquisition device for monitoring bridge crane parameter information, a microprocessing unit, a data storage unit and a communication network interface unit; the signal of the sensor acquisition device of the parameter information is connected with the signal input interface of the micro-processing unit; the data output interface of the microprocessing unit is connected with the input interface of the data storage unit; the input end of the communication network interface unit is connected with the communication output interface of the microprocessing unit.

The sensor acquisition device of the parameter information is composed of a sensor and an analog-to-digital conversion chip, and the output end of the sensor is connected with the input end of the analog-to-digital conversion chip.

Due to the adoption of the technical scheme, the invention solves the technical difficulties of small space for collecting data samples, limited quantity of collected evaluation point parts and the like of the conventional bridge crane. Therefore, compared with the background technology, the method has the advantages of large collected data sample, large quantity of collected evaluation point parts, capability of quickly obtaining stress time domain data of the evaluation points and the like.

Drawings

FIG. 1 is a block flow diagram of the present invention;

FIG. 2 is a block diagram of the data recorder of the bridge crane of the present invention;

FIG. 3 is a schematic view of the calculation of the horizontal direction of the present invention;

FIG. 4 is a schematic view of the calculation of the vertical direction of the present invention;

FIG. 5 is a cross-sectional view of the middle of the main beam of the present invention;

FIG. 6 is a stress spectrum of bending moment-induced stress according to the present invention;

FIG. 7 is a diagram of a global coordinate system X-Y and a local coordinate system X-Y for a unit e according to the present invention;

FIG. 8 is a diagram of a computational model of the present invention for fixed end mechanics;

FIG. 9 is a diagram of a model for calculating bending moment and shearing force according to the present invention.

Detailed Description

The invention is described in further detail below with reference to the figures and examples.

As shown in fig. 1, the method for obtaining the stress time domain value of the evaluation point by using the operation data of the bridge crane comprises the following steps:

2) preprocessing the acquired real-time running data for a long time, and according to a speed formula:and calculating the speed, and then according to the speed and acceleration formula of the two calculated points:

6) adding or subtracting a correction value to or from the stress value obtained in the step 5) at a certain moment to obtain a corrected stress value, wherein the range of the correction value is about 0-15% of the calculated value; the specific value of the corrected value is selected according to the distance between the beam inner partition plate and the like;

As shown in fig. 2, the bridge crane data recorder comprises a sensor acquisition device 1 for monitoring bridge crane parameter information, a microprocessor unit (STC89LE516RD)2, a data storage unit 3 and a communication network interface unit 4; the signal of the sensor acquisition device 1 of the parameter information is connected with the signal input interface of the micro-processing unit 2; the data output interface of the microprocessing unit 2 is connected with the input interface of the data storage unit 3; the input end of the communication network interface unit 4 is connected with the communication output interface of the micro-processing unit 2. The sensor acquisition device 1 for the parameter information is composed of a sensor 1a and an analog-to-digital conversion chip 1b, and the output end of the sensor 1a is connected with the input end of the analog-to-digital conversion chip 1 b.

The method for establishing the bridge crane structure calculation model comprises the following steps: for the vertical plane structure (see fig. 4), the vertical direction structure is simplified into a statically determinate structure and a primary statically indeterminate structure. For the structure of the horizontal plane (see fig. 3), the starting and braking conditions and the support restraint are considered, and the method comprises the following steps: the starting support is symmetrical, the starting support is asymmetrical, the braking support is symmetrical, the braking support is asymmetrical and the like.

The parameters required by the calculation of the read-in structure model are as follows: the following shape parameters obtained through bridge crane engineering drawings or a method for measuring the shape and the size of a bridge crane are obtained: the length of the main girder, the length of the auxiliary girder, the length of the main end girder, the length of the auxiliary end girder, the wheel track of the main trolley, the wheel track of the auxiliary trolley, the track of the main trolley, the track of the auxiliary trolley, the thickness of the main girder web, the height of the main girder web, the thickness of the main girder upper flange plate, the width of the main girder flange plate, the thickness of the auxiliary girder web, the height of the auxiliary girder upper flange plate, the width of the auxiliary girder flange plate, the thickness of the main end girder web, the height of the main end girder web, the thickness of the main end girder upper flange plate, the width of the main end girder flange plate, the thickness of the auxiliary end girder web, the height of the auxiliary end girder web, the thickness of the auxiliary end girder upper flange plate, the width of the auxiliary end girder flange plate and additional data: other data from the bridge crane may be obtained by the manufacturer and manufacturer including: the elastic modulus, the section moment of inertia, the static distance, the dead weight of each mechanism and the like of the material are read into a computer, and model data required by structure calculation are determined.

The parameters required by the read-in structure model calculation include, but are not limited to, main girder, auxiliary girder, main end girder and auxiliary end girder structure parameters, main trolley, auxiliary trolley and other additional data and the like.

The calculation of the internal force of the upper section of the bridge crane at a certain moment comprises the following steps:

calculation of the horizontal plane: according to the technical scheme, the structure of the horizontal plane is a statically indeterminate structure, a force method and a matrix displacement method are adopted for analysis, the effect that the load is any (not more than the rated load) can be obtained through calculation, and when the acting position is any, the internal force of the structure on any section of the horizontal plane can be obtained through calculation.

The method comprises the following steps: the force method calculates the hyperstatic forces and then the internal forces of the structure.

For the statically indeterminate structure, the statically indeterminate structure obtained by removing the redundant relation in the original statically indeterminate structure is called as the basic structure of the force method, and the removed redundant relation is expressed by corresponding redundant unknown force (also called unit force) X_iInstead of working, the following is to solve for the excess unknown force (also called unit force) X_iThe force method coordination equation of (1):

<math><mrow><msub><mi>δ</mi><mi>ij</mi></msub><mo>=</mo><mi>Σ</mi><mo>&Integral;</mo><mfrac><mover><mrow><msub><mi>M</mi><mi>i</mi></msub><msub><mi>M</mi><mi>j</mi></msub></mrow><mo>&OverBar;</mo></mover><mi>EI</mi></mfrac><mi>ds</mi><mo>-</mo><mo>-</mo><mo>-</mo><mrow><mo>(</mo><mn>2</mn><mo>)</mo></mrow></mrow></math>

<math><mrow><msub><mi>Δ</mi><mi>ip</mi></msub><mo>=</mo><mi>Σ</mi><mo>&Integral;</mo><mfrac><mrow><mover><msub><mi>M</mi><mi>i</mi></msub><mo>&OverBar;</mo></mover><msub><mi>M</mi><mi>p</mi></msub></mrow><mi>EI</mi></mfrac><mi>ds</mi><mo>-</mo><mo>-</mo><mo>-</mo><mrow><mo>(</mo><mn>3</mn><mo>)</mo></mrow></mrow></math>

substituting the results calculated by the formulas (2) and (3) into the formula 1 can solve the problemSuper-static fixed force X_i，

M＝M₁X₁+M₂X₂+…+M_iX_i+…+M_nX_n+M_p (4)

And finally, calculating the internal force (bending moment) of the structure through a bending moment synthetic formula (4).

The derivative of the bending moment can obtain the internal force (shearing force) of the structure: q ═ M'

In the above formulas (1), (2), (3) and (4):

n: the number of times of hyperstatic treatment is determined,

i，j：i＝1，2…，n；j＝1，2…，n；

M_i: in the presence of excess unknown force X_iAs 1, the moment diagram of the structure under action (different moment diagrams for different structures cannot be written into the general formula, the same below)

M_j: in the presence of excess unknown force X_j1, the bending moment of the structure under the action of the bending moment diagram,

M_p: a bending moment diagram under the action of an external load P of the structure,

δ_ij: excess unknown force X_i1 and an excess unknown force X_jActing on the basic structure alone, along X_iThe displacement in the direction of the displacement is,

Δ_ip: excess unknown force X_iWith 1 and an external load P acting solely on the basic structure, along X_iThe displacement in the direction of the displacement is,

e: the modulus of elasticity of the material is,

i: and the inertia moment of the cross section is obtained by calculating the shape and the size of the cross section.

The second method comprises the following steps: calculating the rod end force by matrix displacement method, and then calculating the structure internal force

Numbering nodes and cells, selecting global and local coordinates (see FIG. 7)

X-Y is a global coordinate system, X-Y is a local coordinate system, i and j are node numbers, and e is a unit formed by the nodes i and j.

Unit cell	Node (start)	Node (last)
Unit cell	Node (start)	Node (last)	e	I	J

Calculate stiffness matrix for each cell, as shown in FIG. 7

k_{ij}^{e} = [\begin{matrix} \frac{EA}{l} c + \frac{12 EI}{l^{3}} s^{2} & (\frac{EA}{l} - \frac{12 EI}{l^{3}}) cs & - \frac{6 EI}{l^{2}} s & - \frac{EA}{l} c^{2} - \frac{12 EI}{l^{3}} s^{2} & (- \frac{EA}{l} + \frac{12 EI}{l^{3}}) cs & - \frac{6 EI}{l^{2}} s \\ (\frac{EA}{l} - \frac{12 EI}{l^{3}}) cs & \frac{EA}{l} s^{2} + \frac{12 EI}{l^{3}} c^{2} & \frac{6 EI}{l^{2}} c & (- \frac{EA}{l} + \frac{12 EI}{l^{3}}) cs & - \frac{EA}{l} s^{2} - \frac{12 EI}{l^{3}} c & \frac{6 EI}{l^{2}} c \\ - \frac{6 EI}{l^{2}} s & \frac{6 EI}{l^{2}} c & \frac{4 EI}{l} & \frac{6 EI}{l^{2}} s & - \frac{6 EI}{l^{2}} c & \frac{2 EI}{l} \\ - \frac{EA}{l} c^{2} - \frac{12 EI}{l^{3}} s^{2} & (- \frac{EA}{l} + \frac{12 EI}{l^{3}}) cs & \frac{6 EI}{l^{2}} s & \frac{EA}{l} c^{2} + \frac{12 EI}{l^{3}} s^{2} & (\frac{EA}{l} - \frac{12 EI}{l^{3}}) cs & \frac{6 EI}{l^{2}} s \\ (- \frac{EA}{l} + \frac{12 EI}{l^{3}}) cs & - \frac{EA}{l} s^{2} - \frac{12 EI}{l^{3}} c^{2} & - \frac{6 EI}{l^{2}} c & (\frac{EA}{l} - \frac{12 EI}{l^{3}}) cs & \frac{EA}{l} s^{2} + \frac{12 EI}{l^{3}} c & - \frac{6 EI}{l^{2}} c \\ - \frac{6 EI}{l^{2}} s & \frac{6 EI}{l^{2}} c & \frac{2 EI}{l} & \frac{6 EI}{l^{2}} s & - \frac{6 EI}{l^{2}} c & \frac{4 EI}{l} \end{matrix}] - - - (5)

Wherein,

c：cosα，

s：sinα，

α: the angle of the rod member (i, j) to the X-axis in the overall coordinate X-Y,

a: the cross-sectional area of the rod member,

e: the modulus of elasticity of the rod member is,

l: the length of the rod member is such that,

i: the moment of inertia of the rod member is,

i, j: the node number of the rigid frame, i, j is 2, 3, …, n, n is the total number of nodes, and an original rigidity matrix, namely a total rigidity matrix, is formed

When i is j, i.e. the matrix of cells on the main diagonal in equation (6), is determined by the superposition of the stiffness matrices of the relevant cells of node i (or j), i.e. the matrix of cells on the main diagonal is obtained

When i ≠ j, and i, j are correlation points, that is the stiffness matrix of the corresponding cell joining their cells; when i ≠ j, and i, j is a non-relevant node,

k_{ij}^{e} = 0 .

calculating the end fixing force, equivalent node load and comprehensive node load

Since the structural unit may be externally loaded, a fixed end force is required, as shown in figure 8,

N_i＝0

N_j＝0

q: the uniform external load generated on the unit, as shown in figure 8,

l: the length of the unit, as shown in figure 8,

p1, P2: the concentrated external load acting on the unit, as shown in figure 8,

modifying the original stiffness equation based on the support conditions

Wherein:

P_{i} = \{\begin{matrix} X_{i} \\ Y_{i} \\ M_{i} \end{matrix}\}

in equation (7): p_iExternal force column vector, X, representing node i_i，Y_iAnd M_iExternal force and external couple acting on the node i in x and y directions, respectively, namely: the solid end force N obtained above_i，Q_i，M_i。

Δ_iA displacement column vector, u, representing a node i_i，v_iAnd phi_iRespectively the linear displacement and the angular displacement of the node i along the x and y axes of the structure coordinate system.

P₁，··P_i，··P_nOnly including the known node displacement, Δ₁，··Δ_i，··Δ_nIncluding only unknown nodal displacements, the stiffness matrix K at that time_{Repair the}I.e. the rows and columns corresponding to the node displacements known to be zero are deleted from the original stiffness matrix of the structure, called the stiffness matrix of the structure, or called the reduced total stiffness.

The rod end force of each unit rod is calculated.

By the formula

The rod end force of the unit is obtained,

P_ij ^e: the column vector represents the rod end forces of the i, j nodes of the unit e, including axial force, shearing force, bending moment,

k_ij ^e: the stiffness matrix, representing e of the cell, see equation (6),

Δ_ij ^e: the displacement of the i, j node representing cell e is a column vector, which has been solved from equation (7).

The structural internal force is calculated from the calculated rod end force, as shown in figure 9,

when x is more than or equal to 0 and less than a,

bending moment: when a is less than or equal to x and less than a + c,

when a + c is less than or equal to x is less than or equal to L,

when x is more than or equal to 0 and less than a, Q is-Q_i+q·x

Shearing force:

when a is less than or equal to x and less than a + c，Q＝-Q_i+q·x+P1

When a + c is less than or equal to x and less than or equal to L, Q is-Q_i+q·x+P1+P2

Wherein M is_i，Q_iThat is, the calculated rod end force.

Calculation of the vertical plane: the computational model is simplified into a simple beam (as in figure 4),

calculating the wheel pressure of the trolley: pv1 ═ Pv2 ═ weight (hanging weight + self-weight of gourd) × 9.8 × 0.5 (8)

The support reaction force is determined from the force balance:

R1＝Pv1·a+Pv2·(a+c)+qL-R1 (9)

and (3) solving the internal force of the middle section of the main beam according to the support counter force and the small wheel pressure:

bending moment after the uniform load and the concentrated load are superposed:

when x is L, namely the position of the middle section of the main beam (10)

Shear (shear is the derivative of bending moment):

the stress of the crane evaluation point at a certain moment is calculated as follows: calculating the internal force of a plurality of cross sections at a certain moment obtained in the step, and calculating the structural stress data of a plurality of evaluation points on the plurality of cross sections at the moment;

stress calculation in horizontal plane

Stress due to bending moment:

stress due to shearing force:

stress calculation in vertical plane

Stress due to bending moment:

shear stress by shear force:

in equations (12), (13), (14), and (15): bending moment in the M-horizontal plane, shear force in the Q-horizontal plane, M_vBending moment in the vertical plane, Q_vShear in the vertical plane, S-girder mid-section static moment, delta-girder web thickness, I_xMoment of inertia in the X-direction of the median section of the girder, X_cCenter of section x of the beam in the middle, I_yMoment of inertia in the x-direction of the median section of the girder, Y_cThe centre of the girder in the direction x of its median section.

And (3) stress synthesis:

the combined bending stress is obtained by algebraic addition of the stresses generated by the bending moment in the horizontal direction in the vertical direction, and the combined shear stress is obtained by algebraic addition of the stresses generated by the shearing force.

And (3) bending moment synthesis: sigma_{Synthesis of}＝σ_{Is perpendicular to}+σ_{Level of}+σ_Correction (16)

Shear force synthesis: tau is_{Synthesis of}＝τ_{Is perpendicular to}+τ_{Level of}+τ_Correction (17)

In the formula: sigma_Correction、τ_CorrectionThe range of the corrected value is about 0-15% of the calculated value, and the specific value of the corrected value is selected according to factors such as the distance between the beam and the inner partition plate.

The following specific examples:

taking a single-girder bridge crane as an example, the internal force and the stress of any plurality of sections and any plurality of points are calculated, in order to explain the rapid calculation method, only the stress calculation process of the point shown on the midspan section is selected, the internal force of the section is calculated, then the stress of the point is calculated, and the external load action results at different moments can be calculated according to the external loads applied at different moments. The specific shape and section parameters are as follows: shape parameters, cross-sectional parameters and other parameters are as given in the table:

selecting a calculation point:

the middle section of the girder (as shown in figure 3, the position of the middle section of the girder is at the position L/2 in figure 4, and the middle section is shown in figure 5)

The x' direction moment of inertia is: 2.5X 10⁹mm⁴

The moment of inertia in the y' direction is: 4.229X 10⁹mm⁴

The centroid coordinates are: xc 330.7mm, Yc 783.6mm

Cross-sectional area: 397900 mm ^2

The calculation points are: (0, 0) point (as in fig. 5) under the initial coordinate, in fig. 5, x-y is the initial coordinate, the establishment is arbitrary, determined according to the convenience; x '-y' is a coordinate axis with the centroid of the cross section as the origin, and Xc, Yc are position values relative to the initial coordinates in actual calculation.

The following table 1 shows the sling and operating data.

Firstly, the method comprises the following steps: the internal force and stress in the vertical direction are calculated.

Simplifying the calculation model into a simple supported beam (as shown in figure 4), and finding out the position a of the trolley on the main beam according to the table 1 (one moment);

calculating the wheel pressure of the trolley: pv1 ═ Pv2 ═ weight of hoist + self weight of hoist x 9.8 × 0.5

＝(10000+3000)×9.8×0.5＝6.37×10⁴N

The support reaction force is determined from the force balance:

= 25152 N

bending moment after the uniform load and the concentrated load are superposed:

where x is L, i.e. the position of the central section of the girder

Shearing force:

shear being the derivative of bending moment

= - 51287 N

Second, the horizontal internal force and stress are calculated.

Since the bridge crane travels in the horizontal direction, inertial force is generated in the horizontal plane, and the acceleration of the cart is 0.12m/s according to the calculation model shown in fig. 3 and table 1.

1. The horizontal inertial load is:

(wherein P1, P2 are wheel pressure Pv1, inertia load of Pv2 generated in horizontal direction, q is inertia load of main beam self weight generated in horizontal direction)

2. The structure in the horizontal direction is calculated schematically as shown in FIG. 3

According to the formula 1, 2

δ₁₁X₁+Δ_1p＝0

<math><mrow><msub><mi>δ</mi><mn>11</mn></msub><mo>=</mo><mi>Σ</mi><mo>&Integral;</mo><mfrac><mrow><mover><msub><mi>M</mi><mn>1</mn></msub><mo>&OverBar;</mo></mover><mover><msub><mi>M</mi><mn>1</mn></msub><mo>&OverBar;</mo></mover></mrow><mi>EI</mi></mfrac><mi>ds</mi><mo>=</mo><mfrac><mn>2</mn><mn>3</mn></mfrac><msup><mi>k</mi><mn>3</mn></msup><mo>+</mo><mi>L</mi><mo>·</mo><msup><mi>k</mi><mn>2</mn></msup><mo>=</mo><mn>15.6</mn><msup><mi>m</mi><mn>3</mn></msup></mrow></math>

The concentrated load acting alone, according to equation (3)

<math><mrow><msub><mi>Δ</mi><mrow><mn>1</mn><mi>p</mi></mrow></msub><mo>=</mo><mi>Σ</mi><mo>&Integral;</mo><mfrac><mrow><mover><msub><mi>M</mi><mn>1</mn></msub><mo>&OverBar;</mo></mover><mover><msub><mi>M</mi><mi>p</mi></msub><mo>&OverBar;</mo></mover></mrow><mi>EI</mi></mfrac><mi>ds</mi><mo>=</mo><mn>10920</mn><mi>N</mi><mo>·</mo><msup><mi>m</mi><mn>3</mn></msup></mrow></math>

Obtaining the bending moment of the cross section according to the formula (4):

M_p＝M₁X₁+M_p＝-1×700+780×7.5＝5150N·m

Q_p＝M′_p＝-780N

the uniform load acts independently according to the formula 3

<math><mrow><msub><mi>Δ</mi><mrow><mn>1</mn><mi>p</mi></mrow></msub><mo>=</mo><mi>Σ</mi><mo>&Integral;</mo><mfrac><mrow><mover><msub><mi>M</mi><mn>1</mn></msub><mo>&OverBar;</mo></mover><mover><msub><mi>M</mi><mi>p</mi></msub><mo>&OverBar;</mo></mover></mrow><mi>EI</mi></mfrac><mi>ds</mi><mo>=</mo><mfrac><mn>1</mn><mn>2</mn></mfrac><mo>×</mo><mn>62.27</mn><mo>×</mo><mfrac><msup><mn>7.5</mn><mn>3</mn></msup><mn>3</mn></mfrac><mo>×</mo><mn>15</mn><mo>×</mo><mn>1</mn><mo>=</mo><mn>66150</mn><mi>N</mi><mo>·</mo><mi>m</mi></mrow></math>

Obtaining the bending moment of the cross section according to the formula (4):

<math><mrow><msub><mi>M</mi><mi>q</mi></msub><mo>=</mo><mover><msub><mi>M</mi><mn>1</mn></msub><mo>&OverBar;</mo></mover><msub><mi>X</mi><mn>1</mn></msub><mo>+</mo><msub><mi>M</mi><mi>p</mi></msub><mo>=</mo><mo>-</mo><mn>1</mn><mo>×</mo><mn>4240</mn><mo>+</mo><mfrac><mn>1</mn><mn>2</mn></mfrac><mo>×</mo><mn>62.72</mn><mo>×</mo><msup><mn>7.5</mn><mn>2</mn></msup><mo>=</mo><mo>-</mo><mn>2467</mn><mi>N</mi><mo>·</mo><mi>m</mi></mrow></math>

Q_q＝M′_q＝-1746N

superposition of bending moment and shearing force generated by concentrated load and uniformly distributed load

Bending moment: m is M_p+M_q＝-5150-2467＝-7617N·m

Shearing force: q ═ Q_p+Q_q＝-780-1746＝2526N

Thirdly, calculating the stress of the point and the composition of the stress

In the vertical direction

Positive stress due to bending moment:

shear stress by shear force:

horizontal direction according to the formulas (12), (13)

Stress due to bending moment:

stress due to shearing force:

And (3) bending moment synthesis: sigma_{Synthesis of}＝σ_{Is perpendicular to}+σ_{Level of}+σ_Correction＝-101-5.596+0.0＝106.596Mpa

Shear force synthesis: tau is_{Synthesis of}＝τ_{Is perpendicular to}+τ_{Level of}+τ_Correction＝-1.4-0.433+0.0＝-1.833Mpa

σ in the above embodiment_Correction、τ_CorrectionThe values are all taken as 0.0.

The calculation results are shown in Table 2 as the calculated internal force and in Table 3 as the calculated stress. The correction values in the stress here each take 0.0.

TABLE 1

Hoisting weight	Acceleration of lifting	Position of the carriage	Acceleration of cart
Hoisting weight	Acceleration of lifting	Position of the carriage	Acceleration of cart	10000Kg	0m/s²	10000mm	0.012m/s

TABLE 2

Bending moment in the vertical direction	Shear force in vertical direction	Horizontal bending moment	Horizontal direction shearing force
Bending moment in the vertical direction	Shear force in vertical direction	Horizontal bending moment	Horizontal direction shearing force	-32115Nm	-51287N	-9951Nm	-545.8N

TABLE 3

Bending stress in vertical direction	Shear stress in the vertical direction	Bending stress in horizontal direction	Shear stress in horizontal direction	Synthesis of bending moments	Composition of shear forces
Bending stress in vertical direction	Shear stress in the vertical direction	Bending stress in horizontal direction	Shear stress in horizontal direction	Synthesis of bending moments	Composition of shear forces	-101MPa	-1.4MPa	-5.596MPa	-0.433MPa	-106.596MPa	-1.833MPa

Fourthly, similarly, from the above example process, the stress values at different times of the points obtained under the external load at each time in table 4 below can be obtained, and the results are detailed in table 5.

TABLE 4

Time of day	Hoisting weight	Acceleration of lifting	Position of the carriage	Acceleration of cart
Time of day	Hoisting weight	Acceleration of lifting	Position of the carriage	Acceleration of cart	2009-6-3’8:15:15	10000Kg	0m/s²	1000mm	0m/s²
2009-6-3’8:16:45	10000Kg	0m/s²	5000mm	0m/s²	2009-6-3’8:15:15	10000Kg	0m/s²	1000mm	0m/s²
2009-6-3’8:16:45	10000Kg	0m/s²	5000mm	0m/s²	2009-6-3’8:17:00	10000Kg	0m/s²	7500mm	0m/s²
2009-6-3’8:17:30	10000Kg	0m/s²	10000mm	0m/s²	2009-6-3’8:17:00	10000Kg	0m/s²	7500mm	0m/s²
2009-6-3’8:17:30	10000Kg	0m/s²	10000mm	0m/s²	2009-6-3’8:18:45	10000Kg	0m/s²	12000mm	0m/s²
2009-6-3’8:19:00	10000Kg	0m/s²	10000mm	0m/s²	2009-6-3’8:18:45	10000Kg	0m/s²	12000mm	0m/s²
2009-6-3’8:19:00	10000Kg	0m/s²	10000mm	0m/s²	2009-6-3’8:19:15	10000Kg	0m/s²	7500mm	0m/s²
2009-6-3’8:19:30	10000Kg	0m/s²	5000mm	0m/s²	2009-6-3’8:19:15	10000Kg	0m/s²	7500mm	0m/s²
2009-6-3’8:19:30	10000Kg	0m/s²	5000mm	0m/s²	2009-6-3’8:19:45	10000Kg	0m/s²	1000mm	0m/s²

The stress at these 9 times was determined by the same method as above:

TABLE 5

Time of day	Bending moment in vertical direction	Shear force in vertical direction	Horizontal bending moment	Horizontal direction shearing force	Synthesis of bending moments	Composition of shear forces
Time of day	Bending moment in vertical direction	Shear force in vertical direction	Horizontal bending moment	Horizontal direction shearing force	Synthesis of bending moments	Composition of shear forces	2009-6-3’8:15:15	-83.3MPa	-3.9MPa	0MPa	0MPa	-83.3MPa	-3.9MPa
2009-6-3’8:16:45	-152MPa	-5.4MPa	0MPa	0MPa	-152MPa	-5.4MPa	2009-6-3’8:15:15	-83.3MPa	-3.9MPa	0MPa	0MPa	-83.3MPa	-3.9MPa
2009-6-3’8:16:45	-152MPa	-5.4MPa	0MPa	0MPa	-152MPa	-5.4MPa	2009-6-3’8:17:00	-174.3MPa	-4MPa	0MPa	0MPa	-174.3MPa	-4MPa
2009-6-3’8:17:30	-154MPa	-2.5MPa	0MPa	0MPa	-154MPa	-2.5MPa	2009-6-3’8:17:00	-174.3MPa	-4MPa	0MPa	0MPa	-174.3MPa	-4MPa
2009-6-3’8:17:30	-154MPa	-2.5MPa	0MPa	0MPa	-154MPa	-2.5MPa	2009-6-3’8:18:45	-116MPa	-1.33MPa	0MPa	0MPa	-116MPa	-1.33MPa
2009-6-3’8:19:00	-154MPa	-2.5MPa	0MPa	0MPa	-154MPa	-2.5MPa	2009-6-3’8:18:45	-116MPa	-1.33MPa	0MPa	0MPa	-116MPa	-1.33MPa
2009-6-3’8:19:00	-154MPa	-2.5MPa	0MPa	0MPa	-154MPa	-2.5MPa	2009-6-3’8:19:15	-174.3MPa	-4MPa	0MPa	0MPa	-174.3MPa	-4MPa

Time of day	Bending moment in vertical direction	Shear force in vertical direction	Horizontal bending moment	Horizontal direction shearing force	Synthesis of bending moments	Composition of shear forces
Time of day	Bending moment in vertical direction	Shear force in vertical direction	Horizontal bending moment	Horizontal direction shearing force	Synthesis of bending moments	Composition of shear forces	2009-6-3’8:19:30	-152MPa	-5.4MPa	0MPa	0MPa	-152MPa	-5.4MPa
2009-6-3’8:19:45	-83.3MPa	-3.9MPa	0MPa	0MPa	-83.3MPa	-3.9MPa	2009-6-3’8:19:30	-152MPa	-5.4MPa	0MPa	0MPa	-152MPa	-5.4MPa

It is particularly noted that for large batches of load data, the stress values at different times can be rapidly calculated according to the above method. In addition, for the calculation of the internal force of the horizontal plane of the bridge crane, the calculation of the internal force of the statically indeterminate rigid frame of the horizontal plane of the bridge crane can be solved by using a second method, namely a matrix displacement method, and the same result can be obtained by using the above example of the matrix displacement method.

And fifthly, drawing a stress time domain graph of the point according to the stress data obtained by calculation. In this example, a time domain graph of bending stress, i.e. a stress spectrum, resulting from the bending moment synthesis for the period of time can be made according to table 5, as shown in fig. 6.

Claims

1. A method for acquiring a stress time domain value of an evaluation point by using bridge crane operation data is characterized by comprising the following steps:

2. The method for obtaining the stress time domain value of the evaluation point by using the operation data of the bridge crane as claimed in claim 1, wherein: the bridge crane data recorder comprises a sensor acquisition device for monitoring bridge crane parameter information, a microprocessing unit, a data storage unit and a communication network interface unit; the signal of the sensor acquisition device of the parameter information is connected with the signal input interface of the micro-processing unit; the data output interface of the microprocessing unit is connected with the input interface of the data storage unit; the input end of the communication network interface unit is connected with the communication output interface of the microprocessing unit.

3. The method for obtaining the stress time domain value of the evaluation point by using the operation data of the bridge crane as claimed in claim 2, wherein: the sensor acquisition device of the parameter information is composed of a sensor and an analog-to-digital conversion chip, and the output end of the sensor is connected with the input end of the analog-to-digital conversion chip.