An assembled power transmission foundation contact stress detection device and detection method

Abstract

The application provides an assembled power transmission foundation contact stress detection device and a detection method, which comprise protective clamps, sensors, steel supports and sliding rails, the bottom end of the steel support is slidably arranged on the sliding rail, the sliding rail is detachably arranged on the top surface of the assembled power transmission foundation, the protective clamps are suspended on the steel support through telescopic thin steel columns, the sensors are arranged in the protective clamps, and the sensors are connected with a data acquisition system, the stress detection method can comprehensively detect the contact stress between the assembled modules of the assembled power transmission foundation, facilitates analysis of whether the assembled power transmission foundation has defects, provides a reference for contact stress measurement of various assembled power transmission foundations, and also provides a basis, meanwhile, the application adopts a method of selecting measurement points to test the contact stress value, and a stress distribution map is drawn in combination with an interpolation method, so that the measurement efficiency is improved, and the stress detection precision and the accuracy of the stress distribution map drawing are improved.

Description

Technical Field

[0001] This invention relates to the field of power transmission foundation testing devices, specifically to a prefabricated power transmission foundation contact stress testing device and testing method. Background Technology

[0002] In the construction of power projects such as high-voltage overhead transmission lines, foundation construction is necessary. Transmission foundations include prefabricated foundations and cast-in-place foundations. Prefabricated foundations are more convenient to construct and install, and are currently the most widely used. After the design of a prefabricated transmission foundation is completed, designers need to conduct design tests to ensure that its performance is essentially the same as that of a cast-in-place foundation. In addition to controlling the strength, stiffness, stability, durability, and other indicators of the prefabricated foundation to be the same as those of the cast-in-place foundation, the tests also need to consider the contact stress state between the modules, as prefabricated foundations are assembled from various modules, unlike the integrated structure of cast-in-place foundations. Furthermore, due to the different assembly and fixing methods of various types of prefabricated transmission foundations, there are instances where the upper or lower surfaces of the components become points of contact stress concentration. Therefore, to ensure that during normal use, the prefabricated transmission foundation will not experience partial component failure or overall damage due to excessive contact stress, the contact stress between the prefabricated foundation modules needs to be tested and analyzed.

[0003] However, in current engineering practice, the devices used to test power transmission foundations generally do not take into account the contact stress between prefabricated power transmission foundation modules. It is difficult to fully ensure the performance qualification of prefabricated power transmission foundations during design and testing. Therefore, there is an urgent need for a device that can detect the contact stress between prefabricated power transmission foundation modules. Summary of the Invention

[0004] To address the problems existing in the background technology, the present invention proposes a prefabricated power transmission foundation contact stress detection device, including a protective clip, a sensor, a steel bracket and a slide rail. The bottom end of the steel bracket is slidably mounted on the slide rail, and the slide rail is detachably installed on the top surface of the prefabricated power transmission foundation. The protective clip is suspended on the steel bracket by a telescopic thin steel column. The sensor is installed in the protective clip and is connected to a data acquisition system.

[0005] Preferably, the sensor includes a mechanical sensor and an LVDT displacement sensor.

[0006] Preferably, the protective clip is made of two steel plates welded together.

[0007] A method for detecting contact stress in prefabricated power transmission foundations includes the following steps:

[0008] S1: Assemble the prefabricated power transmission foundation at the construction site, and set the slide rail mounting holes on the prefabricated power transmission foundation. After the prefabricated power transmission foundation is assembled, fix the slide rail of the detection device to the prefabricated power transmission foundation through the slide rail mounting holes.

[0009] S2: Insert the sensor of the detection device into the gap between the contact surfaces of the assembled modules of the prefabricated power transmission foundation. The sensor moves in the vertical and horizontal directions through the slide rail and the telescopic thin steel column. The mechanical sensor tests the contact stress value at each point of the contact surface in sequence and uses the detected contact stress value as the initial value.

[0010] S3: Utilize LVDT displacement sensors to measure the vertical and horizontal displacement distances of the detection device, obtain the position of the detected point in real time, and determine the location of the maximum contact stress.

[0011] S4: The LVDT displacement sensor and mechanical sensor transmit the detected data to the data acquisition system. The data acquisition system exports the contact stress values ​​and corresponding stress locations at the contact surfaces of each assembly module in real time and draws a stress distribution diagram.

[0012] S5: Apply load to the prefabricated power transmission foundation, repeat the operation steps of S2, and measure the change of contact stress value at the contact surface of each assembly module after simulating the actual load.

[0013] S6: Repeat steps S3 and S4 to obtain the stress distribution diagram and the location of the maximum contact stress after the load is applied.

[0014] Preferably, in step S2, the contact stress value is tested by selecting measurement points. During testing, the top surface of the prefabricated power transmission foundation is used as a reference. A measurement point A1 is selected by moving 8cm downwards in the vertical direction, and the contact stress value at measurement point A1 is measured. From measurement point A1, the measurement point A2 is selected by moving 8cm downwards in the same vertical direction, and the contact stress value at measurement point A2 is measured. The absolute value of the stress change 'a' between measurement points A1 and A2 is used as a control variable. A measurement point C is selected by moving downwards in the same vertical direction. If the absolute value of the stress change 'a' is less than 1MPa, then when selecting measurement point A3, measurement point A3 is aligned with... The distance between measuring points A2 is 5cm. If the absolute value of the stress change a is greater than 1MPa, then when selecting measuring point A3, the distance between measuring point A3 and measuring point A2 should be 8cm. Then, continue to move downwards along the same vertical direction to select measuring point A4. At this time, the absolute value of the stress change between measuring point A3 and measuring point A4 is used as the control variable, and the distance between measuring point A4 and measuring point A3 is determined according to the above principle. In this way, measuring points are selected downwards in sequence, and the control variable is the absolute value of the stress change between the two measuring points before the measuring point to be selected.

[0015] Following the principle of selecting the measurement spacing between measuring points in the vertical direction, the same principle of controlling the absolute value of stress change between two measuring points is applied in the horizontal direction. After completing the first vertical direction test, the position of the last measuring point An in the first vertical direction is moved 8cm horizontally to determine the position of the first measuring point B1 in the second vertical direction. Stress testing is then performed in the second vertical direction. Measuring points are selected by moving upwards from measuring point B1 in the second vertical direction, following the same principle as in the vertical direction. After completing the second vertical direction test, the position of the last measuring point Bn in the second vertical direction is moved horizontally to select the third... The position of the first measuring point C1 in the vertical direction is determined. At this point, the absolute value of the stress change b between A1 and Bn is used as the control variable. If the absolute value of the stress change b is greater than 1MPa, the distance between measuring point C1 and measuring point Bn is 8cm when measuring point C1 is selected. If the absolute value of the stress change b is less than 1MPa, 0.75MPa, 0.5MPa, 0.4MPa, and 0.25MPa respectively, the distance between measuring point C1 and measuring point Bn is 20mm, 10mm, 7.5mm, 5mm, and 3mm respectively when measuring point C1 is selected. The test is carried out in this manner. When the absolute value of the stress change is less than or equal to 0.2MPa, the minimum measurement interval of 2mm is selected.

[0016] Interpolation was used to determine the values ​​between two adjacent measuring points, and a continuous and complete stress distribution diagram was drawn.

[0017] Preferably, the stress distribution map is drawn using the interpolation method. A subroutine for calculating the interpolation is written using MATLAB, and four interpolations are selected between every two measuring points to reduce the error between the calculated stress value and the actual value.

[0018] Preferably, the subroutine for calculating the interpolation is:

[0019] n = input('Please enter the number of interpolations n=');

[0020] start_point=input('Please enter the starting point coordinates X1=');

[0021] finish_point=input('Please enter the coordinates of the final point X2=');

[0022] increments=input('Please enter the distance L between two adjacent measurement points=');

[0023] [rm]=size(C);

[0024] node=r*m;

[0025] if node ~= 2*(n+2)

[0026] error('The number of nodes is insufficient')

[0027] end

[0028] if n <= 0

[0029] error('Insufficient input parameters')

[0030] end

[0031] for j = 3:n+3

[0032] for i = j-1:n+2

[0033] C(i,j)=(C(i,j-1)-C(i-1,j-1)) / (C(i,1)-C(i+2-j,1));

[0034] end

[0035] end

[0036] for x = start_point:increments:finish_point

[0037] y = 0;

[0038] S = 1;

[0039] for i = 1:n+2

[0040] for j = i-1:-1:1

[0041] S = S*(x-C(j,1));

[0042] end

[0043] y = y+C(i,i+1)*S;

[0044] end

[0045] disp(['X: ',num2str(x)]);

[0046] disp(['Y: ',num2str(y)]);

[0047] K = 1;R = 1;

[0048] for i = 1:n+1

[0049] K = K*(x-C(i,1));

[0050] end

[0051] R = abs(C(n+2,n+3)*K)

[0052] end

[0053] The zero coordinate point is where the top surface of the prefabricated power transmission foundation intersects with the first vertical direction. The vertical direction is the Y coordinate, with the vertical downward direction being the positive Y coordinate direction and the horizontal direction being the X coordinate. During the X-direction measurement, the movement is unidirectional, and the direction of movement is the positive X coordinate direction.

[0054] Preferably, in step S5, after measuring the initial contact stress of the prefabricated power transmission foundation, the sensor is promptly removed from the gap between the contact surfaces of the assembly modules to prevent the sensor from being crushed or damaged. The measurement spacing when simulating actual load is consistent with the measurement spacing when measuring the initial contact stress.

[0055] The present invention has the following beneficial effects:

[0056] 1. This invention can detect the contact stress of prefabricated power transmission foundations. Based on the detected stress values ​​and stress cloud diagrams, the contact stress between the assembled modules of the prefabricated power transmission foundation can be obtained, which facilitates the analysis of whether there are defects in the prefabricated power transmission foundation and provides a reference and basis for the measurement of contact stress of various prefabricated power transmission foundations.

[0057] 2. This invention uses a method of selecting measurement points to test contact stress values, and combines this with an interpolation method to draw a stress distribution map, which improves measurement efficiency and the accuracy of stress detection and stress distribution map drawing.

[0058] 3. This invention uses steel clips to protect the LVDT sensor and the mechanical sensor, preventing the sensor tip from directly contacting the concrete surface to avoid crushing damage and experimental errors; at the same time, it uses a slide rail for longitudinal movement measurement, which increases the applicability of the detection device to prefabricated power transmission foundations. Attached Figure Description

[0059] Figure 1 This is a schematic diagram of the overall structure of the detection device of the present invention;

[0060] Figure 2 This is a schematic diagram of the distribution of measuring points in this invention;

[0061] Figure 3 This is a schematic diagram of the detection device of the present invention installed on a prefabricated power transmission foundation;

[0062] Figure 4 This is a schematic diagram of the detection method of the present invention.

[0063] The numbers in the diagram are: 1-protective clip, 2-sensor, 3-steel bracket, 4-thin steel column, 5-slide rail, 6-contact surface gap, 7-assembly module. Detailed Implementation

[0064] To make the present invention clearer and more understandable, the technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the given embodiments are only one of the implementation methods and do not represent all embodiments.

[0065] Combined with appendix Figures 1-4 A prefabricated power transmission foundation contact stress detection device includes a protective clip 1, a sensor 2, a steel bracket 3, and a slide rail 5. The bottom end of the steel bracket 3 is slidably mounted on the slide rail 5, and the slide rail 5 is detachably mounted on the top surface of the prefabricated power transmission foundation. The protective clip 1 is suspended on the steel bracket 3 by a telescopic thin steel column 4. The sensor 2 is installed in the protective clip 1 and is connected to a data acquisition system.

[0066] Specifically, the sensor 2 includes a mechanical sensor and an LVDT displacement sensor.

[0067] Specifically, the protective clip 1 is made of two steel plates welded together to form a steel clip, which is used to protect the sensor 2. During detection, the sensor 2 follows the steel clip into the contact surface gap 6 between the assembly modules 7. The steel clip can prevent the sensor 2 from being damaged. During installation, mounting holes are provided on the steel plates, and the sensor 2 is fixed between the steel clips by binding with cable ties or fixing with bolts.

[0068] More specifically, the thin steel column 4 can adopt a nested hollow structure to achieve retractability. The sensor 2 is connected to the data acquisition system through a data transmission line. The outer wall of the data transmission line can be covered by a rubber tube to protect the data transmission line. After the data transmission line is connected to the sensor 2, it passes through the hollow of the thin steel column 4, extends out of the upper end of the thin steel column 4, and then connects to the data acquisition system.

[0069] A method for detecting contact stress in prefabricated power transmission foundations includes the following steps:

[0070] S1: Assemble the prefabricated power transmission foundation at the construction site and set the slide rail mounting holes on the prefabricated power transmission foundation. After the prefabricated power transmission foundation is assembled, fix the slide rail 5 of the testing device to the prefabricated power transmission foundation through the slide rail mounting holes. The slide rail mounting holes can be prefabricated or opened on the assembly site. Use pneumatic nails or rubber nails to fix the slide rail 5 in conjunction with the slide rail mounting holes. The prefabricated power transmission foundation is mainly assembled by concrete modules (i.e., assembly modules 7). The slide rail mounting holes are small in size and will not damage or affect the concrete modules. The slide rail 5 can be disassembled and installed at any time to change the direction of the slide rail 5 in the horizontal direction, such as the horizontal and vertical directions, so that the testing device can fully cover the contact surface of the assembly module 7 for testing. When installing the slide rail 5, ensure that there is a complete contact surface gap 6 between the two slide rails 5.

[0071] S2: Insert the sensor 2 of the detection device into the contact surface gap 6 between the assembled modules 7 of the prefabricated power transmission foundation. The sensor 2 moves in the vertical and horizontal directions through the slide rail 5 and the telescopic thin steel column 4. The mechanical sensor tests the contact stress value at each point of the contact surface in sequence and uses the detected contact stress value as the initial value.

[0072] S3: Utilize LVDT displacement sensors to measure the vertical and horizontal displacement distances of the detection device, obtain the position of the detected point in real time, and determine the location of the maximum contact stress.

[0073] S4: The LVDT displacement sensor and mechanical sensor transmit the detected data to the data acquisition system. The data acquisition system exports the contact stress values ​​and corresponding stress locations at the contact surfaces of each assembly module 7 in real time, and draws a stress distribution diagram. The data acquisition system can store the detection data for easy real-time viewing of the detection results.

[0074] S5: Apply load to the prefabricated power transmission foundation, repeat the operation steps of S2, and measure the change of contact stress value at the contact surface of each assembly module 7 after simulating the actual load.

[0075] S6: Repeat steps S3 and S4 to obtain the stress distribution diagram and the location of the maximum contact stress after the load is applied.

[0076] Specifically, in step S2, the contact stress value is tested by selecting measurement points. During the test, the top surface of the prefabricated power transmission foundation is used as a reference. The measurement point A1 is selected by moving 8cm downwards vertically. The contact stress value at measurement point A1 is measured. From measurement point A1, the measurement point A2 is selected by moving 8cm downwards vertically. The contact stress value at measurement point A2 is measured. The absolute value 'a' of the stress change between measurement points A1 and A2 is used as a control variable. The measurement point C is selected by moving downwards vertically. If the absolute value 'a' of the stress change is less than 1MPa, then when selecting measurement point A3, measurement point A3 is aligned with measurement point A1. The distance between the two points is 5cm. If the absolute value of the stress change a is greater than 1MPa, then when selecting measuring point A3, the distance between measuring point A3 and measuring point A2 should be 8cm. Then, continue to move downwards along the same vertical direction to select measuring point A4 (not shown in the figure). At this time, the absolute value of the stress change between measuring point A3 and measuring point A4 is used as the control variable, and the distance between measuring point A4 and measuring point A3 is determined according to the above principle. In this way, measuring points are selected downwards in sequence, and the control variable is the absolute value of the stress change between the two measuring points before the measuring point to be selected.

[0077] Following the principle of selecting the measurement spacing between measuring points in the vertical direction, the same control method of absolute stress change between two measuring points is used in the horizontal direction. After completing the test in the first vertical direction, move 8cm horizontally from the last measuring point An in the first vertical direction to determine the position of the first measuring point B1 in the second vertical direction, and perform stress testing in the second vertical direction. Move upwards from measuring point B1 in the second vertical direction to select a measuring point, following the same principle as the measuring point selection in the vertical direction. After completing the test in the second vertical direction, move horizontally from the last measuring point Bn in the second vertical direction to select the measuring point in the third vertical direction. The position of the first measuring point C1 is determined by using the absolute value of stress change b between A1 and Bn as the control variable. If the absolute value of stress change b is greater than 1 MPa, the distance between measuring point C1 and measuring point Bn should be 8 cm. If the absolute value of stress change b is less than 1 MPa, 0.75 MPa, 0.5 MPa, 0.4 MPa, and 0.25 MPa respectively, the distance between measuring point C1 and measuring point Bn should be 20 mm, 10 mm, 7.5 mm, 5 mm, and 3 mm respectively. This process is repeated. When the absolute value of stress change is less than or equal to 0.2 MPa, the minimum measuring interval of 2 mm should be selected to ensure the accuracy of the instrument.

[0078] Interpolation was used to determine the values ​​between two adjacent measuring points, and a continuous and complete stress distribution diagram was drawn.

[0079] Specifically, an interpolation method was used to draw the stress distribution map. A subroutine for calculating the interpolation was written using MATLAB. Four interpolations were selected between every two measuring points to reduce the error between the calculated stress value and the actual value.

[0080] Specifically, the subroutine for calculating the interpolation is as follows:

[0081] n = input('Please enter the number of interpolations n=');

[0082] start_point=input('Please enter the starting point coordinates X1=');

[0083] finish_point=input('Please enter the coordinates of the final point X2=');

[0084] increments=input('Please enter the distance L between two adjacent measurement points=');

[0085] [rm]=size(C);

[0086] node=r*m;

[0087] if node ~= 2*(n+2)

[0088] error('The number of nodes is insufficient')

[0089] end

[0090] if n <= 0

[0091] error('Insufficient input parameters')

[0092] end

[0093] for j = 3:n+3

[0094] for i = j-1:n+2

[0095] C(i,j)=(C(i,j-1)-C(i-1,j-1)) / (C(i,1)-C(i+2-j,1));

[0096] end

[0097] end

[0098] for x = start_point:increments:finish_point

[0099] y = 0;

[0100] S = 1;

[0101] for i = 1:n+2

[0102] for j = i-1:-1:1

[0103] S = S*(x-C(j,1));

[0104] end

[0105] y = y+C(i,i+1)*S;

[0106] end

[0107] disp(['X: ',num2str(x)]);

[0108] disp(['Y: ',num2str(y)]);

[0109] K = 1;R = 1;

[0110] for i = 1:n+1

[0111] K = K*(x-C(i,1));

[0112] end

[0113] R=abs(C(n+2,n+3)*K)

[0114] end

[0115] The zero coordinate point is where the top surface of the prefabricated power transmission foundation intersects with the first vertical direction. The vertical direction is the Y coordinate, with the vertical downward direction being the positive Y coordinate direction. The horizontal direction is the X coordinate. During the X-direction measurement process, the movement is unidirectional, that is, the movement direction when selecting the measuring point in the horizontal direction, and the movement direction is the positive X coordinate direction.

[0116] Specifically, in step S5, after measuring the contact stress of the prefabricated power transmission foundation, the sensor 2 is promptly removed from the gap 6 of the contact surface of the assembly module to prevent the sensor 2 from being crushed and damaged. The measurement spacing when simulating the actual load is consistent with the measurement spacing when measuring the initial contact stress.

[0117] More specifically, all stresses mentioned in this article are contact stresses.

[0118] Although embodiments of the invention have been shown and described, those skilled in the art will be able to make various changes, modifications, substitutions and alterations to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for detecting contact stress in prefabricated power transmission foundations, characterized in that: The device includes a protective clip (1), a sensor (2), a steel bracket (3), and a slide rail (5). The bottom end of the steel bracket (3) is slidably mounted on the slide rail (5). The slide rail (5) is detachably mounted on the top surface of the prefabricated power transmission foundation. The protective clip (1) is suspended on the steel bracket (3) by a telescopic thin steel column (4). The sensor (2) is installed in the protective clip (1) and is connected to a data acquisition system. A method for detecting contact stress in prefabricated power transmission foundations includes the following steps: S1: Assemble the prefabricated power transmission foundation at the construction site and set the slide rail mounting holes on the prefabricated power transmission foundation. After the prefabricated power transmission foundation is assembled, fix the slide rail (5) of the detection device to the prefabricated power transmission foundation through the slide rail mounting holes. S2: Insert the sensor (2) of the detection device into the contact surface gap (6) between the assembled modules (7) of the prefabricated power transmission foundation. The sensor (2) moves in the vertical and horizontal directions through the slide rail (5) and the telescopic thin steel column (4). The mechanical sensor tests the contact stress value at each point of the contact surface in sequence, and takes the contact stress value at the first test point as the initial value. S3: Utilize LVDT displacement sensors to measure the vertical and horizontal displacement distances of the detection device, obtain the position of the detected point in real time, and determine the location of the maximum contact stress. S4: The LVDT displacement sensor and mechanical sensor transmit the detected data to the data acquisition system. The data acquisition system exports the contact stress values ​​and corresponding stress locations at the contact surfaces of each assembly module (7) in real time and draws a stress distribution diagram. S5: Apply load to the prefabricated power transmission foundation, repeat the operation steps of S2, and measure the change of contact stress value at the contact surface of each assembly module (7) after simulating the actual load. S6: Repeat steps S3 and S4 to obtain the stress distribution diagram and the location of the maximum contact stress after the load is applied.

2. The method for detecting contact stress in prefabricated power transmission foundations according to claim 1, characterized in that: The sensor (2) includes a mechanical sensor and an LVDT displacement sensor.

3. The method for detecting contact stress in prefabricated power transmission foundations according to claim 1, characterized in that: The protective clip (1) is made of two steel plates welded together.

4. The method for detecting contact stress in prefabricated power transmission foundations according to claim 1, characterized in that: In step S2, the contact stress value is tested by selecting measurement points. During the test, the top surface of the prefabricated power transmission foundation is used as a reference. The measurement point A1 is selected by moving 8cm downwards vertically. The contact stress value at measurement point A1 is measured. From measurement point A1, the measurement point A2 is selected by moving 8cm downwards vertically. The contact stress value at measurement point A2 is measured. The absolute value of the stress change 'a' between measurement points A1 and A2 is used as a control variable. The measurement point C is selected by moving downwards vertically. If the absolute value of the stress change 'a' is less than 1 MPa, then… When selecting measuring point A3, the distance between measuring point A3 and measuring point A2 is 5cm. If the absolute value of stress change a is greater than 1MPa, the distance between measuring point A3 and measuring point A2 is 8cm. Then, continue to move downwards along the same vertical direction to select measuring point A4. At this time, the absolute value of stress change between measuring point A3 and measuring point A4 is used as the control variable, and the distance between measuring point A4 and measuring point A3 is determined according to the above principle. In this way, measuring points are selected downwards in sequence, and the control variable is the absolute value of stress change between the two measuring points before the selected measuring point. Following the principle of selecting the measurement spacing between measuring points in the vertical direction, the same principle of controlling the absolute value of stress change between two measuring points is applied in the horizontal direction. After completing the first vertical direction test, the position of the last measuring point An in the first vertical direction is moved 8cm horizontally to determine the position of the first measuring point B1 in the second vertical direction. Stress testing is then performed in the second vertical direction. Measuring points are selected by moving upwards from measuring point B1 in the second vertical direction, following the same principle as in the vertical direction. After completing the second vertical direction test, the position of the last measuring point Bn in the second vertical direction is moved horizontally to select the third... The position of the first measuring point C1 in the vertical direction is determined. At this point, the absolute value of the stress change b between A1 and Bn is used as the control variable. If the absolute value of the stress change b is greater than 1MPa, the distance between measuring point C1 and measuring point Bn is 8cm when measuring point C1 is selected. If the absolute value of the stress change b is less than 1MPa, 0.75MPa, 0.5MPa, 0.4MPa, and 0.25MPa respectively, the distance between measuring point C1 and measuring point Bn is 20mm, 10mm, 7.5mm, 5mm, and 3mm respectively when measuring point C1 is selected. The test is carried out in this manner. When the absolute value of the stress change is less than or equal to 0.2MPa, the minimum measurement interval of 2mm is selected. Interpolation was used to determine the values ​​between two adjacent measuring points, and a continuous and complete stress distribution diagram was drawn.

5. The method for detecting contact stress in prefabricated power transmission foundations according to claim 1, characterized in that: Stress distribution diagrams were plotted using interpolation. A subroutine for calculating interpolation was written in MATLAB, with four interpolations performed between every two measurement points to reduce the error between the calculated and actual stress values.

6. The method for detecting contact stress in prefabricated power transmission foundations according to claim 5, characterized in that: The subroutine for calculating the interpolation is: n = input('Please enter the number of interpolations n='); start_point=input('Please enter the starting point coordinates X1='); finish_point=input('Please enter the coordinates of the final point X2='); increments=input('Please enter the distance L between two adjacent points='); [rm]=size(C); node=r*m; if node ~= 2*(n+2) error('Insufficient number of nodes') end if n<=0 error('Insufficient input parameters') end for j=3:n+3 for i=j-1:n+2 C(i,j)=(C(i,j-1)-C(i-1,j-1)) / (C(i,1)-C(i+2-j,1)); end end for x=start_point:increments:finish_point y=0; S=1; for i=1:n+2 for j=i-1:-1:1 S = S*(xC(j,1)); end y = y + C(i, i+1) * S; end disp(['X:',num2str(x)]); disp(['Y:',num2str(y)]); K=1; R=1; for i=1:n+1 K = K * (xC(i, 1)); end R=abs(C(n+2,n+3)*K) end The zero coordinate point is where the top surface of the prefabricated power transmission foundation intersects with the first vertical direction. The vertical direction is the Y coordinate, with the vertical downward direction being the positive Y coordinate direction and the horizontal direction being the X coordinate. During the X-direction measurement, the movement is unidirectional, and the direction of movement is the positive X coordinate direction.

7. The method for detecting contact stress in prefabricated power transmission foundations according to claim 1, characterized in that: In step S5, after measuring the contact stress of the prefabricated power transmission foundation, the sensor (2) is promptly removed from the gap (6) between the contact surfaces of the assembly modules to prevent the sensor (2) from being crushed. The measurement spacing when simulating the actual load is consistent with the measurement spacing when measuring the initial contact stress.

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