CN103335941B - A kind of analogue measurement device of steel tower galvanized steel plain sheet coefficient of static friction and measuring method - Google Patents

Abstract

The present invention relates to a kind of analogue measurement device of steel tower galvanized steel plain sheet coefficient of static friction, and use the method for this analogue measurement measurement device steel tower galvanized steel plain sheet coefficient of static friction; Be installed in cupping machine by analogue measurement device of the present invention, adopt pressure transducer to measure, this method can be implemented in the lab, easy to operate, and the result of mensuration is accurate, has directive significance to steel tower one-piece construction and stability assessment.

Description

An analog measurement device and measurement method for static friction coefficient of galvanized steel plate of iron tower

technical field

The invention relates to an analog measuring device for the static friction coefficient of the galvanized steel plate of an iron tower, and a method for measuring the static friction coefficient of the iron tower galvanized steel plate by using the analog measuring device.

Background technique

The iron tower connects the main material to the main material, and the main material to the inclined material through bolts. The connection point is called a node. When the main material is connected to the main material, the upper and lower main materials are connected together through the gusset plate. The force transmission of the main material is transmitted through the shear force of the bolt and the friction force of the contact surface of the tower material pressed by the bolt pre-tightening force. When the bolt pre-tightening force is large enough, the force transmission mode between the tower materials should be dominated by friction; when the interaction force between the tower materials is greater than its maximum static friction force, the tower materials will slip, and the force transmission mode between the tower materials It will be changed into the shear transmission force of the bolt, which will affect the service life of the bolt. Therefore, in the actual use of the iron tower, the way of node force transmission is crucial to the overall structure and stability of the iron tower. When designing the iron tower, it is necessary to evaluate the static friction coefficient of the iron tower steel plate.

At present, there are usually two methods for measuring the coefficient of friction: 1) Apply pressure by a heavy object to measure the static friction force at which the object begins to move relative to each other, and obtain the static friction coefficient; Motion, at this time the tangent function of the slope angle is the static friction coefficient. However, the pressure per unit area of these two methods cannot be increased infinitely due to the limitation of the weight of the weight. However, the coefficient of static friction is different under the pressure exerted by gravity under high contact pressure. At present, there is no method to simulate the actual working conditions of iron tower angle steel to measure the static friction coefficient of iron tower galvanized steel plate under high contact pressure.

If the two surfaces are at rest, the contact between the two surfaces will form a strong bonding force - static friction, unless the bonding force is destroyed, one surface can move against the other surface, and the force that breaks the bonding force makes it move instantaneously The ratio of the vertical force on one surface is called the coefficient of static friction μs, and the relationship is as follows:

f =μs·P

μs - coefficient of static friction;

f - friction force, unit Newton (N);

P——the vertical force on the surface, in Newton (N).

And this destructive force is also the maximum force to make the object start, and we call this force the maximum static friction force.

Contents of the invention

The main technical problem to be solved by the present invention is to provide an analog measurement device and measurement method for the static friction coefficient of iron tower galvanized steel plate under high contact pressure under high contact pressure, which can be operated in a laboratory and can be operated in a laboratory, with accurate results and strong repeatability.

The present invention adopts following technical scheme:

The analog measuring device of the present invention is composed of an upper galvanized steel sheet, a middle galvanized steel sheet, a lower galvanized steel sheet, a sleeve and a pressure sensor; Bolt holes with equal diameters are respectively provided with bolt holes equal in diameter to the bolt holes at the upper and lower ends of the middle galvanized steel sheet; connected by first bolts and first nuts; the lower end of the middle galvanized steel sheet and the lower galvanized steel sheet are connected by second bolts and second nuts.

Further, in the analog measurement device of the present invention, a first washer is sleeved on the first bolt between the middle galvanized steel plate and the first nut, and a first washer is sleeved on the second bolt between the middle galvanized steel plate and the second nut. There is a second gasket.

Further, the width of the upper, middle and lower galvanized steel sheets in the analog measuring device of the present invention is 120mm, the thickness is 10mm, and the diameter of each bolt hole is 21.5mm.

Further, the specifications of the bolts, nuts and washers in the analog measuring device of the present invention are M20 and galvanized.

Measurement method of the present invention comprises the following steps:

Step 1: Clamp the upper end of the upper galvanized steel sheet and the lower end of the lower galvanized steel sheet in the upper and lower clamps of the tensile testing machine respectively, and connect the output cable of the pressure sensor to the corresponding cable of the tensile testing machine. connected to the input;

Step 2: Make the upper and lower galvanized steel sheets in the center of the upper and lower clamps, and the upper and lower clamps are in a clamped state; the first and second bolts are in a loose state; use a torque wrench to completely lock the second bolt Dead, that is, the middle and lower galvanized steel sheets do not slide in the natural state; then a tensile force of 80~100KN is applied to the simulated measuring device through a tensile testing machine to eliminate the relative sliding of the middle and lower galvanized steel sheets in the follow-up test ;

Step 3: Adjust the first bolt so that the bolt holes of the upper galvanized steel sheet and the middle galvanized steel sheet are staggered by 0.5~2mm; apply a tightening torque of 0~380N·m to the first bolt, and display the preload at this time through the pressure sensor force P ₀ ;

Step 4: Use a tensile testing machine to load the simulated measuring device with a loading speed of 0.1mm/min~1mm/min, and record the force F loaded when the displacement increases during the test through the testing machine software in the tensile testing machine ; When the sliding between the upper galvanized steel plate and the middle galvanized steel plate is hindered by the upper galvanized bolt, stop the test;

Step 5: draw force-displacement curve according to the data obtained in step 4, the force value corresponding to the first platform in the curve is the friction force f between the upper galvanized steel plate and the middle galvanized steel plate;

Step 6: Calculate the static friction coefficient μs between the upper galvanized steel plate and the middle galvanized steel plate according to the formula (1), the pretightening force P ₀ obtained in step 3 and the friction force f obtained in step 5;

μs = f /P ₀ (1)

μs - coefficient of static friction;

f - the friction force of the upper and middle galvanized steel sheets, unit N;

P ₀ ——The pretightening force of the first bolt, unit N.

Further, the measurement method of the present invention calibrates the pressure sensor before starting step three, applies a force P ₀ of 0 to 180KN to the pressure sensor through the tensile testing machine clamp, and records different forces through the software of the tensile testing machine The voltage U of the pressure sensor, according to the obtained force and voltage data, draw the force-voltage curve, and obtain the force-voltage relationship (2) according to the curve;

U= k F+b(2)

U——the voltage displayed by the pressure sensor, in V;

F——the force exerted by the tensile testing machine, in N;

k —coefficient, unit V/N;

b——the initial voltage displayed by the pressure sensor when the force is 0, in V.

Further, the force applied by the tensile testing machine in the measurement method of the present invention is tension or compression.

Further, in step 7 of the measuring method of the present invention, the tensile testing machine loads force on the analog measuring device at a loading speed of 0.5mm/min.

The connection of galvanized steel sheets, bolts and nuts in the measuring device of the present invention simulates the connection mode of iron tower galvanized steel sheets under actual working conditions.

The main function of the sleeve of the invention is to transmit the bolt pretightening force to the sensor, and to connect the galvanized bolt and the pressure sensor.

The tensile testing machine of the present invention can apply pressure or tension to the upper galvanized steel plate and the lower galvanized steel plate, and the testing machine software equipped with it can record the test process in the whole process, which is convenient for analyzing the change of the actual force transmission mode of the steel plate and the difference between the steel plates. Create sliding friction.

Beneficial effects of the present invention:

The method of the invention provides a method for measuring the static friction coefficient of the iron tower galvanized steel plate in a laboratory that can simulate actual working conditions, and can conveniently determine the force transmission mode of the iron tower nodes and evaluate its service life.

The method of the invention has strong reproducibility, and multiple experiments can be repeated, and the experimental results of different experiments are linearly fitted to obtain the experimental values, thereby further improving the accuracy of the data.

Description of drawings

Accompanying drawing 1 is the structural representation of embodiment 1 of the present invention;

Accompanying drawing 2 is the left view of embodiment 1 of the present invention;

Accompanying drawing 3 is the force-voltage calibration curve drawn in step 3 of embodiment 3 of the present invention;

Accompanying drawing 4-1 is the tension-displacement curve that the first test of embodiment 3 draws;

Accompanying drawing 4-2 is the tension-displacement curve that the second test of embodiment 3 draws;

Accompanying drawing 4-3 is the tension-displacement curve that the third test of embodiment 3 draws;

Accompanying drawing 4-4 is the tension-displacement curve that the 4th test of embodiment 3 draws;

Accompanying drawing 5 is the normalized model curve of the tension-displacement relationship that embodiment 3 draws;

Accompanying drawing 6-1 is the frictional force-preload relationship figure of the first test of embodiment 3;

Accompanying drawing 6-2 is the frictional force-preload relationship figure of the second test of embodiment 3;

Accompanying drawing 6-3 is the friction force-pretightening force relationship diagram of the third test of embodiment 3;

Accompanying drawing 6-4 is the frictional force-preload relation figure of the 4th test of embodiment 3;

In the attached drawings, 1 upper galvanized steel plate, 2 middle galvanized steel plate, 3 lower galvanized steel plate, 4 first bolt, 5 first nut, 6 sleeve, 7 pressure sensor, 8 first washer, 9 second bolt , 10 second nuts, 11 second washers.

detailed description

Example 1

As accompanying drawing 1,2, analog measuring device of the present invention is made up of upper galvanized steel plate 1, middle galvanized steel plate 2, lower galvanized steel plate 3, sleeve 6 and pressure sensor 7; The lower end and the upper end of the lower galvanized steel sheet 3 are respectively provided with bolt holes equal in diameter, and the upper and lower ends of the middle galvanized dry plate 2 are respectively provided with bolt holes equal in diameter to the bolt holes; the sleeve 6. The pressure sensor 7, the upper end of the upper galvanized steel sheet 1 and the middle galvanized steel sheet 2 are connected sequentially through the first bolt 4 and the first nut 5; the lower end of the middle galvanized steel sheet 2 and the lower galvanized steel sheet 3 pass through the second The bolt 9 is connected with the second nut 10 . A first washer 8 is set on the first bolt 4 between the middle galvanized steel plate 2 and the first nut 5, and a second washer 8 is set on the second bolt 9 between the middle galvanized steel plate 2 and the second nut 5. There is a second washer 11, the first washer 8 and the second washer 11 are used to protect the steel plate and further simulate the actual working conditions. The width of the upper galvanized steel plate 1, the middle galvanized steel plate 2 and the lower galvanized steel plate 3 of the analog measurement device is 120 mm, the thickness is 10 mm, and the diameter of each bolt hole is 21.5 mm.

Example 2

The difference between embodiment 2 and embodiment 1 is only that no washer is provided between the steel plate and the nut. Since the test can be stopped when the sliding between the upper galvanized steel plate 1 and the middle galvanized steel plate 2 is blocked, it is not necessary to remove the washer. affect the accuracy of test data.

Example 3

Use the simulation measuring device of embodiment 1 to carry out the measurement of static friction coefficient of galvanized steel plate of iron tower under high contact pressure.

Step 1: Clamp the upper end of the upper galvanized steel sheet 1 and the lower end of the lower galvanized steel sheet 3 into the upper and lower clamps of the tensile testing machine respectively, connect the output cable of the pressure sensor 7 to the tensile tester The corresponding input terminal of the machine is connected. The upper galvanized steel sheet 1, the middle galvanized steel sheet 2 and the lower galvanized steel sheet 3 of this embodiment are all galvanized steel sheets with a width of 120mm and a thickness of 10mm, and the diameter of the opening is Ф21.5mm. The punching process is adopted, and the hole is first opened and then plated zinc. The specifications of the first bolt 4 , the first nut 5 , the first washer 8 , the second bolt 9 , the second nut 10 and the second washer 11 in this embodiment are M20, galvanized, and multiple sets. The sensor 7 of this embodiment is a BSQ-2 sensor with a measuring range of 200 kN, and is calibrated using a CMT5205 tensile testing machine.

Step 2: Make the upper galvanized steel plate 1 and the lower galvanized steel plate 3 in the center of the upper and lower clamps, the upper and lower clamps are in a clamped state; the first and second bolts are in a loose state. Use a torque wrench to completely lock the second bolt 9, that is, the middle galvanized steel plate 2 and the lower galvanized steel plate 3 do not slide under the test state; the torque wrench used is TLB500N·m, and the second bolt 9 is 6.8 grade For bolts, the maximum tightening torque of 6.8-grade bolts is 362.21 N·m, and the torque applied by the torque wrench to the second bolt 9 exceeds 400 N·m, so that the second bolt 9 is completely locked. Then use a tensile testing machine to apply a tensile force of 80 to 100 kN to the analog measuring device to eliminate the relative sliding between the middle galvanized steel sheet 2 and the lower galvanized steel sheet 3 .

Step 3: In this embodiment, a CMT5205 tensile testing machine is used for calibration, and a force P ₀ of 0-180KN is applied to the pressure sensor through the clamp of the tensile testing machine, and the pressure is increased by 10kN each time, and the sensor voltage is recorded once. For the calibration results, see Table 1. Since the maximum tensile force used in the follow-up test steps of this embodiment is 70KN, when drawing the curve, the pressure range of 0~70KN is used for calibration, and the drawn pressure-voltage curve is shown in Figure 3, according to the formula (2) Get the pressure-voltage relationship.

U= k F+b(2)

U——the voltage displayed by the pressure sensor, in V;

F——the force exerted by the tensile testing machine, in N;

k —coefficient, unit V/N;

b——the initial voltage displayed by the pressure sensor when the force is 0, in V.

The pressure-voltage relationship in this embodiment is: U=0.028P ₀ +0.0254.

Table 1 The pressure and sensor voltage detected during the calibration of the tensile testing machine

Step 4: Adjust the upper galvanized bolt 4 so that the upper galvanized steel plate 1 is displaced downward by 2 mm, so that the bolt holes of the upper galvanized steel plate 1 and the middle galvanized steel plate 2 are staggered by 2 mm, and the displacement does not affect the first bolt 4 installation, and make the upper galvanized steel plate 1 obtain the maximum slippage. A torque wrench is used to apply a tightening torque Mt not exceeding 380 N·m to the first bolt 4 , and the pre-tightening force P ₀ is displayed by the pressure sensor 7 .

Four experiments were carried out in this embodiment, and each experiment was repeated several times. Table ₂ shows the preload P0 obtained from each repeated calculation. The bolts and nuts used in each embodiment are different, resulting in different bolt pretightening forces.

Step 5: Use a CMT5205 tensile testing machine to load the simulated measuring device with a loading speed of 0.5 mm/min, which is the closest to the stress state of the tower material in actual use. The force F loaded when the displacement increases during the test is recorded by the testing machine software in the tensile testing machine.

Draw the tension-displacement curve, as shown in curve 1 of attached drawing 4-1. In the elastic deformation stage of the steel plate, when the force gradually increases, the upper galvanized steel plate 1 and the middle galvanized steel plate 2 slide. From each curve, there is an obvious and slowly rising plateau period, and the displacement increases. But the force doesn't change much. Each curve has three plateaus, which gradually rise; from the video analysis recorded during the test, the three plateaus are caused by relative sliding between different surfaces. The first platform stage is the relative sliding between the upper galvanized steel plate 1 and the middle galvanized steel plate 2; when the force continues to increase, the contact surface between the middle galvanized steel plate 2 and the first washer 8 also starts to slide, and the first Two plateaus; after the force continued to increase, the contact surface between the upper galvanized steel plate 1 and the sleeve 6 began to slide, and a third plateau occurred. Finally, because the first bolt 4 limited the upper galvanized steel plate 1 Sliding, under the action of shear force, the upper galvanized steel plate 1 bears tension and continues to elastically deform. According to the tension-displacement curve relationship of the test, the factors of sliding of the upper galvanized steel sheet 1 can be normalized. Figure 5 is the normalized model curve of the tension-displacement relationship, where the step ① represents the friction between the upper galvanized steel plate 1 and the middle galvanized steel plate 2, and the step ② represents the friction between the middle galvanized steel plate 2 and the first washer 8 The step ③ indicates the friction between the upper galvanized steel plate 1 and the sleeve 6, and the steep slope ④ indicates that the sliding of the steel plate is restricted by the first bolt 4, and the upper galvanized steel plate 1 and the middle plated The zinc steel plate 2 bears the tensile force when the tensile force continues to deform elastically.

Therefore, the force corresponding to the first plateau period in the tension-displacement curve is the force between the upper galvanized steel plate 1 and the middle galvanized steel plate 2 to overcome friction and generate relative sliding, that is, the friction force between the steel plates to be studied , so the friction force f between the steel plates should be the force value corresponding to the first plateau period in the curve, and the black dot in Figure 4-1 is the position of the friction force f .

When the tensile force exceeds the maximum static friction force between the steel plates, the upper galvanized steel plate 1 will slide relative to the middle galvanized steel plate 2 under the action of tension, and the theoretical maximum static friction force is a fixed value, so the force value does not increase during the sliding process of the steel plates. Displacement changes; when the sliding between the steel plates is hindered by the bolts, the increase in tension will cause sliding between the middle galvanized steel plate 2 and the first washer 8, and the test can be stopped at this time.

Loosen the first bolt 4, clear the displacement, retighten the first bolt 4, increase the tightening torque to the first bolt 4, repeat the above steps, measure the friction force between the steel plates several times, draw the tension-displacement curve, and obtain the graph For the 2nd to 5th curves in 4-1, complete the first test process. Replace the first bolt 4, repeat the above test steps 5 times, and get 5 curves of the second test in Figure 4-2; Figure 4-3 shows 8 curves of the third test. According to the above test, when the sliding between the upper galvanized steel plate 1 and the middle galvanized steel plate 2 is hindered by the upper galvanized bolt 4, after the upper galvanized steel plate 1 and the middle galvanized steel plate 2 are transformed into shear transmission force, the tensile force It will gradually increase, and at this time, the loading can be stopped and the test is ended. Therefore, in the fourth test, the test was stopped when the sliding between the upper galvanized steel plate 1 and the middle galvanized steel plate 2 was blocked, and 6 curves as shown in Figure 4-4 were obtained. The friction force f measured in the four tests is shown in Table 2.

Table 2 shows the bolt pretightening force P0 and the friction force f between steel plates under different tightening torques. Figures 6-1, 6-2, 6-3, and 6-4 are the pretightening forces of the four tests respectively— The friction relationship diagram, the first bolt 4 used in each test is different, and the linear fitting is carried out according to the formula (1), and the static friction coefficient μs between the steel plates in the 4 groups of tests is obtained.

μs = f /P ₀ (1)

μs - coefficient of static friction;

f - the frictional force between the upper galvanized steel plate 1 and the middle galvanized steel plate 2, unit N;

P ₀ ——the pretightening force of the first bolt 4, unit N.

Table 2 Test results of friction coefficient μs between steel plates

Through the linear fitting of the friction force f and the pre-tightening force P ₀ , the obtained friction coefficient μs=0.71～0.77. The data show that the static friction coefficient of dry friction between zinc and zinc is 0.6, and the data measured by the test is higher than the theoretical value. When the preload is small, the measured static friction coefficient is less than 0.6, and the minimum is 0.44. It can be seen from Figure 6 that as the number of tests increases, the dispersion of the friction coefficient gradually decreases. The deviation between the test value and the theoretical value is analyzed as follows:

1) Theoretically, the friction coefficient is a constant determined by the contact surface, and has nothing to do with the contact area and pressure. And any plane is not an absolute plane, it is a rough surface under the microscope, so the contact between two planes is point contact, not surface contact. When the pre-tightening force is small, the contact force between the steel plates is small, and the surfaces of the two steel plates only contact at the contact points, and the total contact area of these contact points only accounts for a very small part of the total surface area defined by the contact contour. As the pressure increases, the surface metal between the steel plates begins to deform and grind flat, the diameter of each contact point increases, and the number of contact points increases, which increases the contact area and the friction coefficient. Therefore, the measured friction coefficient is lower than the theoretical value when the preload is small.

2) With the increase of the pre-tightening force, the pre-tightening force exceeding 1 ton is pressed on the plane of 120mm×120mm and applied through the bolt; due to the uneven force on the contact surface, the position close to the bolt hole, the pressure per unit area If this pressure is exceeded, the coefficient of friction is measured at high contact pressure. The contact between solids has elastic-plastic characteristics, and when the pressure is small, the contact points rely on the elastic deformation of the convex part to contact each other. Under high contact pressure, the contact area between steel plates increases significantly, and the contact between molecules is not only the attraction between molecules and elastic deformation; due to the increase in pressure, the concave and convex points on the contact surface are completely occluded, and the surface metal Sliding changes from overcoming the intermolecular attraction to destroying the intermolecular bonding force of the surface metal, from elastic deformation to plastic deformation, the concave and convex points between the steel plates are smoothed, the contact between the steel plates is closer, and the contact area is further increased. make the friction force further increase. And because the surface of the steel plate is galvanized material, the hardness is relatively soft, and the zinc layer is more easily deformed under high contact pressure. After the test, it was found that the zinc layer at the joint part of the steel plate deformed and fell off, and there were obvious sliding marks; The dry friction between zinc and zinc will increase the friction coefficient, which is consistent with the test results. Therefore, the experimental value measured by the method of the present invention is more accurate than the theoretical value. The present invention is a method for measuring the static friction coefficient of iron tower galvanized steel plates in a laboratory simulating actual working conditions. The present invention can conveniently measure the static friction coefficients between iron tower galvanized steel plates in different periods, further determine the force transmission mode of iron tower steel plate nodes, and evaluate its service life.

3) Every time one more test is done, the discreteness of the friction coefficient decreases. The reason is that as the number of tests increases, a large amount of wear and flattening occurs on the surface of the steel plate, and the contact area between the steel plates decreases after multiple tests. Therefore, In the repeated test in the later period, even a small preload force produced a large friction force, because the contact area did not change much and the friction coefficient tended to be stable.

Claims (5)

1. a method for measuring the static friction coefficient of iron tower galvanized steel plate utilizing analog measuring device, it is characterized in that described analog measuring device is made of upper galvanized steel plate (1), middle galvanized steel plate (2), lower galvanized steel plate (3 ), a sleeve (6) and a pressure sensor (7); Bolt holes with equal diameters are respectively arranged on the lower end of the upper galvanized steel sheet (1) and the upper end of the lower galvanized steel sheet (3). The upper and lower ends of the galvanized steel sheet (2) are respectively provided with bolt holes equal in diameter to the bolt holes; the sleeve (6), the pressure sensor (7), the upper galvanized steel sheet (1) and the middle galvanized The upper end of the steel plate (2) is sequentially connected by the first bolt (4) and the first nut (5); the lower end of the middle galvanized steel sheet (2) and the lower galvanized steel sheet (3) are connected by the second bolt (9) and The second nut (10) is connected; Described measuring method comprises the following steps: Step 1: Clamp the upper end of the upper galvanized steel sheet (1) and the lower end of the lower galvanized steel sheet (3) respectively in the upper and lower clamps of the tensile testing machine, and place the pressure sensor (7) The output cables are connected to the corresponding input terminals of the tensile testing machine; Step 2: Make the upper and lower galvanized steel sheets (1, 3) in the center of the upper and lower clamps, and the upper and lower clamps are in a clamped state; the first and second bolts are in a loose state; use a torque wrench to make The second bolt (9) is completely locked, that is, the middle and lower galvanized steel sheets (2, 3) do not slide in the natural state; Eliminate the relative sliding of the middle and lower galvanized steel sheets (2, 3) in subsequent tests; Step 3: Adjust the first bolt (4) so that the bolt holes of the upper galvanized steel sheet (1) and the middle galvanized steel sheet (2) are staggered by 0.5-2mm; apply 0-380N m to the first bolt (4). Tightening torque, the pre-tightening force P ₀ at this time is displayed by the pressure sensor (7); Step 4: Use a tensile testing machine to load the simulated measuring device with a loading speed of 0.1 mm/min to 1 mm/min, and record the force F loaded when the displacement increases during the test through the testing machine software in the tensile testing machine ; When the sliding between the upper galvanized steel plate (1) and the middle galvanized steel plate (2) is hindered by the first bolt (4), stop the test; Step 5: Draw a force-displacement curve according to the data obtained in step 4. The force value corresponding to the first platform in the curve is the friction force f between the upper galvanized steel plate (1) and the middle galvanized steel plate (2); Step 6: Calculate the coefficient of static friction μs between the upper galvanized steel sheet (1) and the middle galvanized steel sheet (2) according to the formula (1), the pretightening force P0 obtained in step 3, and the friction force _f obtained in step 5; μs=f/P ₀ (1) μs - coefficient of static friction; f - the friction force of the upper and middle galvanized steel sheets (1, 2), unit N; P ₀ ——The pretightening force of the first bolt (4), unit N. 2. a kind of measuring method utilizing analog measuring device to carry out iron tower galvanized steel plate static friction coefficient according to claim 1, it is characterized in that between the middle galvanized steel plate (2) of described analog measuring device and the first nut (5) The first washer (8) is sleeved on the first bolt (4) between the two, and the second washer is sleeved on the second bolt (9) between the middle galvanized steel plate (2) and the second nut (5). (11); the width of the upper, middle and lower galvanized steel sheets (1, 2 and 3) is 120mm, the thickness is 10mm, and the diameter of each bolt hole is 21.5mm; each bolt, each nut and each The size of the gasket is M20, galvanized. 3. a kind of measuring method utilizing analog measurement device to carry out iron tower galvanized steel plate static friction coefficient according to claim 1, it is characterized in that before starting step 3, demarcate pressure sensor, press clamp by tensile testing machine to described pressure sensor Apply a force P ₀ of 0 to 180KN, and record the voltage U of the pressure sensor (7) under different forces through the software of the tensile testing machine, draw a force-voltage curve according to the obtained force and voltage data, and obtain Force-voltage relationship (2); U=kF+b(2) U——the voltage displayed by the pressure sensor, in V; F——the force exerted by the tensile testing machine, in N; k—coefficient, unit V/N; b——the initial voltage displayed by the pressure sensor when the force is 0, in V. 4. a kind of measuring method utilizing analog measuring device to carry out the static friction coefficient of iron tower galvanized steel plate according to claim 3, is characterized in that the force that described tensile testing machine applies is pulling force or pressure. 5. a kind of measuring method utilizing analog measuring device to carry out iron tower galvanized steel plate static friction coefficient according to claim 4, is characterized in that in step 4, tensile testing machine is to described analog measuring device with the loading speed of 0.5mm/min loading force.