Test method for prestressing efficiency of corrugated steel web bridge

Abstract

The present invention provides a testing method for the prestressing efficiency of a corrugated steel web bridge. In this testing method, a plurality of strain gauges are attached to the bottom concrete slab, the top concrete slab and the outside of the corrugated steel web of the corrugated steel web bridge at intervals. All strain gauges are connected to a strain tester. The strain value measured before and after the prestressing tendons on the corrugated steel web bridge are tensioned by each strain gauge are collected by the strain tester. The strain tester is wirelessly connected to a control terminal, which transmits the collected strain value to the control terminal. The control terminal calculates the prestressing efficiency of the corrugated steel web bridge according to the received strain value. This testing method can realize a quick and easy calculation of the actual prestressing size shared by the top and bottom concrete slabs and the corrugated steel web, thereby quickly obtaining the prestressing efficiency of the corrugated steel web bridge, and then it is convenient to control the force applied when tensioning the prestressing tendons and ensure the prestress stored in the concrete slab.

Description

Technical Field

[0001] The invention relates to the technical field of corrugated steel web bridges, and in particular to a method for testing the prestressing efficiency of a corrugated steel web bridge and a method for constructing a corrugated steel web bridge. Background Art

[0002] Corrugated steel web bridges are bridges with concrete slabs for the top and bottom plates and corrugated steel webs for the webs. They are widely used in bridges with spans greater than 50m because they can reduce the deadweight of the beam and increase the span of the bridge. Among them, the corrugated steel web has a "wrinkle effect". In the design stage, the axial compressive rigidity of the corrugated steel web is assumed to be 0 and is not subject to any axial pressure. When axial prestress is applied, the web does not share the prestress, so that all the applied prestress can be received and stored by the top and bottom concrete slabs. However, the actual situation is that the web still shares part of the axial prestress. When the axial prestress sharing ratio reaches a certain level, it will cause insufficient prestress reserve in the top and bottom plates, resulting in cracks in the operation stage, which seriously affects the durability of the structure. To solve the above problems, the existing document "Research on the Efficiency of Prestressing Introduction of Composite Beams with Internal Prestressed Corrugated Steel Webs" proposes an introduction method, which introduces prestressing into the top and bottom concrete slabs to the greatest extent by setting up a steel-clad concrete component, and calculates the introduction efficiency. However, the calculation of the introduction efficiency of this method is complicated, and it is not easy to quickly calculate the size of the axial prestress shared by each part. This is a situation that people in this technical field do not want to see again and hope to improve. Therefore, it is very necessary to propose a method for quickly and easily calculating the actual size of the prestressing shared by the top and bottom concrete slabs, that is, a method for testing the efficiency of prestressing of corrugated steel web bridges. Summary of the invention

[0003] In view of the above, it is necessary to provide a test method for the prestressing efficiency of corrugated steel web bridges. This test method can quickly and easily calculate the actual prestress shared by the top and bottom concrete slabs and the corrugated steel webs, thereby quickly obtaining the prestressing efficiency of the corrugated steel web bridges, thereby facilitating the control of the force applied when tensioning the prestressed tendons and ensuring the prestress stored in the concrete slabs, solving the problem that in actual situations the web still shares a small part of the axial prestress, which may cause the top and bottom concrete slabs to receive insufficient stored prestress and crack.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] The test method of the prestressing efficiency of the corrugated steel web bridge is as follows: a plurality of strain gauges are attached to the bottom concrete slab, the top concrete slab and the outside of the corrugated steel web of the corrugated steel web bridge at intervals, and all the strain gauges are connected to the strain tester. The strain value measured before the prestressing tendons on the corrugated steel web bridge are tensioned and the strain value measured after the prestressing tendons on the corrugated steel web bridge are tensioned are collected by the strain tester. The strain tester is wirelessly connected to the control terminal, and the collected strain value is transmitted to the control terminal. The control terminal calculates the prestressing efficiency of the corrugated steel web bridge according to the received strain value. The calculation method is as follows:

[0006] S1. Establish a rectangular coordinate system to obtain the rectangular coordinate values ​​corresponding to the positions of each strain gauge, where the rectangular coordinate system corresponding to each strain gauge on the bottom concrete plate is (x 1i ,y 1i ), the rectangular coordinate system corresponding to each strain gauge on the corrugated steel web is (x 2j ,y 2j ), the rectangular coordinate system corresponding to each strain gauge on the top concrete plate is (x 3k ,y 3k ), i = 1, 2, 3, ... n, j = 1, 2, 3, ... m, k = 1, 2, 3, ... u, n is the number of strain gauges on the bottom concrete plate, m is the number of strain gauges on the corrugated steel web, and u is the number of strain gauges on the top concrete plate;

[0007] S2. The strain difference corresponding to each strain gauge is obtained according to the strain value measured before and after the prestressed tendons are tensioned by the strain gauge. The strain difference before and after the prestressed tendons are tensioned by each strain gauge on the bottom concrete slab is ε 1i , the strain difference of each strain gauge on the corrugated steel web before and after the prestressed tendons are tensioned is ε 2j , the strain difference before and after the prestressed tendons are tensioned on each strain gauge on the top concrete slab is ε 3k ;

[0008] S3. According to the rectangular coordinate system obtained in step S1 and the strain difference obtained in step S2, the fitting functions corresponding to the bottom concrete slab, the corrugated steel web and the top concrete slab are obtained, wherein the fitting function corresponding to the bottom concrete slab is ε1(x1, y1), the fitting function corresponding to the corrugated steel web is ε2(x2, y2); the fitting function corresponding to the top concrete slab is ε3(x3, y3);

[0009] S4, according to the fitting functions obtained in step S3, the axial prestress F1 of the bottom concrete slab, the axial prestress F3 of the top concrete slab, the axial prestress F2 of the corrugated steel web and the prestressing efficiency η of the corrugated steel web bridge are calculated, wherein,

[0010] 1) The calculation formula for the axial prestress F1 of the bottom concrete slab is:

[0011]

[0012] Where, E1 is the elastic modulus of the bottom concrete slab; A1 is the area of ​​the bottom concrete slab;

[0013] 2) The calculation formula for the axial prestress F3 of the top concrete slab is:

[0014]

[0015] Where, E3 is the elastic modulus of the top concrete slab; A3 is the area of ​​the top concrete slab;

[0016] 3) The calculation formula for the axial prestress F2 of the corrugated steel web is:

[0017]

[0018] Where, E2 is the elastic modulus of the corrugated steel web; A2 is the area of ​​the corrugated steel web;

[0019] 4) The calculation formula for the prestressing efficiency η of the corrugated steel web bridge is:

[0020]

[0021] Furthermore, at least two rows of strain gauges are arranged on the bottom concrete plate, each row of strain gauges is at the same height, and each row of strain gauges is provided with at least three strain gauges, and the spacing between two adjacent strain gauges in the same row is the same.

[0022] Furthermore, at least two rows of strain gauges are arranged on the top concrete slab, each row of strain gauges is at the same height, and each row of strain gauges is provided with at least three strain gauges, and the spacing between two adjacent strain gauges in the same row is the same.

[0023] Furthermore, all the strain gauges on the corrugated steel web are arranged in sequence along the connecting line direction of the top concrete plate and the bottom concrete plate, the spacing between two adjacent strain gauges is the same, and strain gauges are arranged at the junction of the corrugated steel web and the bottom concrete plate, and strain gauges are also arranged at the junction of the corrugated steel web and the top concrete plate.

[0024] Furthermore, the fitting function obtained in step S3 is obtained by using the Lagrange interpolation method.

[0025] In addition, the present invention also provides a corrugated steel web bridge construction method, which comprises the following steps:

[0026] S1. Build bridge piers. After the bridge piers are built, cast a section of main beam symmetrically along both sides of the bridge piers;

[0027] S2. After a section of main beam is cast, a strain gauge is arranged on the section of the main beam according to the above-mentioned test method for the prestressing efficiency of the corrugated steel web bridge, and the strain gauge is connected to the strain tester, and the strain tester is connected to the control terminal, and the strain gauge, strain tester and control terminal are debugged;

[0028] S3, tensioning prestressed tendons, the control terminal calculates the axial prestress F1 of the bottom concrete slab, the axial prestress F3 of the top concrete slab, the axial prestress F2 of the corrugated steel web and the prestressing efficiency η of the corrugated steel web bridge according to the calculation method in the test method of the prestressing efficiency of the corrugated steel web bridge, and the control terminal determines the axial prestress F1 of the bottom concrete slab and the axial prestress F3 of the top concrete slab according to the calculation results to determine whether the prestress of the concrete slab meets the requirements. When the judgment result shows that the prestress of the concrete slab does not meet the requirements, the control terminal obtains the increased prestress value according to the insufficient prestress value and the calculated application efficiency, and then controls the tensioning force of the tensioned prestressed tendons according to the obtained increased prestress value until the prestress of the concrete slab meets the requirements;

[0029] S4. Remove all strain gauges, cast another section of main beam, and repeat steps S2-S3 until all main beams are cast. When repeating step S3, the tensioning force of the prestressed tendons is determined by the control terminal based on the prestressing efficiency of the previous section of the main beam and the prestress required to be stored in the concrete slab.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The present invention discloses a method for testing the efficiency of prestressing of a corrugated steel web bridge, which can realize rapid and simple calculation of the actual axial prestressing of the top and bottom concrete slabs and the corrugated steel web, so as to quickly obtain the efficiency of prestressing of the corrugated steel web bridge; the calculated value verifies whether the prestress stored in the concrete slab is sufficient to ensure that the concrete slab does not crack, and at the same time clarifies the proportion of the axial prestress actually shared by the top and bottom concrete slabs, thereby solving the problem that in actual situations the web still shares a small part of the axial prestress, which may cause the top and bottom concrete slabs to receive insufficient stored prestress and crack, and provides a reference value for the subsequent specific value of prestressing, which is convenient for controlling the tensioning force when the prestressing tendons are subsequently tensioned.

[0032] 2. The present invention can be applied to corrugated steel web bridges, and has simple calculation and convenient operation, and has high promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is the arrangement position of the strain gauges of the top and bottom concrete slabs and the corrugated steel web of the present invention;

[0034] Figure 2 It is the rectangular coordinate system corresponding to the top and bottom concrete slabs and the corrugated steel web of the present invention.

[0035] Main component symbols

[0036] In the figure: bottom concrete slab 1, top concrete slab 2, corrugated steel web 3, strain gauge 4.

[0037] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0038] See also Figure 1 In a preferred embodiment of the present invention, a method for testing the efficiency of prestressing of a corrugated steel web bridge is provided. A plurality of strain gauges 4 are attached to the outside of a bottom concrete slab 1, a top concrete slab 2 and a corrugated steel web 3 of the corrugated steel web bridge at intervals. The strain gauges 4 are used to measure the strain magnitude before and after the prestressing tendons are tensioned at different positions. Preferably, at least two rows of strain gauges 4 are arranged on the bottom concrete slab 1. Each row of strain gauges 4 is at the same height. At least three strain gauges 4 are arranged in each row of strain gauges 4. The spacing between two adjacent strain gauges 4 in the same row is the same, so as to facilitate subsequent data processing, thereby ensuring that the calculation structure of the strain on the bottom concrete slab 1 and the magnitude of the shared axial prestress is more accurate. ; Similarly, at least two rows of strain gauges 4 are arranged on the top concrete slab 2, each row of strain gauges 4 is at the same height, and each row of strain gauges 4 is provided with at least three strain gauges 4, and the spacing between two adjacent strain gauges 4 in the same row is the same; all strain gauges 4 on the corrugated steel web 3 are arranged in sequence along the connecting line direction of the top concrete slab 2 and the bottom concrete slab 1, that is, the strain gauges 4 on the corrugated steel web 3 are only arranged in the axial direction (the height direction of the corrugated steel web bridge), the spacing between two adjacent strain gauges 4 is the same, and strain gauges 4 are arranged at the junction of the corrugated steel web 3 and the bottom concrete slab 1, and strain gauges 4 are also arranged at the junction of the corrugated steel web 3 and the top concrete slab 2. It should be noted that in actual testing, the number of strain gauges 4 arranged on the bottom concrete slab 1, the top concrete slab 2 and the corrugated steel web 3 can be set according to their size specifications, and no specific restrictions are made here.

[0039] In the present invention, all strain gauges 4 are connected to the strain tester, and the strain values ​​measured by each strain gauge 4 before tensioning the prestressed tendons on the corrugated steel web bridge and the strain values ​​measured after tensioning the prestressed tendons on the corrugated steel web bridge are collected by the strain tester. The strain tester is wirelessly connected to the control terminal, which transmits the collected strain values ​​to the control terminal. The control terminal calculates the prestressing efficiency of the corrugated steel web bridge according to the received strain values, and the calculation method is as follows:

[0040] S1. Establish a rectangular coordinate system, such as Figure 2As shown, the rectangular coordinate values ​​corresponding to the positions of the strain gauges 4 are obtained, wherein the rectangular coordinate system corresponding to the strain gauges 4 on the bottom concrete slab 1 is (x 1i ,y 1i ), the rectangular coordinate system corresponding to each strain gauge 4 on the corrugated steel web 3 is (x 2j ,y 2j ), the rectangular coordinate system corresponding to each strain gauge 4 on the top concrete slab 2 is (x 3k ,y 3k ); i = 1, 2, 3, ... n, j = 1, 2, 3, ... m, k = 1, 2, 3, ... u, n is the number of strain gauges 4 on the bottom concrete slab 1, m is the number of strain gauges 4 on the corrugated steel web 3, and u is the number of strain gauges 4 on the top concrete slab 2;

[0041] S2. The strain difference corresponding to each strain gauge 4 is obtained according to the strain value measured before and after the prestressed tendons are tensioned by the strain gauge 4. The strain difference before and after the prestressed tendons are tensioned by each strain gauge 4 on the bottom concrete slab 1 is ε 1i , the strain difference of each strain gauge 4 on the corrugated steel web 3 before and after the prestressed tendons are tensioned is ε 2j , the strain difference of each strain gauge 4 on the top concrete slab 2 before and after the prestressed tendons are tensioned is ε 3k ;

[0042] S3, according to the rectangular coordinate system obtained in step S1 and the strain difference obtained in step S2, the fitting functions corresponding to the bottom concrete slab 1, the corrugated steel web 3 and the top concrete slab 2 are obtained, and the fitting functions are specifically obtained by using the Lagrange interpolation method, wherein the fitting function corresponding to the bottom concrete slab 1 is ε1(x1, y1), the fitting function corresponding to the corrugated steel web 3 is ε2(x2, y2); the fitting function corresponding to the top concrete slab 2 is ε3(x3, y3);

[0043] S4, according to the fitting functions obtained in step S3, the axial prestress F1 of the bottom concrete slab 1, the axial prestress F3 of the top concrete slab 2, the axial prestress F2 of the corrugated steel web 3 and the prestressing efficiency η of the corrugated steel web bridge are calculated, wherein,

[0044] 1) The calculation formula for the axial prestress F1 of the bottom concrete slab 1 is:

[0045]

[0046] Where, E1 is the elastic modulus of the bottom concrete slab 1; A1 is the area of ​​the bottom concrete slab 1;

[0047] 2) The calculation formula for the axial prestress F3 of the top concrete slab 2 is:

[0048]

[0049] Where, E3 is the elastic modulus of the top concrete slab 2; A3 is the area of ​​the top concrete slab 2;

[0050] 3) The calculation formula for the axial prestress F2 of the corrugated steel web 3 is:

[0051]

[0052] Where, E2 is the elastic modulus of the corrugated steel web 3; A2 is the area of ​​the corrugated steel web 3;

[0053] 4) The calculation formula for the prestressing efficiency η of the corrugated steel web bridge is:

[0054]

[0055] The above calculation formula of axial prestress is based on F=σA, σ=Eε, plus the fitting function ε(x, y), and is calculated in the form of integration.

[0056] In addition, the present invention also provides a corrugated steel web bridge construction method, which comprises the following steps:

[0057] S1. Build bridge piers. After the bridge piers are built, cast a section of main beam symmetrically along both sides of the bridge piers;

[0058] S2. After a section of the main beam is cast, a strain gauge 4 is arranged on the cross section of the section of the main beam according to the above-mentioned test method for the prestressing efficiency of the corrugated steel web bridge, and the strain gauge 4 is connected to the strain tester, and the strain tester is connected to the control terminal, and the strain gauge 4, the strain tester and the control terminal are debugged;

[0059] S3, tensioning prestressed tendons. The control terminal calculates the axial prestress F1 of the bottom concrete slab 1, the axial prestress F3 of the top concrete slab 2, the axial prestress F2 of the corrugated steel web 3 and the prestressing efficiency η of the corrugated steel web bridge according to the calculation method in the test method of the prestressing efficiency of the corrugated steel web bridge. The control terminal determines the axial prestress F1 of the bottom concrete slab 1 and the axial prestress F3 of the top concrete slab 2 according to the calculation results to determine whether the prestress of the concrete slab meets the requirements. When the judgment result shows that the prestress of the concrete slab does not meet the requirements, the control terminal obtains the increased prestress value according to the insufficient prestress value and the calculated application efficiency, and then controls the tensioning force of the tensioned prestressed tendons according to the obtained increased prestress value until the prestress of the concrete slab meets the requirements. Specifically, in this step, the insufficient prestress value refers to the difference between the axial prestress value of the top concrete slab 2 (or the bottom concrete slab 1) calculated at this stage and the prestress value to be stored in the top concrete slab 2 (or the bottom concrete slab 1), and the increased prestress value is equal to the insufficient prestress value / application efficiency.

[0060] S4. Remove all strain gauges 4, cast another section of main beam, and repeat steps S2-S3 until all main beams are cast. When repeating step S3, the tensioning force of the prestressed tendons is determined by the control terminal according to the prestressing efficiency of the previous section of the main beam and the prestress required to be stored in the concrete slab. That is, when tensioning the prestressed tendons of the next section of the main beam, the prestressing value of the main beam at one end, that is, the tensioning force, is determined according to the prestressing value required to be stored in the concrete slab of the section of the main beam. The specific prestressing value = the prestressing value required to be stored in the concrete slab of the main beam to be prestressed / the prestressing efficiency calculated when tensioning the prestressed tendons of the previous section of the main beam.

[0061] The present invention can calculate the prestressing application efficiency through the above-mentioned testing method. When calculating the prestressing application efficiency, the actual prestressing size shared by the top and bottom concrete slabs 1 and the corrugated steel web 3 is first calculated, and then the prestressing application efficiency is calculated. In the present invention, the prestressing application efficiency refers to the ratio of the prestressing shared (stored) by the top and bottom concrete slabs 1 to the total applied prestressing.

[0062] In the present invention, the calculated actual prestress magnitude of the top and bottom concrete slabs 1 can be used to determine whether the prestress stored in the concrete slabs is sufficient. If the prestress is insufficient, the prestress is increased. The increased prestress value can be obtained based on the insufficient prestress value and the calculated application efficiency. By increasing the prestress value, the prestress stored in the concrete slab is sufficient, thereby ensuring that the concrete slab does not crack. At the same time, the calculated increased prestress value can facilitate the adjustment of the applied prestress value, avoid multiple applications of prestress, and improve construction efficiency.

[0063] In addition, the calculated prestressing efficiency can be used to quickly calculate the required prestressing value based on the prestressing that needs to be stored in the concrete slab and the application efficiency when prestressing other main beams in the future, thereby providing a reference value for the subsequent application of prestressing on the main beams, facilitating construction, saving construction time and improving construction efficiency.

[0064] The above description is a detailed description of the preferred feasible embodiments of the present invention, but the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modified changes completed under the technical spirit suggested by the present invention should fall within the patent scope covered by the present invention.

Claims

1. A test method for the efficiency of prestressing of corrugated steel web bridges, characterized in that: Several strain gauges are attached to the bottom concrete slab, top concrete slab and the outside of the corrugated steel web bridge at intervals. All strain gauges are connected to the strain tester. The strain value measured by each strain gauge before the prestressed tendons on the corrugated steel web bridge are tensioned and the strain value measured after the prestressed tendons on the corrugated steel web bridge are tensioned are collected by the strain tester. The strain tester is wirelessly connected to the control terminal, which transmits the collected strain values ​​to the control terminal. The control terminal calculates the prestressing efficiency of the corrugated steel web bridge according to the received strain values. The calculation method is as follows: S1. Establish a rectangular coordinate system to obtain the rectangular coordinate values ​​corresponding to the positions of each strain gauge, where the rectangular coordinate system corresponding to each strain gauge on the bottom concrete plate is (x 1i ,y 1i ), the rectangular coordinate system corresponding to each strain gauge on the corrugated steel web is (x 2j ,y 2j ), the rectangular coordinate system corresponding to each strain gauge on the top concrete plate is (x 3k ,y 3k ), i = 1, 2, 3, ... n, j = 1, 2, 3, ... m, k = 1, 2, 3, ... u, n is the number of strain gauges on the bottom concrete plate, m is the number of strain gauges on the corrugated steel web, and u is the number of strain gauges on the top concrete plate; S2. The strain difference corresponding to each strain gauge is obtained according to the strain value measured before and after the prestressed tendons are tensioned by the strain gauge. The strain difference before and after the prestressed tendons are tensioned by each strain gauge on the bottom concrete slab is ε 1i , the strain difference of each strain gauge on the corrugated steel web before and after the prestressed tendons are tensioned is ε 2j , the strain difference before and after the prestressed tendons are tensioned on each strain gauge on the top concrete slab is ε 3k ; S3. According to the rectangular coordinate system obtained in step S1 and the strain difference obtained in step S2, the fitting functions corresponding to the bottom concrete slab, the corrugated steel web and the top concrete slab are obtained, wherein the fitting function corresponding to the bottom concrete slab is ε1(x1, y1), the fitting function corresponding to the corrugated steel web is ε2(x2, y2); the fitting function corresponding to the top concrete slab is ε3(x3, y3); S4, according to the fitting functions obtained in step S3, the axial prestress F1 of the bottom concrete slab, the axial prestress F3 of the top concrete slab, the axial prestress F2 of the corrugated steel web and the prestressing efficiency η of the corrugated steel web bridge are calculated, wherein, 1) The calculation formula for the axial prestress F1 of the bottom concrete slab is: Where, E1 is the elastic modulus of the bottom concrete slab; A1 is the cross-sectional area of ​​the bottom slab; 2) The calculation formula for the axial prestress F3 of the top concrete slab is: Where, E3 is the elastic modulus of the top concrete slab; A3 is the cross-sectional area of ​​the top slab; 3) The calculation formula for the axial prestress F2 of the corrugated steel web is: Where, E2 is the elastic modulus of the corrugated steel web; A2 is the area of ​​the corrugated steel web; 4) The calculation formula for the prestressing efficiency η of the corrugated steel web bridge is:

2. The method for testing the prestressing efficiency of a corrugated steel web bridge according to claim 1, characterized in that: At least two rows of strain gauges are arranged on the bottom concrete plate, each row of strain gauges is at the same height, and each row of strain gauges is provided with at least three strain gauges, and the spacing between two adjacent strain gauges in the same row is the same.

3. The method for testing the prestressing efficiency of a corrugated steel web bridge according to claim 1, characterized in that: At least two rows of strain gauges are arranged on the top concrete plate, each row of strain gauges is at the same height, and each row of strain gauges is provided with at least three strain gauges, and the spacing between two adjacent strain gauges in the same row is the same.

4. The method for testing the prestressing efficiency of a corrugated steel web bridge according to claim 1, characterized in that: All strain gauges on the corrugated steel web are arranged in sequence along the connecting line direction of the top concrete plate and the bottom concrete plate, the spacing between two adjacent strain gauges is the same, and strain gauges are arranged at the junction of the corrugated steel web and the bottom concrete plate, and strain gauges are also arranged at the junction of the corrugated steel web and the top concrete plate.

5. The method for testing the prestressing efficiency of a corrugated steel web bridge according to claim 1, characterized in that: The fitting function obtained in step S3 is obtained by using the Lagrange interpolation method.

6. A method for constructing a corrugated steel web bridge, characterized in that: The steps include: S1. Build bridge piers. After the bridge piers are built, cast a section of main beam symmetrically along both sides of the bridge piers; S2. After a section of the main beam is cast, a strain gauge is arranged on the cross section of the section of the main beam according to the test method for the prestressing efficiency of the corrugated steel web bridge as described in any one of claims 1 to 5, and the strain gauge is connected to the strain tester, and the strain tester is connected to the control terminal, and the strain gauge, the strain tester and the control terminal are debugged; S3, tensioning prestressed tendons, the control terminal calculates the axial prestress F1 of the bottom concrete slab, the axial prestress F3 of the top concrete slab, the axial prestress F2 of the corrugated steel web and the prestressing efficiency η of the corrugated steel web bridge according to the calculation method in the test method of the prestressing efficiency of the corrugated steel web bridge, and the control terminal determines the axial prestress F1 of the bottom concrete slab and the axial prestress F3 of the top concrete slab according to the calculation results to determine whether the prestress of the concrete slab meets the requirements. When the judgment result shows that the prestress of the concrete slab does not meet the requirements, the control terminal obtains the increased prestress value according to the insufficient prestress value and the calculated application efficiency, and then controls the tensioning force of the tensioned prestressed tendons according to the obtained increased prestress value until the prestress of the concrete slab meets the requirements; S4. Remove all strain gauges, cast another section of main beam, and repeat steps S2-S3 until all main beams are cast. When repeating step S3, the tensioning force of the prestressed tendons is determined by the control terminal based on the prestressing efficiency of the previous section of the main beam and the prestress required to be stored in the concrete slab.

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