Method for evaluating performance of waterproof adhesive layer of steel bridge deck in marine environment

Abstract

The present application belongs to the technical field of service life evaluation of steel bridge deck in marine environment, and discloses an evaluation method for the performance of waterproof bonding layer of steel bridge deck in marine environment. The method effectively solves the problem that there is no evaluation method for the performance of waterproof bonding layer of steel bridge deck under the comprehensive influence of moisture, salt and high temperature environment. The method comprises the following steps: firstly, polishing and rust removing treatment is performed on the surface of the steel plate, and then anti-rust treatment is performed; then, the waterproof bonding layer is spread on the upper surface of the steel plate, and then SMA asphalt mixture is spread to form a composite test piece; the composite test piece is tested by using an aging evaluation device, the bonding strength and shear strength of the composite test piece under different temperatures and salt mists under certain humidity conditions are tested, and bonding strength model and shear strength model are fitted according to the results; and the influence of temperature and salt mist on the waterproof bonding layer is evaluated by using the bonding strength model and shear strength model. The present application has important significance for the material selection and dosage of the waterproof bonding layer.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of service life evaluation of steel bridge deck in marine environment, and particularly relates to a method for evaluating the performance of waterproof bonding layer of steel bridge deck in marine environment. BACKGROUND

[0002] The service life of steel bridge deck pavement layer is about 15 years, while the design service life of the bridge is more than 100 years, so it is of great significance to protect the bridge structure from being eroded and damaged by external factors. At present, external environmental conditions have a great influence on the service life of the bridge, especially the influence of moisture, salt and high temperature on the steel bridge deck, so the performance requirements of the waterproof bonding layer of the steel bridge deck are more stringent.

[0003] At present, there is no evaluation method for the performance of the waterproof bonding layer of the steel bridge deck under the comprehensive influence of moisture, salt and high temperature environment, so it is particularly important to seek an evaluation method for the performance of the waterproof bonding layer of the steel bridge deck under marine environment. SUMMARY

[0004] The purpose of the present application is to provide a method for evaluating the performance of the waterproof bonding layer of the steel bridge deck in marine environment, which effectively solves the problem that there is no evaluation method for the performance of the waterproof bonding layer of the steel bridge deck under the comprehensive influence of moisture, salt and high temperature environment.

[0005] To solve the above technical problems, the technical solution adopted by the present application is: a method for evaluating the performance of the waterproof bonding layer of the steel bridge deck in marine environment, comprising the following steps: S1, first polish and rust removal treatment is performed on the surface of the steel plate, and then rust prevention treatment is performed on the surface of the steel plate; S2, a waterproof bonding layer is spread on the surface of the steel plate, and then SMA asphalt mixture is spread to form a composite test piece; S3, an aging evaluation device capable of simulating marine environment is used to test the composite test piece under different temperatures and salt mist under certain humidity conditions, and the bonding strength and shear strength of the composite test piece are tested, and a bonding strength model and a shear strength model are fitted according to the results; S4, the influence of temperature and salt mist on the waterproof bonding layer is evaluated by the bonding strength model and the shear strength model.

[0006] Further, in step S3, the bonding strength model is:

[0007] ;

[0008] wherein, represents the bonding strength; represents the initial bonding strength; represents the temperature influence coefficient; represents the environmental temperature; represents the aging time; represents a concentration influence coefficient; represents a concentration of sodium chloride solution.

[0009] the shear strength The model is:

[0010] ;

[0011] wherein, represents the shear strength, represents the initial shear strength.

[0012] Further, the aging evaluation device comprises a test piece compaction unit, an environment adjusting unit and an environment box, the test piece compaction unit is used for compacting the composite test piece, the environment adjusting unit is used for adjusting and controlling the temperature and the salt mist concentration in the environment box for a certain time length, and the environment box is used for providing a test space for the composite test piece, so that the waterproof adhesive layer of the composite test piece is fully contacted with the temperature and the salt mist factor set by the environment adjusting unit.

[0013] Further, the test piece compaction unit comprises a base, a detachable test piece sleeve used for containing the composite test piece, and a hydraulic compactor used for compacting the composite test piece, the base is provided with a groove, the bottom end of the detachable test piece sleeve is arranged in the groove, and the output end of the hydraulic compactor is located directly above the detachable test piece sleeve.

[0014] Further, the environment adjusting unit comprises a control panel, a water tank and a sodium chloride solution tank, and the control panel is used for controlling the liquid output of the water tank and the sodium chloride solution tank.

[0015] The environment box comprises a top cover used for sealing the environment box, a salt mist injection port, and a rotating disc and a heating ring arranged at the bottom of the environment box, the outlets of the water tank and the sodium chloride solution tank are in communication with the salt mist injection port, a plurality of test piece fixing holes used for fixing the composite test piece are arranged on the rotating disc, a fan is arranged at the middle portion of the lower surface of the top cover, and the fan, the rotating disc and the heating ring are connected with the control panel.

[0016] Further, the control panel is provided with a water mist input switch, a sodium chloride solution input switch, a temperature adjusting knob and a time adjusting knob.

[0017] Further, when the material of the waterproof adhesive layer is epoxy resin, in the bonding strength model, the value of the temperature influence coefficient is 0.00092 , and the value of the concentration influence coefficient is 0.0081 ; in the shear strength model, the value of the temperature influence coefficient is 0.0011 , and the value of the concentration influence coefficient is 0.012 .

[0018] Compared with the prior art, the beneficial technical effects of the present application are: the present application can conveniently and quickly simulate the influence of various factors in the marine environment on the steel bridge deck adhesive layer through the aging evaluation device, and can study the specific influence of each variable by adjusting different variables; at the same time, the bonding strength model and the shear strength model are fitted by the test data measured by the aging evaluation device, and the bonding strength model and the shear strength model can quickly evaluate the influence of the waterproof adhesive layer under various environmental conditions, which helps to control the materials in the construction of the cross-sea bridge and understand the influence of the materials in the marine environment on the performance of the materials, and has important significance for the selection and amount of the waterproof adhesive layer. It provides an important basis for improving the overall performance of the steel bridge deck pavement in the marine environment, and has good engineering application prospect and popularization value. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural schematic diagram of the aging evaluation device of the present application.

[0020] Figure 2 is a structural schematic diagram of the aging evaluation device of the present application after removing the top cover.

[0021] Figure 3 is a structural schematic diagram of the top cover of the aging evaluation device of the present application.

[0022] BRIEF DESCRIPTION OF DRAWINGS: Test piece compaction unit-1; Environmental regulation unit-2; Environmental box-3; Base-4; Removable test piece sleeve-5; Hydraulic compactor-6; Top cover-7; Salt spray injection port-8; Rotary disc-9; Copper pipe heating ring-10; Test piece fixing hole-11; Fan-12. DETAILED DESCRIPTION

[0023] Example 1: The evaluation method of the performance of the waterproof adhesive layer of the steel bridge deck in the marine environment, comprising the following steps: S1, selecting a circular steel plate, first polishing the surface of the circular steel plate to remove rust treatment, so that the surface approaches the SA2.5 rust removal standard, and performing rust prevention treatment on the surface.

[0024] S2, laying polyurethane modified epoxy resin chip waterproof adhesive layer on the surface of the steel plate by layer paving method, and then laying SMA asphalt mixture to form a composite test piece.

[0025] S3, using an aging evaluation device capable of simulating the marine environment to test the composite test piece, testing the bonding strength and shear strength of the composite test piece under different temperatures and salt spray under certain humidity conditions, and fitting the bonding strength model and the shear strength model according to the results. The bonding strength model and the shear strength model are used to evaluate the influence of the waterproof adhesive layer on temperature and salt spray.

[0026] For example, Figure 1As shown in the figure, the aging evaluation device comprises a test piece compaction unit 1, an environment adjusting unit 2 and an environment box 3. The test piece compaction unit 1 is used for compacting the composite test piece, the environment adjusting unit 2 is used for adjusting and controlling the temperature and the salt mist concentration under a certain time length and humidity in the environment box 3, and the environment box 3 is used for providing a test space for the composite test piece so that the waterproof adhesive layer of the composite test piece is fully contacted with the humidity, temperature and salt mist factors set by the environment adjusting unit 2.

[0027] As shown in the figure, Figure 1 and Figure 2 the test piece compaction unit 1 comprises a base 4, a detachable test piece sleeve 5 for containing the composite test piece and a hydraulic compactor 6 for compacting the composite test piece. The base 4 is provided with a recess, the bottom end of the detachable test piece sleeve 5 is arranged in the recess, and the output end of the hydraulic compactor 6 is located directly above the detachable test piece sleeve 5. The output pressure of the hydraulic compactor 6 can be controlled.

[0028] As shown in the figure, Figure 1 and Figure 2 the environment adjusting unit 2 comprises a control panel, a water tank and a sodium chloride solution tank. The control panel is used for controlling the liquid output of the water tank and the sodium chloride solution tank. In this embodiment, an atomizer is arranged in each of the water tank and the sodium chloride solution tank. The control panel is provided with a water mist input switch, a sodium chloride solution input switch, a temperature adjusting knob and a time adjusting knob.

[0029] As shown in the figure, Figure 2 and Figure 3 the environment box 3 comprises a top cover 7 for sealing the environment box, a salt mist injection port 8 and a rotating disc 9 and a copper pipe heating ring 10 arranged at the bottom of the environment box 3. The outlets of the water tank and the sodium chloride solution tank are communicated with the salt mist injection port 8. An air blower is arranged at the salt mist injection port 8. The rotating disc 9 is provided with a plurality of test piece fixing holes 11 for fixing the composite test piece. A fan 12 is arranged at the middle of the lower surface of the top cover 7. The air blower, the fan 12, the rotating disc 9 and the copper pipe heating ring 10 are connected with the control panel. The entire environment box 3 is a closed space.

[0030] The steps for testing the composite specimen using an aging assessment device are as follows: (1) Assemble the detachable specimen sleeve, place it on the base, and apply oil to the detachable specimen sleeve. Place the composite specimen inside the detachable specimen sleeve and start the hydraulic compactor to compact the composite specimen. (2) Disassemble the detachable specimen sleeve, take out the compacted composite specimen, place the composite specimen in the specimen fixing hole in the environmental chamber, ensure that the waterproof adhesive layer and the asphalt layer of the composite specimen are exposed outside the specimen fixing hole, cover the top cover, and ensure that the environmental chamber is sealed. (3) Add purified water and 5% sodium chloride solution to the water tank and sodium chloride solution tank respectively. Turn on the water mist input switch, sodium chloride solution input switch, and temperature adjustment knob. Set the time using the time adjustment knob. After setting the time, the copper tube heating coil adjusts the temperature inside the environmental chamber according to the set time. Salt mist and water mist enter the environmental chamber through the salt mist injection port. The rotating disc rotates slowly, and the fan works at the same time to ensure that all factors inside the environmental chamber are in full contact with the composite specimen. After the test, the composite specimen is taken out and its bonding strength and shear strength are tested. The test results are shown in Table 1.

[0031] Table 1. Bond strength and shear strength of composite specimens under certain humidity, at different durations, temperatures, and salt spray concentrations.

[0032]

[0033] Based on the above experimental data, an exponential decay model with the synergistic effect of multiple factors was selected to determine the bond strength. The general model is:

[0034] ;

[0035] Using the least squares method, the initial strength :Pick Four groups of bond strength The calculated average value is 3.98 MPa, that is:

[0036] ;

[0037] With the objective of minimizing the sum of squared residuals between the experimental and predicted bond strength values, the following fit was obtained: , That is, in the bond strength model, the temperature influence coefficient... The value is 0.00092. Concentration influence coefficient The value is 0.0081. .

[0038] Similarly, based on the above experimental data, an exponential decay model with the synergistic effect of multiple factors was selected to determine the shear strength. The general model is:

[0039] ;

[0040] Using the least squares method, the initial strength :Pick Four groups of shear strength The calculated average value is 3.08 MPa, that is:

[0041] ;

[0042] With the objective of minimizing the sum of squared residuals between the experimental and predicted shear strength values, the following fit was obtained: , That is, in the shear strength model, the temperature influence coefficient The value is 0.0011. The concentration influence coefficient is set to 0.012. It is worth noting that the waterproof adhesive layer material selected in this embodiment is epoxy resin. Therefore, the initial strength and the influence coefficients of temperature and concentration obtained in this embodiment should not be used as the evaluation basis for other materials.

[0043] Based on the above experimental data, from the coefficient of determination ( The fitting effects of the bond strength model and shear strength model obtained in this embodiment are evaluated from three aspects: residual analysis and worst-case working conditions.

[0044] (1) Coefficient of determination ( This reflects the model's ability to interpret data. The closer the value is to 1, the better the fit. In this embodiment, the bond strength model... This indicates that the model can explain 98.8% of the data. Changes; shear strength model This indicates that the model can explain 99.3% of the data. The changes are evident. Therefore, the fitting accuracy of both the bond strength model and the shear strength model meets the requirements for engineering applications.

[0045] (2) The residual analysis results of bond strength and shear strength are shown in Table 2 and Table 3, respectively. As can be seen from Table 2 and Table 3, the relative error of all data points is less than 5%, and the fitting model is in good agreement with the experimental data.

[0046] (3) Under the most unfavorable working conditions ( ) Verification: the model calculated value of the bonding strength is 1.53 MPa, the test value of the bonding strength is 1.48 MPa, the error of the calculated value and the test value is only 3.4%; the model calculated value of the shear strength is 0.87 MPa, the test value of the shear strength is 0.83 MPa, the error of the calculated value and the test value is only 4.8%. The errors are all less than 5%, indicating that the reliability of the bonding strength model and the shear strength model provided in the embodiment is high.

[0047] Table 2 Residual analysis of the bonding strength

[0048]

[0049] Table 3 Residual analysis of the shear strength

[0050]

[0051] Of course, the above description is not a limitation on the present application, and the present application is not limited to the above examples. Changes, modifications, additions or replacements made by those skilled in the art within the essential scope of the present application shall also belong to the protection scope of the present application.

Claims

1. A method for evaluating the performance of a waterproofing adhesive layer for a steel bridge deck in a marine environment, characterized by, The method comprises the following steps: S1, polishing and rust removing the surface of the steel plate, and then performing rust-proof treatment on the surface of the steel plate; S2, spreading a waterproof bonding layer on the surface of the steel plate, and then spreading SMA asphalt mixture to form a composite test piece; S3, using an aging evaluation device capable of simulating marine environment to test the composite test piece, testing the bonding strength and shear strength of the composite test piece under different temperatures and salt mist under certain humidity conditions, and fitting a bonding strength model and a shear strength model according to the results; S4, evaluating the influence of temperature and salt mist on the waterproof bonding layer through the bonding strength model and the shear strength model; In step S3, the adhesive strength The model is: ； wherein, represents the cohesive strength; represents the initial cohesive strength; represents the temperature influence coefficient; represents the ambient temperature; represents the aging time; represents the concentration influence coefficient; represents the sodium chloride solution concentration; The shear strength The model is: ； wherein, represents the shear strength, represents the initial shear strength; The aging evaluation device comprises a test piece compaction unit, an environment adjusting unit and an environment box, the test piece compaction unit is used for compacting the composite test piece, the environment adjusting unit is used for adjusting and controlling the temperature and salt mist concentration in the environment box for a certain time, and the environment box is used for providing a test space for the composite test piece, so that the waterproof bonding layer of the composite test piece fully contacts the temperature and salt mist factors set by the environment adjusting unit.

2. The method for evaluating the performance of a waterproof adhesive layer of a steel deck in a marine environment according to claim 1, characterized by, The test piece compaction unit comprises a base, a detachable test piece sleeve for containing the composite test piece, and a hydraulic compactor for compacting the composite test piece, the base is provided with a groove, the bottom end of the detachable test piece sleeve is arranged in the groove, and the output end of the hydraulic compactor is located directly above the detachable test piece sleeve.

3. The method for evaluating the performance of a waterproof adhesive layer of a steel deck in a marine environment according to claim 2, characterized by, The environment adjusting unit comprises a control panel, a water tank and a sodium chloride solution tank, the control panel is used for controlling the liquid output of the water tank and the sodium chloride solution tank; The environment box comprises a top cover for sealing the environment box, a salt mist injection port, a rotating disc and a heating ring arranged at the bottom of the environment box, the outlets of the water tank and the sodium chloride solution tank are in communication with the salt mist injection port, the rotating disc is provided with a plurality of test piece fixing holes for fixing the composite test piece, a fan is arranged at the middle of the lower surface of the top cover, and the fan, the rotating disc and the heating ring are connected with the control panel.

4. The method for evaluating the performance of a waterproof adhesive layer of a steel deck in a marine environment according to claim 3, characterized by, The control panel is provided with a water mist input switch, a sodium chloride solution input switch, a temperature adjusting knob and a time adjusting knob.

5. The method of evaluating the performance of a waterproofing bond coat for steel bridge decks in marine environments according to claim 1, characterized in that, When the material of the waterproof adhesive layer is epoxy resin, the value of the temperature influence coefficient in the adhesive strength model is 0.00092 , the value of the concentration influence coefficient is 0.0081 ; in the shear strength model, the value of the temperature influence coefficient is 0.0011 , and the value of the concentration influence coefficient is 0.012 .

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