CN111171786B

CN111171786B - Photocatalyst-based bridge deck waterproof bonding layer material and preparation method thereof

Info

Publication number: CN111171786B
Application number: CN202010079144.6A
Authority: CN
Inventors: 张洪亮; 吕文江; 刘彤; 杨龙飞; 巩大力; 李德文; 张�浩
Original assignee: Changan University
Current assignee: Changan University
Priority date: 2020-02-03
Filing date: 2020-02-03
Publication date: 2021-08-27
Anticipated expiration: 2040-02-03
Also published as: CN111171786A

Abstract

The invention discloses a bridge deck waterproof bonding layer material based on a photocatalyst and a preparation method thereof, wherein the bridge deck waterproof bonding layer material comprises a component A and a component B, and the component A comprises the following components in percentage by weight: the component B is 1: 2.0-1: 2.9; wherein: the component A comprises unsaturated polyester resin, nano-SiO2, a photoinitiator and a coupling agent; the component B comprises asphalt and a compatilizer. In the component A, the weight ratio of unsaturated polyester resin: nano-SiO 2: photoinitiator (2): coupling agent 100:3:4: 3; in the component B, asphalt: compatibilizer 100: 4. the bridge deck pavement waterproof bonding layer material has good toughness, strong impact resistance, high strength and low brittleness; the bonding, tensile and shear resistance performance is good; the waterproof performance is excellent, and the durability is good; convenient construction, better environmental protection and lower cost.

Description

Photocatalyst-based bridge deck waterproof bonding layer material and preparation method thereof

Technical Field

The invention belongs to the field of bridge deck paving materials, and particularly relates to a photocatalyst-based bridge deck waterproof bonding layer material and a preparation method thereof.

Background

After 2000, the economy went up the motorway and traffic infrastructure construction, including road construction, developed rapidly. Along with the large-scale construction of urban roads and highways, a large number of bridges are used by traffic. The bridge is an important node forming a transportation network, heavy traffic flow is borne, normal vehicle passing can be influenced by damage of any part on the bridge, and a large amount of waste and loss of economic and time cost are caused.

Bridge deck pavement is an important component of the overall bridge structure and has important influence on the accessibility of the bridge and the durability of the overall bridge structure. The waterproof bonding layer is positioned between the leveling layer and the asphalt pavement layer, and plays an important and key role in the durability and the road performance of the bridge deck pavement layer. The intrusion of rain or other water sources is one of the most direct and important factors causing damage to the bridge deck. The waterproof bonding material with excellent performance and the treatment of the good waterproof bonding layer are important measures for improving the durability of the bridge pavement structure and prolonging the service life of the whole bridge. The materials of the waterproof bonding layer commonly used in China include hot-melt bonding materials, solvent bonding agents and thermosetting bonding materials. The hot melt adhesive material has certain deformability and good waterproof sealing effect, but is easy to soften at high temperature, so that the adhesive force is reduced; the solvent-based binder material has the defect of high-temperature softening, and when the solvent-based binder material is paved, the heat-sensitive substances contained in the solvent-based binder material contact the asphalt pavement layer at high temperature to release gas, so that the pavement layer generates bubbles; thermosetting adhesive materials, such as epoxy asphalt, are expensive, have a high shear strength at high temperatures, lose the ability to bond the asphalt pavement and the cement substrate, and thus, the adhesive layer becomes a relatively weak slip layer, which is liable to cause diseases such as shifting and cracking of the asphalt pavement.

The key point for preparing the waterproof bonding layer material is to select a proper initiator, and common initiators comprise a normal-temperature initiator and a high-temperature initiator. When the normal-temperature inducer is used, in the process of preparing UP asphalt, the fact that a large amount of bubbles are generated and the reaction is violent when methyl ethyl ketone peroxide is added into a hot asphalt and resin system is found, and the UP asphalt prepared at the later stage cannot be subjected to curing reaction at normal temperature and cannot form strength. The poplar and dragon flies use a high-temperature initiator to prepare a waterproof bonding layer material, and the high-temperature initiator has an explosion tendency and low safety after being subjected to friction, impact, fire or other ignition sources. Therefore, we tried to prepare a water-repellent adhesive layer material using a photoinitiator.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention provides a bridge deck waterproof bonding layer material based on a photocatalyst and a preparation method thereof, and the bridge deck waterproof bonding layer material has good toughness, strong impact resistance, high strength and low brittleness; the bonding, tensile and shear resistance performance is good; the waterproof performance is excellent, and the durability is good; convenient construction, better environmental protection and lower cost.

In order to solve the technical problems, the invention is realized by the following technical scheme:

a bridge deck waterproof bonding layer material based on a photocatalyst comprises a component A and a component B, wherein the component A comprises the following components in parts by weight: the component B is 1: 2.0-1: 2.9; wherein:

the component A comprises unsaturated polyester resin and nano-SiO₂A photoinitiator and a coupling agent;

the component B comprises asphalt and a compatilizer.

Further, in the component A, the weight ratio of unsaturated polyester resin: nano-SiO₂: photoinitiator (2): coupling agent 100:3:4: 3; in the component B, asphalt: compatibilizer 100: 4.

further, the unsaturated polyester resin is bisphenol A type unsaturated polyester resin, and the solid content of the unsaturated polyester resin is 57.0-63.0%.

Further, the photoinitiator is Omnirad 819.

Further, the nano-SiO₂Is A type nano-SiO₂The silica content was 98.5%.

Further, the coupling agent is KH-570 silane coupling agent.

Further, the asphalt is SBS modified asphalt, the penetration degree is 85.7, the softening point is 47.2, the dynamic viscosity is 156.8, and the ductility is more than 100.

Further, the compatibilizer is maleic anhydride with a solids content > 99.5%.

A preparation method of a bridge deck waterproof bonding layer material based on a photocatalyst comprises the following steps:

the method comprises the following steps: coupling agent is adopted to react nano-SiO₂Carrying out surface organic modification;

step two: carrying out surface organic modification on the nano-SiO obtained in the step one₂The photoinitiator and the unsaturated polyester resin are mixed evenlyObtaining a component A;

step three: uniformly mixing the asphalt and the compatilizer to obtain a component B;

step four: and (4) uniformly mixing the component A obtained in the step (II) with the component B obtained in the step (III) to obtain the bridge deck waterproof bonding layer material.

Further, before the first step is carried out, nano-SiO is added₂Pretreating for 40-60 min under the conditions of alcohol-water solution, 100 ℃ and pH value of 4; in the alcohol-water solution, the volume ratio of ethanol to water is 10: 1.

compared with the prior art, the invention has at least the following beneficial effects: the invention relates to a bridge deck waterproof bonding layer material based on a photocatalyst, which adopts a photoinitiator, wherein the main reaction mechanism is that the photoinitiator absorbs radiation energy of near ultraviolet light to cause the photoinitiator to decompose and generate active free radicals to initiate monomers (oligomers) to polymerize and crosslink to form a final cured product. The inorganic nano particle modified UP not only can realize the reinforcing effect of a UP condensate, but also can simultaneously take the properties of toughness and the like into consideration; in particular, nano-SiO₂The thixotropy, the impermeability, the abrasion resistance, the heat resistance and other properties of UP can be improved; at the same time, nano-SiO₂The modified UP asphalt used for the bridge deck waterproof bonding layer can have excellent road performance such as fatigue resistance, water resistance, good interlayer bonding capability and the like, and meanwhile, the modified UP asphalt has low engineering cost and great economic benefit and application prospect. The photoinitiator has the advantages of low price, simple synthesis, no toxicity and odor of the photoinitiator and a photocracking product thereof, good stability, convenience for long-time storage and the like, and has more advantages in preparing the waterproof bonding layer by adopting the photoinitiator compared with a normal-temperature initiator and a high-temperature initiator.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below, and it is apparent that the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As a specific embodiment of the invention, the bridge deck waterproof bonding layer material based on the photocatalyst comprises a component A and a component B, wherein the component A comprises the following components in percentage by weight: the component B is 1: 2.0-1: 2.9.

wherein the component A comprises unsaturated polyester resin and nano-SiO₂A photoinitiator and a coupling agent; in the component A, the weight ratio of unsaturated polyester resin: nano-SiO₂: photoinitiator (2): coupling agent 100:3:4: 3.

the component B comprises asphalt and a compatilizer; in the component B, the weight ratio of asphalt: compatibilizer 100: 4.

wherein, the unsaturated polyester resin is bisphenol A type unsaturated polyester resin, and the solid content is 57.0 to 63.0 percent; specifically, unsaturated resin polyester and styrene are adopted, and the resin is prepared from the following components in parts by weight: styrene 65.5 wt.%: 34.5 wt.%, bisphenol a type unsaturated polyester resin was prepared. The photoinitiator is Omnirad 819, is yellow powder in appearance, has a melting point of 127-133 ℃, and is dissolved in organic solvents such as acetone and acetonitrile. The nano-SiO2 is A type nano-SiO₂The silica content was 98.5%. The coupling agent is KH-570 silane coupling agent, and the content of the coupling agent is 97%. The asphalt is SBS modified asphalt with penetration of 85.7, softening point of 47.2, dynamic viscosity of 156.8 and ductility>100. The compatilizer is maleic anhydride (maleic anhydride) with solid content>99.5％。

The invention relates to a preparation method of a bridge deck waterproof bonding layer material based on a photocatalyst, which comprises the following steps:

the method comprises the following steps: mixing nano-SiO₂Pretreating for 40-60 min under the conditions of alcohol-water solution, 100 ℃ and pH value of 4; in the alcohol-water solution, the volume ratio of ethanol to water is 10: 1; coupling agent is adopted to react nano-SiO₂Carrying out surface organic modification;

step two: adopting a 'first doping' mode to organically modify the surface of the nano-SiO obtained in the step one₂Adding the photoinitiator into unsaturated polyester resin, and shearing in a high-speed shearing machine at the speed of 2000r/min for 20min to obtain nano-SiO₂A modified A component;

step three: adding the compatilizer into the asphalt, and stirring for 10-20 minutes to uniformly disperse the compatilizer to obtain a component B;

step four: mixing the component A obtained in the step two with the component B obtained in the step three, and shearing at the speed of 4000r/min for 40min to obtain nano-SiO₂Modified UP asphalt, namely a bridge deck waterproof bonding layer material.

The present invention is described in further detail below with reference to specific examples.

Example 1

A bridge deck waterproof bonding layer material based on a photocatalyst is prepared according to the following mixture ratio:

according to the proportion of the component A to the component B of 1:2.0, the component A comprises the following components: a-type nano-SiO₂: omnirad 819 photoinitiator: the KH-570 silane coupling agent is 100:3:4:3, and the component B is asphalt and maleic anhydride compatilizer is 100: 4.

A bridge deck waterproof bonding layer material based on a photocatalyst is prepared according to the following steps:

the method comprises the following steps: KH-570 silane coupling agent is adopted to couple A type nano-SiO₂Carrying out surface organic modification;

step two: adopting a mode of 'doping firstly' to organically modify the surface of the A-type nano-SiO obtained in the step one₂Adding Omnirad 819 photoinitiator into A-type unsaturated polyester resin, and shearing in a high-speed shearing machine at the speed of 2000r/min for 20min to obtain nano-SiO₂A modified A component;

step three: adding a maleic anhydride compatilizer into the modified asphalt, and stirring for 10-20 minutes to uniformly disperse the maleic anhydride compatilizer to obtain a component B;

step four: mixing the component A obtained in the step two with the component B obtained in the step three, and shearing at the speed of 4000r/min for 40min to obtain nano-SiO₂And modifying UP asphalt to obtain the bridge deck waterproof bonding layer material.

Screening tests of coarse aggregates, fine aggregates and mineral powder are carried out on the three-grade materials of 3-5 mm, 5-10 mm and 10-20 mm according to T0302-2005, T0327-2005 and T0351-2005, and grading design of the AC-20 asphalt mixture is carried out by selecting an oilstone ratio of 4.3%.

In order to carry out follow-up research on the road performance, the bridge deck pavement composite board is prepared by the following steps:

the method comprises the steps of adopting a water-cement ratio of 0.41, selecting a polycarboxylic acid high-efficiency water reducing agent as a water reducing agent, wherein the mixing amount of the water reducing agent is 1.1 percent of the using amount of cement, firstly filling the mixed cement concrete into a 30cm multiplied by 5cm test mould, placing the test mould in a standard environment for curing for 28 days, adopting a napping surface treatment mode, then placing the prefabricated cement concrete slab into a 30cm multiplied by 10cm track slab test mould, padding paper on the periphery of the test mould, and uniformly smearing nano-SiO by using a soft brush₂The modified UP asphalt waterproof bonding material (bridge deck waterproof bonding layer material) prevents the waterproof bonding material from flowing to the edge. And after the composite board is cured and formed, loading the AC-20 mixture on the bonding layer by using a track forming instrument, placing for more than 1d, and then demoulding to obtain the bridge deck pavement composite board.

Example 2

Example 2 differs from example 1 in that the a component and the B component are 1: 2.3.

Example 3

Example 3 differs from example 1 in that the a component and the B component are 1: 2.6.

Example 4

Example 4 differs from example 1 in that the a component and the B component are 1: 2.3.

Example 5

Example 5 differs from example 1 in that the a component and the B component are 1: 2.9.

Comparative example 1

Comparative example 1 differs from example 1 in that the bituminous waterproofing binder material used in comparative example 1 is a base bitumen.

Comparative example 2

Comparative example 2 is different from example 1 in that the asphalt waterproofing binder material used in comparative example 2 is SBR-modified asphalt.

Comparative example 3

Comparative example 3 is different from example 1 in that the waterproof adhesive layer material of asphalt used in comparative example 3 is SBS modified emulsified asphalt.

Comparative example 4

Comparative example 4 is different from example 1 in that the asphalt waterproofing binder material used in comparative example 4 is SBR-modified emulsified asphalt.

Tensile test and DSR test are carried out on the examples 1-5, the optimum proportion of A, B components is analyzed, so that the pavement performance of waterproof bonding layers made of different asphalt materials can be further compared and researched, and the test conditions are as follows:

tensile test

The test pieces of examples 1 to 5 were subjected to tensile tests in accordance with road engineering asphalt and asphalt mixture test protocol JTG E20-2011, and the test results are shown in table 1.

TABLE 1

	Tensile Strength (MPa)	Elongation at Break (%)
			Example 1	2.0	205
Example 2	1.95	218
			Example 3	1.92	238
Example 4	1.6	245
			Example 5	1.5	252

As is apparent from Table 1, as the ratio of the A component (UP after modification) to the B component (asphalt and various additives) increases (from 1:2.0 to 1:2.9), the tensile strength gradually decreases and the elongation at break gradually increases. Nano-SiO when the ratio of the A component (modified UP) to the B component (asphalt and various additives) is 1:2.6₂The elongation strength and elongation at break of the modified UP bitumen are at relatively large values, so that the optimum ratio of the A component (UP after modification) to the B component (bitumen and various additives) is considered to be 1: 2.6.

DSR test

The samples of examples 1 to 5 were subjected to Dynamic Shear Rheology (DSR) tests according to the specification ASTM-D4402, and the results of the complex shear modulus (G), phase angle (δ) and rutting factor (G x/sin δ) tests are shown in Table 2.

TABLE 2

	G*/sinδ
		Example 1	11
Example 2	10
		Example 3	8.5
Example 4	6
		Example 5	3

As shown in Table 2, as the ratio of A to B was varied (1:2.0 to 1:2.9), nano-SiO was observed₂The rutting factor of the modified UP asphalt is gradually reduced, which shows that the high-temperature shear resistance of the modified UP asphalt is reduced. The A: B ratio (1: 2.0-1: 2.6) decreases gradually, and then the A: B ratio (1: 2.6-1: 2.9) decreases rapidly. From the viewpoint of rutting factor, a: B is 1:2.0 optimal, but from the results in table 1, the elongation at break of nano-SiO2 modified UP asphalt is too low, the bond is too brittle to satisfy sufficient deformability.

Combining the tensile and DSR test results, when A: B is 1:2.6, the nano-SiO2 modified UP asphalt has higher tensile strength, elongation at break and rutting factor, and the strength, toughness and high-temperature shear resistance are in better ranges, so that the required performance of the bonding layer at normal temperature and high temperature can be better met.

The test pieces of example 3 and comparative examples 1 to 4 were subjected to related tests, and road performance was contrastively studied, wherein the test conditions were as follows:

water penetration test

Referring to the T0971-2008 asphalt pavement water seepage coefficient test method, the water seepage instrument adopted in the test is to lengthen the original 600mm glass tube of the pavement water seepage tester by 800mm to 1400mm, and increase the hydrostatic pressure, so as to better test the water seepage resistance of the waterproof bonding layer. The test results are shown in Table 3

TABLE 3

As can be seen from Table 3, the water penetration heights of example 3 at different times are all 0mm, which shows that the water penetration resistance of example 3 is better than that of other examples.

2. Test of resistance to construction damage

A layer of hot aggregate is spread on a cement concrete slab coated with a waterproof bonding layer, then rolling is carried out on a track forming instrument, after rolling for a certain number of times, the aggregate is peeled off, the damage condition of the waterproof bonding layer is observed, a water seepage test is carried out, the falling height of a water column of the water seepage instrument is recorded, and the test result is shown in table 4.

TABLE 4

As can be seen from table 4, the five waterproof bonding layers were subjected to the construction damage resistance test, and example 3 had few partial punctures, comparative example 1 and comparative example 2 had partial punctures, and both comparative example 3 and comparative example 4 had most punctures; after the water seepage test, the water seepage height of the example 3 is smaller than that of the materials of other examples, which shows that the construction damage resistance of the bonding layer formed by the materials of the example 3 is optimal.

3. Resistance to water immersion

In order to study the influence of water and temperature on the bonding performance of the bonding layer, the samples were respectively soaked in water baths at 20 ℃ and 40 ℃ for 24h, 48h and 72h, then the shear tests were respectively carried out, and simultaneously the samples which were not soaked were compared, and the test results are shown in tables 5 and 6.

TABLE 5

TABLE 6

As shown in tables 5 and 6, the shear strength of the five waterproof adhesive materials decreased to different degrees at the same temperature with the increase of the soaking time, and the decrease curve of the residual shear strength ratio in example 3 was much gentler than that in the other examples. The nano-SiO2 modified UP asphalt is a thermosetting asphalt material, and has strong water permeability resistance and interlayer bonding force; common asphalt (matrix asphalt and SBS modified asphalt) belongs to thermoplastic asphalt materials, and has strong water permeability resistance and interlayer bonding force at normal temperature; SBS modified emulsified asphalt and SBR modified emulsified asphalt belong to emulsified asphalt materials, interlayer binding force is formed after water is evaporated after demulsification, and the binding strength is reduced rapidly under the soaking of water. At different temperatures, 40 ℃ compared to 20 ℃, the shear strength of the five bond materials decreased more rapidly, and the residual shear strength ratio curves were more inclined. This indicates that the water and temperature coupling effect at higher temperature is likely to cause the decrease of the adhesive strength of the adhesive layer material. In conclusion, the nano-SiO2 modified UP asphalt has better water immersion resistance (example 3) than other asphalt bonding layer materials.

4. Test for Freeze thaw resistance

Referring to road engineering asphalt and asphalt mixture test procedure JTG E20-2011, core samples of six binding materials are subjected to one, two and three freeze-thaw cycles (soaking in a water bath at 20 ℃ for 8 hours, then freezing at-10 ℃ for 8 hours, and then soaking in a water bath at 20 ℃ for 8 hours), and then subjected to a shear test, and test results are shown in Table 7.

TABLE 7

As can be seen from Table 7: with the increase of the number of freeze-thaw cycles, the shear strength of the five waterproof bonding materials is reduced in different degrees, and the reduction curve of the residual shear strength ratio of the embodiment 3 is much gentler than that of the other embodiments. This trend is similar to the test results of shear test after soaking, so nano-SiO2 modified UP asphalt has the best performance of freeze-thaw cycle resistance.

5. Fatigue resistance test

The fatigue test is carried out by referring to road engineering asphalt and asphalt mixture test procedure JTG E20-2011, and the test results are shown in tables 8 and 9.

TABLE 8

TABLE 9

As can be seen from the fatigue test results in tables 8 and 9, the sequence of the fatigue life from small to large is: SBR modified emulsified asphalt, SBS modified emulsified asphalt, base asphalt, SBS modified asphalt and nano-SiO₂Modified UP asphalt. This shows that the hot asphalt (base asphalt, SBS modified asphalt) has better bonding effect than the emulsified asphalt (SBR modified emulsified asphalt, SBS modified emulsified asphalt), and the resin asphalt (nano-SiO)₂The modified UP asphalt) has better bonding effect compared with hot asphalt (matrix asphalt and SBS modified asphalt), so that the cement concrete beam and the asphalt pavement layer are bonded into a whole better, and the fatigue life of the whole is prolonged.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that: any person skilled in the art can modify or easily conceive the technical solutions described in the foregoing embodiments or equivalent substitutes for some technical features within the technical scope of the present disclosure; such modifications, changes or substitutions do not depart from the spirit and scope of the embodiments of the present invention, and they should be construed as being included therein. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The bridge deck waterproof bonding layer material based on the photocatalyst is characterized by comprising a component A and a component B, wherein the component A comprises the following components in parts by weight: the component B is 1: 2.0-1: 2.9; wherein:

the component B comprises asphalt and a compatilizer;

in the component A, the weight ratio of unsaturated polyester resin: nano-SiO₂: photoinitiator (2): coupling agent 100:3:4: 3; in the component B, asphalt: compatibilizer 100: 4;

the asphalt is SBS modified asphalt, the penetration degree is 85.7, the softening point is 47.2, the dynamic viscosity is 156.8, and the ductility is more than 100.

2. The photocatalyst-based bridge deck water-proofing bonding layer material according to claim 1, wherein said unsaturated polyester resin is bisphenol A type unsaturated polyester resin and its solid content is 57.0% -63.0%.

3. A photocatalyst-based bridge deck water-repellent bond coat material as claimed in claim 1, wherein said photoinitiator is Omnirad 819.

4. A photocatalyst-based bridge deck waterproofing bonding layer material according to claim 1, wherein said nano-SiO is₂Is A type nano-SiO₂The silica content was 98.5%.

5. The photocatalyst-based bridge deck waterproofing adhesive layer material according to claim 1, wherein said coupling agent is a KH-570 silane coupling agent.

6. A photocatalyst-based bridge deck water-repellent bonding layer material according to claim 1, wherein said compatibilizer is maleic anhydride with a solids content > 99.5%.

7. A method for preparing a photocatalyst-based bridge deck waterproofing bonding layer material according to any one of claims 1 to 6, comprising the steps of:

step two: carrying out surface organic modification on the nano-SiO obtained in the step one₂Uniformly mixing the photoinitiator and the unsaturated polyester resin to obtain a component A;

8. The method for preparing a photocatalyst-based bridge deck waterproofing adhesive layer material according to claim 7, wherein nano-SiO is added before said first step₂Pretreating for 40-60 min under the conditions of alcohol-water solution, 100 ℃ and pH value of 4; in the alcohol-water solution, the volume ratio of ethanol to water is 10: 1.