A water-reactive asphalt cold patch material, its preparation method and usage method

Abstract

The present invention discloses a water-reactive asphalt cold patch material, its preparation method and usage method. The water-reactive asphalt cold patch material of the present invention comprises the following components in parts by mass: aggregate: 1000 parts; mineral powder: 50 to 60 parts; emulsified asphalt: 85 to 150 parts; demulsifier: 15 to 30 parts; superabsorbent resin: 1 to 10 parts. The preparation method of the water-reactive asphalt cold patch material of the present invention comprises the following steps: 1) adding the aggregate into a stirring pot and stirring evenly; 2) adding the emulsified asphalt into the stirring pot and stirring evenly; 3) adding the mineral powder and the demulsifier into the stirring pot and stirring evenly; 4) adding the superabsorbent resin into the stirring pot and stirring evenly. The water-reactive asphalt cold patch material of the present invention has the advantages of simple storage, convenient construction, fast early strength development, good bonding performance with the original road surface, strong water damage resistance, environmental friendliness, etc., and is suitable for large-scale popularization and application.

Description

Technical Field

[0001] The present invention relates to the technical field of road maintenance, and particularly relates to a water-reactive asphalt cold patch material, a preparation method thereof, and a using method thereof. Background Art

[0002] An asphalt pavement refers to various types of pavements paved by incorporating road-use asphalt materials into mineral materials. It has the advantages of comfortable driving, low frictional noise between tires and the road surface, and relatively high strength, and has been widely applied. However, under the combined action of natural factors and traffic loads, potholes are likely to appear on the asphalt pavement. The appearance of potholes not only affects driving comfort but also driving safety. At present, the methods for repairing potholes on asphalt pavements are divided into two types: hot patching and cold patching. The hot patching method has high requirements for construction environment and construction equipment and is not suitable for the rapid repair of small potholes. The cold patching method is to prefabricate asphalt cold patch materials in advance, store them sealed and dry, and then transport them to the construction site for simple stirring and paving after adding water when needed. It can quickly repair potholes and restore traffic, and has better practical application prospects compared with the hot patching method. However, the existing asphalt cold patch materials have problems such as difficult storage, high construction requirements, slow formation of early strength, poor bonding performance with the original road surface, poor water damage resistance, and easy occurrence of secondary damage, and it is still difficult to fully meet the actual application requirements.

[0003] Therefore, it is of great significance to develop an asphalt cold patch material with simple storage, convenient construction, fast development of early strength, good bonding performance with the original road surface, and strong water damage resistance. Summary of the Invention

[0004] The purpose of the present invention is to provide a water-reactive asphalt cold patch material, a preparation method thereof, and a using method thereof.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A water-reactive asphalt cold patch material, which comprises the following components in parts by mass:

[0007] Aggregate: 1000 parts;

[0008] Mineral powder: 50 parts to 60 parts;

[0009] Emulsified asphalt: 85 parts to 150 parts;

[0010] Demulsifier: 15 parts to 30 parts;

[0011] Superabsorbent resin: 1 part to 10 parts.

[0012] Preferably, the aggregate comprises the following components in mass percentage:

[0013] Aggregates with a particle size of 10 mm to 15 mm: 19% to 28%;

[0014] Aggregates with a particle size of 5 mm to 10 mm: 35% to 43%;

[0015] Aggregates with a particle size of 3 mm to 5 mm: 11% to 18%;

[0016] Aggregates with a particle size less than 3 mm: 16% to 26%. Aggregates of different particle sizes are graded according to a specific ratio, which can make the water-reactive asphalt cold patch material have a stable dense aggregate structure.

[0017] Preferably, the mineral powder is limestone mineral powder with a mesh size of 500 to 600.

[0018] Preferably, the emulsified asphalt has an elastic recovery ≥ 93% at 25°C, a complex shear modulus ≥ 10 kPa at 60°C, a dynamic viscosity ≥ 38500 Pa·s at 60°C, a rutting factor (G ＊ / sinδ) ≥ 2.5 kPa at 5°C, an elongation ≥ 30 cm at 5°C, and an evaporation residue content ≥ 60.5% of the emulsified asphalt. The emulsified asphalt has good normal-temperature fluidity and does not require heating of the asphalt during the production process of the water-reactive asphalt cold patch material, which can reduce energy consumption and the production method is more environmentally friendly.

[0019] Preferably, the emulsified asphalt is cationic emulsified asphalt.

[0020] Preferably, the demulsifier is calcium oxide powder with a mesh size of 190 to 210. The demulsifier can consume the water in the emulsified asphalt system, thereby avoiding the reaction between the superabsorbent resin and water in the water-reactive asphalt cold patch material before it is put into use, and avoiding affecting the workability of the water-reactive asphalt cold patch material during construction.

[0021] Preferably, the superabsorbent resin is polyacrylate with a number-average molecular weight of 1,000 to 8,000. The superabsorbent resin is a functional polymer material with a three-dimensional network structure. There are a large number of strong water-absorbing groups such as carboxyl, hydroxyl, sulfonic, and amide groups on the molecular chain. When in contact with water, external free water molecules diffuse into the resin polymer network to form hydrated polymer chains, enabling the water absorption capacity to reach several hundred times or even thousands of times its own weight. The resin macromolecular chains are connected by hydrogen bonds to form a three-dimensional network structure, which can effectively lock water. The high-concentration ionic groups inside it cause an osmotic pressure pointing inward between the system and the outside environment, so that water in the environment diffuses into the system and is locked. Based on the functional characteristics of the superabsorbent resin, its water absorption process includes chemical adsorption and physical adsorption. Chemical adsorption refers to the hydrophilic groups on the superabsorbent resin molecular chain combining with water molecules through chemical bonds to form a whole. When the water-reactive asphalt cold patch material repairs potholes, the superabsorbent resin undergoes a curing reaction with water to form strength, thus meeting the road use requirements and enabling rapid traffic.

[0022] A preparation method of the water-reactive asphalt cold patch material as described above includes the following steps:

[0023] 1) Add the aggregate to the mixing pot and mix evenly;

[0024] 2) Add the emulsified asphalt to the mixing pot and mix evenly;

[0025] 3) Add the mineral powder and the demulsifier to the mixing pot and mix evenly;

[0026] 4) Add the superabsorbent resin to the mixing pot and mix evenly to obtain the water-reactive asphalt cold patch material.

[0027] Preferably, the mixing time in step 1) is 20 s to 40 s.

[0028] Preferably, the mixing time in step 2) is 40 s to 50 s.

[0029] Preferably, the mixing time in step 3) is 20 s to 35 s.

[0030] Preferably, the mixing time in step 4) is 20 s to 30 s.

[0031] Preferably, the total mixing time in steps 1) to 4) ≤ 180 s.

[0032] A use method of the water-reactive asphalt cold patch material as described above includes the following steps: Add water to the water-reactive asphalt cold patch material, mix for another 10 s to 25 s, and then fill the potholes in the asphalt pavement.

[0033] Preferably, the mass ratio of the water-reactive asphalt cold patch material to water is 1:0.01 to 0.21.

[0034] The beneficial effects of the present invention are as follows: The water-reactive asphalt cold patch material of the present invention has the advantages of simple storage, convenient construction, fast early strength development, good bonding performance with the original road surface, strong water damage resistance, environmental friendliness, etc., and is suitable for large-scale popularization and application.

[0035] Specifically:

[0036] 1) The water-reactive asphalt cold patch material of the present invention overcomes the technical problems existing in traditional asphalt cold patch materials, such as difficult storage, slow early strength formation, poor bonding performance with the original road surface, easy to cause secondary damage, difficult mixing of various additives at the construction site, and high construction technical requirements. Its storage performance is stable, early strength is improved quickly, bonding performance with the original road surface is good, production process is simple, road use performance is good, and it is environmentally friendly, fully meeting the requirements of simple use and quick traffic opening of asphalt cold patch materials;

[0037] 2) The water-reactive asphalt cold patch material of the present invention is in a loose state at normal temperature, convenient for storage. When in use, by adding water and reacting with the superabsorbent resin, early strength can be quickly formed, which is beneficial for quick traffic opening. Specific Embodiments

[0038] The present invention will be further explained and described below in conjunction with specific embodiments.

[0039] Example 1:

[0040] A water-reactive asphalt cold patch material has the following composition as shown in the table below:

[0041] Table 1 Composition Table of a Water-Reactive Asphalt Cold Patch Material

[0042]

[0043]

[0044] The preparation method of the above water-reactive asphalt cold patch material is as follows:

[0045] 1) Add the aggregate to the mixing pot and stir for 40 s;

[0046] 2) Add the cationic emulsified asphalt to the mixing pot and stir for 45 s;

[0047] 3) Add the limestone powder and calcium oxide powder to the mixing pot and stir for 35 s;

[0048] 4) Add the polyacrylate to the mixing pot and stir for 25 s to obtain the water-reactive asphalt cold patch material.

[0049] Example 2:

[0050] A water-reactive asphalt cold patch material has the following composition as shown in the table below:

[0051] Table 2 Composition Table of a Water-Reactive Asphalt Cold Patch Material

[0052]

[0053]

[0054] The preparation method of the above water-reactive asphalt cold patch material is as follows:

[0055] 1) Add the aggregate to the mixing pot and mix for 40 s;

[0056] 2) Add the cationic emulsified asphalt to the mixing pot and mix for 45 s;

[0057] 3) Add the limestone powder and calcium oxide powder to the mixing pot and mix for 35 s;

[0058] 4) Add the polyacrylate to the mixing pot and mix for 25 s to obtain the water-reactive asphalt cold patch material.

[0059] Example 3:

[0060] A water-reactive asphalt cold patch material, the composition of which is shown in the following table:

[0061] Table 3 Composition Table of a Water-Reactive Asphalt Cold Patch Material

[0062]

[0063] The preparation method of the above water-reactive asphalt cold patch material is as follows:

[0064] 1) Add the aggregate to the mixing pot and mix for 40 s;

[0065] 2) Add the cationic emulsified asphalt to the mixing pot and mix for 45 s;

[0066] 3) Add the limestone powder and calcium oxide powder to the mixing pot and mix for 35 s;

[0067] 4) Add the polyacrylate to the mixing pot and mix for 25 s to obtain the water-reactive asphalt cold patch material.

[0068] Example 4:

[0069] A water-reactive asphalt cold patch material, the composition of which is shown in the following table:

[0070] Table 4 Composition Table of a Water-Reactive Asphalt Cold Patch Material

[0071]

[0072] The preparation method of the above water-reactive asphalt cold patch material is as follows:

[0073] 1) Add the aggregate to the mixing pan and mix for 40 s;

[0074] 2) Add the cationic emulsified asphalt to the mixing pan and mix for 45 s;

[0075] 3) Add the limestone powder and calcium oxide powder to the mixing pan and mix for 35 s;

[0076] 4) Add the polyacrylate to the mixing pan and mix for 25 s to obtain the water-reactive asphalt cold patch material.

[0077] Example 5:

[0078] A water-reactive asphalt cold patch material has the following composition as shown in the table below:

[0079] Table 5 Composition table of a water-reactive asphalt cold patch material

[0080]

[0081] The preparation method of the above water-reactive asphalt cold patch material is as follows:

[0082] 1) Add the aggregate to the mixing pan and mix for 40 s;

[0083] 2) Add the cationic emulsified asphalt to the mixing pan and mix for 45 s;

[0084] 3) Add the limestone powder and calcium oxide powder to the mixing pan and mix for 35 s;

[0085] 4) Add the polyacrylate to the mixing pan and mix for 25 s to obtain the water-reactive asphalt cold patch material.

[0086] Example 6:

[0087] A water-reactive asphalt cold patch material has the following composition as shown in the table below:

[0088] Table 6 Composition table of a water-reactive asphalt cold patch material

[0089]

[0090]

[0091] The preparation method of the above water-reactive asphalt cold patch material is as follows:

[0092] 1) Add the aggregate to the mixing pan and mix for 40 s;

[0093] 2) Add the cationic emulsified asphalt to the mixing pan and mix for 45 s;

[0094] 3) Add the limestone powder and calcium oxide powder to the mixing pan and mix for 35 s;

[0095] 4) Add polyacrylate into the stirring pot and stir for 25 s to obtain the water-reactive asphalt cold patch material.

[0096] Example 7:

[0097] A water-reactive asphalt cold patch material has the following composition as shown in the table below:

[0098] Table 7 Composition table of a water-reactive asphalt cold patch material

[0099]

[0100]

[0101] The preparation method of the above water-reactive asphalt cold patch material is as follows:

[0102] 1) Add the aggregate into the stirring pot and stir for 40 s;

[0103] 2) Add the cationic emulsified asphalt into the stirring pot and stir for 45 s;

[0104] 3) Add the limestone powder and calcium oxide powder into the stirring pot and stir for 35 s;

[0105] 4) Add polyacrylate into the stirring pot and stir for 25 s to obtain the water-reactive asphalt cold patch material. Comparative example:

[0106] An asphalt cold patch material has the following composition as shown in the table below:

[0107] Table 8 Composition table of an asphalt cold patch material

[0108]

[0109]

[0110] The preparation method of the above asphalt cold patch material is as follows:

[0111] 1) Add the aggregate into the stirring pot and stir for 40 s;

[0112] 2) Add the cationic emulsified asphalt into the stirring pot and stir for 45 s;

[0113] 3) Add the limestone powder and calcium oxide powder into the stirring pot and stir for 35 s to obtain the asphalt cold patch material.

[0114] Performance test:

[0115] The performance test results of the water-reactive asphalt cold patch materials of Examples 1 to 7 and the asphalt cold patch material of the comparative example are as shown in the table below:

[0116] Table 9 Performance test results of the water-reactive asphalt cold patch materials of Examples 1 to 7 and the asphalt cold patch material of the comparative example

[0117]

[0118] Note:

[0119] The water-reactive asphalt cold patch materials of Examples 1 to 7 were mixed with water and stirred for 20 s (using the reaction of polyacrylate with water to form strength) to prepare asphalt cold patch material test samples (the mass ratios of the water-reactive asphalt cold patch materials of Examples 1 to 7 to water were 1231:20, 1231:20, 1157:40, 1159:96, 1236:120, 1178:160, and 1190:240 in sequence; the asphalt cold patch material of the comparative example did not add polyacrylate and did not need to add water), and then the adhesion grade, penetration strength, Marshall stability, residual stability, water stripping resistance, cohesiveness, and splitting tensile strength were tested.

[0120] Adhesion grade: The test was carried out with reference to "JT / T 972-2015 Cold Patch Finished Materials for Asphalt Pavement Potholes".

[0121] Penetration strength: The test was carried out with reference to "JT / T 972-2015 Cold Patch Finished Materials for Asphalt Pavement Potholes".

[0122] Marshall stability: The test was carried out with reference to "JT T972-2015 Cold Patch Finished Materials for Asphalt Pavement Potholes" as follows:

[0123] a) Initial Marshall stability: The asphalt cold patch material test sample was formed into a Marshall specimen at normal temperature by the method of double-sided compaction 50 times at one time. The specimen met 63.5 mm ± 1.3 mm. After demolding, the Marshall stability was directly measured (without water bath) to simulate the outdoor repair process;

[0124] b) Formed Marshall stability: The asphalt cold patch material test sample was loaded into a Marshall test mold, double-sided compacted 25 times, and cured in an oven set at 110 °C for 24 h together with the test mold. After taking out, it was double-sided compacted 25 times again to make a Marshall specimen. The specimen met 63.5 mm ± 1.3 mm. After demolding, it was cured in a constant temperature water bath at 25 °C for 60 min, and then the Marshall stability test was carried out.

[0125] Residual stability: The test was carried out with reference to "JT T972-2015 Cold Patch Finished Materials for Asphalt Pavement Potholes" as follows: Two groups of specimens were made from the asphalt cold patch material. One group was placed in a constant temperature water bath at 60 °C for 30 min, and then taken out to measure its Marshall stability MS1. The other group was placed in a constant temperature water bath at 60 °C for 48 h, and then taken out to measure its Marshall stability MS2. Then the residual stability MS0 was calculated. The calculation formula for the residual stability was: MS0 (%) = MS2 / MS1 × 100%.

[0126] Water content: Test according to the "Technical Specifications for Construction of Highway Asphalt Pavements (JTJ F40 - 2004)".

[0127] Water resistance to stripping: Test according to the "Technical Specifications for Construction of Highway Asphalt Pavements (JTJ F40 - 2004)".

[0128] Cohesiveness: Test according to the "Technical Specifications for Construction of Highway Asphalt Pavements (JTJ F40 - 2004)".

[0129] Splitting tensile strength: Test according to the "Cold Patch Finished Material for Potholes in Asphalt Pavements (JT / T 972 - 2015)", specifically as follows:

[0130] a) Initial splitting tensile strength: Compaction is carried out using the same preparation method as the initial stability of Marshall specimens. After demolding, directly measure the splitting tensile strength of the specimens (without water bath);

[0131] b) Formed splitting tensile strength: Load the test sample of asphalt cold patch material into the Marshall test mold, compact it 25 times on both sides, cure it in an oven set at 110°C for 24 hours together with the test mold, take it out and then compact it 25 times on both sides to make a Marshall specimen. The specimen should meet 63.5mm ± 1.3mm. After demolding, keep it in a constant temperature water bath at 15°C ± 0.5°C for 1.5 hours, and measure the formed splitting tensile strength under the condition of a loading rate of 50mm / min.

[0132] As can be seen from Table 9:

[0133] a) Compared with the asphalt cold patch material of the comparative example, for the water - reactive asphalt cold patch materials of Examples 1 - 7, due to the incorporation of a certain amount of polyacrylate (superabsorbent resin), the various properties of the asphalt cold patch material have been improved to varying degrees. This is because the polyacrylate undergoes a curing reaction with water, enhancing the bonding effect between different materials. Therefore, the water - reactive asphalt cold patch material containing superabsorbent resin of the present invention has obvious performance advantages;

[0134] b) The initial Marshall stability of the water - reactive asphalt cold patch materials of Examples 1 - 7 is greater than 2kN, meeting the requirement for the rapid opening to traffic of the asphalt cold patch material after repair. And as the content of polyacrylate increases, the initial Marshall stability of the water - reactive asphalt cold patch material first increases and then decreases;

[0135] c) The formed Marshall stability of the water - reactive asphalt cold patch materials of Examples 1 - 7 is above 4.5kN, meeting the strength requirement of the asphalt cold patch material after forming. And as the content of polyacrylate increases, the formed Marshall stability of the water - reactive asphalt cold patch material first increases and then decreases;

[0136] d) The initial splitting tensile strength of the water-reactive asphalt cold patch materials in Examples 1 to 7 is ≥0.3 MPa, which can withstand the traffic load after repair and meet the requirement of rapid traffic opening.

[0137] e) Compared with the initial splitting tensile strength, the formed splitting strength of the asphalt cold patch materials incorporated with the same dosage of polyacrylate has been improved to varying degrees, and all are greater than 0.4 MPa, which can withstand the traffic load after repair.

[0138] f) The water-reactive asphalt cold patch material in Example 3 has the best performance (key indexes such as Marshall stability, splitting strength, and penetration strength are all relatively high), and the amount of emulsified asphalt added is small and the content of polyacrylate incorporated is moderate, which is beneficial to cost saving.

[0139] The above embodiments are the preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A water-reactive asphalt cold patch material, characterized in that, Comprising the following components in parts by mass: Aggregates: 1000 parts; Mineral powder: 50 - 60 parts; Emulsified asphalt: 85 - 150 parts; Demulsifier: 15 - 30 parts; Superabsorbent resin: 1 - 10 parts; The aggregates comprise the following components in mass percentages: Aggregates with a particle size of 10 mm - 15 mm: 19% - 28%; Aggregates with a particle size of 5 mm - 10 mm: 35% - 43%; Aggregates with a particle size of 3 mm - 5 mm: 11% - 18%; Aggregates with a particle size less than 3 mm: 16% - 26%; The mineral powder is limestone mineral powder with a mesh size of 500 - 600; The emulsified asphalt is emulsified asphalt with an elastic recovery of ≥93% at 25°C, a complex shear modulus of ≥10 kPa at 60°C, a dynamic viscosity of ≥38500 Pa·s at 60°C, a rutting factor of the evaporation residue of ≥2.5 kPa, a ductility of ≥30 cm at 5°C, and an evaporation residue content of ≥60.5%; The demulsifier is calcium oxide powder with a mesh size of 190 - 210; The superabsorbent resin is polyacrylate with a number average molecular weight of 1000 - 8000; The water - reactive asphalt cold patch material is prepared by a preparation method including the following steps: 1) Add the aggregates to the mixing pan and mix evenly; 2) Add the emulsified asphalt to the mixing pan and mix evenly; 3) Add the mineral powder and the demulsifier to the mixing pan and mix evenly; 4) Add the superabsorbent resin to the mixing pan and mix evenly to obtain the water - reactive asphalt cold patch material; When in use, add water to the water - reactive asphalt cold patch material, stir for 10 s - 25 s, and then fill the potholes in the asphalt pavement; The mass ratio of the water - reactive asphalt cold patch material to water is 1:0.01 - 0.

21.

2. The water-reactive asphalt cold patch material according to claim 1, characterized in that: The mixing time in step 1) is 20 s - 40 s; the mixing time in step 2) is 40 s - 50 s; the mixing time in step 3) is 20 s - 35 s; the mixing time in step 4) is 20 s - 30 s; the total mixing time in steps 1) - 4) ≤180 s.

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