Cold patch asphalt mixture based on dearomatization solvent oil and preparation method thereof

Abstract

The invention discloses a cold patch asphalt mixture based on dearomatization solvent oil and a preparation method thereof, the cold patch asphalt mixture comprises the following substances in percentage by mass: 89-91 wt% of aggregate, 2-3 wt% of mineral powder, 2-3 wt% of cement, 0.4-0.6 wt% of bentonite and 4-6 wt% of asphalt cold patch liquid, and D60 dearomatization solvent oil is used as a diluent in the asphalt cold patch liquid. The preparation method comprises the following steps: preparing asphalt cold supplementing liquid, and preserving heat for later use; drying the aggregate, the mineral powder, the cement and the bentonite, and preserving heat for later use; the mixing pot is heated, and the aggregate, the cement and the bentonite are put into the mixing pot to be stirred; adding the asphalt cold supplementing liquid into the mixing pot for stirring; and adding the mineral powder into the mixing pot, and stirring to obtain the cold patch asphalt mixture based on the dearomatization solvent oil. The cold patch asphalt mixture prepared by the invention has excellent comprehensive performance, perfectly meets the performance requirement of a hot mix asphalt mixture, can quickly form strength, can quickly open traffic after repairing pits and slots, and has small influence on road traffic.

Description

Technical Field

[0001] The invention belongs to the technical field of road engineering and environmental protection, and in particular relates to a cold patch asphalt mixture based on dearomatized solvent oil and a preparation method thereof. Background Art

[0002] With the continuous growth of my country's economic construction, higher requirements will be placed on the quality, performance, maintenance and transportation efficiency of highway construction in the future.

[0003] Potholes are one of the main diseases of asphalt pavements of all grades of highways. They refer to bowl-shaped holes of varying sizes and steep edges on the surface of the pavement. They not only affect the performance and driving comfort of the asphalt pavement, but also shorten the service life of the asphalt pavement. At present, the main methods for repairing potholes are hot patching, warm patching, hot regeneration and cold patching. The application technology of hot patching is relatively mature and has good treatment effects. It is especially suitable for pothole repairs with large engineering volumes. However, hot patching is greatly affected by weather and temperature. During the repair process, a high construction temperature needs to be maintained. The repair process is complicated and is mostly used to repair potholes in summer. In addition, the smoke generated during the repair process will pollute the environment and harm the health of workers. The warm patching method and hot regeneration method have high requirements for new materials, new processes and new equipment. The application technology is not yet mature and is still in the research and development stage. Compared with the above three repair methods, the cold patch method uses cold patch materials. The advantages of cold patch materials in environmental adaptability, repair procedures, material storage and transportation are far greater than those of hot patch materials. In addition, the construction process of the cold patch method is simple and can be constructed all day long. It is not affected by temperature and weather, does not produce high-temperature toxic gases, and is energy-saving and environmentally friendly. Therefore, the cold patch method has become the preferred method for pothole repair.

[0004] The cold patch material used in the cold patch method is also known as cold patch asphalt mixture, which refers to an asphalt mixture that can be mixed and constructed at room temperature or medium and low temperature. At present, cold patch materials mainly include three types: emulsified cold patch material, reactive cold patch material and solvent cold patch material. Emulsified cold patch material, also known as emulsified asphalt cold patch material, is to add an emulsifier to the base asphalt so that it is distributed in the water and flows in the form of tiny particles. Its strength formation mainly depends on the release of asphalt after demulsification. The initial strength of this cold patch material after construction is relatively low, and it takes a period of traffic compaction and demulsification curing to achieve a higher strength. However, there is currently no mature technology that can completely control the demulsification of emulsified asphalt, which makes it impossible to guarantee the storage stability of the cold patch material and the open time after construction. Reactive cold patch material is a resin and a curing agent that can undergo a curing reaction in a short time after mixing, and quickly form strength. However, the current cost of the resin is relatively high, and this cold patch material cannot be widely used. Solvent-based cold patch material, also known as diluted asphalt cold patch material, is a material that adds a volatile diluent to the base asphalt to reduce the viscosity. Its strength formation mainly depends on the recovery of asphalt viscosity after the diluent evaporates, and is greatly affected by the type of diluent and natural environmental factors. At present, the most commonly used diluents are light gasoline and No. 0 diesel, but these substances not only pollute the environment, but are also difficult to evaporate completely, resulting in an unsatisfactory life of the cold patch material. Due to the short service life of the cold patch material, the same pothole will face the problem of potholes appearing again after repair. Therefore, it is urgent to develop a cold patch asphalt mixture based on dearomatized solvent oil and a preparation method thereof, in order to explore an alternative solvent with good solubility for asphalt, a suitable volatilization rate, and environmental protection, so that the prepared cold patch asphalt mixture has a longer service life, can quickly form strength, and the final performance can meet the requirements of hot mix asphalt mixture.

[0005] The invention patent with application publication number CN103043962A discloses a mixture for repairing potholes at room temperature on asphalt pavement, and its preparation method and application. The mixture includes, by mass percentage, 5-7% asphalt liquid, 84.5-90% stone, and 0.1-0.5% waste rubber powder, wherein the asphalt liquid includes, by mass percentage, 70-80% modified asphalt, 20-80% diluent, or 52-66% ordinary asphalt, 4-8% polymer, and 30-40% diluent, and the stone is made of 0.075-13.2mm stone mixed according to a certain gradation, and the diluent is selected from one or more of No. 6 solvent oil, No. 120 solvent oil, and No. 200 solvent oil. The technical problem to be solved by this technical solution is how to make the potholes after repair not loose and not peeling, but there is no record on how to increase the time for the cold patch material to form strength, and the final performance of the repair mixture needs to be improved.

[0006] The invention patent with application publication number CN105348827A discloses a solvent-based cold patch asphalt liquid and its preparation process. The cold patch asphalt liquid includes the following substances by weight: 100 parts of petroleum asphalt, 10-15 parts of diluent, 10-15 parts of heavy oil, 10-15 parts of solvent oil, 1-5 parts of tackifier, 1-5 parts of reinforcing agent, 0.2-0.8 parts of surfactant, 0.5-0.8 parts of anti-stripping agent, the diluent is 10# diesel, 0# diesel, -10# diesel or aviation kerosene, and the solvent oil is C1-C 10 A kind of aromatic solvent oil. The technical problem to be solved by this technical solution is how to improve the initial strength and molding strength of cold patch asphalt mixture, but from the test data of the embodiment, the initial strength and molding strength are relatively low, especially the initial strength is only about 2.1KN, which means that the cold patch asphalt mixture takes a long time to form strength, which is not conducive to the repair of potholes on highways. Summary of the invention

[0007] In order to solve the problems existing in the prior art, the present invention provides a cold patch asphalt mixture based on dearomatized solvent oil, wherein the mass percentage of each substance in the cold patch asphalt mixture is as follows: aggregate accounts for 89-91wt%, mineral powder accounts for 2-3wt%, cement accounts for 2-3wt%, bentonite accounts for 0.4-0.6wt%, asphalt cold patch liquid accounts for 4-6wt%, and the ratio of the mass of the asphalt cold patch liquid to the sum of the mass of the aggregate and the mineral powder is 0.05-0.06:1; D60 dearomatized solvent oil is used as a diluent in the asphalt cold patch liquid.

[0008] Preferably, the aggregate includes nine particle sizes, and the mass percentage of each particle size in the aggregate is: 2-5wt% for particle size 13.2-16mm, 15-20wt% for particle size 9.5-13.2mm, 25-35wt% for particle size 4.75-9.5mm, 15-25wt% for particle size 2.36-4.75mm, 10-15wt% for particle size 1.18-2.36mm, 5-8wt% for particle size 0.6-1.18mm, 5-8wt% for particle size 0.3-0.6mm, 1-3wt% for particle size 0.15-0.3mm, and 1-3wt% for particle size 0.075-0.15mm. The aggregate is limestone and / or granite; the particle size of the mineral powder is less than 0.075mm, and the mineral powder is limestone.

[0009] In any of the above schemes, it is preferred that the cement is any one or more of silicate cement, aluminate cement, sulphoaluminate cement and ferroaluminate cement; and the bentonite is any one or more of sodium-based bentonite, calcium-based bentonite and magnesium-based bentonite.

[0010] In any of the above schemes, it is preferred that the mass percentages of the substances in the asphalt cold repair liquid are as follows: base asphalt accounts for 68-75wt%, modifier accounts for 2.2-3.4wt%, anti-stripping agent accounts for 0.2-0.8wt%, and diluent accounts for 22-29wt%.

[0011] In any of the above schemes, it is preferred that the amount of the diluent added increases with the amount of the modifier added, and within the mass percentage range of the modifier and the diluent, when the amount of the modifier added increases by 0.2wt%, the amount of the diluent added increases by 1-1.5wt% accordingly.

[0012] In any of the above schemes, it is preferred that the base asphalt is No. 70 base asphalt or No. 90 base asphalt; the modifier is SBS modifier or SBR modifier; the anti-stripping agent is a non-amine anti-stripping agent, and the non-amine anti-stripping agent is any one or more of polyphosphoric acid, phosphate ester, and nitrogen-containing complex; the diluent is D60 dearomatized solvent oil, and the D60 dearomatized solvent oil is made from straight-run distillate oil, hydrocracking distillate oil or low-sulfur straight-run jet fuel as raw materials, and is fractionated after deep desulfurization, dearomatization, and hydrogenation refining, with a distillation range of 180-230°C, a closed cup flash point of 60-70°C, an aromatic content of less than 0.03wt%, a sulfur content of less than 0.2mg / kg, and a saturated hydrocarbon content of more than 99.9%.

[0013] The present invention also provides a method for preparing a cold patch asphalt mixture based on dearomatized solvent oil, which is used to prepare any of the cold patch asphalt mixtures based on dearomatized solvent oil described above, and comprises the following steps in chronological order:

[0014] Step 1: Prepare asphalt cold make-up liquid according to the design requirements, and put the prepared asphalt cold make-up liquid into an oven for heat preservation and standby use;

[0015] Step 2: Weigh aggregate, mineral powder, cement, bentonite, and asphalt cold make-up liquid according to design requirements for use;

[0016] Step 3: putting the aggregate, mineral powder, cement and bentonite into an oven for drying. After the drying is completed, lowering the temperature in the oven to a certain temperature so that the aggregate, mineral powder, cement and bentonite are kept warm at the lowered temperature for later use;

[0017] Step 4: Heat the mixing pot to a certain temperature, then put the aggregate, cement and bentonite kept warm in the oven into the mixing pot and stir them with a stirrer;

[0018] Step 5: Keep the temperature of the mixing pot unchanged, add the asphalt cold make-up liquid kept warm in the oven into the mixing pot, and stir with a stirrer;

[0019] Step 6: Keep the temperature of the mixing pot unchanged, add the mineral powder kept warm in the oven into the mixing pot, and stir it with a stirrer to obtain a cold patch asphalt mixture based on dearomatized solvent oil.

[0020] Preferably, in step 1, the method for preparing the asphalt cold replenishment fluid comprises the following steps in order:

[0021] Step (1): weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements and set aside;

[0022] Step (2): placing the matrix asphalt in a container, and then placing the container containing the matrix asphalt in an oven for heating at a temperature of 100-120° C. for a heating time of 1-2 h;

[0023] Step (3): After the heating is completed, take out the container containing the base asphalt from the oven, add the modifier into the container, and then place the container containing the base asphalt and the modifier on an induction cooker for heating, stirring while heating until the base asphalt and the modifier are completely blended, the heating temperature is raised to 160-170°C, and the heating time is 15-20 minutes;

[0024] Step (4): placing the container containing the base asphalt and the modifier into an oil bath, and using a high-speed shearing instrument to perform shearing and stirring to obtain modified asphalt, the temperature of the oil bath is 160-170° C., the shearing speed is 5000-6000 r / min, and the shearing and stirring time is 0.5-1 h;

[0025] Step (5): lower the temperature of the oil bath to a certain temperature, then use a stirrer to add the diluent while stirring until the modified asphalt and the diluent are completely mixed, lower the temperature of the oil bath to 100-120°C, and stir for 15-20 minutes;

[0026] Step (6): Continue stirring with a stirrer while cooling down. After the temperature of the oil bath drops to a certain temperature, add the anti-stripping agent and stir until the anti-stripping agent is completely blended to obtain the asphalt cold fill liquid. The temperature of the oil bath drops to 60-80°C and the stirring time is 15-20 minutes.

[0027] In any of the above schemes, preferably, in step 1, another method for preparing the asphalt cold replenishment fluid comprises the following steps in chronological order:

[0028] Step A: weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements for use;

[0029] Step B: Put the matrix asphalt into a container, and then put the container containing the matrix asphalt into an oven for heating at a temperature of 100-120° C. for a heating time of 1-2 hours;

[0030] Step C: After the heating is completed, take out the container containing the matrix asphalt from the oven, add the diluent into the container, and then put the container containing the matrix asphalt and the diluent into an oil bath, and stir with a stirrer until the matrix asphalt and the diluent are completely melted. The temperature of the oil bath is 60-80°C, and the stirring time is 10-15 minutes;

[0031] Step D: Keep the temperature of the oil bath unchanged, continue stirring with an agitator, add the anti-stripping agent while stirring, until the anti-stripping agent is completely integrated, so as to obtain the diluted base asphalt, the temperature of the oil bath is 60-80°C, and the stirring time is 10-15min; Step E: Keep the temperature of the oil bath unchanged, continue stirring with an agitator, add the modifier while stirring, until the diluted base asphalt and the modifier are completely integrated, and then use a high-speed shear instrument for shear stirring to obtain the asphalt cold replenishment liquid, the temperature of the oil bath is 60-80°C, the stirring time is 20-25min, the shear speed is 5000-6000r / min, and the shear stirring time is 20-30min.

[0032] In any of the above schemes, it is preferred that in step one, the insulation temperature of the asphalt cold make-up liquid is 60-80°C; in step three, the drying temperature is 120-130°C, the drying time is 3-4h, and the temperature in the oven is reduced to 70-90°C, that is, the insulation temperature of the aggregate, mineral powder, cement, and bentonite is 70-90°C; in step four, the temperature of the mixing pot is heated to 60-80°C, and the stirring time is 90-120s; in step five, the temperature of the mixing pot is 60-80°C, and the stirring time is 90-120s; in step six, the temperature of the mixing pot is 60-80°C, and the stirring time is 90-120s.

[0033] The oven, induction cooker, mixing pot, oil bath pot, agitator, high-speed shearing instrument, etc. used in the present invention are all conventional equipment in the field, and no special requirements are made on the model and structure of the equipment. SBS is a styrene-butadiene-styrene block copolymer, and SBR is styrene-butadiene rubber. The aggregate includes nine particle sizes, namely, particle size 13.2-16mm, particle size 9.5-13.2mm, particle size 4.75-9.5mm, particle size 2.36-4.75mm, particle size 1.18-2.36mm, particle size 0.6-1.18mm, particle size 0.3-0.6mm, particle size 0.15-0.3mm, and particle size 0.075-0.15mm, i.e., 13.2mm≤particle size<16mm, 9.5mm≤particle size The particle size of the mineral powder is less than 0.075mm, that is, 0mm≤particle size<0.075mm. For each particle size, the material is passed through the upper and lower sieve holes in sequence to obtain a particle size between the upper and lower sieve holes, for example: the particle size is 1.18-2.36mm (1.18mm≤particle size<2.36mm), that is, the material is passed through the 2.36mm sieve hole and the 1.18mm sieve hole in sequence to obtain a particle size between 1.18-2.36mm.

[0034] In the whole preparation process of the asphalt cold patch fluid of the present invention, the selection of each substance in the asphalt cold patch fluid, the mass percentage of each substance, the order of addition of each substance, the process parameters of each step, etc. are very critical. At the same time, in the whole preparation process of the cold patch asphalt mixture, the selection of each substance in the cold patch asphalt mixture, the mass percentage of each substance, the order of addition of each substance, the process parameters of each step, etc. are also very critical. Only by synergizing the various formula parameters and process parameters can the expected technical effect of the present invention be achieved.

[0035] The present invention adopts D60 dearomatized solvent oil as a diluent, which is a first in the preparation technology of cold patch asphalt mixture and is also a key substance in the technical solution of the present invention. D60 dearomatized solvent oil is used as a diluent to replace diesel, light gasoline, aromatic solvent oil, etc. It is colorless, non-toxic, has very low odor, narrow fraction, strong solubility, good volatility, saturated hydrocarbon content greater than 99.9%, and has good oxidation stability while ensuring good solubility. At room temperature and natural ventilation conditions, D60 dearomatized solvent oil can be used normally without taking special safety and fire prevention measures, and its contact risk is very low. The production and construction process is safer and has minimal impact on the atmospheric environment and workers' health. D60 dearomatized solvent oil has a moderate evaporation rate and a more complete evaporation degree, which can ensure that the construction site has enough time for sufficient paving and compaction, forming a better combination with the original road surface. In addition, D60 dearomatized solvent oil has a minimal effect on the performance of asphalt cold patch materials. There is no need to use expensive resins and other materials. Only a small amount of anti-stripping agent is added to perfectly meet the performance requirements of hot-mix asphalt mixtures, and the production cost is low.

[0036] The cold patch asphalt mixture based on dearomatized solvent oil and the preparation method thereof of the present invention have the following beneficial effects:

[0037] (1) The D60 dearomatized solvent oil used in the present invention is a highly environmentally friendly, pollution-free excellent solvent, colorless, non-toxic, and has very little odor, which can provide workers with a good construction environment; at the same time, its saturated hydrocarbon content is greater than 99.9%, the aromatic hydrocarbon content is less than 0.03wt%, and the sulfur content is less than 0.2mg / kg, which has little impact on the environment; the closed cup flash point of D60 dearomatized solvent oil is 60-70℃, which is not a hazardous chemical and can be used in normal production without taking special fire prevention measures. The present invention selected 73 kinds of organic volatiles including benzene series, organic halides, aldehydes, ketones, alcohols, esters, alkanes, etc. for content detection, and the results showed that the contents of 12 kinds of organic volatiles detected were less than 500μg / ml.

[0038] (2) The present invention proposes for the first time to use D60 dearomatized solvent oil as a diluent, which perfectly replaces the diesel, light gasoline, aromatic solvent oil and other substances used in the traditional preparation of cold patch asphalt mixture; D60 dearomatized solvent oil has good solubility in asphalt, and the appropriate volatilization rate can not only meet the construction time requirements but also improve the early strength as soon as possible.

[0039] (3) The cold-patch asphalt mixture prepared by the present invention has excellent comprehensive performance and can perfectly meet the performance requirements of hot-mix asphalt mixture. The molding stability is higher than 8KN, the residual stability of the immersion Marshall test is greater than 80%, the residual strength ratio of the freeze-thaw splitting test is greater than 75%, and the dynamic stability of the rutting test is greater than 2800 times / mm, and has a longer service life.

[0040] (4) The cold patch asphalt mixture prepared by the present invention can quickly develop strength (characterized by the initial strength of the cold patch asphalt mixture), and traffic can be opened more quickly after the potholes are repaired, with little impact on road traffic.

[0041] (5) The cold patch asphalt mixture prepared by the present invention is more suitable for repairing potholes on expressways and first- and second-class highways in summer, and is also suitable for repairing potholes on first- and second-class highways in spring and autumn. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a flow chart of a preferred embodiment of a cold patch asphalt mixture based on dearomatized solvent oil and a preparation method thereof according to the present invention;

[0043] Figure 2 for Figure 1 Photographs of AR-I type anti-stripping agents used in the illustrated examples;

[0044] Figure 3 for Figure 1 Photograph of D60 dearomatized solvent naphtha used in the illustrated examples;

[0045] Figure 4 for Figure 1 Photos of asphalt cold dressing fluid prepared in the illustrated embodiment;

[0046] Figure 5 for Figure 1 Photograph of the cold patch asphalt mixture prepared in the illustrated embodiment. DETAILED DESCRIPTION

[0047] In order to further understand the content of the present invention, the present invention will be described in detail below in conjunction with specific embodiments.

[0048] Embodiment 1:

[0049] According to a preferred embodiment of the cold patch asphalt mixture based on dearomatized solvent oil of the present invention, the mass percentage of each substance in the cold patch asphalt mixture is 89wt% of aggregate, 2.6wt% of mineral powder, 3wt% of cement, 0.4wt% of bentonite, and 5wt% of asphalt cold patch liquid. The ratio of the sum of the masses of the cement and the bentonite to the mass of the asphalt cold patch liquid is 0.055:1, which is ensured to be within the range of 0.05-0.06:1; D60 dearomatized solvent oil is used as a diluent in the asphalt cold patch liquid.

[0050] The aggregate includes nine particle sizes, and the mass percentage of each particle size in the aggregate is as follows: particle size 13.2-16mm accounts for 2wt%, particle size 9.5-13.2mm accounts for 20wt%, particle size 4.75-9.5mm accounts for 25wt%, particle size 2.36-4.75mm accounts for 25wt%, particle size 1.18-2.36mm accounts for 10wt%, particle size 0.6-1.18mm accounts for 8wt%, particle size 0.3-0.6mm accounts for 8wt%, particle size 0.15-0.3mm accounts for 1wt%, and particle size 0.075-0.15mm accounts for 1wt%; the particle size of the mineral powder is less than 0.075mm. The aggregate and the mineral powder are both limestone, the cement is silicate cement, and the bentonite is sodium-based bentonite.

[0051] The mass percentage of each substance in the asphalt cold patching liquid is 75wt% of the base asphalt, 2.2wt% of the modifier, 0.8wt% of the anti-stripping agent, and 22wt% of the diluent. The amount of the diluent increases with the amount of the modifier. In this embodiment, the modifier and the diluent are both added in the minimum amount.

[0052] The base asphalt is No. 70 base asphalt; the modifier is SBS modifier; the anti-stripping agent is a non-amine anti-stripping agent, which is a nitrogen-containing complex, and the nitrogen-containing complex is an AR-I type anti-stripping agent produced by Shenzhen Jinlong Chemical Technology Co., Ltd., which is a solid powder; the diluent is D60 dearomatized solvent oil, which is made from straight-run distillate oil, hydrocracking distillate oil or low-sulfur straight-run jet fuel, and is fractionated after deep desulfurization, dearomatization and hydrogenation refining, with a distillation range of 180-230°C, a closed cup flash point of 60-70°C, an aromatic content of less than 0.03wt%, a sulfur content of less than 0.2mg / kg, and a saturated hydrocarbon content of more than 99.9%. The D60 dearomatized solvent oil is produced by Jinan Yuanyang Chemical Co., Ltd.

[0053] like Figure 1 As shown, this embodiment also provides a method for preparing a cold patch asphalt mixture based on dearomatized solvent oil, which is used to prepare the cold patch asphalt mixture based on dearomatized solvent oil, and includes the following steps in order:

[0054] Step 1: Prepare asphalt cold make-up liquid according to the design requirements, and put the prepared asphalt cold make-up liquid into an oven for heat preservation and standby use;

[0055] Step 2: Weigh aggregate, mineral powder, cement, bentonite, and asphalt cold make-up liquid according to design requirements for use;

[0056] Step 3: putting the aggregate, mineral powder, cement and bentonite into an oven for drying. After the drying is completed, lowering the temperature in the oven to a certain temperature so that the aggregate, mineral powder, cement and bentonite are kept warm at the lowered temperature for later use;

[0057] Step 4: Heat the mixing pot to a certain temperature, then put the aggregate, cement and bentonite kept warm in the oven into the mixing pot and stir them with a stirrer;

[0058] Step 5: Keep the temperature of the mixing pot unchanged, add the asphalt cold make-up liquid kept warm in the oven into the mixing pot, and stir with a stirrer;

[0059] Step 6: Keep the temperature of the mixing pot unchanged, add the mineral powder kept warm in the oven into the mixing pot, and stir it with a stirrer to obtain a cold patch asphalt mixture based on dearomatized solvent oil.

[0060] In step 1, the method for preparing the asphalt cold make-up fluid comprises the following steps in order:

[0061] Step (1): weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements and set aside;

[0062] Step (2): placing the matrix asphalt in a container, and then placing the container containing the matrix asphalt in an oven for heating at a temperature of 110° C. for a heating time of 1.5 h;

[0063] Step (3): After the heating is completed, the container containing the base asphalt is taken out from the oven, the modifier is added into the container, and then the container containing the base asphalt and the modifier is placed on an induction cooker for heating, while stirring and heating until the base asphalt and the modifier are completely mixed, the heating temperature is raised to 165°C, and the heating time is 18 minutes;

[0064] Step (4): placing the container containing the base asphalt and the modifier into an oil bath, and using a high-speed shearing instrument to perform shearing and stirring to obtain modified asphalt, the temperature of the oil bath is 165° C., the shearing speed is 5500 r / min, and the shearing and stirring time is 0.8 h;

[0065] Step (5): lower the temperature of the oil bath to a certain temperature, then use a stirrer to add the diluent while stirring until the modified asphalt and the diluent are completely mixed, lower the temperature of the oil bath to 110°C, and stir for 18 minutes;

[0066] Step (6): Continue stirring with a stirrer while cooling down. After the temperature of the oil bath drops to a certain temperature, add the anti-stripping agent and stir until the anti-stripping agent is completely blended to obtain the asphalt cold fill liquid. The temperature of the oil bath drops to 70°C and the stirring time is 18 minutes.

[0067] In step one, the insulation temperature of the asphalt cold make-up liquid is 70°C; in step three, the drying temperature is 125°C, the drying time is 3.5h, and the temperature in the oven is reduced to 80°C, that is, the insulation temperature of the aggregate, mineral powder, cement, and bentonite is 80°C; in step four, the temperature of the mixing pot is heated to 70°C, and the stirring time is 105s; in step five, the temperature of the mixing pot is 70°C, and the stirring time is 105s; in step six, the temperature of the mixing pot is 70°C, and the stirring time is 105s.

[0068] In this embodiment, the content of organic volatiles in the D60 dearomatized solvent oil used is tested, and the test results are shown in Table 1. Since no environmental protection standards for road cold patch asphalt mixtures have been formulated at present, GC-MS (gas chromatography-mass spectrometry) is used after comprehensive consideration, and 73 representative organic volatiles that are irritating to the human body, even toxic and flammable and explosive are selected for content testing, including benzene series, organic halides, aldehydes, ketones, alcohols, esters, alkanes, etc. It can be seen from the test data that among the 73 organic volatiles listed, only 12 are contained in the D60 dearomatized solvent oil, and the content of each organic volatile is less than 500μg / ml, which is extremely low.

[0069] Table 1 Test results of volatile organic matter content in D60 dearomatized solvent oil

[0070]

[0071]

[0072] In this embodiment, the AR-I type anti-stripping agent used is as follows Figure 2 As shown, the D60 dearomatized solvent oil used is Figure 3 As shown, the final prepared asphalt cold patching fluid is as follows Figure 4 As shown in Figure 2, the final prepared cold patch asphalt mixture is as follows: Figure 5 shown.

[0073] The oven, induction cooker, mixing pot, oil bath pot, stirrer, high-speed shearing instrument, etc. used in this embodiment are all conventional equipment in the field, and no special requirements are made on the model and structure of the equipment. SBS is styrene-butadiene-styrene block copolymer, and SBR is styrene-butadiene rubber. The aggregate includes nine particle sizes, namely, particle size 13.2-16mm, particle size 9.5-13.2mm, particle size 4.75-9.5mm, particle size 2.36-4.75mm, particle size 1.18-2.36mm, particle size 0.6-1.18mm, particle size 0.3-0.6mm, particle size 0.15-0.3mm, particle size 0.075-0.15mm, that is, 13.2mm≤particle size<16mm, 9.5mm≤particle size The particle size of the mineral powder is less than 0.075mm, that is, 0mm≤particle size<0.075mm. For each particle size, the material is passed through the upper and lower sieve holes in sequence to obtain a particle size between the upper and lower sieve holes, for example: the particle size is 1.18-2.36mm (1.18mm≤particle size<2.36mm), that is, the material is passed through the 2.36mm sieve hole and the 1.18mm sieve hole in sequence to obtain a particle size between 1.18-2.36mm.

[0074] In the entire preparation process of the asphalt cold patch fluid in this embodiment, the selection of each substance in the asphalt cold patch fluid, the mass percentage of each substance, the order of addition of each substance, the process parameters of each step, etc. are very critical. At the same time, in the entire preparation process of the cold patch asphalt mixture, the selection of each substance in the cold patch asphalt mixture, the mass percentage of each substance, the order of addition of each substance, the process parameters of each step, etc. are also very critical. Only by synergizing the various formula parameters and process parameters can the expected technical effect of this embodiment be achieved.

[0075] In this embodiment, D60 dearomatized solvent oil is used as a diluent to replace diesel, light gasoline, aromatic solvent oil, etc., which is colorless, non-toxic, has very low odor, narrow fraction, strong solubility, good volatility, saturated hydrocarbon content greater than 99.9%, and has good oxidation stability while ensuring good solubility. At room temperature and natural ventilation conditions, D60 dearomatized solvent oil can be used normally without taking special safety and fire prevention measures, and its contact risk is very low, the production and construction process is safer, and the impact on the atmospheric environment and workers' health is minimal. The evaporation rate of D60 dearomatized solvent oil is moderate, and the degree of evaporation is more complete, which can ensure that the construction site has enough time for sufficient paving and compaction, and form a better combination with the original road surface. In addition, D60 dearomatized solvent oil has a very small effect on the performance of cold-patch asphalt mixture, and there is no need to use expensive materials such as resins. Only a small amount of anti-stripping agent is added to perfectly meet the performance requirements of hot-mix asphalt mixture, and the production cost is low.

[0076] The cold-patch asphalt mixture based on dearomatized solvent oil and its preparation method in this embodiment have the following beneficial effects: (1) The D60 dearomatized solvent oil used is a highly environmentally friendly, non-polluting excellent solvent, which is colorless, non-toxic, and has very little odor, and can provide a good construction environment for workers; at the same time, its saturated hydrocarbon content is greater than 99.9%, its aromatic hydrocarbon content is less than 0.03wt%, and its sulfur content is less than 0.2mg / kg, which has very little impact on the environment. (2) It is the first time to propose the use of D60 dearomatized solvent oil as a diluent, which perfectly replaces the diesel, light gasoline, aromatic solvent oil and other substances used in the traditional preparation of cold-patch asphalt mixture; D60 dearomatized solvent oil has good solubility for asphalt, and the appropriate volatilization rate can not only meet the construction time requirements but also improve the early strength as soon as possible. (3) The prepared cold-patch asphalt mixture has excellent comprehensive performance, perfectly meets the performance requirements of hot-mix asphalt mixture, and has a longer service life. (4) The prepared cold-patch asphalt mixture can quickly form strength, and traffic can be opened faster after the potholes are repaired, with little impact on road traffic.

[0077] Embodiment 2:

[0078] According to another preferred embodiment of the cold patch asphalt mixture based on dearomatized solvent oil and its preparation method of the present invention, its material ratio, preparation process, equipment used, technical principle, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0079] The mass percentage of each substance in the cold patch asphalt mixture is 91wt% of aggregate, 2wt% of mineral powder, 2wt% of cement, 0.4wt% of bentonite, and 4.6wt% of asphalt cold patch liquid. The ratio of the sum of the masses of the cement and the bentonite to the mass of the asphalt cold patch liquid is 0.05:1, ensuring that it is within the range of 0.05-0.06:1; D60 dearomatized solvent oil is used as a diluent in the asphalt cold patch liquid.

[0080] The aggregate includes nine particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 5wt%, particle size 9.5-13.2mm accounts for 15wt%, particle size 4.75-9.5mm accounts for 35wt%, particle size 2.36-4.75mm accounts for 15wt%, particle size 1.18-2.36mm accounts for 15wt%, particle size 0.6-1.18mm accounts for 5wt%, particle size 0.3-0.6mm accounts for 8wt%, particle size 0.15-0.3mm accounts for 1wt%, and particle size 0.075-0.15mm accounts for 1wt%; the particle size of the mineral powder is less than 0.075mm. The aggregate and the mineral powder are both limestone, the cement is silicate cement, and the bentonite is sodium-based bentonite.

[0081] The mass percentage of each substance in the asphalt cold patching liquid is 74wt% for base asphalt, 2.4wt% for modifier, 0.6wt% for anti-stripping agent and 23wt% for diluent. The amount of diluent added increases with the amount of modifier added. Within the mass percentage range of the modifier and the diluent, when the amount of modifier added increases by 0.2wt%, the amount of diluent added increases by 1wt% accordingly, ensuring that it is within the range of 1-1.5wt%.

[0082] The base asphalt is No. 70 base asphalt; the modifier is SBS modifier; the anti-stripping agent is a non-amine anti-stripping agent, which is a nitrogen-containing complex, and the nitrogen-containing complex is an AR-I type anti-stripping agent produced by Shenzhen Jinlong Chemical Technology Co., Ltd., which is a solid powder; the diluent is D60 dearomatized solvent oil, which is made from straight-run distillate oil, hydrocracking distillate oil or low-sulfur straight-run jet fuel, and is fractionated after deep desulfurization, dearomatization and hydrogenation refining, with a distillation range of 180-230°C, a closed cup flash point of 60-70°C, an aromatic content of less than 0.03wt%, a sulfur content of less than 0.2mg / kg, and a saturated hydrocarbon content of more than 99.9%. The D60 dearomatized solvent oil is produced by Jinan Yuanyang Chemical Co., Ltd.

[0083] In step 1, the method for preparing the asphalt cold make-up fluid comprises the following steps in order:

[0084] Step (1): weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements and set aside;

[0085] Step (2): placing the matrix asphalt in a container, and then placing the container containing the matrix asphalt in an oven for heating at a temperature of 100° C. for a heating time of 2 h;

[0086] Step (3): After the heating is completed, take out the container containing the base asphalt from the oven, add the modifier into the container, and then place the container containing the base asphalt and the modifier on an induction cooker for heating, stirring while heating until the base asphalt and the modifier are completely mixed, the heating temperature is raised to 160° C., and the heating time is 20 min;

[0087] Step (4): placing the container containing the base asphalt and the modifier into an oil bath, and using a high-speed shearing instrument to perform shearing and stirring to obtain modified asphalt, the temperature of the oil bath is 160° C., the shearing speed is 5000 r / min, and the shearing and stirring time is 1 h;

[0088] Step (5): lower the temperature of the oil bath to a certain temperature, then use a stirrer to add the diluent while stirring until the modified asphalt and the diluent are completely mixed, lower the temperature of the oil bath to 100°C, and stir for 20 minutes;

[0089] Step (6): Continue stirring with a stirrer while cooling down. After the temperature of the oil bath drops to a certain temperature, add the anti-stripping agent and stir until the anti-stripping agent is completely blended to obtain the asphalt cold fill liquid. The temperature of the oil bath drops to 60°C and the stirring time is 20 minutes.

[0090] In step one, the insulation temperature of the asphalt cold make-up liquid is 60°C; in step three, the drying temperature is 120°C, the drying time is 4h, and the temperature in the oven is reduced to 70°C, that is, the insulation temperature of the aggregate, mineral powder, cement, and bentonite is 70°C; in step four, the temperature of the mixing pot is heated to 60°C, and the stirring time is 120s; in step five, the temperature of the mixing pot is 60°C, and the stirring time is 120s; in step six, the temperature of the mixing pot is 60°C, and the stirring time is 120s.

[0091] Embodiment three:

[0092] According to another preferred embodiment of the cold patch asphalt mixture based on dearomatized solvent oil and its preparation method of the present invention, its material ratio, preparation process, equipment used, technical principle, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0093] The mass percentage of each substance in the cold patch asphalt mixture is 89wt% of aggregate, 2wt% of mineral powder, 3wt% of cement, 0.5wt% of bentonite, and 5.5wt% of asphalt cold patch liquid. The ratio of the sum of the masses of the cement and the bentonite to the mass of the asphalt cold patch liquid is 0.06:1, ensuring that it is within the range of 0.05-0.06:1; D60 dearomatized solvent oil is used as a diluent in the asphalt cold patch liquid.

[0094] The aggregate includes nine particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 3wt%, particle size 9.5-13.2mm accounts for 18wt%, particle size 4.75-9.5mm accounts for 30wt%, particle size 2.36-4.75mm accounts for 20wt%, particle size 1.18-2.36mm accounts for 12wt%, particle size 0.6-1.18mm accounts for 6wt%, particle size 0.3-0.6mm accounts for 5wt%, particle size 0.15-0.3mm accounts for 3wt%, and particle size 0.075-0.15mm accounts for 3wt%; the particle size of the mineral powder is less than 0.075mm. The aggregate and the mineral powder are both limestone, the cement is silicate cement, and the bentonite is sodium-based bentonite.

[0095] The mass percentage of each substance in the asphalt cold patching liquid is 73wt% for base asphalt, 2.6wt% for modifier, 0.2wt% for anti-stripping agent and 24.2wt% for diluent. The amount of diluent added increases with the amount of modifier added. Within the mass percentage range of the modifier and the diluent, when the amount of modifier added increases by 0.2wt%, the amount of diluent added increases by 1.2wt% accordingly, ensuring that it is within the range of 1-1.5wt%.

[0096] The base asphalt is No. 70 base asphalt; the modifier is SBS modifier; the anti-stripping agent is a non-amine anti-stripping agent, which is a nitrogen-containing complex, and the nitrogen-containing complex is an AR-I type anti-stripping agent produced by Shenzhen Jinlong Chemical Technology Co., Ltd., which is a solid powder; the diluent is D60 dearomatized solvent oil, which is made from straight-run distillate oil, hydrocracking distillate oil or low-sulfur straight-run jet fuel, and is fractionated after deep desulfurization, dearomatization and hydrogenation refining, with a distillation range of 180-230°C, a closed cup flash point of 60-70°C, an aromatic content of less than 0.03wt%, a sulfur content of less than 0.2mg / kg, and a saturated hydrocarbon content of more than 99.9%. The D60 dearomatized solvent oil is produced by Jinan Yuanyang Chemical Co., Ltd.

[0097] In step 1, the method for preparing the asphalt cold make-up fluid comprises the following steps in order:

[0098] Step (1): weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements and set aside;

[0099] Step (2): placing the matrix asphalt in a container, and then placing the container containing the matrix asphalt in an oven for heating at a temperature of 120° C. for a heating time of 1 h;

[0100] Step (3): After the heating is completed, take out the container containing the base asphalt from the oven, add the modifier into the container, and then place the container containing the base asphalt and the modifier on an induction cooker for heating, stirring while heating until the base asphalt and the modifier are completely mixed, the heating temperature is raised to 170°C, and the heating time is 15 minutes;

[0101] Step (4): placing the container containing the base asphalt and the modifier into an oil bath, and using a high-speed shearing instrument to perform shearing and stirring to obtain modified asphalt, the temperature of the oil bath is 170° C., the shearing speed is 6000 r / min, and the shearing and stirring time is 0.5 h;

[0102] Step (5): lower the temperature of the oil bath to a certain temperature, then use a stirrer to add the diluent while stirring until the modified asphalt and the diluent are completely mixed, lower the temperature of the oil bath to 120°C, and stir for 15 minutes;

[0103] Step (6): Continue stirring with a stirrer while cooling down. After the temperature of the oil bath drops to a certain temperature, add the anti-stripping agent and stir until the anti-stripping agent is completely blended to obtain the asphalt cold fill liquid. The temperature of the oil bath drops to 80°C and the stirring time is 15 minutes.

[0104] In step one, the insulation temperature of the asphalt cold make-up liquid is 80°C; in step three, the drying temperature is 130°C, the drying time is 3h, and the temperature in the oven is reduced to 90°C, that is, the insulation temperature of the aggregate, mineral powder, cement, and bentonite is 90°C; in step four, the temperature of the mixing pot is heated to 80°C, and the stirring time is 90s; in step five, the temperature of the mixing pot is 80°C, and the stirring time is 90s; in step six, the temperature of the mixing pot is 80°C, and the stirring time is 90s.

[0105] Embodiment 4:

[0106] According to another preferred embodiment of the cold patch asphalt mixture based on dearomatized solvent oil and its preparation method of the present invention, its material ratio, preparation process, equipment used, technical principle, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0107] The mass percentage of each substance in the cold patch asphalt mixture is 90wt% of aggregate, 2wt% of mineral powder, 2.6wt% of cement, 0.6wt% of bentonite, and 4.8wt% of asphalt cold patch liquid. The ratio of the sum of the masses of the cement and the bentonite to the mass of the asphalt cold patch liquid is 0.052:1, ensuring that it is within the range of 0.05-0.06:1; D60 dearomatized solvent oil is used as a diluent in the asphalt cold patch liquid.

[0108] The aggregate includes nine particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 4wt%, particle size 9.5-13.2mm accounts for 19wt%, particle size 4.75-9.5mm accounts for 32wt%, particle size 2.36-4.75mm accounts for 17wt%, particle size 1.18-2.36mm accounts for 11wt%, particle size 0.6-1.18mm accounts for 7wt%, particle size 0.3-0.6mm accounts for 6wt%, particle size 0.15-0.3mm accounts for 2wt%, and particle size 0.075-0.15mm accounts for 2wt%; the particle size of the mineral powder is less than 0.075mm. The aggregate and the mineral powder are both limestone, the cement is silicate cement, and the bentonite is sodium-based bentonite.

[0109] The mass percentage of each substance in the asphalt cold patching liquid is 71wt% for base asphalt, 2.8wt% for modifier, 0.7wt% for anti-stripping agent and 25.5wt% for diluent. The amount of diluent added increases with the amount of modifier added. Within the mass percentage range of the modifier and the diluent, when the amount of modifier added increases by 0.2wt%, the amount of diluent added increases by 1.3wt% accordingly, ensuring that it is within the range of 1-1.5wt%.

[0110] The base asphalt is No. 90 base asphalt; the modifier is SBR modifier; the anti-stripping agent is a non-amine anti-stripping agent, which is a nitrogen-containing complex, and the nitrogen-containing complex is an AR-I type anti-stripping agent produced by Shenzhen Jinlong Chemical Technology Co., Ltd., which is a solid powder; the diluent is D60 dearomatized solvent oil, which is made from straight-run distillate oil, hydrocracking distillate oil or low-sulfur straight-run jet fuel, and is fractionated after deep desulfurization, dearomatization and hydrogenation refining, with a distillation range of 180-230°C, a closed cup flash point of 60-70°C, an aromatic content of less than 0.03wt%, a sulfur content of less than 0.2mg / kg, and a saturated hydrocarbon content of more than 99.9%. The D60 dearomatized solvent oil is produced by Jinan Yuanyang Chemical Co., Ltd.

[0111] In step 1, the method for preparing the asphalt cold make-up fluid comprises the following steps in order:

[0112] Step A: weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements for use;

[0113] Step B: Put the base asphalt into a container, and then put the container containing the base asphalt into an oven for heating at a temperature of 110° C. for a heating time of 1.5 h;

[0114] Step C: After the heating is completed, take out the container containing the matrix asphalt from the oven, add the diluent into the container, and then put the container containing the matrix asphalt and the diluent into an oil bath, and stir with a stirrer until the matrix asphalt and the diluent are completely melted. The temperature of the oil bath is 70°C, and the stirring time is 12 minutes;

[0115] Step D: Keep the temperature of the oil bath constant, continue stirring with a stirrer, and add the anti-stripping agent while stirring until the anti-stripping agent is completely integrated, so as to obtain the diluted matrix asphalt. The temperature of the oil bath is 70°C, and the stirring time is 12 minutes;

[0116] Step E: Keep the temperature of the oil bath unchanged, continue stirring with a stirrer, and add the modifier while stirring until the diluted base asphalt and the modifier are completely mixed, and then use a high-speed shear instrument to shear and stir to obtain the asphalt cold makeup liquid. The temperature of the oil bath is 70°C, the stirring time is 22 minutes, the shear speed is 5500r / min, and the shear stirring time is 25 minutes.

[0117] In step one, the insulation temperature of the asphalt cold make-up liquid is 70°C; in step three, the drying temperature is 125°C, the drying time is 3.5h, and the temperature in the oven is reduced to 80°C, that is, the insulation temperature of the aggregate, mineral powder, cement, and bentonite is 80°C; in step four, the temperature of the mixing pot is heated to 70°C, and the stirring time is 105s; in step five, the temperature of the mixing pot is 70°C, and the stirring time is 105s; in step six, the temperature of the mixing pot is 70°C, and the stirring time is 105s.

[0118] Embodiment five:

[0119] According to another preferred embodiment of the cold patch asphalt mixture based on dearomatized solvent oil and its preparation method of the present invention, its material ratio, preparation process, equipment used, technical principle, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0120] The mass percentage of each substance in the cold patch asphalt mixture is 89wt% of aggregate, 3wt% of mineral powder, 2.3wt% of cement, 0.4wt% of bentonite, and 5.3wt% of asphalt cold patch liquid. The ratio of the sum of the masses of the cement and the bentonite to the mass of the asphalt cold patch liquid is 0.058:1, ensuring that it is within the range of 0.05-0.06:1; D60 dearomatized solvent oil is used as a diluent in the asphalt cold patch liquid.

[0121] The aggregate includes nine particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 5wt%, particle size 9.5-13.2mm accounts for 16wt%, particle size 4.75-9.5mm accounts for 28wt%, particle size 2.36-4.75mm accounts for 22wt%, particle size 1.18-2.36mm accounts for 13wt%, particle size 0.6-1.18mm accounts for 6wt%, particle size 0.3-0.6mm accounts for 6wt%, particle size 0.15-0.3mm accounts for 2wt%, and particle size 0.075-0.15mm accounts for 2wt%; the particle size of the mineral powder is less than 0.075mm. The aggregate and the mineral powder are both limestone, the cement is silicate cement, and the bentonite is sodium-based bentonite.

[0122] The mass percentage of each substance in the asphalt cold patching liquid is 69.8wt% for base asphalt, 3.0wt% for modifier, 0.3wt% for anti-stripping agent and 26.9wt% for diluent. The amount of diluent added increases with the amount of modifier added. Within the mass percentage range of the modifier and the diluent, when the amount of modifier added increases by 0.2wt%, the amount of diluent added increases by 1.4wt% accordingly, ensuring that it is within the range of 1-1.5wt%.

[0123] The base asphalt is No. 90 base asphalt; the modifier is SBS modifier; the anti-stripping agent is a non-amine anti-stripping agent, and the non-amine anti-stripping agent is polyphosphoric acid; the diluent is D60 dearomatized solvent oil, and the D60 dearomatized solvent oil is made from straight-run distillate oil, hydrocracking distillate oil or low-sulfur straight-run jet fuel as raw materials, and is fractionated after deep desulfurization, dearomatization and hydrogenation refining, with a distillation range of 180-230°C, a closed cup flash point of 60-70°C, an aromatic content of less than 0.03wt%, a sulfur content of less than 0.2mg / kg, and a saturated hydrocarbon content of more than 99.9%. The D60 dearomatized solvent oil is produced by Jinan Yuanyang Chemical Co., Ltd.

[0124] In step 1, the method for preparing the asphalt cold make-up fluid comprises the following steps in order:

[0125] Step A: weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements for use;

[0126] Step B: Put the matrix asphalt into a container, and then put the container containing the matrix asphalt into an oven for heating at a temperature of 100° C. for a heating time of 2 h;

[0127] Step C: After the heating is completed, take out the container containing the matrix asphalt from the oven, add the diluent into the container, and then put the container containing the matrix asphalt and the diluent into an oil bath pot, and stir with a stirrer until the matrix asphalt and the diluent are completely melted. The temperature of the oil bath pot is 60°C, and the stirring time is 15 minutes;

[0128] Step D: Keep the temperature of the oil bath constant, continue stirring with a stirrer, and add the anti-stripping agent while stirring until the anti-stripping agent is completely integrated, so as to obtain the diluted matrix asphalt. The temperature of the oil bath is 60°C, and the stirring time is 15 minutes;

[0129] Step E: Keep the temperature of the oil bath unchanged, continue stirring with an agitator, and add the modifier while stirring until the diluted base asphalt and the modifier are completely mixed, and then use a high-speed shear instrument to shear and stir to obtain the asphalt cold makeup liquid. The temperature of the oil bath is 60°C, the stirring time is 25 minutes, the shear speed is 5000r / min, and the shear stirring time is 30 minutes.

[0130] In step one, the insulation temperature of the asphalt cold make-up liquid is 60°C; in step three, the drying temperature is 120°C, the drying time is 4h, and the temperature in the oven is reduced to 70°C, that is, the insulation temperature of the aggregate, mineral powder, cement, and bentonite is 70°C; in step four, the temperature of the mixing pot is heated to 60°C, and the stirring time is 120s; in step five, the temperature of the mixing pot is 60°C, and the stirring time is 120s; in step six, the temperature of the mixing pot is 60°C, and the stirring time is 120s.

[0131] Embodiment six:

[0132] According to another preferred embodiment of the cold patch asphalt mixture based on dearomatized solvent oil and its preparation method of the present invention, its material ratio, preparation process, equipment used, technical principle, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0133] The mass percentage of each substance in the cold patch asphalt mixture is 90wt% of aggregate, 2wt% of mineral powder, 2wt% of cement, 0.6wt% of bentonite, and 5.4wt% of asphalt cold patch liquid. The ratio of the sum of the masses of the cement and the bentonite to the mass of the asphalt cold patch liquid is 0.059:1, ensuring that it is within the range of 0.05-0.06:1; D60 dearomatized solvent oil is used as a diluent in the asphalt cold patch liquid.

[0134] The aggregate includes nine particle sizes, and the mass percentage of each particle size in the aggregate is: 3wt% for particle size 9.5-13.2mm, 19wt% for particle size 9.5-13.2mm, 30wt% for particle size 4.75-9.5mm, 20wt% for particle size 2.36-4.75mm, 12wt% for particle size 1.18-2.36mm, 6wt% for particle size 0.6-1.18mm, 6wt% for particle size 0.3-0.6mm, 2wt% for particle size 0.15-0.3mm, and 2wt% for particle size 0.075-0.15mm; the particle size of the mineral powder is less than 0.075mm. The aggregate and the mineral powder are both limestone, the cement is silicate cement, and the bentonite is sodium-based bentonite.

[0135] The mass percentage of each substance in the asphalt cold patching liquid is 68wt% for base asphalt, 3.2wt% for modifier, 0.4wt% for anti-stripping agent and 28.4wt% for diluent. The amount of diluent added increases with the amount of modifier added. Within the mass percentage range of the modifier and the diluent, when the amount of modifier added increases by 0.2wt%, the amount of diluent added increases by 1.5wt% accordingly, ensuring that it is within the range of 1-1.5wt%.

[0136] The base asphalt is No. 90 base asphalt; the modifier is SBS modifier; the anti-stripping agent is a non-amine anti-stripping agent, and the non-amine anti-stripping agent is a phosphate ester; the diluent is D60 dearomatized solvent oil, and the D60 dearomatized solvent oil is made from straight-run distillate oil, hydrocracking distillate oil or low-sulfur straight-run jet fuel, and is fractionated after deep desulfurization, dearomatization and hydrogenation refining, with a distillation range of 180-230°C, a closed cup flash point of 60-70°C, an aromatic content of less than 0.03wt%, a sulfur content of less than 0.2mg / kg, and a saturated hydrocarbon content of more than 99.9%. The D60 dearomatized solvent oil is produced by Jinan Yuanyang Chemical Co., Ltd.

[0137] In step 1, the method for preparing the asphalt cold make-up fluid comprises the following steps in order:

[0138] Step A: weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements for use;

[0139] Step B: Put the matrix asphalt into a container, and then put the container containing the matrix asphalt into an oven for heating at a temperature of 120° C. for a heating time of 1 hour;

[0140] Step C: After the heating is completed, take out the container containing the matrix asphalt from the oven, add the diluent into the container, and then put the container containing the matrix asphalt and the diluent into an oil bath, and stir with a stirrer until the matrix asphalt and the diluent are completely melted. The temperature of the oil bath is 80°C, and the stirring time is 10 minutes;

[0141] Step D: Keep the temperature of the oil bath constant, continue stirring with a stirrer, and add the anti-stripping agent while stirring until the anti-stripping agent is completely integrated, so as to obtain the diluted matrix asphalt. The temperature of the oil bath is 80° C., and the stirring time is 10 minutes;

[0142] Step E: Keep the temperature of the oil bath unchanged, continue stirring with an agitator, and add the modifier while stirring until the diluted base asphalt and the modifier are completely mixed, and then use a high-speed shear instrument to shear and stir to obtain the asphalt cold makeup liquid. The temperature of the oil bath is 80°C, the stirring time is 20 minutes, the shear speed is 6000r / min, and the shear stirring time is 20 minutes.

[0143] In step one, the insulation temperature of the asphalt cold make-up liquid is 80°C; in step three, the drying temperature is 130°C, the drying time is 3h, and the temperature in the oven is reduced to 90°C, that is, the insulation temperature of the aggregate, mineral powder, cement, and bentonite is 90°C; in step four, the temperature of the mixing pot is heated to 80°C, and the stirring time is 90s; in step five, the temperature of the mixing pot is 80°C, and the stirring time is 90s; in step six, the temperature of the mixing pot is 80°C, and the stirring time is 90s.

[0144] The cold patch asphalt mixtures prepared in the above six embodiments were respectively subjected to performance tests such as initial stability, molding stability, water stability and dynamic stability, and the test equipment, test environment, test conditions, sample shape and size used were all the same.

[0145] 1. Initial stability and molding stability test

[0146] Weigh 980g of cold patch asphalt mixture (the actual mass is based on the control specimen height of 63.5±1.5mm) and put it into the test mold. Compact it 50 times on both sides and place it upright at room temperature for 2h before demoulding. After curing the specimen in a water tank at 25±1℃ for 30min, measure the Marshall stability of the specimen, which is the initial stability. The test results are shown in Table 1.

[0147] Weigh 1100g of cold patch asphalt mixture (the actual mass is based on the specimen height of 63.5±1.5mm) and put it into the test mold, and compact it on both sides 50 times. Place the specimen and the test mold in an oven at 105±5℃ in a side-up manner for 24 hours, take it out and compact it on both sides 25 times, then place the specimen and the test mold upright at room temperature for 24 hours before demolding. After curing the specimen in a water tank at 60±1℃ for 30 minutes, measure the Marshall stability of the specimen, which is the molding stability. The test results are shown in Table 2.

[0148] Table 2 Test results of initial stability and forming stability of cold patch asphalt mixture

[0149] Example Outdoor 32-35℃ initial strength (KN) Outdoor 23-25℃ initial strength (KN) Forming stability (KN) Embodiment 1 7.34 5.20 10.20 Embodiment 2 9.13 5.99 11.65 Embodiment 3 8.92 5.68 10.60 Embodiment 4 7.25 5.12 10.32 Embodiment 5 7.12 5.15 10.12 Embodiment 6 7.05 5.08 10.09

[0150] 2. Water stability test

[0151] Weigh 1100g of cold patch asphalt mixture (the actual mass is based on the specimen height of 63.5±1.5mm) and put it into the test mold, and compact it on both sides 50 times. Place the specimen and the test mold in an oven at 105±5℃ in a side-up position for 24 hours, take it out and compact it on both sides 25 times, and then place the specimen and the test mold in an upright position at room temperature for 24 hours before demolding.

[0152] The specimens were randomly divided into two groups, with no less than four specimens in each group. One group of specimens was kept in a constant temperature water bath at 60°C for 60 minutes and then subjected to the Marshall test. The other group of specimens was kept in a constant temperature water bath at 60°C for 48 hours and then subjected to the Marshall test. The ratio of the two groups was the residual stability ratio. The test results are shown in Table 3.

[0153] Table 3 Test results of water-residual stability of cold-patch asphalt mixture

[0154]

[0155]

[0156] The specimens were randomly divided into two groups, with no less than four specimens in each group. The first group of specimens was placed on a platform and stored at room temperature for later use. The second group of specimens was placed in a vacuum dryer, the water inlet hose was closed, and the vacuum pump was started to make the vacuum degree of the dryer reach 98.3kPa (730mmHg) or above, and maintained for 15 minutes. Then the water inlet hose was opened, and the cold water flow entered by negative pressure made the specimens completely immersed in water. After immersion in water for 15 minutes, the normal pressure was restored. The second group of specimens was taken out and placed in a plastic bag, and about 10mL of water was added. The bag was tied tightly, and the specimens were placed in a constant temperature refrigerator with a freezing temperature of -18℃±2℃ for 16±1h. After taking out the specimens, they were immediately placed in a constant temperature water tank at 60±0.5℃, soaked for 3 minutes, and then the plastic bag was removed, and the temperature was kept for 24±0.5h. All the specimens of the first and second groups were immersed in a constant temperature water bath at a temperature of 25±0.5℃ and kept warm for 2h±10min. The test results of the first group of specimens were splitting strength, and the test results of the second group of specimens were freeze-thaw cycle splitting strength. The ratio of the test results of the second group to the first group was the freeze-thaw splitting tensile strength ratio. The test results are shown in Table 4.

[0157] Table 4 Splitting strength and freeze-thaw cycle splitting strength test results of cold-patch asphalt mixture

[0158] Example Average splitting strength (MPa) Average splitting strength after freeze-thaw cycles (MPa) Freeze-thaw splitting strength ratio (%) Embodiment 1 0.50 0.40 80％ Embodiment 2 0.51 0.41 81％ Embodiment 3 0.50 0.40 80％ Embodiment 4 0.49 0.39 80％ Embodiment 5 0.48 0.37 78％ Embodiment 6 0.48 0.37 78％

[0159] 3. Dynamic stability test

[0160] Use a test mold with a length of 300mm×width of 300mm×thickness of 50mm. Use a small shovel to slightly mix all the cold patch asphalt mixture, and then evenly put it into the test mold in a circle from the edge to the center in sequence. The middle part should be slightly higher than the surroundings. Before molding, preheat the rolling wheel to about 80℃, then place the test mold containing the cold patch asphalt mixture on the platform of the wheel roller, gently put down the rolling wheel, and adjust the total load to 9KN (linear load 300N / cm); start the wheel roller, roll two round trips (4 times) and then stop; unload the load, lift the rolling wheel, turn the direction of the test piece, and continue to roll with the same load until the surface of the test piece is flush with the top edge of the test mold; after rolling, quickly place the test piece in an electric blast drying oven at 60℃ to dry to constant weight.

[0161] The specimen and the test mold are placed in a constant temperature room that has reached the test temperature of 60±1℃, and kept warm for 5-12h. After the insulation is completed, the specimen and the test mold are moved to the test bench of the wheel rutting test machine, and the test wheel is in the center of the specimen, and its running direction is consistent with the rolling or driving direction of the specimen. The test temperature is 60℃ and the wheel pressure is 0.7MPa; the rutting deformation automatic recorder is turned on, and the test machine is started, and the test wheel is moved back and forth for about 1h, and the rutting test is completed. The test results are shown in Table 5.

[0162] Table 5 Dynamic stability test results of cold patch asphalt mixture

[0163]

[0164]

[0165] It can be seen from the test results of Tables 2-5 that the cold-patch asphalt mixture prepared in the above embodiment has excellent comprehensive performance and can meet the performance requirements of hot-mix asphalt mixture. According to the requirements of "Technical Specifications for Highway Asphalt Pavement Construction" (JTG F40-2004): the Marshall stability of hot-mix asphalt mixture for expressways and first-class highways is not less than 8KN, the residual stability of the water-immersed Marshall test is not less than 80%, the residual strength ratio of the freeze-thaw splitting test is not less than 75%, and the dynamic stability in the hot summer zone is not less than 2800 times / mm. In addition, from the initial strength test results, the initial strength at 32-35℃ (close to the summer temperature) outdoors is not less than 7KN, and the initial strength at 23-25℃ (close to the spring and autumn temperature) outdoors is not less than 5KN, which shows that the cold-patch asphalt mixture can quickly form strength, which helps to open traffic faster after repairing potholes and avoid affecting road traffic.

[0166] The AR-I anti-stripping agent used in the above examples was purchased from Shenzhen Jinlong Chemical Technology Co., Ltd., D60 dearomatized solvent oil was purchased from Jinan Yuanyang Chemical Co., Ltd., aggregate, mineral powder, cement, bentonite, matrix asphalt, SBS modifier, SBR modifier was purchased from Beijing Municipal Road and Bridge Building Materials Group Co., Ltd., and polyphosphoric acid and phosphate ester were purchased from Aladdin Reagent Co., Ltd.

[0167] Special note: The technical solution of the present invention involves many parameters, and the synergistic effects between the various parameters need to be comprehensively considered to obtain the beneficial effects and significant progress of the present invention. Moreover, the value ranges of the various parameters in the technical solution are obtained after a large number of experiments. For each parameter and the combination of each parameter, the inventor has recorded a large amount of experimental data. Due to space limitations, the specific experimental data will not be disclosed here.

[0168] It is not difficult for those skilled in the art to understand that the cold patch asphalt mixture based on dearomatized solvent oil and the preparation method thereof of the present invention include any combination of the invention content and specific implementation methods of the above-mentioned invention specification and the various parts shown in the drawings. Due to the limited space and to make the specification concise, the various schemes composed of these combinations are not described one by one. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A cold patch asphalt mixture based on dearomatized solvent oil, characterized in that: The mass percentage of each substance in the cold patch asphalt mixture is 89-91wt% of aggregate, 2-3wt% of mineral powder, 2-3wt% of cement, 0.4-0.6wt% of bentonite, and 4-6wt% of asphalt cold patch liquid, and the ratio of the mass of the asphalt cold patch liquid to the sum of the mass of the aggregate and the mineral powder is 0.05-0.06:1; The asphalt cold patching fluid uses D60 dearomatized solvent oil as a diluent.

2. The cold patch asphalt mixture based on dearomatized solvent oil according to claim 1, characterized in that: The aggregate includes nine particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 2-5wt%, particle size 9.5-13.2mm accounts for 15-20wt%, particle size 4.75-9.5mm accounts for 25-35wt%, particle size 2.36-4.75mm accounts for 15-25wt%, particle size 1.18-2.36mm accounts for 10-15wt%, particle size 0.6-1.18mm accounts for 5-8wt%, particle size 0.3-0.6mm accounts for 5-8wt%, particle size 0.15-0.3mm accounts for 1-3wt%, and particle size 0.075-0.15mm accounts for 1-3wt%. The aggregate is limestone and / or granite; the particle size of the mineral powder is less than 0.075mm, and the mineral powder is limestone.

3. The cold patch asphalt mixture based on dearomatized solvent oil according to claim 2, characterized in that: The cement is any one or more of silicate cement, aluminate cement, sulphoaluminate cement and ferroaluminate cement; the bentonite is any one or more of sodium-based bentonite, calcium-based bentonite and magnesium-based bentonite.

4. The cold patch asphalt mixture based on dearomatized solvent oil according to claim 3, characterized in that: The mass percentages of the substances in the asphalt cold patching liquid are as follows: base asphalt accounts for 68-75wt%, modifier accounts for 2.2-3.4wt%, anti-stripping agent accounts for 0.2-0.8wt%, and diluent accounts for 22-29wt%.

5. The cold patch asphalt mixture based on dearomatized solvent oil according to claim 4, characterized in that: The amount of the diluent added increases with the amount of the modifier added. Within the mass percentage range of the modifier and the diluent, when the amount of the modifier added increases by 0.2wt%, the amount of the diluent added increases by 1-1.5wt% accordingly.

6. The cold patch asphalt mixture based on dearomatized solvent oil according to claim 5, characterized in that: The base asphalt is No. 70 base asphalt or No. 90 base asphalt; the modifier is SBS modifier or SBR modifier; the anti-stripping agent is a non-amine anti-stripping agent, and the non-amine anti-stripping agent is any one or more of polyphosphoric acid, phosphate ester, and nitrogen-containing complex; the diluent is D60 dearomatized solvent oil, and the D60 dearomatized solvent oil is made from straight-run distillate oil, hydrocracking distillate oil or low-sulfur straight-run jet fuel, and is fractionated after deep desulfurization, dearomatization, and hydrogenation refining, with a distillation range of 180-230°C, a closed cup flash point of 60-70°C, an aromatic content of less than 0.03wt%, a sulfur content of less than 0.2mg / kg, and a saturated hydrocarbon content of more than 99.9%.

7. A method for preparing a cold patch asphalt mixture based on dearomatized solvent oil, characterized in that: The cold patch asphalt mixture based on dearomatized solvent oil according to any one of claims 1 to 6 comprises the following steps in chronological order: Step 1: Prepare asphalt cold make-up liquid according to the design requirements, and put the prepared asphalt cold make-up liquid into an oven for heat preservation and standby use; Step 2: Weigh aggregate, mineral powder, cement, bentonite, and asphalt cold make-up liquid according to design requirements for use; Step 3: putting the aggregate, mineral powder, cement and bentonite into an oven for drying. After the drying is completed, lowering the temperature in the oven to a certain temperature so that the aggregate, mineral powder, cement and bentonite are kept warm at the lowered temperature for later use; Step 4: Heat the mixing pot to a certain temperature, then put the aggregate, cement and bentonite kept warm in the oven into the mixing pot and stir them with a stirrer; Step 5: Keep the temperature of the mixing pot unchanged, add the asphalt cold make-up liquid kept warm in the oven into the mixing pot, and stir with a stirrer; Step 6: Keep the temperature of the mixing pot unchanged, add the mineral powder kept warm in the oven into the mixing pot, and stir it with a stirrer to obtain a cold patch asphalt mixture based on dearomatized solvent oil.

8. The method for preparing cold patch asphalt mixture based on dearomatized solvent oil according to claim 7, characterized in that: In step 1, the method for preparing the asphalt cold replenishment fluid comprises the following steps in order: Step (1): weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements and set aside; Step (2): placing the matrix asphalt in a container, and then placing the container containing the matrix asphalt in an oven for heating at a temperature of 100-120° C. for a heating time of 1-2 h; Step (3): After the heating is completed, take out the container containing the base asphalt from the oven, add the modifier into the container, and then place the container containing the base asphalt and the modifier on an induction cooker for heating, stirring while heating until the base asphalt and the modifier are completely blended, the heating temperature is raised to 160-170°C, and the heating time is 15-20 minutes; Step (4): placing the container containing the base asphalt and the modifier into an oil bath, and using a high-speed shearing instrument to perform shearing and stirring to obtain modified asphalt, the temperature of the oil bath is 160-170° C., the shearing speed is 5000-6000 r / min, and the shearing and stirring time is 0.5-1 h; Step (5): lower the temperature of the oil bath to a certain temperature, then use a stirrer to add the diluent while stirring until the modified asphalt and the diluent are completely mixed, lower the temperature of the oil bath to 100-120°C, and stir for 15-20 minutes; Step (6): Continue stirring with a stirrer while cooling down. After the temperature of the oil bath drops to a certain temperature, add the anti-stripping agent and stir until the anti-stripping agent is completely blended to obtain the asphalt cold fill liquid. The temperature of the oil bath drops to 60-80°C and the stirring time is 15-20 minutes.

9. The method for preparing cold patch asphalt mixture based on dearomatized solvent oil according to claim 8, characterized in that: In step 1, another method for preparing the asphalt cold replenishment fluid comprises the following steps in order: Step A: weigh the base asphalt, modifier, anti-stripping agent and diluent according to the design requirements for use; Step B: Put the matrix asphalt into a container, and then put the container containing the matrix asphalt into an oven for heating at a temperature of 100-120° C. for a heating time of 1-2 hours; Step C: After the heating is completed, take out the container containing the matrix asphalt from the oven, add the diluent into the container, and then put the container containing the matrix asphalt and the diluent into an oil bath, and stir with a stirrer until the matrix asphalt and the diluent are completely melted. The temperature of the oil bath is 60-80°C, and the stirring time is 10-15 minutes; Step D: Keep the temperature of the oil bath unchanged, continue stirring with an agitator, add the anti-stripping agent while stirring, until the anti-stripping agent is completely integrated, so as to obtain the diluted base asphalt, the temperature of the oil bath is 60-80°C, and the stirring time is 10-15min; Step E: Keep the temperature of the oil bath unchanged, continue stirring with an agitator, add the modifier while stirring, until the diluted base asphalt and the modifier are completely integrated, and then use a high-speed shear instrument for shear stirring to obtain the asphalt cold replenishment liquid, the temperature of the oil bath is 60-80°C, the stirring time is 20-25min, the shear speed is 5000-6000r / min, and the shear stirring time is 20-30min.

10. The method for preparing cold patch asphalt mixture based on dearomatized solvent oil according to claim 9, characterized in that: In step one, the insulation temperature of the asphalt cold make-up liquid is 60-80°C; in step three, the drying temperature is 120-130°C, the drying time is 3-4h, and the temperature in the oven is reduced to 70-90°C, that is, the insulation temperature of the aggregate, mineral powder, cement, and bentonite is 70-90°C; in step four, the temperature of the mixing pot is heated to 60-80°C, and the stirring time is 90-120s; in step five, the temperature of the mixing pot is 60-80°C, and the stirring time is 90-120s; in step six, the temperature of the mixing pot is 60-80°C, and the stirring time is 90-120s.

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