CN114804760B - Emulsified asphalt plant-mixed cold recycled asphalt mixture and preparation method thereof - Google Patents
Emulsified asphalt plant-mixed cold recycled asphalt mixture and preparation method thereof Download PDFInfo
- Publication number
- CN114804760B CN114804760B CN202210351981.9A CN202210351981A CN114804760B CN 114804760 B CN114804760 B CN 114804760B CN 202210351981 A CN202210351981 A CN 202210351981A CN 114804760 B CN114804760 B CN 114804760B
- Authority
- CN
- China
- Prior art keywords
- asphalt
- rap material
- rap
- parts
- equal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/04—Portland cements
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/16—Waste materials; Refuse from building or ceramic industry
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Abstract
The invention belongs to the field of waste material recovery and regeneration of highways and urban roads, and discloses an emulsified asphalt plant-mixed cold-recycled asphalt mixture, which comprises RAP (asphalt mixture) materials, wherein the surface recycled asphalt of the RAP materials meets the following requirements: the penetration degree at 25 ℃ is more than or equal to 17dmm, the softening point is less than or equal to 70 ℃, the Brookfield rotational viscosity at 135 ℃ is less than or equal to 3500mPa & s, and the rutting factor characterized by G & ltx/sin & delta & gt at 55 ℃ is less than or equal to 150kPa. Compared with the prior art, the method has the advantages that the low-temperature anti-cracking performance of the cold-recycling mixture can be effectively improved by selecting and limiting the surface recycled asphalt in the RAP material, the void ratio is reduced, and important guidance is provided for reasonable utilization of the RAP material in the emulsified asphalt cold-recycling mixture.
Description
Technical Field
The invention relates to the field of waste and old material recycling of highways and urban roads, in particular to an emulsified asphalt plant-mixed cold-recycling asphalt mixture and a preparation method thereof.
Background
The cold recycling asphalt mixture has been a hot point in the research of road material field at home and abroad due to the advantages of construction at normal temperature, high utilization rate of Reclaimed Asphalt (RAP) material, and the like.
In the existing cold recycling engineering practice of emulsified asphalt, the mixing amount of RAP materials can reach 80 percent or even higher. Thus, the properties of the RAP material have a significant impact on the performance of the emulsified asphalt cold-recycled mix, not just its use as "black stone".
The effect of old asphalt on the surface of an RAP material in the emulsified asphalt cold-recycling mixture cannot be ignored, and the low-temperature anti-cracking performance of the cold-recycling mixture can be improved by the presence of the old asphalt. The improvement effect is closely related to the aging degree of the old asphalt, the influence of the old asphalt on the low-temperature cracking resistance of the corresponding cold-recycling mixture is relatively small as the aging degree of the old asphalt increases within a certain aging degree, and the improvement effect of the old asphalt on the low-temperature cracking resistance is seriously weakened when the old asphalt ages beyond a certain aging degree, namely the influence of the aging degree of the old asphalt on the low-temperature cracking resistance of the cold-recycling mixture has a marginal surge effect. As the old asphalt ages, on the one hand, the old asphalt has increased polarity, resulting in better adhesion to aggregate, which contributes to improved low temperature cracking resistance; on the other hand, the cohesion of the old asphalt is reduced, which is disadvantageous for improving the low-temperature cracking resistance. The two opposite effects are in phase with one another for a certain degree of ageing, but when the degree of ageing exceeds a certain limit, the adverse effect of the latter is more pronounced and the reinforcing effect on the polarity of the old bitumen has become less pronounced.
Therefore, the influence of the aging degree of the old asphalt on the surface of the RAP material is considered when the emulsified asphalt cold-recycling mixture is prepared, the improvement effect of the old asphalt on the low-temperature cracking resistance of the old asphalt can be effectively ensured, and an important guide is provided for the reasonable utilization of the RAP material in the emulsified asphalt cold-recycling mixture.
Disclosure of Invention
The invention aims to provide an emulsified asphalt plant-mixed cold-recycled asphalt mixture and a preparation method thereof, which can ensure that old asphalt is within a certain aging degree by limiting the physical rheological index of the recovered old asphalt on the surface of an RAP material, thereby effectively ensuring the improvement effect of the old asphalt on the low-temperature cracking resistance of the cold-recycled mixture and providing important guidance for the reasonable utilization of the RAP material in the emulsified asphalt cold-recycled mixture.
The technical scheme adopted by the invention for solving the technical problems is as follows: an emulsified asphalt plant-mixed cold recycled asphalt mixture comprises an RAP material, new aggregates, a filler, emulsified asphalt, water and cement; the raw materials are as follows in parts by mass: 64 to 77 portions of RAP material, 9 to 23 portions of new aggregate, 3 to 5.5 portions of filler, 3 to 5 portions of emulsified asphalt, 3 to 5 portions of water and 0.5 to 2 portions of cement.
Further, the RAP material is an expressway milling material and comprises a first RAP material, a second RAP material, a third RAP material and a fourth RAP material, wherein the particle size range of the first RAP material is 0.075-4.75 mm, the particle size range of the second RAP material is 4.75-9.5 mm, the particle size range of the third RAP material is 9.5-16 mm, and the particle size range of the fourth RAP material is 16-26.5 mm; the RAP material comprises the following components in parts by mass: 20-35 parts of first RAP material, 14-27 parts of second RAP material, 9-23 parts of third RAP material and 5-18 parts of fourth RAP material.
Further, the content of the old asphalt recycled from the surface of the RAP material accounts for 3.9-5.5% of the mass percent of the RAP material; the surface recycled old asphalt has the following properties: the penetration degree at 25 ℃ is more than or equal to 17dmm, the softening point is less than or equal to 70 ℃, the Brookfield rotational viscosity at 135 ℃ is less than or equal to 3500mPa & s, and the rutting factor characterized by G & ltx/sin & delta & gt at 55 ℃ is less than or equal to 150kPa.
Further, the new aggregate is limestone with the particle size range of 9.5-19 mm; the filler is limestone mineral powder; the emulsified asphalt is cation slow-cracking emulsified asphalt; the cement is ordinary portland cement.
The invention has the advantages that: the method considers that the aging degree of the old asphalt on the surface of the RAP material has marginal surge effect on the low-temperature cracking resistance of the emulsified asphalt plant-mixed cold-recycled asphalt mixture, and ensures that the old asphalt is within a certain aging degree by limiting the physical rheological index of the old asphalt recovered on the surface of the RAP material: on one hand, the old asphalt still has a good cementation effect, and the content of effective asphalt in the cold recycled mixture is improved, so that the improvement effect of the old asphalt on the low-temperature cracking resistance of the cold recycled mixture can be effectively ensured; on the other hand, the characteristic that the RAP material is closer to black stone due to too serious aging of old asphalt is avoided, so that some coarse RAP materials formed by cementing fine materials are easy to disperse in the construction and subsequent service processes of the cold-recycling mixture, the compactness of the cold-recycling mixture is improved, and the performance of the emulsified asphalt cold-recycling mixture is further improved.
The invention also provides a preparation method of the emulsified asphalt plant-mixed cold-recycled asphalt mixture, and the emulsified asphalt plant-mixed cold-recycled asphalt mixture is obtained by mixing the components in a mixing manner.
Further, the preparation method specifically comprises the following steps:
step S1: primarily selecting RAP materials, and dividing the RAP materials into four RAP materials according to particle sizes: the composite material comprises a first RAP material, a second RAP material, a third RAP material and a fourth RAP material, wherein the particle size range of the first RAP material is 0.075-4.75 mm, the particle size range of the second RAP material is 4.75-9.5 mm, the particle size range of the third RAP material is 9.5-16 mm, and the particle size range of the fourth RAP material is 16-26.5 mm; then, proportioning according to the mass parts of 20-35 parts of first RAP material, 14-27 parts of second RAP material, 9-23 parts of third RAP material and 5-18 parts of fourth RAP material to obtain a test RAP material;
step S2: treating the test RAP material obtained in the step S1 according to a centrifugal separation method and a rotary evaporator method in JTG E20-2011 test procedures for road engineering asphalt and asphalt mixtures, measuring the content of the old asphalt on the surface of the RAP material and recovering the old asphalt on the surface;
and step S3: testing the old surface recycled asphalt obtained in the step S2 according to penetration, softening point, rotary viscosity and dynamic shear rheological method in JTG E20-2011 road engineering asphalt and asphalt mixture test regulation, and measuring rut factor data represented by penetration, softening point and Brookfield rotary viscosity at 25 ℃ and G/sin delta at 55 ℃;
and step S4: if the surface recycled old asphalt data obtained in the step S3 meets the following requirements: the penetration at 25 ℃ is more than or equal to 17dmm, the softening point is less than or equal to 70 ℃, the Brookfield rotational viscosity at 135 ℃ is less than or equal to 3500mPa & S, and the rutting factor represented by G x/sin delta at 55 ℃ is less than or equal to 150kPa, and then the step S5 is carried out according to the proportion of the RAP material to be tested meeting the formula requirement; otherwise, the old asphalt on the surface of the RAP material has little contribution to the low-temperature performance of the cold-recycling mixture, and is not suitable for the pavement with higher low-temperature performance requirement, the step S1 is repeated to select the RAP material again, and then the operations of the steps S2 and S3 are carried out until the data of the old asphalt recycled on the surface meet the following requirements: the penetration degree at 25 ℃ is more than or equal to 17dmm, the softening point is less than or equal to 70 ℃, the Brookfield rotational viscosity at 135 ℃ is less than or equal to 3500mPa & s, and the rutting factor represented by G x/sin delta at 55 ℃ is less than or equal to 150kPa;
step S5: and (5) enabling the performance index of the surface recycled old asphalt in the step (S4) to meet a RAP material formula with a penetration degree of more than or equal to 17dmm at 25 ℃, a softening point of less than or equal to 70 ℃, a Brookfield rotary viscosity of less than or equal to 3500mPa & S at 135 ℃ and a rutting factor of less than or equal to 150kPa represented by G & ltx/sin & delta & gt at 55 ℃, and being used for preparing the cold recycled asphalt mixture of the emulsified asphalt plant mixing plant, wherein the detailed preparation method comprises the following steps: pouring the third RAP material, the fourth RAP material and the new aggregate into a mixing pot together according to the mixing proportion, firstly adding water accounting for 1/4 of the total water consumption and emulsified asphalt accounting for 1/3 of the total emulsified asphalt consumption, and mixing for 60s to uniformly wrap the materials; then manually mixing the first RAP material and the second RAP material with the rest water to wet the surface of the fine aggregate, putting the fine aggregate into a mixing pot, pouring the rest emulsified asphalt into the mixing pot, and mixing for 60 seconds; and finally, adding cement and filler to mix for 60s, so that the mixture is uniform and stable and has consistent color, and the plant-mixed cold recycled asphalt mixture of the emulsified asphalt is obtained.
Compared with the prior art, the invention has the following beneficial effects: the physical rheological index of the recycled old asphalt on the surface of the RAP material is limited, so that the old asphalt on the surface is ensured to be in a certain aging degree, the improvement effect of the old asphalt on the low-temperature cracking resistance of the cold-recycling mixture is effectively ensured, meanwhile, the void ratio of the cold-recycling mixture is reduced, better overall performance is favorably obtained, and the reasonable utilization of the RAP material in the emulsified asphalt cold-recycling mixture is further perfected.
Detailed Description
For a better understanding of the present invention, the following further illustrates the contents of the invention in connection with its practice, but the contents of the invention are not limited to the following examples. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.
In the following examples and comparative examples, the new aggregate is limestone, 9.5 to 19mm; the RAP materials come from milling materials (named as L1, L2, L3 and L4 respectively) of expressways with different service life, the aging degrees of the surface recovered old asphalt are different, the RAP materials are divided into four grades, and the RAP materials are divided into a first RAP material (0.075-4.75 mm), a second RAP material (4.75-9.5 mm), a third RAP material (4.75-9.5 mm) and a fourth RAP material (16-26.5 mm) according to the particle size range; the filler is limestone mineral powder; the emulsified asphalt is cation slow-cracking emulsified asphalt; the water is domestic water; the cement is ordinary portland cement, the label is P.O 42.5, and the fineness is 80 mu m.
Comparative examples 1 to 1
The RAP material is prepared by adopting milling material of an expressway L1, 25 parts of a first RAP material, 15 parts of a second RAP material, 16 parts of a third RAP material and 14 parts of a fourth RAP material are weighed, the fourth RAP material is mixed according to a ratio and aged in a blast oven at 65 ℃ for 9 days, then the aged RAP material is recycled according to road engineering asphalt and asphalt mixture test procedures (JTG E20-2011) of China industrial standards, the content of old asphalt is measured to be 4.7%, and physical rheological indexes (Brinell rotation viscosity at 135 ℃ and rut factor at 55 ℃) of the old asphalt are measured, and the results are shown in Table 1. In addition, 15 parts of new aggregate, 4.5 parts of mineral powder, 4.4 parts of emulsified asphalt, 4.3 parts of water and 1.8 parts of cement are weighed, a Marshall test piece is formed according to the technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and the test procedure for road engineering asphalt and asphalt mixtures (JTG E20-2011), the test mold is taken out after being cured for 42 hours in a blast oven at the temperature of 60 ℃, the test mold is cooled for 12 hours at room temperature and then is demoulded, and the voidage and the low-temperature failure strain at the temperature of minus 10 ℃ are measured and shown in Table 1.
Comparative examples 1 to 2
The RAP material is prepared by adopting milling material of an expressway L1, 25 parts of a first RAP material, 15 parts of a second RAP material, 16 parts of a third RAP material and 14 parts of a fourth RAP material are weighed, the fourth RAP material is mixed according to a ratio and aged in a blast oven at 65 ℃ for 6 days, then the aged RAP material is recycled according to road engineering asphalt and asphalt mixture test procedures (JTG E20-2011) of China industrial standards, the content of the old asphalt is measured to be 4.7%, and physical rheological indexes (Brinell rotation viscosity at 135 ℃ and rut factor at 55 ℃) of the old asphalt are measured, and the results are shown in Table 1. In addition, 15 parts of new aggregate, 4.5 parts of mineral powder, 4.4 parts of emulsified asphalt, 4.3 parts of water and 1.8 parts of cement are weighed, a Marshall test piece is formed according to the technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and the test procedure for road engineering asphalt and asphalt mixtures (JTG E20-2011), the test mold is taken out after being cured for 42 hours in a blast oven at the temperature of 60 ℃, the test mold is cooled for 12 hours at room temperature and then is demoulded, and the voidage and the low-temperature failure strain at the temperature of minus 10 ℃ are measured and shown in Table 1.
Examples 1 to 1
The RAP material is prepared by adopting milling material of an expressway L1, 25 parts of a first RAP material, 15 parts of a second RAP material, 16 parts of a third RAP material and 14 parts of a fourth RAP material are weighed, the fourth RAP material is mixed according to a ratio and aged in a blast oven at 65 ℃ for 3 days, then the aged RAP material is recycled according to road engineering asphalt and asphalt mixture test procedures (JTG E20-2011) of China industrial standards, the content of old asphalt is measured to be 4.8%, and physical rheological indexes (Brinell rotation viscosity at 135 ℃ and rut factor at 55 ℃) of the old asphalt are measured, and the results are shown in Table 1. In addition, 15 parts of new aggregate, 4.5 parts of mineral powder, 4.4 parts of emulsified asphalt, 4.3 parts of water and 1.8 parts of cement are weighed, marshall test pieces are formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixtures (JTG E20-2011), the test molds are taken out after being cured for 42 hours in a blast oven at 60 ℃, the test molds are cooled for 12 hours at room temperature and then are demoulded, and the voidage and the low-temperature failure strain at minus 10 ℃ are measured and shown in Table 1.
Examples 1 to 2
The RAP material is prepared by adopting milling and planing material of a highway L1, weighing 25 parts of a first RAP material, 15 parts of a second RAP material, 16 parts of a third RAP material and 14 parts of a fourth RAP material, mixing the four RAP materials according to a ratio according to the national industry standard road engineering asphalt and asphalt mixture test specification (JTG E20-2011), recovering the old asphalt, measuring the content of the old asphalt to be 4.8%, and testing the physical rheological indexes (penetration at 25 ℃, softening point, brookfield rotary viscosity at 135 ℃ and rutting factor (G x/sin delta) at 55 ℃) of the old asphalt, wherein the results are shown in Table 1. In addition, 15 parts of new aggregate, 4.5 parts of mineral powder, 4.4 parts of emulsified asphalt, 4.3 parts of water and 1.8 parts of cement are weighed, marshall test pieces are formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixtures (JTG E20-2011), the test molds are taken out after being cured for 42 hours in a blast oven at 60 ℃, the test molds are cooled for 12 hours at room temperature and then are demoulded, and the voidage and the low-temperature failure strain at minus 10 ℃ are measured and shown in Table 1.
Comparative example 2
The RAP material is prepared from milling materials of a highway L2, 23 parts of a first RAP material, 15 parts of a second RAP material, 15 parts of a third RAP material and 16 parts of a fourth RAP material are weighed, the four RAP materials are mixed according to a ratio and aged in a blast oven at 65 ℃ for 6 days, then the aged RAP materials are recycled according to the highway engineering asphalt and asphalt mixture test specification (JTG E20-2011) of the national industry standard, the content of old asphalt is measured to be 4.5%, and physical rheological indexes (25 ℃ penetration, softening point, 135 ℃ rut rotary viscosity and 55 ℃ car Brinell factor) of the old asphalt are measured, and the results are shown in Table 1. In addition, 17 parts of new aggregate, 3.9 parts of mineral powder, 4.2 parts of emulsified asphalt, 4.5 parts of water and 1.4 parts of cement are weighed, marshall test pieces are formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixtures (JTG E20-2011), the test molds are taken out after being cured for 42 hours in a blast oven at 60 ℃, the test molds are cooled for 12 hours at room temperature and then are demoulded, and the voidage and the low-temperature failure strain at minus 10 ℃ are measured and shown in Table 1.
Example 2-1
The RAP material is prepared from milling materials of a highway L2, 23 parts of a first RAP material, 15 parts of a second RAP material, 15 parts of a third RAP material and 16 parts of a fourth RAP material are weighed, the four RAP materials are mixed according to a ratio and aged in a blast oven at 65 ℃ for 3 days, then the aged RAP materials are recycled according to the highway engineering asphalt and asphalt mixture test specification (JTG E20-2011) of the national industry standard, the content of the old asphalt is measured to be 4.5%, and physical rheological indexes (25 ℃ penetration, softening point, 135 ℃ rut rotary viscosity and 55 ℃ rut Brinell factor) of the old asphalt are measured, and the results are shown in Table 1. In addition, 17 parts of new aggregate, 3.9 parts of mineral powder, 4.2 parts of emulsified asphalt, 4.5 parts of water and 1.4 parts of cement are weighed, marshall test pieces are formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixtures (JTG E20-2011), the test molds are taken out after being cured for 42 hours in a blast oven at 60 ℃, the test molds are cooled for 12 hours at room temperature and then are demoulded, and the voidage and the low-temperature failure strain at minus 10 ℃ are measured and shown in Table 1.
Examples 2 to 2
The RAP material is a milling material of a highway L2, 23 parts of a first RAP material, 15 parts of a second RAP material, 15 parts of a third RAP material and 16 parts of a fourth RAP material are weighed, old asphalt is recycled from the aged RAP material according to the Highway engineering asphalt and asphalt mixture test specification (JTG E20-2011) of the national industry standard, the content of the old asphalt is measured to be 4.4%, and physical rheological indexes (penetration, softening point, brinell rotary viscosity at 135 ℃ and rutting factor at 55 ℃) of the old asphalt are measured, and the results are shown in table 1. In addition, 17 parts of new aggregate, 3.9 parts of mineral powder, 4.2 parts of emulsified asphalt, 4.5 parts of water and 1.4 parts of cement are weighed, marshall test pieces are formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixtures (JTG E20-2011), the test molds are taken out after being cured for 42 hours in a blast oven at 60 ℃, the test molds are cooled for 12 hours at room temperature and then are demoulded, and the voidage and the low-temperature failure strain at minus 10 ℃ are measured and shown in Table 1.
Comparative example 3-1
The RAP material is prepared by adopting milling material of an expressway L3, 29 parts of a first RAP material, 17 parts of a second RAP material, 16 parts of a third RAP material and 9 parts of a fourth RAP material are weighed, the fourth RAP material is mixed according to a ratio and aged in a blast oven at 65 ℃ for 6 days, then the aged RAP material is recycled according to road engineering asphalt and asphalt mixture test procedures (JTG E20-2011) of China industrial standards, the content of the old asphalt is measured to be 4.6%, and physical rheological indexes (Brinell rotation viscosity at 135 ℃ and rut factor at 55 ℃) of the old asphalt are measured, and the results are shown in Table 1. In addition, 15 parts of new aggregate, 4 parts of mineral powder, 4.3 parts of emulsified asphalt, 4.3 parts of water and 1.4 parts of cement are weighed, a Marshall test piece is formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixtures (JTG E20-2011), the test mould is taken out after being cured for 42 hours in a blast oven at the temperature of 60 ℃, the test mould is cooled for 12 hours at room temperature and then is demoulded, and the voidage and the low-temperature failure strain at the temperature of-10 ℃ are measured and shown in Table 1.
Comparative examples 3 and 2
The RAP material is prepared from a milling material of a highway L3 by weighing 29 parts of a first RAP material, 17 parts of a second RAP material, 16 parts of a third RAP material and 9 parts of a fourth RAP material, mixing the four RAP materials according to a ratio, aging in a blast oven at 65 ℃ for 3 days, recycling the aged RAP material according to the road engineering asphalt and asphalt mixture test specification (JTG E20-2011) of the national industry standard, measuring the content of the old asphalt to be 4.6%, and testing physical rheological indexes (25 ℃ penetration, softening point, 135 ℃ rut rotary viscosity and 55 ℃ turning Brinell factor) of the old asphalt, wherein the results are shown in Table 1. In addition, 15 parts of new aggregate, 4 parts of mineral powder, 4.3 parts of emulsified asphalt, 4.3 parts of water and 1.4 parts of cement are weighed, a Marshall test piece is formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixture (JTG E20-2011), the test mould is taken out after being cured for 42 hours in a blast oven at 60 ℃, the test mould is demoulded after being cooled for 12 hours at room temperature, and the porosity and the low-temperature failure strain at-10 ℃ are measured and shown in Table 1.
Example 3
The RAP material is prepared by adopting milling material of an expressway L3, 29 parts of a first RAP material, 17 parts of a second RAP material, 16 parts of a third RAP material and 9 parts of a fourth RAP material are weighed, the aged RAP materials are recycled according to the road engineering asphalt and asphalt mixture test procedure (JTG E20-2011) of the national industry standard, the content of the old asphalt is measured to be 4.6%, and physical rheological indexes (penetration, softening point, brinell rotary viscosity at 135 ℃ and rutting factor at 55 ℃) of the old asphalt are tested, and the results are shown in Table 1. In addition, 15 parts of new aggregate, 4 parts of mineral powder, 4.3 parts of emulsified asphalt, 4.3 parts of water and 1.4 parts of cement are weighed, a Marshall test piece is formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixture (JTG E20-2011), the test mould is taken out after being cured for 42 hours in a blast oven at 60 ℃, the test mould is demoulded after being cooled for 12 hours at room temperature, and the porosity and the low-temperature failure strain at-10 ℃ are measured and shown in Table 1.
Comparative example 4-1
The RAP material is prepared by adopting milling material of an expressway L4, weighing 23 parts of a first RAP material, 22 parts of a second RAP material, 11 parts of a third RAP material and 16 parts of a fourth RAP material, recycling the aged RAP material according to the road engineering asphalt and asphalt mixture test procedure (JTG E20-2011) of the national industry standard, measuring the content of the old asphalt to be 4.2%, and testing the physical rheological indexes (penetration, softening point, brinell rotary viscosity at 135 ℃ and rutting factor at 55 ℃) of the old asphalt, wherein the results are shown in Table 1. In addition, 15 parts of new aggregate, 4 parts of mineral powder, 4.4 parts of emulsified asphalt, 3.4 parts of water and 1.2 parts of cement are weighed, a Marshall test piece is formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixture (JTG E20-2011), the test mould is taken out after being cured for 42 hours in a blast oven at 60 ℃, the test mould is demoulded after being cooled for 12 hours at room temperature, and the porosity and the low-temperature failure strain at-10 ℃ are measured and shown in Table 1.
Comparative examples 4 and 2
The RAP material is prepared from a milling material of a highway L4 by weighing 23 parts of a first RAP material, 22 parts of a second RAP material, 11 parts of a third RAP material and 16 parts of a fourth RAP material, mixing the four RAP materials according to a ratio, aging in a blast oven at 65 ℃ for 3 days, recycling the aged RAP material according to the road engineering asphalt and asphalt mixture test specification (JTG E20-2011) of the national industry standard, measuring the content of the old asphalt to be 4.2%, and testing physical rheological indexes (25 ℃ penetration, softening point, 135 ℃ rut rotary viscosity and 55 ℃ Brinell factor) of the old asphalt, wherein the results are shown in Table 1. In addition, 15 parts of new aggregate, 4 parts of mineral powder, 4.4 parts of emulsified asphalt, 3.4 parts of water and 1.2 parts of cement are weighed, a Marshall test piece is formed according to technical Specification for road asphalt pavement regeneration (JTG/T5521-2019) and test procedure for road engineering asphalt and asphalt mixture (JTG E20-2011), the test mould is taken out after being cured for 42 hours in a blast oven at 60 ℃, the test mould is demoulded after being cooled for 12 hours at room temperature, and the porosity and the low-temperature failure strain at-10 ℃ are measured and shown in Table 1.
As can be seen from Table 1, for RAP materials of four different highways, the aging degree is deepened along with the control of the days of the RAP materials aging in a blast oven at a specified temperature, the penetration degree at 25 ℃ of the corresponding recovered old asphalt is obviously reduced, and the softening point, the Brookfield rotary viscosity at 135 ℃ and the rutting factor at 55 ℃ are obviously increased. At the same time, the void fraction of the corresponding emulsified asphalt cold-recycled mix increases and the low temperature failure strain decreases. When the penetration degree at 25 ℃ is more than or equal to 17dmm, the softening point is less than or equal to 70 ℃, the Brookfield rotational viscosity at 135 ℃ is less than or equal to 3500mPa & s, and the rutting factor at 55 ℃ is less than or equal to 150kPa, the increase of the void ratio and the reduction of the low-temperature failure strain are relatively small; however, when the penetration at 25 ℃ is less than 17dmm, the softening point is more than 70 ℃, the Brookfield rotary viscosity at 135 ℃ is more than 3500mPa & s, and the rutting factor at 55 ℃ is more than 150kPa, the increase of the void ratio and the reduction of the low-temperature failure strain are obviously increased.
TABLE 1 voidage and-10 ℃ Low temperature Indirect tensile failure Strain
Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.
Claims (3)
1. The plant-mixed cold recycled asphalt mixture of the emulsified asphalt is characterized by comprising an RAP material, new aggregates, a filler, emulsified asphalt, water and cement;
the raw materials are as follows in parts by mass:
64 to 77 portions of RAP material, 9 to 23 portions of new aggregate, 3 to 5.5 portions of filler, 3 to 5 portions of emulsified asphalt, 3 to 5 portions of water and 0.5 to 2 portions of cement;
the RAP material is an expressway milling material and comprises a first RAP material, a second RAP material, a third RAP material and a fourth RAP material, the particle size range of the first RAP material is 0.075-4.75 mm, the particle size range of the second RAP material is 4.75-9.5 mm, the particle size range of the third RAP material is 9.5-16 mm, and the particle size range of the fourth RAP material is 16-26.5 mm;
the RAP material comprises the following components in parts by mass: 20-35 parts of first RAP material, 14-27 parts of second RAP material, 9-23 parts of third RAP material and 5-18 parts of fourth RAP material;
the content of the recycled old asphalt on the surface of the RAP material accounts for 3.9-5.5% of the mass percent of the RAP material; the surface recycled old asphalt has the following properties: the penetration degree at 25 ℃ is more than or equal to 17dmm, the softening point is less than or equal to 70 ℃, the Brookfield rotational viscosity at 135 ℃ is less than or equal to 3500mPa & s, and the rutting factor characterized by G & ltx/sin & delta & gt at 55 ℃ is less than or equal to 150kPa;
the new aggregate is limestone with the particle size range of 9.5-19 mm; the filler is limestone mineral powder; the emulsified asphalt is cation slow-cracking emulsified asphalt; the cement is ordinary portland cement.
2. The method for preparing the emulsified asphalt plant-mixed cold-recycled asphalt mixture according to claim 1, wherein the emulsified asphalt plant-mixed cold-recycled asphalt mixture is obtained by mixing the components in a mixing manner.
3. The preparation method of the emulsified asphalt plant-mixed cold-recycled asphalt mixture according to claim 2, which is characterized by comprising the following steps:
step S1: primarily selecting RAP materials, and dividing the RAP materials into four RAP materials according to particle sizes: the composite material comprises a first RAP material, a second RAP material, a third RAP material and a fourth RAP material, wherein the particle size range of the first RAP material is 0.075-4.75 mm, the particle size range of the second RAP material is 4.75-9.5 mm, the particle size range of the third RAP material is 9.5-16 mm, and the particle size range of the fourth RAP material is 16-26.5 mm; then, proportioning according to the mass parts of 20-35 parts of first RAP material, 14-27 parts of second RAP material, 9-23 parts of third RAP material and 5-18 parts of fourth RAP material to obtain a test RAP material;
step S2: treating the test RAP material obtained in the step S1 according to a centrifugal separation method and a rotary evaporator method in JTG E20-2011 test procedures for road engineering asphalt and asphalt mixtures, measuring the content of the old asphalt on the surface of the RAP material and recovering the old asphalt on the surface;
and step S3: testing the surface recycled old asphalt obtained in the step S2 according to a penetration, a softening point, a rotary viscosity and a dynamic shear rheological method in JTG E20-2011 road engineering asphalt and asphalt mixture test specification, and measuring rut factor data characterized by the penetration, the softening point, the Brookfield rotary viscosity at the temperature of 25 ℃ and G/sin delta at the temperature of 55 ℃;
and step S4: if the surface recycled old asphalt data obtained in the step S3 meets the following requirements: the penetration at 25 ℃ is more than or equal to 17dmm, the softening point is less than or equal to 70 ℃, the Brookfield rotational viscosity at 135 ℃ is less than or equal to 3500mPa & S, and the rutting factor represented by G x/sin delta at 55 ℃ is less than or equal to 150kPa, and then the step S5 is carried out according to the proportion of the RAP material to be tested meeting the formula requirement; otherwise, the old asphalt on the surface of the RAP material has little contribution to the low-temperature performance of the cold-recycling mixture, is not suitable for the pavement with higher low-temperature performance requirement, the RAP material needs to be selected again by repeating the step S1, and then the operations of the steps S2 and S3 are carried out until the data of the old asphalt recovered on the surface meet the following conditions: the penetration degree at 25 ℃ is more than or equal to 17dmm, the softening point is less than or equal to 70 ℃, the Brookfield rotational viscosity at 135 ℃ is less than or equal to 3500mPa & s, and the rutting factor represented by G x/sin delta at 55 ℃ is less than or equal to 150kPa;
step S5: and (3) enabling the performance indexes of the surface recycled old asphalt in the step (S4) to meet an RAP material formula with a penetration degree of more than or equal to 17dmm at 25 ℃, a softening point of less than or equal to 70 ℃, a Brookfield rotary viscosity of less than or equal to 3500mPa & S at 135 ℃ and a rutting factor represented by G & ltx/sin & delta & gt at 55 ℃ of less than or equal to 150kPa, and preparing the cold recycled asphalt mixture of the emulsified asphalt plant mix, wherein the detailed preparation method comprises the following steps: pouring the third RAP material, the fourth RAP material and the new aggregate into a mixing pot together according to the mixing proportion, firstly adding water accounting for 1/4 of the total water consumption and emulsified asphalt accounting for 1/3 of the total emulsified asphalt consumption, and mixing for 60s to uniformly wrap the materials; then manually mixing the first RAP material and the second RAP material with the rest water to wet the surface of the fine aggregate, putting the fine aggregate into a mixing pot, pouring the rest emulsified asphalt into the mixing pot, and mixing for 60 seconds; and finally, adding cement and filler to mix for 60s, so that the mixture is uniform and stable and has consistent color, and the plant-mixed cold recycled asphalt mixture of the emulsified asphalt is obtained.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210351981.9A CN114804760B (en) | 2022-04-02 | 2022-04-02 | Emulsified asphalt plant-mixed cold recycled asphalt mixture and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210351981.9A CN114804760B (en) | 2022-04-02 | 2022-04-02 | Emulsified asphalt plant-mixed cold recycled asphalt mixture and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114804760A CN114804760A (en) | 2022-07-29 |
| CN114804760B true CN114804760B (en) | 2022-12-02 |
Family
ID=82533148
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210351981.9A Active CN114804760B (en) | 2022-04-02 | 2022-04-02 | Emulsified asphalt plant-mixed cold recycled asphalt mixture and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114804760B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115504718A (en) * | 2022-10-17 | 2022-12-23 | 广州公路工程集团有限公司 | Regeneration method of asphalt mixture |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2009101336A4 (en) * | 2009-12-22 | 2010-02-25 | Jiangxi Ganyue Expressway Co Ltd | Cold-recycling emulsified asphalt mixture and method for pavement reconstruction |
| CN102503245B (en) * | 2011-10-25 | 2013-05-15 | 华南理工大学 | Cold reclaimed asphalt mixing material and normal-temperature emulsified reclaiming method thereof |
| CN103821062B (en) * | 2014-03-11 | 2015-08-26 | 扬州大学 | Old asphalt pavement cementitious matter classify and grading renovation process |
| CN104402316B (en) * | 2014-11-02 | 2016-05-18 | 长安大学 | A kind of mixing proportion design method of Cold Recycled Mixture with Emulsified Asphalt |
| CN113563031A (en) * | 2021-08-18 | 2021-10-29 | 中交路桥华南工程有限公司 | Preparation method of emulsified asphalt cold-recycling mixture |
| CN113636786B (en) * | 2021-10-18 | 2021-12-17 | 湖南大学 | Emulsified asphalt plant-mixed cold recycled asphalt mixture and preparation method thereof |
| CN114163187A (en) * | 2021-11-24 | 2022-03-11 | 汇通建设集团股份有限公司 | Emulsified asphalt plant-mixed cold-recycling mixture and construction process thereof |
-
2022
- 2022-04-02 CN CN202210351981.9A patent/CN114804760B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN114804760A (en) | 2022-07-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| AU2004220301B2 (en) | Bituminous binder and method for the production thereof | |
| WO2019129148A1 (en) | Modified asphalt and preparation method therefor | |
| WO2012103691A1 (en) | Road asphalt modified by composite modifier and preparation method thereof | |
| CN109650781B (en) | Medium-low temperature warm-mixed high-friction thin-layer overlay asphalt mixture and preparation method thereof | |
| CN111377661B (en) | Ultrathin asphalt mixture based on environment-friendly rubber powder and preparation method thereof | |
| CN112960941B (en) | Warm-mixed recycled asphalt mixture, and modified preparation method and application thereof | |
| CN108559289B (en) | Nano modified emulsified asphalt and preparation and use methods thereof | |
| CN112029306A (en) | Preparation method of epoxy modified emulsified asphalt with shape memory performance | |
| KR102159995B1 (en) | Drainable asphalt composition and construction methods using thereof | |
| CN114804760B (en) | Emulsified asphalt plant-mixed cold recycled asphalt mixture and preparation method thereof | |
| CN109267452B (en) | Mixture based on cold regeneration of pavement reclaimed materials and preparation method and application thereof | |
| Prastanto et al. | Study of physical characteristic of rubberized hot mix asphalt based on various dosage of natural rubber latex and solid rubber | |
| CN115124282B (en) | Asphalt pavement old material recycling mixture based on SBS and epoxy resin system and preparation method thereof | |
| CN110903059A (en) | Super-viscous wear-resistant composite modified emulsified asphalt thin layer cover material and preparation method thereof | |
| Shaffie et al. | Investigation on rutting performance of nanopolyacrylate and natural rubber latex polymer modified asphalt binder mixes | |
| CN107902959B (en) | Asphalt loss layer and preparation method and application thereof | |
| Xia et al. | Road performance comprehensive evaluation of polymer modified emulsified asphalt fiber microsurfacing | |
| CN113622247B (en) | Low-carbon rapid maintenance paving method for asphalt pavement track | |
| CN113149534A (en) | Anti-rutting asphalt and preparation method thereof | |
| CN106673504B (en) | A kind of room temperature mix bitumen concrete and preparation method thereof | |
| CN113480240B (en) | Asphalt concrete and preparation method thereof | |
| KR102242826B1 (en) | Wet type high performance modified asphalt binder and asphalt composition using same | |
| CN117534420B (en) | Asphalt pavement repair material | |
| CN113831081B (en) | Asphalt/cement composite base normal-temperature self-compacting asphalt concrete and preparation method thereof | |
| CN116535136B (en) | Plant-mixed hot regenerated epoxy asphalt mixture and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |