Method and system for rapidly testing caking rate of asphalt mixture

Abstract

The invention relates to the technical field of road engineering material detection, in particular to a method and system for rapidly testing the caking rate of an asphalt mixture, asphalt mixture recycled materials are obtained through cold milling and planing, drying treatment is conducted, and then asphalt and aggregate are separated through a separation method; the separated aggregate is screened through a standard screen, and the weight of the aggregate is recorded; the volume of the recycled material is measured through the three-dimensional scanning volume measuring and calculating device, and finally the caking rate is calculated according to the measured volume and weight. The method can rapidly and accurately evaluate the caking rate of the recycled asphalt mixture, shortens the test period, improves the test precision, and is suitable for quality control and construction site detection of recycled asphalt mixture production.

Description

Technical Field

[0001] The invention relates to the technical field of road engineering material detection, and in particular to a method and system for quickly testing the agglomeration rate of asphalt mixture. Background Art

[0002] With the development of modern transportation, the recycling of asphalt pavement has become an important research direction for environmental protection and economy. Especially under the "dual carbon" goal, the use of recycled asphalt mixture is becoming more and more widespread. However, the agglomeration phenomenon of recycled asphalt mixture will seriously affect its recycling performance. Agglomeration refers to the formation of lumps between old asphalt and aggregate in the recycled asphalt mixture during the recycling process, which makes it difficult for the new and old asphalt to fully blend, thus affecting the uniformity and road performance of the recycled asphalt mixture. Therefore, quickly and accurately testing the agglomeration rate of recycled asphalt mixture has become a key link in evaluating the quality of recycled asphalt mixture.

[0003] In the prior art, the main methods for evaluating the agglomeration rate of recycled asphalt mixtures include extraction and combustion. The extraction method uses an organic solvent (such as trichloroethylene) to separate asphalt from aggregates, and then calculates the agglomeration rate through screening and weight analysis. The combustion method separates asphalt from aggregates through high-temperature incineration and then screens. Although these two methods can achieve the separation of asphalt from aggregates, they have the following problems:

[0004] The extraction method requires multiple steps, including dissolution, centrifugation and filtration. The whole process is time-consuming, complicated to operate, and has high requirements for laboratory equipment. The combustion method requires high-temperature treatment, so the entire test cycle is long and it is difficult to meet the needs of on-site instant testing. Since manual operations account for a large proportion, the test results are easily affected by the skills of the operator, and it is difficult to ensure the repeatability and stability of the results. Existing methods usually require a large sample size and a large amount of reagents, resulting in a waste of resources. Summary of the invention

[0005] In view of the many problems existing in the above-mentioned prior art, the present invention provides a method and system for quickly testing the agglomeration rate of asphalt mixture. The present invention obtains asphalt mixture recycled material by cold milling, then dries it and separates asphalt and aggregate, and uses a standard sieve to screen the aggregate and record the weight. The volume of the recycled material is tested by a three-dimensional scanning volume measurement device, and the agglomeration rate is finally calculated based on the volume and weight. This solution simplifies the test process, shortens the test time through automation technology, significantly improves the test accuracy, and solves the problems of complex operation and unstable results in the prior art.

[0006] like Figure 1 As shown, a method for quickly testing the agglomeration rate of asphalt mixture comprises the following steps:

[0007] Obtaining asphalt mixture recycled material, obtaining the asphalt mixture recycled material from an asphalt pavement by a cold milling method;

[0008] Drying the recycled asphalt mixture until the weight of the recycled asphalt mixture reaches a constant;

[0009] Separating asphalt from aggregates, separating asphalt from aggregates in the asphalt mixture recycled material by a separation method;

[0010] Screening the aggregates, screening the separated aggregates through a standard sieve, and recording the weights of the aggregates on the sieve and the aggregates under the sieve;

[0011] The agglomeration rate is calculated based on the measured volume and weight of the recycled asphalt mixture, and the agglomeration rate of the recycled asphalt mixture is calculated. The agglomeration rate is the ratio of the volume of the asphalt to the total volume of the recycled asphalt mixture.

[0012] Preferably, the milling speed of the cold milling method is 10 m / min to 20 m / min.

[0013] Preferably, the milling speed is preferably 15 m / min to reduce the agglomeration rate of the asphalt mixture recycled material.

[0014] Preferably, the temperature of the drying treatment is controlled at 60° C. to 90° C., and the drying time is 2 hours to 4 hours, until the weight of the recycled asphalt mixture reaches a constant.

[0015] Preferably, the step of separating asphalt and aggregate in the asphalt mixture recycled material comprises:

[0016] dissolving the asphalt from the asphalt mixture reclaimed material by using trichloroethylene solvent by an extraction method;

[0017] Alternatively, the asphalt mixture recycled material is burned in a combustion furnace at a temperature not lower than 500° C. until the asphalt is separated from the aggregate.

[0018] Preferably, the step of screening the aggregate comprises screening the separated aggregate using a 2.36 mm standard sieve, and recording the weight of the aggregate on the sieve and the weight of the aggregate under the sieve.

[0019] Preferably, the agglomeration rate is calculated by the following formula:

[0020]

[0021] Among them, V a represents the volume of the asphalt, in cubic centimeters; V represents the total volume of the recycled asphalt mixture, in cubic centimeters.

[0022] Preferably, the volume V of the asphalt a Calculated by the following formula:

[0023]

[0024] Wherein, m represents the mass of the asphalt, in grams; ρ represents the relative density of the asphalt.

[0025] Preferably, the total volume V is measured by a three-dimensional scanning volume measuring device, which is used to test the volume of the recycled asphalt mixture.

[0026] like Figure 2 As shown, a system for implementing the method for quickly testing the agglomeration rate of asphalt mixture recycled materials, the system comprising:

[0027] Cold milling unit for obtaining asphalt mix reclaim from asphalt pavement;

[0028] A drying device, used for drying the recycled asphalt mixture to make the weight of the recycled asphalt mixture constant;

[0029] A separation device, used to separate the asphalt from the aggregate in the asphalt mixture reclaimed material, the separation device comprising a trichloroethylene solvent device for extraction separation, or a combustion furnace for combustion separation;

[0030] A screening device, used for screening the separated aggregate through a standard sieve, and recording the weight of the aggregate above the sieve and the aggregate below the sieve;

[0031] A volume measuring device, used to measure the volume of the recycled asphalt mixture;

[0032] The agglomeration rate calculation module is used to calculate the agglomeration rate of the recycled asphalt mixture according to the measured volume and weight of the recycled asphalt mixture, and the agglomeration rate is the ratio of the volume of the asphalt to the total volume of the recycled asphalt mixture.

[0033] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0034] The present invention realizes efficient separation of asphalt and aggregate by means of automated separation technology: it combines automated extraction equipment and three-dimensional scanning volume measurement device, simplifies the operation process, avoids errors caused by manual operation, and improves test efficiency;

[0035] The present invention achieves a rapid volume measurement effect through a three-dimensional scanning volume measurement device: the volume of the recycled material can be accurately measured in a short time, the test cycle is shortened, and the demand for rapid detection at the construction site is met;

[0036] The present invention realizes high integration and flexibility of the system through modular design: each functional module can be combined and used according to actual needs, suitable for different construction scenarios, and ensures the flexibility and applicability of the test;

[0037] The present invention achieves the effect of saving resources by reducing the amount of reagents and samples used: compared with the prior art, the present invention significantly reduces the amount of reagents and samples used, thereby reducing the test cost and environmental impact. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the process of the present invention;

[0039] Figure 2 It is a structural block diagram of the system of the present invention;

[0040] Figure 3 A schematic diagram of the steps in the embodiment of the present invention;

[0041] Figure 4 Schematic diagram of three-dimensional scanning volume measurement in an embodiment of the present invention. DETAILED DESCRIPTION

[0042] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is obvious that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0043] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0044] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0045] like Figure 3 As shown, a method for quickly testing the agglomeration rate of asphalt mixture comprises the following steps:

[0046] Step S01: obtaining recycled material of original road surface asphalt mixture;

[0047] There are three ways to obtain the original road asphalt mixture:

[0048] The first method is to use a dedicated coring machine to drill and sample the road section where the asphalt mixture recycled material is obtained, and obtain the core sample of the original pavement structure layer where the asphalt mixture recycled material is located;

[0049] The second method is to use an asphalt pavement hot regeneration repair vehicle to heat the asphalt mixture recycling material in the road section. The heating area is usually 1m 2 After the asphalt pavement is heated and softened, the asphalt pavement is raked loose using a raking tool to obtain the original pavement asphalt mixture recycled material after heating and raking loose;

[0050] The third method: Use special milling equipment to perform cold milling on the road section where the asphalt mixture recycled material is obtained to obtain the original road surface asphalt mixture recycled material;

[0051] The obtained original road surface asphalt mixture recycled materials, including the core sample of the original road surface structure layer, the original road surface asphalt mixture recycled materials after heating and harrowing, and the original road surface asphalt mixture recycled materials obtained by cold milling, are dried to a constant weight in an electric blast drying oven with a drying temperature set at 60-90°C and a drying time of 2-4 hours to remove the moisture in the asphalt mixture recycled materials and set aside after cooling. In addition, for the core sample of the asphalt mixture recycled materials obtained by the first type of core sampling, it is also necessary to manually break the core sample during the heating process to obtain loose asphalt mixture recycled materials.

[0052] For the dried asphalt mixture recycled material obtained by any of the above three schemes, according to the asphalt mixture sampling method recommended by T0701 in the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011), the quartering method is used for sampling, and the sampling weight is 1200-1500g for stand-by use.

[0053] Step S02: separating asphalt and aggregate in the recycled material of the original road surface asphalt mixture;

[0054] The following two methods can be used to separate the asphalt and aggregate of the 1200-1500g recycled asphalt mixture after sampling:

[0055] The first method: According to the T0722 centrifugal separation method in the "Testing Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011), also known as the extraction method, trichloroethylene organic solvent is used to dissolve the asphalt in the asphalt mixture recovery material to achieve the purpose of separating asphalt from aggregate. Usually, a fully automatic asphalt mixture extraction device is used to place the weighed asphalt mixture recovery material in the extraction device in a closed standard screen device composed of 0.075mm, 0.3mm, 0.6mm, 1.18mm, and 2.36mm, and the equipment is operated according to the equipment operating procedures to achieve the separation of asphalt and aggregate in the asphalt mixture. During the test, the trichloroethylene solvent will rinse the asphalt mixture recovery material in the screen device, and a high-speed centrifugal bucket will be used to collect the mineral powder in the filtrate seeping from the screen until there is no asphalt on the surface of the asphalt mixture recovery material. The operation is terminated to obtain the aggregate in the asphalt mixture recovery material.

[0056] The second method: According to the T0735 combustion method in the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011), the asphalt in the recycled asphalt mixture is burned out by high-temperature heating and combustion, leaving only aggregates, so as to achieve the goal of separating aggregates from asphalt in the asphalt mixture. During the test, an asphalt mixture combustion furnace is used. According to the equipment operating procedures, the weighed recycled asphalt mixture is placed in the tray in the combustion furnace, and the furnace temperature of the combustion furnace is set to not less than 500°C. When the quality of the recycled asphalt mixture remains basically unchanged during the combustion process, the operation is terminated to obtain the aggregates in the recycled asphalt mixture.

[0057] To obtain the aggregate in the recycled asphalt mixture according to the above scheme, it is necessary to determine whether repeated tests are needed based on the number of tests using the aggregate, so as to obtain the aggregate weight that meets the requirements of subsequent tests. Usually, the weight of the aggregate in the recycled asphalt mixture obtained is not less than 3000g.

[0058] Step S03: using a standard sieve of 2.36 mm to sieve the aggregate separated from the asphalt, and recording the weight of the aggregate on the sieve and the aggregate under the sieve respectively;

[0059] Since the original road aggregate contains coarse aggregate and fine aggregate, the density test methods of the two aggregates are different. It is necessary to use a standard sieve of 2.36mm to screen the aggregate, and define the aggregate with a size larger than 2.36mm after screening as coarse aggregate, and define the aggregate with a size smaller than 2.36mm after screening as fine aggregate for subsequent density testing. During the implementation process, the weight of aggregate not less than 3000g in the asphalt mixture recycled material is placed on a 2.36mm standard sieve for screening by adding small amounts multiple times, and obtain the coarse aggregate on the sieve and the fine aggregate under the sieve, and record the weight of the aggregate on the sieve and the aggregate under the sieve as m1 and m2 respectively, both in g;

[0060] Step S04: using trichloroethylene to dissolve the asphalt on the surface of the asphalt mixture recovery material, and recovering the asphalt in the trichloroethylene solution;

[0061] The asphalt on the surface of the recycled asphalt mixture is separated from the aggregate by soaking. Specifically, trichloroethylene solvent is used. The amount of trichloroethylene added to the recycled asphalt mixture is 3 to 5 times the volume of the recycled asphalt mixture for soaking. The soaking time is 24 hours. Then the upper liquid level of the trichloroethylene solution after soaking is extracted, which does not exceed 1 / 3 of the total liquid level. The obtained asphalt solution is separated from the asphalt and trichloroethylene solvent according to the rotary evaporator method of T0727 in the "Test Procedure for Asphalt and Asphalt Mixtures for Highway Engineering" (JTG E20-2011) to obtain the asphalt in the recycled asphalt mixture. In order to meet the requirements of subsequent tests, the mass of the recycled asphalt is generally 60 to 100g. According to the target asphalt quality, it is judged whether multiple parallel tests are needed to achieve the target asphalt recovery quality requirements.

[0062] Step S05: testing the apparent relative density of the oversize aggregate and the undersize aggregate, calculating the composite apparent relative density of the oversize aggregate and the undersize aggregate, and testing and calculating the relative density of the recovered asphalt;

[0063] The coarse aggregate on the sieve and the fine aggregate under the sieve obtained in step S03 are divided into four parts to obtain 1200-1500 g of coarse aggregate on the sieve and 250-350 g of fine aggregate under the sieve.

[0064] According to the test steps of T0304 basket method in the "Highway Engineering Aggregate Test Code" (JTG E42-2005), the apparent relative density of coarse aggregate was tested, and the apparent relative density of the coarse aggregate on the sieve was obtained as γ1, which was calculated according to formula 1:

[0065] Formula 1:

[0066]

[0067] Where: m aIndicates the air weight of the dry aggregate used in the test, in g; m w It represents the weight of the dry aggregate used in the test after being immersed in water, in g.

[0068] According to the test steps of T0328 volumetric flask method in the "Highway Engineering Aggregate Test Code" (JTG E42-2005), the apparent relative density of fine aggregate was tested, and the apparent relative density of fine aggregate under the sieve was γ2, which was calculated according to Formula 2:

[0069] Formula 2:

[0070]

[0071] Where: m b Indicates the weight of the dry aggregate used in the test, in g; m c It indicates the total weight of the volumetric flask used in the test after adding water to the design mark, in grams; m d It indicates the total weight of the aggregate, water and volumetric flask in the test after the dry aggregate is added to the volumetric flask and soaked for 24 hours, and then water is added to the designed mark, in g.

[0072] According to the relevant steps of T0705 in the Test Procedure for Asphalt and Asphalt Mixtures for Highway Engineering (JTG E20-2011), the composite apparent relative density γ of coarse and fine aggregates is calculated. g , calculated according to formula 3:

[0073] Formula 3:

[0074]

[0075] According to the asphalt density and relative density test steps of T0603 in the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011), the relative density of asphalt in the recycled asphalt mixture γ a , calculated according to formula 4:

[0076] Formula 4:

[0077]

[0078] In the formula: m3 represents the total weight of the specific gravity bottle and the asphalt sample it contains, in g; m4 represents the weight of the specific gravity bottle, in g; m5 represents the total weight of the specific gravity bottle and the water it contains, in g.

[0079] Step S06: using a three-dimensional scanning volume measurement device to test the volume of the recycled asphalt mixture, and weighing the weight of the recycled asphalt mixture of the measured volume;

[0080] like Figure 4 As shown in the figure, the agglomeration of fine aggregates is not considered in the asphalt mixture recycling material. Therefore, the asphalt mixture recycling material to be tested is first screened using a standard sieve with an aperture of 2.36 mm to obtain the asphalt mixture recycling material with a coarse particle size. After that, the asphalt mixture recycling material is placed on the scanning plane of the three-dimensional scanning volume measurement device to obtain the volume of the asphalt mixture recycling material on the scanning plane, and the total volume of the asphalt mixture recycling material on the scanning plane is calculated.

[0081] The asphalt mixture recycled material on the scanning plane is dried. Since only the weight of the asphalt mixture recycled material is tested, an electric heating blast drying oven can be used in the laboratory for drying at a drying temperature of 90-170°C until the weight of the asphalt mixture recycled material is basically unchanged, and the weight of the asphalt mixture recycled material on the scanning plane is obtained. Alternatively, a microwave oven can be used for heating and drying, which can achieve the purpose of heating and evaporating the moisture in the asphalt mixture recycled material in a relatively short time at the construction site, realize the operation of rapid drying, and obtain the weight of the asphalt mixture recycled material on the scanning plane.

[0082] Generally, the weight of the recycled asphalt mixture on the scanning plane is recommended to be controlled within 500-1500g. Excessive weight will limit the speed of the 3D scanning volume measurement device to test the volume. The volume V of the recycled asphalt mixture is measured by the 3D scanning volume measurement device in cm. 3 During the volume test, the recycled asphalt mixture should be placed on a horizontal flat surface, and the weight m of the recycled asphalt mixture of the test volume V after drying should be weighed in g.

[0083] Step S07: Calculate the agglomeration rate of the recycled asphalt mixture.

[0084] According to the results of various parameters tested in the above steps, the agglomeration rate β of the recycled asphalt mixture is evaluated by calculating the ratio of the asphalt volume in the recycled asphalt mixture to the recycled material volume, and calculated according to Formula 5:

[0085] Formula 5:

[0086]

[0087] Where: V a Indicates the volume of asphalt in the recycled material of asphalt mixture, in cm 3 ; V represents the volume of recycled asphalt mixture measured by 3D scanning volume measurement device, in cm 3 .

[0088] Among them, the volume V of the recycled asphalt mixture tested by a three-dimensional scanning volume measurement device and its weight m after drying satisfy the relationship between formula 6 and formula 7:

[0089] Formula 6:

[0090] V a +V g =V

[0091] Where: V g Indicates the volume of aggregate in recycled asphalt mixture, in cm 3 ;

[0092] Formula 7:

[0093]

[0094] Where: w Indicates the density of water at the test temperature, in g / cm 3 .

[0095] Substituting formula 6 and formula 7 into formula 5, we get formula 8 for calculating the clustering rate β:

[0096] Formula 8:

[0097]

[0098] The testing method and system of the present invention can be used in the cold milling site of asphalt pavement to timely and quickly test the agglomeration rate of asphalt mixture recycled materials under different milling parameters, and be used to select the optimal milling process parameters. It can also be used to evaluate the agglomeration rate of asphalt mixture recycled materials in asphalt mixture mixing plants and determine reasonable crushing and screening process parameters.

[0099] The present invention will be further described below with specific embodiments:

[0100] Example 1

[0101] This embodiment provides a method and system for quickly testing the agglomeration rate of recycled asphalt mixture, which includes the following steps:

[0102] (1) The core samples of the road section were obtained by core sampling. The number of core samples was 8. The 8 core samples were placed in an electric blast drying oven at 80°C for 4 hours to remove the moisture in the core samples. The core samples were manually broken during the heating process to obtain loose asphalt mixture recycling materials, totaling 9000g. The sampling was carried out by the quartering method to obtain 6 samples of the original road surface asphalt mixture recycling materials, and the weight of the asphalt mixture recycling materials in each sample was 1500g.

[0103] (2) The combustion method was adopted, and an asphalt mixture combustion furnace was used. According to the equipment operating procedures, the asphalt and aggregate in the three samples of the original road asphalt mixture recycled materials were separated, and one portion of the weighed asphalt mixture recycled material was placed in the tray in the combustion furnace. The furnace temperature of the combustion furnace was set to 540°C. When the mass of the asphalt mixture recycled material remained basically unchanged during the combustion process, the operation was terminated to obtain the aggregate in the asphalt mixture recycled material. The remaining two portions of asphalt mixture recycled materials were tested according to the above operation to obtain the asphalt mixture recycled materials after the asphalt was removed. Through the test, the total weight of the three portions of asphalt mixture recycled materials after combustion was 4275g.

[0104] (3) Aggregates from the three parts of asphalt mixture recycling materials after combustion were sieved using a standard sieve of 2.36 mm in size. Aggregates were added in small amounts multiple times to place the recycled asphalt mixture on a standard sieve of 2.36 mm for sieving. The coarse aggregate on the sieve and the fine aggregate under the sieve were obtained. The weights of the aggregate on the sieve and the aggregate under the sieve were recorded as m1 and m2, respectively. The test results were 2565 g and 1710 g, respectively.

[0105] (4) The remaining three samples of recycled asphalt mixture were placed in iron barrels and soaked in trichloroethylene. 4000 ml of trichloroethylene was added to each sample for 24 h. The upper layer of the trichloroethylene solution after soaking was extracted, which did not exceed 1 / 3 of the total liquid level. A rotary evaporator was used to separate the asphalt and solvent in the extracted solution to obtain the asphalt in the recycled asphalt mixture. The mass obtained in this test was 100 g.

[0106] (5) The apparent relative density of the aggregate on the sieve was tested by the basket method T0304 in JTG E42-2005. The test results are shown in Table 1. The apparent relative density of the aggregate under the sieve was tested by the volumetric flask method T0328 in JTG E42-2005. The test results are shown in Table 2. The results of the calculated composite apparent relative density of the aggregate are shown in Table 3. The relative density of asphalt was tested by the asphalt density and relative density test T0603 in JTG E20-2011. The test results are shown in Table 4.

[0107] Table 1 Apparent relative density of oversize aggregate

[0108]

[0109]

[0110] Table 2 Apparent relative density of undersize aggregate

[0111]

[0112] Table 3 Synthetic apparent relative density of aggregates

[0113] parameter <![CDATA[m1 / g]]> <![CDATA[m2 / g]]> <![CDATA[γ1]]> <![CDATA[γ2]]> <![CDATA[γ g ]]> result 2565 1710 2.731 2.710 2.723

[0114] Table 4 Relative density of asphalt

[0115]

[0116] (6) The asphalt pavement was milled by cold milling to obtain asphalt mixture recycling materials. During the construction process, the milling speeds of 20m / min, 15m / min, and 10m / min were used to obtain asphalt mixture recycling materials at different milling speeds. The asphalt mixture obtained after milling was screened by a 2.36mm sieve to obtain the coarse asphalt mixture recycling materials on the sieve at the three milling speeds. The weights of the asphalt mixture recycling materials at the three milling speeds were initially weighed to be 1230.4g, 1185.3g, and 1245.9g, respectively. The three types of asphalt mixture recycling materials were placed on the scanning plane, and the three-dimensional scanning volume measurement device was used to test and calculate the total volume of the asphalt mixture recycling materials at the three milling speeds. After that, the asphalt mixture recycling materials were heated by microwave oven on site to remove the moisture in the asphalt mixture recycling materials. The dry mass of the three types of asphalt mixture recycling materials tested under dry conditions was tested. The test results are shown in Table 5.

[0117] Table 5 Volume and weight of recycled asphalt mixture after field testing

[0118] Milling speed <![CDATA[V / cm 3 ]]> m / g 20m / min 593.5 1215.3 15m / min 525.8 1178.4 10m / min 535.4 1230.6

[0119] (7) According to the results of the indoor test, the relative density of aggregates in Table 3, the relative density of asphalt in Table 4, and the density of water at the test temperature are 0.9971 g / cm 3 , combined with the volume and weight results of the recycled asphalt mixture in the field test in Table 5, the agglomeration rate of the recycled asphalt mixture under different milling speeds is calculated and shown in Table 6.

[0120] Table 6 Calculation results of agglomeration rate of recycled asphalt mixture

[0121] Milling speed <![CDATA[V / cm 3 ]]> m / g β / ％ 20m / min 593.5 1215.3 39.4 15m / min 525.8 1178.4 28.0 10m / min 535.4 1230.6 24.6

[0122] Example 2

[0123] This embodiment discloses a method for quickly testing the agglomeration rate of recycled asphalt mixture and the application of the system;

[0124] According to the test results of the agglomeration rate of asphalt mixture recycled materials at different milling speeds in Example 1, the agglomeration rates of asphalt mixture recycled materials at milling speeds of 20m / min, 15m / min, and 10m / min are 39.4%, 28.0%, and 24.6%, respectively, indicating that the faster the milling speed, the higher the agglomeration rate of asphalt mixture recycled materials generated during the asphalt pavement milling process will be, and the more unfavorable the impact on the production and performance of recycled asphalt mixture. However, a lower milling speed will affect the operating efficiency and increase the construction cost. For this reason, according to the changing trend of the agglomeration rate, it is recommended to use a milling speed of 15m / min, at which time the agglomeration rate of asphalt mixture recycled materials is at a relatively low level, and a higher milling speed can be maintained, which basically does not affect the milling operation efficiency.

[0125] The present invention tests the apparent relative density of aggregates and the relative density of asphalt in the recycled materials of the original road asphalt mixture through preliminary indoor tests, and achieves the purpose of quickly evaluating the agglomeration rate of the recycled materials of the asphalt mixture by comparing the difference between the asphalt volume and the aggregate volume in the asphalt mixture. It effectively avoids the large amount of time required for the traditional method of using a large number of indoor tests to evaluate the agglomeration rate, saves the time of waiting for the agglomeration rate test results in the decision-making process during the engineering application process, and has broad application prospects in actual engineering applications.

[0126] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware.

[0127] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A method for quickly testing the agglomeration rate of asphalt mixture, characterized in that: The following steps are involved: Obtaining asphalt mixture recycled material, obtaining the asphalt mixture recycled material from an asphalt pavement by a cold milling method; Drying the recycled asphalt mixture until the weight of the recycled asphalt mixture reaches a constant; Separating asphalt from aggregates, separating asphalt from aggregates in the asphalt mixture recycled material by a separation method; Screening the aggregates, screening the separated aggregates through a standard sieve, and recording the weights of the aggregates on the sieve and the aggregates under the sieve; The agglomeration rate is calculated based on the measured volume and weight of the recycled asphalt mixture, and the agglomeration rate of the recycled asphalt mixture is calculated. The agglomeration rate is the ratio of the volume of the asphalt to the total volume of the recycled asphalt mixture.

2. A method for quickly testing the agglomeration rate of asphalt mixture recycled materials according to claim 1, characterized in that: The milling speed of the cold milling method is 10 m / min to 20 m / min.

3. A method for quickly testing the agglomeration rate of asphalt mixture recycled material according to claim 2, characterized in that: The milling speed is preferably 15 m / min to reduce the agglomeration rate of the asphalt mixture recycling material.

4. A method for quickly testing the agglomeration rate of recycled asphalt mixture according to claim 1, characterized in that: The temperature of the drying treatment is controlled at 60° C. to 90° C., and the drying time is 2 hours to 4 hours, until the weight of the asphalt mixture recycled material reaches a constant.

5. A method for quickly testing the agglomeration rate of recycled asphalt mixture according to claim 1, characterized in that: The step of separating asphalt and aggregate in the asphalt mixture recycled material comprises: dissolving the asphalt from the asphalt mixture reclaimed material by using trichloroethylene solvent by an extraction method; Alternatively, the asphalt mixture recycled material is burned in a combustion furnace at a temperature not lower than 500° C. until the asphalt is separated from the aggregate.

6. A method for quickly testing the agglomeration rate of recycled asphalt mixture according to claim 1, characterized in that: The step of screening the aggregate includes screening the separated aggregate using a 2.36 mm standard sieve, and recording the weight of the aggregate on the sieve and the weight of the aggregate under the sieve.

7. A method for quickly testing the agglomeration rate of recycled asphalt mixture according to claim 1, characterized in that: The agglomeration rate is calculated by the following formula: Among them, V a represents the volume of the asphalt, in cubic centimeters; V represents the total volume of the recycled asphalt mixture, in cubic centimeters.

8. A method for quickly testing the agglomeration rate of recycled asphalt mixture according to claim 7, characterized in that: The volume V of the asphalt a Calculated by the following formula: Wherein, m represents the mass of the asphalt, in grams; and p represents the relative density of the asphalt.

9. A method for quickly testing the agglomeration rate of recycled asphalt mixture according to claim 8, characterized in that: The total volume V is measured by a three-dimensional scanning volume measuring device, which is used to test the volume of the recycled asphalt mixture.

10. A system for implementing the method for quickly testing the agglomeration rate of recycled asphalt mixture according to any one of claims 1 to 9, characterized in that: The system comprises: Cold milling unit for obtaining asphalt mix reclaim from asphalt pavement; A drying device, used for drying the recycled asphalt mixture to make the weight of the recycled asphalt mixture constant; A separation device, used to separate the asphalt from the aggregate in the asphalt mixture reclaimed material, the separation device comprising a trichloroethylene solvent device for extraction separation, or a combustion furnace for combustion separation; A screening device, used for screening the separated aggregate through a standard sieve, and recording the weight of the aggregate above the sieve and the aggregate below the sieve; A volume measuring device, used to measure the volume of the recycled asphalt mixture; The agglomeration rate calculation module is used to calculate the agglomeration rate of the recycled asphalt mixture according to the measured volume and weight of the recycled asphalt mixture, and the agglomeration rate is the ratio of the volume of the asphalt to the total volume of the recycled asphalt mixture.

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