Device and method for testing specific surface area of coarse aggregate
By designing a coarse aggregate specific surface area testing device containing an ultrasonic detector and a temperature control box, the problem of lack of simple testing methods in the prior art is solved, and the precise measurement of the coarse aggregate specific surface area is achieved, and the detection accuracy is improved. Sexual and economical.
Patent Information
- Application Number
- CN202411461782.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-18
- Publication Date
- 2025-01-03
AI Technical Summary
The prior art lacks a simple and effective method to test the specific surface area of coarse aggregates, which affects the construction quality and material cost of asphalt mixtures.
A specific surface area testing device for coarse aggregates including an ultrasonic detector, a detection chamber, a temperature control box and an electronic scale was designed. By mixing the coarse aggregates with asphalt, the ultrasonic detector was used to measure the surface of coarse aggregates in the asphalt mixture. The thickness of the bitumen film, combined with mass and density, calculate the specific surface area.
The precise test of the specific surface area of coarse aggregate is achieved, the accuracy and economicality of the detection results are improved, and the equipment is small in size, making it easy to detect at any time.
Smart Images
Figure CN119246369A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of aggregate specific surface area testing, and in particular relates to a coarse aggregate specific surface area testing device and method. Background Art
[0002] Asphalt mixture is a commonly used pavement material in road engineering. It has the advantages of low noise, good wear resistance, and easy maintenance. The material cost of asphalt mixture includes aggregate cost and asphalt cost. Asphalt is expensive and its dosage is greatly affected by aggregate. Excellent aggregate gradation can improve the performance of asphalt pavement while reducing material cost. The amount of asphalt is closely related to the specific surface area of aggregate. Generally speaking, the larger the specific surface area of aggregate, the higher the oil absorption. Testing the specific surface area of coarse aggregate can quantitatively analyze the oil absorption of aggregates with different particle size ranges, which helps to optimize the gradation of aggregates and control the construction quality and economic cost of asphalt mixture. At present, there are methods such as the Blaine method and the BET method to test the specific surface area of fine aggregate, but there are few simple and complete testing methods for the specific surface area of coarse aggregate. Summary of the invention
[0003] The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art and to provide a coarse aggregate specific surface area testing device and method, which can accurately test the specific surface area of coarse aggregate.
[0004] The present invention is achieved through the following technical solutions: A coarse aggregate specific surface area testing device comprises: an ultrasonic detector, a testing chamber, a temperature control box, an electronic scale and an asphalt mixer; the asphalt mixer is used to mix the coarse aggregate with asphalt to obtain an asphalt mixture; the testing chamber is used to contain the asphalt mixture; the ultrasonic detector is arranged on one side of the testing chamber, and is used to detect the thickness of the asphalt film on the surface of the coarse aggregate in the asphalt mixture in the testing chamber; the temperature control box is used to control the temperature in the testing chamber at the testing temperature; the electronic scale is used to weigh the mass of the coarse aggregate and the asphalt mixture at the testing temperature.
[0005] Preferably, the detection chamber is in the shape of a sphere, and the coarse aggregate specific surface area testing device comprises a driving device, and the driving device is used to drive the detection chamber to rotate.
[0006] Furthermore, the coarse aggregate specific surface area testing device includes a base, and the bottom of the detection chamber passes through the base and is connected to the driving device; a bearing is installed at the intersection of the detection chamber and the base.
[0007] Furthermore, the driving device includes a first motor, a screw module, a second motor, a gear, a rack and a rack sliding groove, the output end of the first motor is connected to one end of the screw of the screw module, and the first displacement plate is threadedly connected to the screw; the second motor and the rack sliding groove are arranged on the first displacement plate, the gear is located above the second motor and is coaxially connected to the output shaft of the second motor, the rack is slidably installed in the rack sliding groove, the gear is meshed with the rack, and the length direction of the rack is perpendicular to the length direction of the screw; the top of the rack is fixedly connected to the second displacement plate, the second displacement plate is placed horizontally, and the bottom of the detection chamber is in contact with the upper surface of the second displacement plate.
[0008] Preferably, the coarse aggregate specific surface area testing device comprises a vacuum pump and a medium collecting barrel; when in use, the top of the detection chamber is connected to the medium collecting barrel via a vacuum tube, and the medium collecting barrel is connected to the vacuum pump via a vacuum tube.
[0009] Preferably, the coarse aggregate specific surface area testing device comprises an ultrasonic detector fixing frame, and the ultrasonic detector is fixed on the ultrasonic detector fixing frame.
[0010] Preferably, the temperature control box is a box-type structure, and the detection chamber and the ultrasonic detector are arranged in the temperature control box.
[0011] The present invention provides a method for testing the specific surface area of coarse aggregate, comprising: S1, weigh the mass of the coarse aggregate to be tested at the test temperature m 1; S2, mixing the coarse aggregate to be tested with asphalt to obtain an asphalt mixture; S3, weigh the mass of asphalt mixture at the test temperature m 2; S4, adding the asphalt mixture and the detection medium into the detection chamber, and performing ultrasonic detection on the asphalt mixture in the detection chamber to obtain the asphalt film thickness on the surface of the coarse aggregate in the asphalt mixture h ; S5, calculate the specific surface area s of coarse aggregate according to the following formula:
[0012] Where, s is the specific surface area of coarse aggregate; m 2 is the mass of asphalt mixture at the test temperature; m 1 is the mass of coarse aggregate at the test temperature; is the density of asphalt at the test temperature; h It is the thickness of asphalt film on the surface of coarse aggregate in asphalt mixture.
[0013] Preferably, in S4, the detection chamber is divided into multiple detection areas, and ultrasonic detection is performed on the asphalt mixture in each detection area to obtain the asphalt film thickness of each detection area, and the average value of the asphalt film thickness of each detection area is calculated, and the obtained average value is used as the asphalt film thickness on the surface of coarse aggregate in the asphalt mixture.
[0014] Preferably, in S4, after adding the asphalt mixture into the detection medium and before performing ultrasonic detection on the asphalt mixture in the detection chamber, the following step is also included: vacuuming the detection chamber.
[0015] Compared with the prior art, the present invention has the following beneficial effects: The coarse aggregate specific surface area testing device of the present invention comprises an ultrasonic detector, a testing chamber, a temperature control box, an electronic scale and an asphalt mixer; the coarse aggregate and asphalt are mixed by the asphalt mixer, the mass of the coarse aggregate and the asphalt mixture is weighed by the electronic scale, and the temperature of the testing chamber is controlled by the temperature control box at the testing temperature; the ultrasonic detector is used to detect the thickness of the asphalt film on the surface of the coarse aggregate in the asphalt mixture in the testing chamber at the testing temperature, so that the specific surface area of the coarse aggregate at the testing temperature can be calculated according to the thickness of the asphalt film, the mass of the coarse aggregate, the mass of the asphalt mixture and the density of the asphalt. The present invention uses ultrasonic waves to measure the specific surface area of the coarse aggregate, with high accuracy, low cost, good economy, and small equipment size, which is convenient for detection at any time.
[0016] Furthermore, the detection chamber of the present invention is shaped like a sphere, and the detection chamber is driven to rotate in the horizontal direction by a driving device. An ultrasonic detector can be used to detect the thickness of the asphalt film in different areas of the detection chamber, and then the average value is calculated. The average value is used to calculate the specific surface area of the coarse aggregate, thereby improving the accuracy of the detection result.
[0017] Furthermore, a bearing is installed at the intersection of the detection chamber and the base, which can reduce the resistance when the detection chamber rotates, so that the detection chamber can rotate better.
[0018] Furthermore, the present invention is provided with a vacuum pump, and when in use, the vacuum pump is used to eliminate bubbles in the material in the detection chamber, thereby improving the accuracy of the detection result.
[0019] The method for testing the specific surface area of highway coarse aggregate of the present invention obtains the thickness of asphalt film, the mass of coarse aggregate, the mass of asphalt mixture and the density of asphalt, and calculates the specific surface area of coarse aggregate at the test temperature based on these data. The present invention uses ultrasonic wave to measure the specific surface area of coarse aggregate, has high precision, low cost, good economy, and small equipment size, which is convenient for detection at any time. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0021] Figure 1 It is a structural schematic diagram of the coarse aggregate specific surface area testing device of the present invention; Figure 2 It is a stereoscopic diagram of the ultrasonic detector of the present invention; Figure 3 It is a side view of the ultrasonic detector of the present invention; Figure 4 It is a schematic diagram of the driving device of the present invention; Figure 5 It is a schematic diagram of the detection chamber of the present invention; Figure 6 It is a schematic diagram of the detection area division of the present invention; Figure 7 It is a schematic diagram of the temperature control box of the present invention.
[0022] Wherein: ultrasonic detection component 1, vacuum pump 2, medium collection bucket 3, asphalt mixer 4, electronic scale 5, base 6, temperature control box 7, ultrasonic detector fixing frame 11, detection chamber 12, detection chamber fixer 13, ultrasonic detector 14, bearing 15, second displacement plate 16, rack 17, rack sliding groove 18, second motor 19, gear 110, first displacement plate 111, screw 112, first motor 113, fixing bracket 114, detection chamber upper cover 121, detection chamber vacuum tube interface 122, agitator fixing bracket 41, agitator riser 42, third motor 43, transmission shaft 44, agitator 45, agitator cover 46, first gear 47, second gear 48, mixing barrel 49. DETAILED DESCRIPTION
[0023] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.
[0024] It should be noted that the process equipment or devices not specifically specified in the following embodiments are all conventional equipment or devices in the art.
[0025] It should be noted that the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to define the scope of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the present invention without substantially changing the technical content.
[0026] In addition, it should be noted that the terms "first", "second", etc. of the present invention are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. The orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention; in addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements.
[0027] refer to Figure 1 , Figure 2 and Figure 7 The coarse aggregate specific surface area testing device of the present invention comprises: an ultrasonic detection component 1, an electronic scale 5 and an asphalt mixer 4; the ultrasonic detection component 1 comprises an ultrasonic detector 14, a detection chamber 12 and a temperature control box 7; the asphalt mixer 4 is used to mix the coarse aggregate with asphalt to obtain an asphalt mixture; the detection chamber 12 is used to contain the asphalt mixture; the ultrasonic detector 14 is arranged on one side of the detection chamber 12, and is used to detect the thickness of the asphalt film on the surface of the coarse aggregate in the asphalt mixture in the detection chamber 12, and the temperature control box 7 is used to control the temperature in the detection chamber 12 at the test temperature; the electronic scale 5 is used to weigh the mass of the coarse aggregate and the asphalt mixture at the test temperature.
[0028] The specific surface area of coarse aggregate can be calculated based on the thickness of the asphalt film, the mass of coarse aggregate, the mass of asphalt mixture and the density of asphalt.
[0029] The specific calculation formula is:
[0030] Where, s is the specific surface area of coarse aggregate; m 2 is the mass of asphalt mixture at the test temperature; m 1 is the mass of coarse aggregate at the test temperature; is the density of asphalt at the test temperature; h It is the thickness of asphalt film in asphalt mixture.
[0031] In order to obtain a more accurate thickness of the asphalt film, in a specific embodiment of the present invention, the shape of the detection chamber 12 is set to be a sphere, and a driving device is provided, and the driving device is used to drive the detection chamber 12 to rotate. During detection, the detection chamber 12 can be divided into several detection areas. By rotating the detection chamber 12, the thickness of the asphalt film in different detection areas in the detection chamber 12 can be detected. According to the thickness of the asphalt film in different detection areas, the average thickness of the asphalt film is calculated, and the specific surface area of the coarse aggregate is calculated using the average thickness. The division of the detection area is as follows: Figure 6 shown.
[0032] In a specific embodiment of the present invention, the coarse aggregate specific surface area testing device is provided with ultrasonic detector fixing frames 11 installed on both sides of the detection chamber 12, and the ultrasonic detector 14 is arranged on a side of the ultrasonic detector fixing frame 11 close to the detection chamber 12, such as Figure 2 shown.
[0033] In order to further improve the accuracy of the test results, in a specific embodiment of the present invention, the coarse aggregate specific surface area test device further includes a vacuum pump 2, a medium collection bucket 3 ( Figure 1 ). When in use, asphalt mixture and detection medium are added to the detection chamber 12, the top of the detection chamber 12 is connected to the medium collection barrel 3 through a vacuum tube, and the medium collection barrel 3 is connected to the vacuum pump 2 through a vacuum tube. The vacuum pump 2 is used to evacuate the bubbles in the detection medium in the detection chamber 12, thereby avoiding the influence of bubbles and improving the accuracy of asphalt film thickness detection. Materials such as epoxy resin can be used as the detection medium. After the bubbles are eliminated, the connection between the medium collection barrel 3 and the detection chamber 12 is disconnected.
[0034] See also Figure 1 and Figure 4 In a specific embodiment of the present invention, the coarse aggregate specific surface area testing device further includes a base 6, and the vacuum pump 2 and the medium collection bucket 3 are both arranged on the base 6. The bottom of the detection chamber 12 passes through the base 6 and is connected to the driving device. A bearing 15 is installed at the intersection of the detection chamber 12 and the base 6, so that the detection chamber can rotate better.
[0035] See also Figure 3 and Figure 4In a specific embodiment of the present invention, the driving device is composed of a two-stage displacement structure. The first displacement structure includes a fixed bracket 114 and a first motor 113 and a lead screw module arranged on the fixed bracket 114. The output end of the first motor 113 is connected to one end of a lead screw 112 of the lead screw module. The lead screw 112 is threaded with a first displacement plate 111. The second displacement structure includes a second motor 19, a gear 110, a rack 17, and a rack sliding groove 18. The second motor 19 and the rack sliding groove 18 are arranged on the first displacement plate 111. The gear 110 is located above the second motor 19 and is coaxially connected to the output shaft of the second motor 19. The rack 17 is slidably installed in the rack sliding groove 18. The gear 110 is meshed with the rack 17, and the length direction of the rack 17 is perpendicular to the length direction of the lead screw. The top of the rack 17 is fixedly connected with a second displacement plate 16. The second displacement plate 16 is placed horizontally, and the bottom of the detection chamber 12 contacts the upper surface of the second displacement plate 16. The first displacement plate 111 is driven to move in the x direction by the lead screw module, thereby driving the second displacement plate 16 to move in the x direction. The gear 110 is driven to rotate by the second motor 19, and the gear 110 drives the rack 17 to move in the y direction, thereby driving the second displacement plate 16 to move in the y direction. Thus, the second displacement plate 16 can move in the horizontal direction, thereby driving the detection chamber 12 to rotate.
[0036] See also Figure 2 and Figure 4 In a specific embodiment of the present invention, a detachable detection chamber fixture 13 is installed on the upper part of the detection chamber 12.
[0037] See also Figure 5 A detection chamber upper cover 121 is provided on the top of the detection chamber 12, and a detection chamber vacuum tube interface 122 is provided on the detection chamber upper cover 121. When in use, the detection chamber vacuum tube interface 122 is connected to the medium collection barrel 3 through a vacuum tube.
[0038] like Figure 7 As shown, the temperature control box 7 of the present invention is a box-type structure, and the detection chamber 12, the detection chamber fixture 13, the ultrasonic detector 14, and the ultrasonic detector fixing frame 11 are all arranged in the temperature control box 7. A heater and a thermometer are arranged inside the temperature control box 7, which can control the temperature in the detection chamber 12 to the detection temperature.
[0039] like Figure 1As shown, in a specific embodiment of the present invention, the asphalt mixer 4 includes a mixing barrel 49 and an agitator fixing bracket 41; the mixing barrel and the agitator fixing bracket 41 can be fixed on the base 6. The agitator fixing bracket 41 includes a column and a crossbeam, and a stirrer riser 42 is installed in the middle of the column to make the stirrer rise or fall. A third motor 43 and a transmission shaft 44 are installed on the crossbeam. The output shaft end of the third motor 43 is connected to a first gear 47, and the upper end of the rotating shaft 44 is connected to a second gear 48, and the first gear 47 is meshed with the second gear 48, so that the transmission shaft 44 is driven to rotate by the third motor 43. A mixer cover 46 is installed at the lower end of the transmission shaft 44, and an agitator 45 is installed at the lower part of the mixer cover 46. The third motor 43 drives the transmission shaft 44 to rotate, driving the agitator 45 to rotate. An electric heating device is installed inside the mixing barrel to heat the asphalt and control the temperature. During mixing, the coarse aggregate to be tested is added to the asphalt and mixed. By controlling the quality of asphalt, the thickness of the asphalt film on the surface of the coarse aggregate particles is kept within a certain range, simulating the asphalt mixture production scene and improving the detection accuracy.
[0040] The specific surface area testing method of coarse aggregate of the present invention comprises the following steps: Weigh the mass of the coarse aggregate to be tested at the test temperature m 1. Put the coarse aggregate and asphalt to be tested into the asphalt mixer 4 and mix them. By controlling the asphalt quality, the thickness of the asphalt film on the surface of the coarse aggregate particles is kept within a certain range to simulate the asphalt mixture production scene. After cooling to the test temperature, weigh the mass of the asphalt mixture. m 2. After injecting a small amount of detection medium into the detection chamber 12, put the asphalt mixture in, and then add the detection medium to completely cover the asphalt mixture. Connect the medium collection barrel 3 to the detection chamber 12, start the vacuum pump 2, eliminate the bubbles in the detection medium, and then disconnect the medium collection barrel 3 from the detection chamber 12. Finally, start the ultrasonic detector 14 and the first motor 18, use the displacement plate 16 to control the rotation of the detection chamber 12, and perform ultrasonic detection on each detection area one by one at the test temperature to obtain the asphalt film thickness of each detection area. Then calculate the average asphalt film thickness, and then obtain the specific surface area of the coarse aggregate according to the following formula.
[0041] The specific calculation formula is:
[0042] Where, s is the specific surface area of coarse aggregate; m 2 is the mass of asphalt mixture at the test temperature; m 1 is the mass of coarse aggregate at the test temperature; is the density of asphalt at the test temperature; h It is the thickness of asphalt film in asphalt mixture.
[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.
Claims
1. A coarse aggregate specific surface area testing device, characterized in that: include: An ultrasonic detector (14), a detection chamber (12), a temperature control box (7), an electronic scale (5) and an asphalt mixer (4); the asphalt mixer (4) is used to mix coarse aggregate with asphalt to obtain an asphalt mixture; the detection chamber (12) is used to contain the asphalt mixture; the ultrasonic detector (14) is arranged on one side of the detection chamber (12) and is used to detect the thickness of the asphalt film on the surface of the coarse aggregate in the asphalt mixture in the detection chamber (12); the temperature control box (7) is used to control the temperature in the detection chamber (12) at a test temperature; and the electronic scale (5) is used to weigh the mass of the coarse aggregate and the asphalt mixture at the test temperature.
2. The coarse aggregate specific surface area testing device according to claim 1, characterized in that: The detection chamber (12) is in the shape of a sphere, and the coarse aggregate specific surface area testing device comprises a driving device, and the driving device is used to drive the detection chamber (12) to rotate.
3. The coarse aggregate specific surface area testing device according to claim 2, characterized in that: The coarse aggregate specific surface area testing device comprises a base (6), the bottom of the detection chamber (12) passes through the base (6) and is connected to a driving device; a bearing (15) is installed at the intersection of the detection chamber (12) and the base (6).
4. The coarse aggregate specific surface area testing device according to claim 2, characterized in that: The driving device comprises a first motor (113), a lead screw module, a second motor (19), a gear (110), a rack (17) and a rack sliding groove (18); the output end of the first motor (113) is connected to one end of a lead screw (112) of the lead screw module; the lead screw (112) is threadedly connected to a first displacement plate (111); the second motor (19) and the rack sliding groove (18) are arranged on the first displacement plate (111); the gear (110) is located above the second motor (19) and is coaxially connected to the output shaft of the second motor (19); the rack (17) is slidably mounted in the rack sliding groove (18); the gear (110) is meshedly connected to the rack (17); the length direction of the rack (17) is perpendicular to the length direction of the lead screw; the top of the rack (17) is fixedly connected to a second displacement plate (16); the second displacement plate (16) is placed horizontally; the bottom of the detection chamber (12) contacts the upper surface of the second displacement plate (16).
5. The coarse aggregate specific surface area testing device according to claim 1, characterized in that: The coarse aggregate specific surface area testing device comprises a vacuum pump (2) and a medium collecting bucket (3); when in use, the top of the detection chamber (12) is connected to the medium collecting bucket (3) via a vacuum tube, and the medium collecting bucket (3) is connected to the vacuum pump (2) via a vacuum tube.
6. The coarse aggregate specific surface area testing device according to claim 1, characterized in that: The coarse aggregate specific surface area testing device comprises an ultrasonic detector fixing frame (11), and the ultrasonic detector (14) is fixed on the ultrasonic detector fixing frame (11).
7. The coarse aggregate specific surface area testing device according to claim 1, characterized in that: The temperature control box (7) is a box-type structure, and the detection chamber (12) and the ultrasonic detector (14) are arranged in the temperature control box (7).
8. A method for testing the specific surface area of coarse aggregate, characterized in that: include: S1, weigh the mass of the coarse aggregate to be tested at the test temperature m 1; S2, mixing the coarse aggregate to be tested with asphalt to obtain an asphalt mixture; S3, weigh the mass of asphalt mixture at the test temperature m 2; S4, adding the asphalt mixture and the detection medium into the detection chamber, and performing ultrasonic detection on the asphalt mixture in the detection chamber to obtain the asphalt film thickness on the surface of the coarse aggregate in the asphalt mixture h ; S5, calculate the specific surface area s of coarse aggregate according to the following formula: Where, s is the specific surface area of coarse aggregate; m 2 is the mass of asphalt mixture at the test temperature; m 1 is the mass of coarse aggregate at the test temperature; is the density of asphalt at the test temperature; h It is the thickness of asphalt film on the surface of coarse aggregate in asphalt mixture.
9. The method for testing the specific surface area of coarse aggregate according to claim 8, characterized in that: In S4, the detection chamber is divided into multiple detection areas, and ultrasonic detection is performed on the asphalt mixture in each detection area to obtain the asphalt film thickness of each detection area, and the average value of the asphalt film thickness of each detection area is calculated, and the obtained average value is used as the asphalt film thickness on the surface of coarse aggregate in the asphalt mixture.
10. The method for testing the specific surface area of coarse aggregate according to claim 8, characterized in that: In S4, after the asphalt mixture is added into the detection medium and before the asphalt mixture in the detection chamber is ultrasonically detected, the following steps are also included: vacuuming the detection chamber.