Device and method for testing adhesive force between rock base material and asphalt

Abstract

The invention relates to an asphalt mixture, and discloses a rock base material and asphalt adhesive force testing device and method. The device comprises computing equipment, a controller and a drawing instrument, the drawing instrument comprises a bottom plate, a drawing base, a stand column, an upper cross beam, a sensor, a bonding strength upper drawing head and an electronic cylinder; wherein the electronic cylinder is connected with the sensor, the electronic cylinder is used for driving the sensor to move in the vertical direction and driving the bonding strength upper drawing head to move in the vertical direction, and the controller is electrically connected with the sensor and the electronic cylinder and used for receiving measurement data of the sensor and controlling movement of the electronic cylinder; and the computing equipment is used for communicating with the drawing instrument and the controller, setting test parameters, monitoring the running state of the drawing instrument and recording and analyzing data. According to the embodiment of the invention, the rock base material and asphalt adhesive force pull-out test can be scientifically, simply and conveniently carried out.

Description

TECHNICAL FIELD

[0001] The embodiments of the present application relate to asphalt mixture, in particular to a rock matrix and asphalt adhesion test device and method. BACKGROUND

[0002] High-grade highway asphalt pavement usually uses machine-made sand as fine aggregate, and the machine-made sand has a great influence on the road performance of asphalt mixture, especially the adhesion with asphalt which has a great influence on the water stability of asphalt mixture. The rock matrix is the raw material for preparing machine-made sand, and the prior art lacks a testing device and method for the adhesion between the rock matrix and asphalt mixture, so as to guarantee the water stability and other technical performances of machine-made sand asphalt mixture. How to provide a scientific and simple test method and device for the adhesion between fine aggregate and asphalt is a problem to be solved at present. SUMMARY

[0003] In view of the above problems, the embodiments of the present application provide a rock matrix and asphalt adhesion test device and method, which can scientifically and simply perform the rock matrix and asphalt adhesion pull-out test.

[0004] According to an aspect of the embodiments of the present application, a rock matrix and asphalt adhesion test device is provided, comprising a computing device, a controller and a pull-out tester; The pull-out tester comprises: a bottom plate, on which a pull-out base is fixed through a detachable base; a stand column erected on the bottom plate; an upper cross beam fixed to the top end of the stand column; a sensor fixed to the bottom of the upper cross beam; a bonding strength pull-out head connected with the sensor through a universal joint; an electronic cylinder fixed to the top of the upper cross beam; The electronic cylinder is connected with the sensor, and the electronic cylinder is used to drive the sensor to move vertically and drive the bonding strength pull-out head to move vertically. The controller is electrically connected with the sensor and the electronic cylinder, and is used to receive the measurement data of the sensor and control the movement of the electronic cylinder. The computing device is used to communicate with the pull-out tester and the controller, set test parameters, monitor the running state of the pull-out tester, and record and analyze data.

[0005] Optionally, the bottom of the upper cross beam is fixed with a sensor seat, and the sensor is fixed to the bottom of the upper cross beam through the sensor seat.

[0006] Optionally, the sensor is a tension sensor, the tension sensor has a range greater than or equal to 3000N, an accuracy greater than or equal to 1N, and a value error of force less than or equal to 1%.

[0007] Optionally, the sensor is provided with a universal joint adapter at the bottom, the universal joint adapter is fixed with the universal joint at the bottom, and the universal joint is used to connect the electronic cylinder and the bonding strength pull head to transmit the power of the electronic cylinder while allowing the bonding strength pull head to rotate freely within a certain angle range.

[0008] Optionally, the universal joint is provided with a connecting head at the bottom, and the bonding strength pull head is connected with the universal joint through the connecting head.

[0009] According to another aspect of the embodiment of the present application, a rock matrix and asphalt adhesion test method is provided, which uses a marketed rock matrix and asphalt adhesion test device to perform the test, and the method comprises the following steps: Step one: a core drill is used to drill a rock core sample on the rock matrix, and a cutting machine is used to cut the rock core sample into a small cylinder with flat ends to obtain a cylindrical test sample ; Step two: a first sandpaper is used to coarsely grind one end of the cylindrical test sample, and a second sandpaper is used to finely grind it, and the ground core sample is dried to a constant weight, wherein the mesh number of the first sandpaper is less than that of the second sandpaper; Step three: the bottom surface of the dried core sample is adhered to the pull base, wherein the pull base has not been assembled to the bottom plate; Step four: the asphalt test sample is heated, and the bonding strength pull head is preheated at the same heating temperature as the asphalt; Step five: after the asphalt is completely melted, an asphalt is taken with a glass rod, dropped on the top surface of the ground and flattened core sample, and then the bonding strength pull head is taken out and pressed on the surface of the asphalt, and pressed for 5-10 minutes. The bonding strength pull head does not slide during the entire pressing process. The test piece is placed at room temperature, and the asphalt is cooled and solidified after the asphalt is cooled and solidified to complete the test piece forming, wherein the test piece comprises the pull base, the core sample, the asphalt, and the bonding strength pull head; Step six: the test piece is placed in a 25±2℃ constant temperature box for 2-3h, and the test piece after curing is installed between the sensor and the bottom plate; Step seven: the test piece is subjected to vertical tension by the electronic cylinder, and when the pressure measured by the sensor reaches a peak value and no longer increases, the pressurization is stopped, and the peak force is read; wherein the pressure measured by the sensor is transmitted to the computing device for display through the controller; Step eight: the test sample pulling strength is calculated. the tensile strength of the sample, the tensile strength of the sample, the peak load at the time of failure of the sample, the peak load at the time of failure of the sample, the area of the asphalt film.

[0010] Optionally, the asphalt sample in step four is base asphalt or modified asphalt, wherein the heating temperature of the base asphalt is 140-160 DEG C, and the heating temperature of the modified asphalt is 170-180 DEG C.

[0011] Optionally, the rock matrix in step one is a matrix with good structural integrity, and when drilling the core, the micro cracks near the rock surface are avoided, and when cutting and segmenting the drilled core sample, the top surface and the bottom surface of the core sample are ensured to be parallel.

[0012] Optionally, in step three, the epoxy resin or AB glue is used to stick the dried core sample bottom surface to the pulling base.

[0013] Optionally, in step one, the diameter of the core drilling machine is 25±1mm, and the height of the small cylinder after cutting is 25mm±1mm; in step two, the polished core sample is placed in an oven at 160 DEG C and dried to constant weight.

[0014] The rock matrix and asphalt adhesion test device provided by the embodiment of the application is provided with a bottom plate, a pulling base is fixed on the bottom plate through a detachable base, an upper cross beam is fixed to the bottom plate through a stand column, a sensor is fixed to the bottom of the upper cross beam, a bonding strength pulling head is fixed below the sensor, an electronic cylinder is fixed to the top of the upper cross beam and connected with the sensor, the electronic cylinder drives the bonding strength pulling head to move relative to the pulling base, so as to test the adhesion of the rock matrix and the asphalt, and the pulling strength is calculated according to the measured adhesion. The rock matrix and asphalt adhesion pulling test method provided by the embodiment of the application is scientific and simple, can effectively meet the use requirements of the machine-made sand asphalt mixture, prolong the service life of the highway engineering, and effectively avoid diseases such as loose, pit and crack of the asphalt pavement.

[0015] The above description is only a summary of the technical scheme of the application, in order to more clearly understand the technical means of the application, the specific embodiments of the application can be implemented according to the content of the specification, and in order to make the above and other purposes, characteristics and advantages of the application more obvious and easy to understand, the following specific embodiments of the application are described. BRIEF DESCRIPTION OF DRAWINGS

[0016] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments and are not meant to limit the scope of the application. Moreover, the same reference numerals in different figures represent the same or similar components. In the drawings: Figure 1 The structural block diagram of the rock matrix and asphalt adhesion test device provided by the embodiment of the application is shown in the figure; Figure 2 The structural schematic diagram of the pull-out tester provided by the embodiment of the application is shown in the figure; Figure 3 The sectional view of the pull-out head for bond strength provided by the embodiment of the application is shown in the figure; Figure 4 The bottom view of the pull-out head for bond strength provided by the embodiment of the application is shown in the figure.

[0017] The reference signs in the detailed description are as follows: 1. A computing device; 2. A controller; 3. A pull-out tester; 31. A base plate; 32. A leveling foot; 33. A pull-out base; 34. A detachable base; 35. A pull-out head for bond strength; 36. A stand column; 37. An upper cross beam; 38. A sensor seat; 39. A sensor; 40. A universal joint adapter; 41. A universal joint; 42. A connecting head; 421. A threaded connecting head; 422. A penetrating pin; 43. An electronic cylinder. DETAILED DESCRIPTION

[0018] The embodiments of the technical solutions of the application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the application, and therefore only serve as examples, and cannot limit the protection scope of the application.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the application; the terms “include” and “have” and any variations thereof in the specification and claims of the application and the above description of drawings are intended to cover non-exclusive inclusion.

[0020] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise explicitly specified and limited.

[0021] Reference herein to "embodiments" means that the particular features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily a separate or alternative embodiment to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating any combination of the listed objects. For example, "A and / or B" can mean that A exists, A and B exist at the same time, or B exists. In addition, the character " / " herein generally indicates that the front and rear associated objects are in an "or" relationship.

[0023] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0024] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0025] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0026] Machine-made sand is rock particles with particle size less than 4.75 mm made by mechanical crushing, screening and other processes, which has regular particle shape, adjustable gradation, low clay content, and is usually used as fine aggregate in high-grade highway asphalt pavement. The surface of machine-made sand is rough and has large specific surface area, which not only provides more adhesion points for asphalt, but also forms stable chemical bonds through chemical reaction between mineral components and organic substances in asphalt, significantly enhancing the adhesion between asphalt and aggregate. The improvement of adhesion has a significant impact on the road performance of asphalt mixture, especially the water stability, effectively improving the water damage resistance of asphalt mixture, reducing asphalt film peeling, aggregate loosening and pavement potholes caused by water erosion, and thus ensuring the long-term stability and durability of the pavement.

[0027] The technical index system of machine-made sand in existing standards is not perfect. The adhesion standard of coarse aggregate and asphalt in asphalt mixture is specified in the Technical Specification for Construction of Highway Asphalt Pavement JTG F40-2004, but the adhesion standard of fine aggregate or machine-made sand and asphalt in asphalt mixture is not specified, and the test method of adhesion of fine aggregate and asphalt is not specified in the Test Rules for Highway Engineering Asphalt and Asphalt Mixture JTG E20-2011. The rock matrix is the raw material for preparing machine-made sand, and the existing technology lacks the test of adhesion between rock matrix and asphalt mixture, so as to ensure the water stability and other technical properties of machine-made sand asphalt mixture.

[0028] Therefore, how to test and evaluate the adhesion between rock matrix and asphalt is a problem to be solved.

[0029] The present application provides a rock matrix and asphalt adhesion test device and test method, which can scientifically and simply detect the adhesion between rock matrix and asphalt. The present application evaluates the adhesion between rock matrix and asphalt by pull-out test. The principle of pull-out test is the friction between rock matrix and asphalt. By applying normal stress, the maximum static friction force resisting external force on the interface between rock matrix and asphalt is obtained, and the pull-out strength at 25℃ (curing temperature of test piece) is used as an index to evaluate the adhesion between rock matrix and asphalt.

[0030] The embodiments of the present application will be described in detail below.

[0031] Figure 1 The structural block diagram of the rock matrix and asphalt adhesion test device provided by the embodiments of the present application is shown in Figure 1As shown, the test device includes a computing device 1, a controller 2 and a puller 3. The computing device 1 is electrically connected with the controller 2 and the puller 3 respectively, and the controller 2 is also electrically connected with the puller 3. Among them, the computing device 1 can be a smart phone, a tablet computer, a notebook computer, a desktop computer, an all-in-one machine and other electronic devices that can install test software. The controller 2 is used to receive the feedback signal of the puller 3, and control the movement of the puller 3 according to the preset program, to ensure the accurate control of the pulling process. The computing device 1 is used to communicate with the puller 3 and the controller 2, set the test parameters, monitor the running state of the puller 3, and record and analyze the data. The computing device 1 can include a display unit for setting test parameters and displaying test results.

[0032] Figure 2 The structural schematic diagram of the puller 3 provided by the embodiment of the present application is shown as follows, Figure 2 As shown, the puller 3 includes a base plate 31, which is the basic component of the puller 3 and is used to support the entire device to ensure that the puller 3 remains stable during the test process. The base plate 31 can be placed on the ground or a mounting plane such as a table top through leveling feet 32. As shown in the figure, one leveling foot 32 is arranged on each side of the base plate 31. The leveling feet 32 are adjusted according to the mounting plane on which the puller 3 is placed, to adjust the horizontal position of the puller 3 and ensure that the puller 3 remains stable during the test process, avoiding the influence of the test results due to the inclination of the puller 3.

[0033] The base plate 31 is fixed with a pulling base 33, and the pulling base 33 is fixed to the base plate 31 through a detachable base 34. The detachable base 34 can be fixed to the base plate 31 by welding or threaded connection and the like. Preferably, the detachable base 34 is fixed to the middle part of the base plate 31, so that the pulling base 33 is also located in the middle part of the base plate 31. The pulling base 33 is used to fix the rock matrix, to ensure that the rock matrix remains stable during the pulling process and does not move or incline.

[0034] Opposite to the pulling base 33, the puller 3 also includes a bonding strength upper pulling head 35 for carrying out the bonding strength test, Figure 3 The cross-sectional view of the bonding strength upper pulling head provided by the embodiment of the present application is shown as follows, Figure 4 The bonding strength upper pulling head provided by the embodiment of the present application is shown as follows. The bonding strength upper pulling head 35 is arranged at a vertically upward position of the pulling base 33 and can move up and down along the vertical direction relative to the pulling base 33. The bonding strength upper pulling head 35 is used to directly contact and pull the rock matrix and asphalt sample to test the adhesion of the rock matrix and asphalt.

[0035] Two upright columns 36 are arranged on both sides of the base plate 31, which are the support structures of the pull-out tester 3, used to connect the base plate 31 and the upper cross beam 37, to ensure the overall height and stability of the device. The top end of the upright column 36 is fixed with the upper cross beam 37, which can be fixed to the upright column 36 through threaded fasteners. The upper cross beam 37 is the upper support structure of the pull-out tester 3, used to connect and fix other components, to ensure the overall stability and rigidity of the pull-out tester 3 during the pulling process.

[0036] The bottom of the upper cross beam 37 is fixed with a sensor seat 38, which is used to install and fix the sensor 39. The sensor 39 is used to monitor the force value in real time during the pulling process, and feed back these data to the controller 2, to realize the accurate control of the pulling force. Through the sensor seat 38, it can ensure that the sensor 39 can accurately detect and feedback the force value change during the pulling process. As shown in the figure, the sensor 39 is fixed at the bottom of the sensor seat 38.

[0037] The sensor 39 can be a tension sensor, which is used to detect the pulling force received by the bonding strength upper pulling head 35, and transmit the detected pulling force data to the controller 2. The tension sensor has a range greater than or equal to 3000N, that is, the maximum force value that can be measured by the tension sensor is at least 3000N, the accuracy is greater than or equal to 1N, and the indicated error of the force value is less than or equal to 1%.

[0038] The bottom of the sensor 39 is provided with a universal joint adapter 40, and the bottom of the universal joint adapter 40 is fixed with a universal joint 41. The universal joint 41 is used to connect the electronic cylinder 43 and the bonding strength upper pulling head 35, to transmit the power of the electronic cylinder 43, while allowing the bonding strength upper pulling head 35 to rotate freely within a certain angle range, including horizontal, vertical and inclined directions. Within a certain range, the angle of the bonding strength upper pulling head 35 can be adjusted to adapt to rock matrix and asphalt samples of different shapes and sizes, to ensure uniform distribution of pulling force. Specifically, a first threaded column is arranged below the sensor 39, and a first threaded hole is arranged above the universal joint adapter 40, which are matched to connect the sensor 39 and the universal joint adapter 40.

[0039] If a one-way rotating connecting component is used to replace the universal joint 41, it will result in the limited angle adjustment ability of the pull head 35 on the bonding strength, which cannot adapt to complex sample shapes, reduces the reliability of the test, and increases the operation complexity. Specifically, the universal joint 41 allows the pull head 35 on the bonding strength to rotate freely within a certain angle range, so as to adapt to rock matrix and asphalt samples of different shapes and sizes, and ensure uniform distribution of pulling force; while the one-way rotating component cannot provide such multi-directional angle adjustment ability, which may cause the pull head 35 on the bonding strength to be unable to accurately align with the optimal stress position and angle of the sample, thereby affecting the accuracy of the test results. In actual application, the contact surface shape and size of the rock matrix and asphalt sample may be irregular, and the pull head 35 on the bonding strength needs to be flexibly adjusted in multiple directions. The multi-directional rotating feature of the universal joint 41 can well meet this demand, while the one-way rotating component cannot adapt to such complexity, which may cause insufficient contact or uneven stress between the pull head 35 on the bonding strength and the sample. Due to the inability to flexibly adjust the angle in multiple directions, the one-way rotating component will limit the applicability and flexibility of the pull head 35 on the bonding strength, thereby reducing the reliability and effectiveness of the entire pull tester, and failing to guarantee the stability and accuracy under various test conditions. The universal joint 41 allows the angle of the pull head 35 on the bonding strength to be freely adjusted within a certain range, and the use of the universal joint 41 can simplify the operation process without the need to frequently disassemble and reinstall components; while the one-way rotating component may require the operator to spend more time and effort to adjust the position and angle of the pull head, increasing the complexity and workload of the operation.

[0040] The bottom of the universal joint 41 is connected with the pull head 35 on the bonding strength through a connecting head 42, so as to realize the connection of the pull head 35 on the bonding strength. The connecting head 42 is used to ensure the close fit and power transmission between the universal joint 41 and the pull head 35 on the bonding strength, and to ensure the stability during the test. The connecting head 42 includes a threaded connecting head 421 and a pin 422. The threaded connecting head 421 can be an M12 threaded connecting head, and the pin 422 can be a pin with a φ12 aperture. Specifically, a second threaded column is arranged below the connecting head 42, and a second threaded hole is arranged above the pull head 35 on the bonding strength, and the second threaded column and the second threaded hole are matched to connect the pull head 35 on the bonding strength and the connecting head 42.

[0041] The upper cross beam 37 is supported by the column 36, thereby providing space for the installation of components such as the sensor seat 38, the sensor 39, the universal joint adapter 40, the universal joint 41, the connecting head 42, and the pull head 35 on the bonding strength, and providing a pull test area. Moreover, the pull test area is supported by the upper cross beam 37, the column 36, and the bottom plate 31.

[0042] The top of the upper cross beam 37 is provided with an electronic cylinder 43, which can be a hole hydraulic cylinder. The electronic cylinder 43 is a driving component of the puller 3 and is responsible for providing accurate pulling force. The cylinder body or piston of the hole hydraulic cylinder is provided with a hole or channel for component movement.

[0043] The controller 2 is electrically connected with the sensor 39 to receive feedback signals of the sensor 39. The controller 2 is also electrically connected with the electronic cylinder 43 to control the movement of the electronic cylinder 43 according to a preset program, so as to control the electronic cylinder 43 to output accurate pulling speed and force, and ensure the accuracy and repeatability of the test. The controller 2 can be a PLC controller or an IAI electric cylinder controller.

[0044] The process of using the rock matrix and asphalt adhesion test device to test the rock matrix and asphalt adhesion will be described below.

[0045] The rock matrix and asphalt adhesion test method includes the following steps: Step one: A core drill with a diameter of 25±1mm is used to drill a rock core sample on the rock matrix, and a cutting machine is used to cut the rock core sample into a small cylinder with a height of 25mm±1mm and flat ends, to obtain a cylindrical test sample; In this step, the core sample with a fixed height of 25±1mm is obtained by fixing the diameter of the core drill to 25±1mm, so as to realize standardized sampling, ensure the uniformity of the test sample size, and reduce test errors caused by size differences. The cylindrical test sample with flat ends is obtained by cutting with a cutting machine, which ensures the flatness requirement and guarantees the uniformity of subsequent polishing and bonding, thereby avoiding uneven distribution of asphalt caused by uneven end faces.

[0046] Step two: 150-grit sandpaper is used to roughen one end of the cylindrical test sample, and the sandpaper is polished in a clockwise direction for 10 circles and in a counterclockwise direction for 10 circles, and the circle size is appropriate; then 320-grit sandpaper is used for fine grinding, and the grinding direction and number of circles should be consistent with the rough grinding. The polished core sample is placed in an oven at 160℃ and dried to constant weight, and then taken out for standby use; In this step, a hierarchical polishing process is adopted. First, 150-grit sandpaper is used to remove surface impurities and form a uniform roughness, and then 320-grit sandpaper is used for further surface refinement to increase the contact area and adhesion between asphalt and rock. Further, bidirectional polishing (10 circles clockwise and counterclockwise) is used to avoid directional deviation caused by unidirectional polishing, thereby ensuring the uniformity of the surface. Finally, the drying temperature is selected as 160℃, which can completely remove the water adsorbed on the surface of the rock, thereby preventing water residue from affecting the asphalt adhesion test results.

[0047] Step three: The bottom surface of the dried core sample is bonded to the pulling base 33 using epoxy resin or AB glue. If the core sample falls off during the test, the test result is not counted. In this step, the pulling base 33 has not been assembled to the base plate 31. This step selects high-strength adhesive such as epoxy resin or AB glue, which can withstand the test tension and avoid non-interface failure (such as bonding failure) interference data. And it adopts the mechanism of falling out, excludes invalid data caused by poor bonding, and improves the reliability of test results.

[0048] Step four: heat the asphalt sample, the heating temperature of the base asphalt is 140-160℃, and the heating temperature of the modified asphalt is 170-180℃; the bonding strength pull head 35 is preheated in the oven at the same heating temperature as the asphalt; This step adopts differential heating temperature, adjusts the temperature according to the type of asphalt (base / modified), ensures that the fluidity of asphalt is appropriate, and the softening point of base asphalt is low, the heating temperature is lower than that of modified asphalt, while the modified asphalt needs higher temperature. In order to avoid the large temperature difference between the pull head and the asphalt, which leads to the rapid cooling and shrinkage of the asphalt, affecting the interface contact quality, the pull head is also preheated.

[0049] Step five: after the asphalt is completely melted, 1-2 drops of asphalt are taken with a glass rod, dropped on the top surface of the polished core sample, and then the bonding strength pull head 35 is immediately taken out and pressed on the asphalt surface, with a force of 10±1N for 5-10min, and the bonding strength pull head 35 does not slide during the whole pressing process. The test piece is placed at room temperature for 1h, and after the asphalt cools and solidifies, the excess asphalt around the bonding strength pull head 35 is scraped off with a hot scraper, and the test piece is completed; The test piece includes pull base 33, core sample and asphalt, and bonding strength pull head 35; This step adopts quantitative drop of asphalt (1-2 drops), controls the amount of asphalt, ensures the consistency of asphalt film thickness and area (the area of asphalt film can be taken as a fixed value 3.14×10⁻ 4 m² in subsequent calculation). When pressing the bonding strength pull head 35, precise pressing method (10±1N, 5-10min) is adopted, which can make the asphalt and rock fully infiltrate through constant pressure and time, simulate the combination process of asphalt and aggregate in actual engineering. In addition, by scraping off the excess material, it avoids the interference of excess asphalt in the calculation of pull area, and ensures the test accuracy.

[0050] Step six: put the test piece into a 25±2℃ constant temperature box for 2-3h, and install the test piece between the sensor 39 and the detachable base 34 after curing; This step adopts constant temperature curing conditions, simulates the conventional environmental temperature in a 25±2℃ constant temperature box, so that the asphalt can be fully cured and reach a stable state, and the influence of temperature fluctuation on adhesion strength is reduced. The curing time is 2-3h, which can balance the test efficiency and the curing demand of asphalt, and avoid performance deviation caused by insufficient or excessive curing.

[0051] Step 7: Press the hydraulic cylinder with a hole to apply vertical tension to the specimen. When the pressure measured by sensor 39 reaches a peak value and no longer increases, it indicates that the interface between the core sample and the asphalt has been damaged. Stop pressurizing and read the peak force. The pressure measured by sensor 39 can be transmitted to a laptop computer for display via controller 2.

[0052] This step uses the sensor's peak pressure as the critical point of failure, objectively reflecting the maximum adhesion of the interface and avoiding human misjudgment. The controller is connected to a laptop computer for real-time data transmission and automatic recording, reducing manual reading and recording errors.

[0053] Step 8: Remove the test piece (including the pulling base 33, the core sample and the asphalt and the bonding strength pulling head 35), observe and record the failure mode of the interface, and label the core sample with the number, peak pulling force, etc.; This step assists in evaluating the adhesion between asphalt and rock by observing interface failure modes (e.g., cohesive failure, interfacial debonding, etc.). Labeling facilitates tracing the relationship between test data and specimens, improving the systematic and repeatable nature of data management.

[0054] Step 9: Carry out at least 6 parallel tests on the same sample (corresponding to the sample obtained in step 5). The pull-out strength is defined as the ratio of the peak load at which the interface is damaged to the asphalt film area. The tensile strength of each specimen is calculated according to formula (1).

[0055] (1) In the above formula: For the sample Pull-out strength (kPa), For the sample Peak load at failure (N), is the area of ​​the asphalt film. Here, the area of ​​the asphalt film is calculated based on the core drilling machine diameter of 25±1 mm, which is 3.14×10 -4 m 2 , A in formula (1) can be fixed to 3.14×10 -4 m 2 .

[0056] The average pull-out strength obtained from multiple parallel tests is used to obtain the The final test results.

[0057] This step requires ≥6 parallel tests to reduce accidental errors through multiple tests and ensure statistical significance of the data. The standardized calculation formula of formula (1) is used to uniformly define the pull-out strength as the ratio of peak load to fixed area, simplifying the calculation process and enhancing the comparability of the results.

[0058] The rock matrix and asphalt adhesion test method provided by the embodiments of the present application realizes high-precision and repeatable testing of the rock matrix and asphalt adhesion by strictly stipulating the sample size, polishing process, heating temperature, pressing parameters and data acquisition mode, so that the pullout strength can be calculated based on the measured adhesion. The parameter ranges of each step (such as temperature, pressure, and time) are optimized based on the material properties, taking into account the test efficiency and result reliability, and are suitable for asphalt mixture mix design and quality control in engineering practice.

[0059] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should be understood as the usual meaning understood by the skilled person in the field to which the embodiments of the present application belong.

[0060] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A rock base material and asphalt adhesion test device, characterized in that: including computing equipment, controller and drawing apparatus; The pulling apparatus comprises: a base plate on which the pull-out base is fixed via a detachable base; A column, mounted on the base plate; an upper crossbeam fixed to the top of the column; a sensor, fixed to the bottom of the upper beam; The bonding strength upper pulling head is connected to the sensor through a universal joint, and the bonding strength upper pulling head can rotate with the sensor in the horizontal direction, vertical direction and tilt direction through the universal joint; An electronic cylinder, fixed to the top of the upper beam; The electronic cylinder is connected to the sensor, and is used to drive the sensor to move vertically and drive the bonding strength upper pulling head to move vertically. The controller is electrically connected to the sensor and the electronic cylinder, respectively, and is used to receive measurement data from the sensor and control the movement of the electronic cylinder. The computing device is used to communicate with the pulling instrument and the controller, set test parameters, monitor the operating status of the pulling instrument, and record and analyze data. The process of using the device to conduct a rock base material and asphalt adhesion test includes the following steps: Step 1: Use a core drill to drill a rock core sample from the rock matrix, and use a cutter to cut the rock core sample into small cylinders with flat ends to obtain a cylindrical sample. ; Step 2: Use the first sandpaper to rub the cylindrical specimen coarsely grinding one end of the core sample with a second sandpaper, and then finely grinding with a second sandpaper, and drying the polished core sample to a constant weight, wherein the mesh number of the first sandpaper is smaller than the mesh number of the second sandpaper; Step 3: gluing the bottom surface of the dried core sample to the drawing base, wherein the drawing base has not yet been assembled to the bottom plate; Step 4: heating the asphalt sample, and preheating the bonding strength puller to the same heating temperature as the asphalt sample; Step 5: After the asphalt sample is completely melted, use a glass rod to dip asphalt and drip it onto the top surface of the polished core sample. Then, take out the bonding strength upper pulling head and press it on the asphalt surface for 5 to 10 minutes. The bonding strength upper pulling head does not slide during the entire pressing process. The specimen is left to stand at room temperature. After the asphalt cools and solidifies, the specimen is formed. The specimen includes the pulling base, the core sample, the asphalt, and the bonding strength upper pulling head. Step 6: Place the test piece in a constant temperature box at 25±2°C for 2-3 hours, and then install the test piece between the sensor and the base plate; Step 7: applying a vertical tensile force to the specimen via the electronic cylinder. When the pressure measured by the sensor reaches a peak value and no longer increases, stopping the pressurization and reading the peak force. The pressure measured by the sensor is transmitted to the computing device for display via the controller. Step 8: Calculate the sample Pull-out strength , For the sample The pull-out strength, For the sample The peak load at failure, is the area of ​​the asphalt film.

2. The device according to claim 1, characterized in that A sensor seat is fixed to the bottom of the upper crossbeam, and the sensor is fixed to the bottom of the upper crossbeam through the sensor seat.

3. The device according to claim 1, characterized in that The sensor is a tension sensor, the measuring range of which is greater than or equal to 3000N, the accuracy of which is greater than or equal to 1N, and the indication error of the force value of which is less than or equal to 1%.

4. The device according to claim 1, characterized in that A universal joint adapter is provided at the bottom of the sensor, and the universal joint is fixed at the bottom of the universal joint adapter. The universal joint is used to connect the electronic cylinder and the bonding strength upper pulling head to transmit the power of the electronic cylinder while allowing the bonding strength upper pulling head to rotate freely within a certain angle range.

5. The device according to claim 1, characterized in that A connecting head is provided at the bottom of the universal joint, and the bonding strength upper pulling head is connected to the universal joint through the connecting head.

6. A method for testing the adhesion between rock parent material and asphalt, characterized in that: The method uses the rock base material and asphalt adhesion test device according to any one of claims 1 to 5 to conduct the test, and the method comprises the following steps: Step 1: Use a core drill to drill a rock core sample from the rock matrix, and use a cutter to cut the rock core sample into small cylinders with flat ends to obtain a cylindrical sample. ; Step 2: Use the first sandpaper to rub the cylindrical specimen coarsely grinding one end of the core sample with a second sandpaper, and then finely grinding with a second sandpaper, and drying the polished core sample to a constant weight, wherein the mesh number of the first sandpaper is smaller than the mesh number of the second sandpaper; Step 3: gluing the bottom surface of the dried core sample to the drawing base, wherein the drawing base has not yet been assembled to the bottom plate; Step 4: heating the asphalt sample, and preheating the bonding strength puller to the same heating temperature as the asphalt sample; Step 5: After the asphalt sample is completely melted, use a glass rod to dip the asphalt and drip it onto the top surface of the polished core sample. Then, take out the bonding strength upper pulling head and press it on the asphalt surface for 5 to 10 minutes. The bonding strength upper pulling head does not slide during the entire pressing process. The specimen is left to stand at room temperature. After the asphalt cools and solidifies, the specimen is formed. The specimen includes the pulling base, the core sample, the asphalt, and the bonding strength upper pulling head. Step 6: Place the test piece in a constant temperature box at 25±2°C for 2-3 hours, and install the test piece between the sensor and the base plate after curing; Step 7: applying a vertical tensile force to the specimen via the electronic cylinder. When the pressure measured by the sensor reaches a peak value and no longer increases, stopping the pressurization and reading the peak force. The pressure measured by the sensor is transmitted to the computing device for display via the controller. Step 8: Calculate the sample Pull-out strength , For the sample The pull-out strength, For the sample The peak load at failure, is the area of ​​the asphalt film.

7. The method according to claim 6, characterized in that The asphalt sample in step 4 is base asphalt or modified asphalt, wherein the heating temperature of the base asphalt is 140-160°C, and the heating temperature of the modified asphalt is 170-180°C.

8. The method according to claim 6, characterized in that In the step 1, the rock matrix is ​​a matrix with good structural integrity. Microcracks near the rock surface are avoided during core drilling. When the drilled core sample is cut into sections, the top and bottom surfaces of the core sample are ensured to remain parallel.

9. The method according to claim 6, characterized in that In the step three, the bottom surface of the dried core sample is glued to the drawing base using epoxy resin or AB glue.

10. The method according to claim 6, characterized in that In the step 1, the diameter of the core drill is 25±1 mm, and the height of the small cylinder after cutting is 25 mm±1 mm; in the step 2, the polished core sample is placed in an oven at 160° C. and dried to constant weight.

Images