Quantitative detection method for optimal asphalt dosage of asphalt chip seal and rolling device

Abstract

The present invention discloses a quantitative detection method for the optimal asphalt dosage of asphalt chip seal, which relates to the field of road maintenance technology. Asphalt chip seals with different asphalt spreading amounts are formed in a sample template. A plurality of rutting plate test pieces are formed above the asphalt chip seals. Grooves are left between adjacent rutting plate test pieces, and a first volume V0 of the grooves is measured. A matching test block is placed in the grooves. The asphalt overflow effect in the asphalt chip seal is caused by line kneading to simulate on-site rolling, and the second volume V0 of the grooves is measured. i The optimal asphalt dosage for the asphalt chip seal is determined by measuring the rutting test results through a rutting test. When the dynamic stability DS curve shows an inflection point, the optimal asphalt dosage for the asphalt chip seal is determined. The present invention also provides an asphalt chip seal rolling device for implementing the above-mentioned testing method. This invention takes into account on-site rolling results and can quantitatively determine the optimal asphalt dosage for the asphalt chip seal, thereby extending the service life of the pavement.

Description

Technical Field

[0001] The present invention relates to the technical field of road maintenance, in particular to a quantitative detection method for an optimal asphalt dosage of an asphalt chip seal layer and a rolling device. Background Art

[0002] Asphalt chip seal is a common construction technique used in major and medium-sized pavement repairs. Asphalt and coarse aggregate are spread over the base layer or existing pavement by hand or with specialized vehicles. The layer is then compacted promptly by a roller and then allowed to pass through traffic, creating a thin, 1-3 cm thick layer. The main functions of an asphalt chip seal are to bond the base layer to the asphalt surface layer; prevent rainwater from seeping into the base layer, reducing its bearing capacity; and absorb vehicle impact loads.

[0003] my country spans multiple climate zones. The existing construction specifications for asphalt gravel seal coats specify a range of asphalt usage, but do not specify the optimal asphalt usage. This results in experience-based control being used in actual use, and due to weather conditions, asphalt spreading may exceed or be insufficient during actual asphalt gravel construction. After the subsequent asphalt surface layer is spread, the rutting resistance of the asphalt pavement drops sharply under heavy vehicle loads, resulting in rutting damage. Alternatively, precipitation may seep through cracks in the asphalt road surface to the base layer, reducing the bearing capacity of the base layer and causing road subsidence.

[0004] Therefore, it is necessary to develop a quantitative detection method for the optimal asphalt dosage of asphalt chip seal to determine the optimal asphalt dosage under different conditions and extend the service life of the pavement. Summary of the Invention

[0005] The purpose of the present invention is to provide a quantitative detection method for the optimal asphalt dosage of asphalt chip seal and a rolling device to solve the problems existing in the above-mentioned prior art. The rolling device can perform a rolling test on the asphalt chip seal and obtain the optimal asphalt spreading amount.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a method for quantitatively detecting the optimal asphalt dosage of an asphalt chip seal, comprising the following steps:

[0008] S1. Form asphalt chip seal with different asphalt spreading amounts and record the asphalt spreading amount a i ;

[0009] S2, forming a plurality of rutting plate specimens on the asphalt chip seal layer, leaving a partition between adjacent rutting plate specimens, and measuring a first volume V0 of the partition;

[0010] S3, placing a suitable test block in the compartment;

[0011] S4. Rolling the rutting plate specimen with a line rubbing device to perform a line rubbing test;

[0012] S5. After the line rubbing test is completed, the test block is taken out and the second volume V of the partition is measured. i ;

[0013] S6. Calculate the dynamic stability of the rutting plate specimen, and determine the optimal asphalt dosage of the asphalt chip seal according to the dynamic stability of the rutting plate specimen.

[0014] Preferably, in step S2, two rutting plate specimens are formed, the two rutting plate specimens are asphalt mixture rutting plate specimens with the same gradation and asphalt-stone ratio, and the two rutting plate specimens are located on both sides of the sample template.

[0015] Preferably, in step S4, after the pressure between the line kneading device and the rutting plate specimen reaches a preset pressure, the line kneading test is started, and after the rutting plate specimen is rolled back and forth for a preset number of times, the sample template used for forming the asphalt chip seal is removed and cooled to room temperature; then, the line kneading test of the rutting plate specimen is performed for a preset time;

[0016] In step S2 and step S5, the first volume and the second volume of the partition groove are measured by a sand filling method.

[0017] Preferably, in step S6, the dynamic stability of the rutting plate specimen is DS,

[0018] in,

[0019] Compared with the prior art, the present invention has achieved the following technical effects:

[0020] The present invention sets partitions between rutting plate test pieces. By measuring the volume ratio of the partitions before and after the test, the amount of asphalt overflow of the asphalt chip seal can be obtained from the side, and the asphalt overflow amount can be quantitatively analyzed.

[0021] The present invention can obtain the optimal asphalt spreading amount from a laboratory perspective by establishing a formula for the dynamic stability DS, the asphalt spreading amount, and the compartment volume ratio, thereby guiding actual construction and overcoming quality problems caused by using experience to control the asphalt spreading amount.

[0022] The present invention also provides an asphalt chip seal rolling device for implementing the above-mentioned method for quantitatively detecting the optimal asphalt dosage of asphalt chip seal, comprising a test box, a sample template being provided at the bottom of the test box, the sample template being used to form asphalt chip seals with different asphalt spreading amounts, and capable of forming a rutting plate specimen above the asphalt chip seal; a wire kneading device is also provided in the test box, the wire kneading device being located above the sample template, the wire kneading device being connected to a driving device, and the driving device being capable of driving the wire kneading device to roll the rutting plate specimen.

[0023] Preferably, a support is provided at the bottom of the test box, and the sample template is located on the support.

[0024] Preferably, a limiting screw is further provided on the side wall of the test box, and two limiting screws are provided. The two limiting screws are respectively located on both sides of the sample template to limit and fix the sample template.

[0025] Preferably, the line kneading device includes a roller bracket and a roller group, and a plurality of roller groups are rotatably mounted on the roller bracket. The roller groups correspond one-to-one to the rutting plate specimens, and the roller groups are used to roll the corresponding rutting plate specimens; wherein the circular uniformly distributed load generated by the rollers of the roller group does not produce overlapping.

[0026] Preferably, the driving device includes a linear motion mechanism and a loading mechanism, the linear motion mechanism is connected to the loading mechanism, and the loading mechanism is connected to the roller bracket, and can drive the roller group to move up and down to apply load to the corresponding rutting plate specimen, and the linear motion mechanism can drive the loading mechanism and the wire kneading device to move linearly to perform back and forth rolling on the corresponding rutting plate specimen.

[0027] Preferably, a pressure sensor is also provided on the roller assembly.

[0028] A wire kneading device is also provided in the test box of the present invention. The wire kneading device is located above the sample template. The sample template is connected to a driving device. The driving device can drive the wire kneading device to roll the rutting plate specimen to perform a wire kneading test. It can simulate the kneading effect of the rubber wheel during actual construction, effectively simulate the asphalt overflow effect in the asphalt gravel seal, and improve the accuracy of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 Schematic diagram of the process of asphalt chip seal detection method according to an embodiment of the present invention;

[0031] Figure 2 Schematic diagram of the structure of the asphalt chip seal rolling device in an embodiment of the present invention;

[0032] Among them: 1. Control device, 2. Drive device, 3. Test chamber, 4. Wire kneading device, 5. Support, 6. Sample template, 7. Limit screw. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The purpose of the present invention is to provide a quantitative detection method for the optimal asphalt dosage of asphalt chip seal and a rolling device to solve the problems existing in the above-mentioned prior art. The rolling device can perform a rolling test on the asphalt chip seal and obtain the appropriate asphalt spreading amount.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] Example 1

[0037] like Figure 2 As shown, this embodiment provides an asphalt chip seal rolling device, including a test box 3, a sample template 6 is provided at the bottom of the test box 3, and the sample template 6 is used to form asphalt chip seals with different asphalt spreading amounts, and can form rutting plate specimens above the asphalt chip seals; the test box 3 is also provided with a wire kneading device 4, the wire kneading device 4 is located above the sample template 6, and the wire kneading device 4 is connected to a driving device 2, and the driving device 2 can drive the wire kneading device 4 to roll the rutting plate specimen.

[0038] In this embodiment, a support 5 is provided at the bottom of the test box 3 , and the sample template 6 is located on the support 5 .

[0039] In this embodiment, two limit screws 7 are further provided on the side walls of the test chamber 3. The two limit screws 7 are located on either side of the sample template 6. The limit screws 7 can be tightened to limit and fix the sample template 6. The two limit screws 7 are located on the left and right sides of the sample template 6, respectively. In this embodiment, the left side is the left-hand side when facing the paper, and the right side is the right-hand side when facing the paper.

[0040] In this embodiment, the thread kneading device 4 includes a roller bracket and a roller assembly. Multiple roller assemblies are rotatably mounted on the roller bracket. Each roller assembly corresponds to a rutting plate specimen and is used to roll over the corresponding rutting plate specimen. The distance between the rollers of the roller assembly is determined based on the Saint-Venant principle. Specifically, the Saint-Venant principle states that the specific distribution of the load only affects the stress distribution near the load application area. In this embodiment, the distance between the rollers is determined based on the Saint-Venant material to ensure that the circular uniformly distributed loads generated by each roller do not overlap.

[0041] In this embodiment, the drive device 2 includes a linear motion mechanism and a loading mechanism. The linear motion mechanism is connected to the loading mechanism, which is in turn connected to the roller bracket, and can apply a load to the roller assembly, and thus to the rutting plate specimen. The linear motion mechanism can drive the loading mechanism and the wire kneading device 4 to move back and forth, thereby rolling the rutting plate specimen back and forth. The forward and backward direction is perpendicular to the paper. Both the linear motion mechanism and the loading mechanism are mature existing technologies in the field and can be selected based on specific work needs. For example, the linear motion mechanism can adopt a transmission screw mechanism, a linear motor mechanism, etc., while the loading mechanism can adopt a hydraulic cylinder, etc.

[0042] In this embodiment, a pressure sensor is further provided on the roller assembly, which can measure the pressure between the roller assembly and the rutting plate specimen.

[0043] In this embodiment, the asphalt chip seal rolling device also includes a control device 1, which mainly includes a master control display console, a pressure control module, a power control module, etc. The pressure control module is connected to the pressure sensor and the loading mechanism, and the power control module is connected to the linear motion mechanism for control; the sample template 6 can accommodate a common rutting plate specimen and the asphalt chip seal thickness.

[0044] Example 2

[0045] like Figure 1As shown, this embodiment also provides a method for quantitatively detecting the optimal asphalt dosage of an asphalt chip seal, using the above-mentioned asphalt chip seal rolling device, including the following steps:

[0046] Step 1: In the sample template 6 of the asphalt chip seal rolling device, form the asphalt chip seal with different asphalt spreading amounts, and record the asphalt spreading amount a i ;

[0047] Step 2: Form two asphalt mixture rutting plate specimens with the same gradation and asphalt-stone ratio, and place them on the left and right sides of the sample template 6;

[0048] Step 3: Leave a 5 cm partition between the two rutting plate specimens, measure the first volume V0 of the partition using the sand filling method, apply a release agent to a 5 cm wide × 30 cm long × 2 cm thick test piece, and insert it into the partition;

[0049] Step 4: Turn on the master control device 1. After the pressure between the line kneading device 4 and the rutting plate specimen reaches a preset pressure (preferably 0.7 MPa), start the line kneading test. After rolling back and forth for a preset number of times (preferably 24 times), remove the sample template 6 and the asphalt chip seal layer therein and the rutting plate specimen from the test chamber 3 and cool to room temperature. This step matches the actual work site rolling to ensure the experimental effect.

[0050] Step 5: Place the cooled sample template 6 and the asphalt chip seal and rutting plate specimens therein into the test chamber 3. After the rutting plate specimens are subjected to a line rubbing test for a preset time (preferably 1 hour), a 5 cm wide × 30 cm long × 2 cm thick test block is taken out and the second volume V of the partition groove at different asphalt spreading rates after the test is measured using the sand filling method. i ;

[0051] Step 6: The dynamic stability DS of the rutting plate specimen is:

[0052]

[0053] Among them, the relationship between volume ratio and asphalt spreading amount can be determined based on multiple tests as follows:

[0054]

[0055] DS and asphalt spreading amount a i The relationship between them can be determined by the above two formulas. In the future, the volume ratio can be omitted and the analysis can be performed directly based on the asphalt spreading amount to improve efficiency.

[0056] Where: DS—dynamic stability of asphalt mixture, times / mm; V i —Volume of the partition under different asphalt spreading amount after rutting test, m 3; V0—Volume of the asphalt mixture trough before rutting test, m 3 ;a i —Different asphalt spreading amount, kg / m 2 .

[0057] According to the Technical Specifications for Highway Asphalt Pavement Construction (JTG F40-2004), the asphalt spreading amount when DS reaches an inflection point is the optimal asphalt dosage.

[0058] Example 3

[0059] In this embodiment, based on the physical data of a secondary highway in the south, an asphalt gravel seal is used as a waterproof layer and a bonding layer on the base layer. The asphalt spreading amount a i =0.9kg / m 2 The lower layer uses AC-20 type matrix asphalt mixture with an oil-stone ratio of λ=4.3%.

[0060] Step 1: Spread the asphalt in the sample rolling device in the test room at a rate of 0.9 kg / m 2 Asphalt chip seal;

[0061] Step 2: Form two AC-20C asphalt mixture rutting plate specimens with the same gradation and asphalt-aggregate ratio, and place them on both sides of the specimen template 6;

[0062] Step 3: Leave a 5cm gap between the two rutting plate specimens and use the sand filling method to measure the first volume of the gap V0 = 0.00033m 3 ;

[0063] Step 4: Turn on the control device 1, and after the pressure between the wire kneading device 4 and the rutting plate specimen reaches 0.7 MPa, start the wire kneading test. After rolling back and forth 24 times, remove the sample template 6 and cool it to room temperature;

[0064] Step 5: Place the sample template 6 and perform a line rubbing test on the rutting plate specimen. Take out the 5cm wide × 30cm long × 2cm thick test piece and use the sand filling method to measure the pressure after the test. 2 The second volume of the partition under the asphalt spreading amount V1=0.00029m 3 ;

[0065] Step 6: Calculate the dynamic stability DS of the rutting plate specimen:

[0066]

[0067]

[0068] It meets the requirements; among them, 0.3569 is the correlation coefficient with the line rubbing test pressure, 0.8108 is the initial correlation coefficient, 5296.038, 6489.5 and 2885.65 are the correlation coefficients between the dynamic stability of the specimen and the asphalt spreading amount.

[0069] This specification uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A method for quantitatively determining the optimal asphalt dosage for asphalt chip seals, comprising the following steps: S1. Form asphalt chip seal with different asphalt spreading amounts in the sample template and record the asphalt spreading amount a. i ; S2, forming a plurality of rutting plate specimens on the asphalt chip seal layer, leaving a groove between adjacent rutting plate specimens, and measuring a first volume V0 of the groove; S3, placing a suitable test block in the compartment; S4. Rolling the rutting plate specimen with a line rubbing device to perform a line rubbing test; S5. After the line rubbing test is completed, the test block is taken out and the second volume V of the partition is measured. i ; S6. Calculating the dynamic stability of the rutting plate specimen, and determining the optimal asphalt dosage of the asphalt chip seal according to the dynamic stability of the rutting plate specimen; The dynamic stability of the rutting plate specimen is DS, in, 2. The method for quantitatively detecting the optimal asphalt dosage for asphalt chip seal according to claim 1, characterized in that: In the step S2, two rutting plate specimens are formed, and the two rutting plate specimens are asphalt mixture rutting plate specimens with the same gradation and asphalt-stone ratio.

3. The method for quantitatively detecting the optimal asphalt dosage for asphalt chip seal according to claim 1, characterized in that: In step S4, after the pressure between the line kneading device and the rutting plate specimen reaches a preset pressure, the line kneading test is started. After the rutting plate specimen is rolled back and forth for a preset number of times, the sample template is removed and cooled to room temperature. The line kneading test of the rutting plate specimen is then performed for a preset time. In step S2 and step S5, the first volume and the second volume of the partition groove are measured by a sand filling method.

4. An asphalt chip seal rolling device, characterized by: A method for quantitatively detecting the optimal asphalt dosage of an asphalt chip seal according to any one of claims 1 to 3 is provided, comprising a test box, wherein a sample template is provided at the bottom of the test box, wherein the sample template is used to form asphalt chip seals with different asphalt spreading amounts, and a rutting plate specimen can be formed above the asphalt chip seal; a wire kneading device is also provided in the test box, wherein the wire kneading device is located above the sample template, and the wire kneading device is connected to a driving device, and the driving device can drive the wire kneading device to roll the rutting plate specimen.

5. The asphalt chip seal rolling device according to claim 4, characterized in that: A support is provided at the bottom of the test box, and the sample template is located on the support.

6. The asphalt chip seal rolling device according to claim 5, characterized in that: The side walls of the test box are further provided with limiting screws, and two limiting screws are provided. The two limiting screws are respectively located on both sides of the sample template to limit and fix the sample template.

7. The asphalt chip seal rolling device according to claim 4, characterized in that: The wire kneading device includes a roller bracket and a roller group. Several roller groups are rotatably mounted on the roller bracket. The roller groups correspond to the rutting plate specimens one by one. The roller groups are used to roll the corresponding rutting plate specimens. The circular uniformly distributed loads generated by the rollers of the roller group do not overlap.

8. The asphalt chip seal rolling device according to claim 7, characterized in that: The driving device includes a linear motion mechanism and a loading mechanism. The linear motion mechanism is connected to the loading mechanism, and the loading mechanism is connected to the roller bracket, and can drive the roller group to move up and down to apply a load to the corresponding rutting plate specimen. The linear motion mechanism can drive the loading mechanism and the wire kneading device to move linearly to perform back and forth rolling on the corresponding rutting plate specimen.

9. The asphalt chip seal rolling device according to claim 8, characterized in that: The roller assembly is also provided with a pressure sensor.

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