Asphalt interlayer torsional shear strength testing device
By designing the asphalt shear strength test device between the sleeve and the torsion disc, the existing equipment is bulky, expensive and difficult to control the loading rate, and lightweight, easy to operate and high-precision tests are achieved to meet the on-site inspection needs.
Patent Information
- Application Number
- CN202422170282.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-04
- Publication Date
- 2025-07-01
- Estimated Expiration
- 2034-09-04
AI Technical Summary
Existing digital explicit twist shear testing equipment is bulky, expensive, and difficult to control the loading rate, which cannot meet the needs of on-site inspection.
A torsion shear strength test device between asphalt layer including sleeve and torsion disc is designed. Connecting holes are provided inside the sleeve, and annular slots, gradient sections and widened sections are designed on the outer surface to enhance the fixed connection and realize lightweight, easy to operate and high-precision tests.
It realizes lightweight and easy-to-operate torsion shear strength test, reduces equipment weight and cost, can manually control the loading rate, improves the test range and accuracy, and meets on-site inspection needs.
Smart Images
Figure CN223051079U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of road engineering test equipment, and particularly relates to a torsional shear strength test device for asphalt layers. Background Technique
[0002] The torsional shear strength test of asphalt layer bonding is a test method for applying torsional shear loading to asphalt mixture on the road site until the structure is damaged to obtain the torsional shear strength value. The relevant detection content has been included in the assessment scope of "Requirements for the Management of Highway and Waterway Test Detection Grades" (JT / T 1181-2018), and has a broad application scenario.
[0003] Currently, the mainly used equipment in the market is digital display torsional shear test equipment. The existing digital display torsional shear test equipment has the following problems: ① The equipment is bulky: The current mainstream test equipment weighs up to 95 kg, and basically no guide wheels are set for basic fixing. It is difficult to carry and is not conducive to conducting torsional shear tests at designated locations on the construction site. ② Expensive: The current mainstream equipment has a high selling price, and the transportation and maintenance costs are also high. ③ It is difficult to control the loading rate: The loading rate of the current mainstream equipment cannot be adjusted, and the control rates of different equipment are different, so manual control cannot be achieved. And the loading rate often does not meet the test requirements of the current specification "Code for Field Test of Highway Subgrade and Pavement" (JTG 3450-2019). Content of the Utility Model
[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. For this purpose, the utility model provides a torsional shear strength test device for asphalt layers.
[0005] A torsional shear strength test device for asphalt layers includes a sleeve and a torsion disc. The torsion disc is arranged below the sleeve and is used for bonding with the structure to be measured.
[0006] A connection hole is arranged inside the sleeve and is used for connecting with the torsion square head of a torque wrench.
[0007] An annular clamping groove, a tapered section and a widened section are sequentially arranged on the outer surface of the sleeve from top to bottom. The annular clamping groove and the widened section are used for fixedly connecting with the torque wrench. The outer diameter of the tapered section gradually increases from top to bottom and is connected to the widened section at the bottom. Two fixing holes are arranged in the diametrically opposite directions of the annular clamping groove, and fixing columns are arranged on the torsion square head. The fixing columns are connected with the fixing holes. Further specifically, in the above technical solution, the outer diameter of the sleeve is 47 mm and the height is 35 mm.
[0008] Further specifically, in the above technical solution, the annular clamping groove is located at a position 7 mm away from the top of the sleeve.
[0009] More specifically, in the above technical solution, the groove width of the annular groove is 4 mm, and the groove depth is 2 mm.
[0010] More specifically, in the above technical solution, the tapered section is located at a position 11 - 14 mm from the bottom of the sleeve.
[0011] More specifically, in the above technical solution, the outer diameter of the tapered section increases from 47 mm to 53 mm from top to bottom.
[0012] More specifically, in the above technical solution, the outer diameter of the widened section is 53 mm.
[0013] More specifically, in the above technical solution, the height of the widened section is 11 mm.
[0014] More specifically, in the above technical solution, the connection hole is a square hole with a size of 20 mm * 20 mm and a depth of 24 mm.
[0015] More specifically, in the above technical solution, the diameter of the torsion disc is 95 mm and the thickness is 14 mm.
[0016] Compared with the prior art, the embodiment of the present utility model has the following beneficial effects:
[0017] By designing the structures of the sleeve and the torsion disc, the device realizes a light, easy - to - operate and high - precision torsional shear strength test. The connection hole inside the sleeve is tightly combined with the torque - square head of the torque wrench, ensuring the accurate transmission of the loading force; the designs of the annular groove, tapered section and widened section on the outer surface of the sleeve enhance the fixed connection with the torque wrench, improving the stability and reliability of the test. At the same time, the fixing hole of the annular groove cooperates with the fixing post of the torque wrench, further preventing loosening and falling off during the test. Under the combined action of these features, the test device can meet the requirements of on - site detection, effectively reduce the equipment weight, lower the cost, and can manually control the loading rate, improve the test range and accuracy, so as to more accurately evaluate the torsional shear strength of the asphalt layer interface. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.
[0019] Figure 1 is a schematic cross - sectional structure diagram of the torsional shear strength test device for asphalt layer interface of the present utility model;
[0020] Figure 2 This is a three-dimensional structural schematic diagram of the torsional shear strength test device for the asphalt layer of the present utility model.
[0021] In the figure: 1. Sleeve; 2. Torsion disc; 3. Connecting hole; 4. Annular clamping groove; 5. Gradual change section; 6. Widening section; 7. Fixing hole. Specific embodiments
[0022] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.
[0023] In the description of the present utility model, it should be understood that for the orientation description, such as the orientation or positional relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model 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 to the present utility model.
[0024] In the description of the present utility model, unless otherwise clearly defined, words such as setting, installation, and connection should be understood in a broad sense. Those skilled in the art can reasonably determine the specific meanings of the above words in the present utility model in combination with the specific content of the technical solution.
[0025] In the description of the present utility model, referring to "one embodiment" or "some embodiments" etc. means that in one or more embodiments of the present utility model, specific features, structures, or characteristics described in connection with that embodiment are included. Thus, the statements "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments", etc. that appear in different places in this specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in another way. The terms "including", "comprising", "having" and their variants all mean "including but not limited to", unless otherwise specifically emphasized in another way.
[0026] Please refer to Figure 1-2, this application proposes a torsional shear strength test device for asphalt layers, including a sleeve 1 and a torsion disc 2. The torsion disc 2 is arranged below the sleeve 1 and is used to bond with the structure to be measured. A connection hole 3 is arranged inside the sleeve 1 and is used to connect with the square drive of a torque wrench. An annular clamping groove 4, a tapered section 5 and a widened section 6 are successively arranged on the outer surface of the sleeve 1 from top to bottom. The annular clamping groove 4 and the widened section 6 are used to be fixedly connected with the torque wrench. The outer diameter of the tapered section 5 gradually increases from top to bottom and the bottom is connected with the widened section 6. Two fixing holes 7 are arranged in the annular clamping groove 4 in the diametrically opposite directions. A fixing post is arranged on the square drive of the torque wrench, and the fixing post is connected with the fixing holes 7.
[0027] The torsion disc 2 is arranged below the sleeve 1, which is convenient for bonding with the structure to be measured (such as an asphalt layer), ensuring that the torsional shear force directly acts on the structure to be measured during the test, and improving the accuracy and reliability of the test.
[0028] The connection hole 3 arranged inside the sleeve 1 can be closely connected with the square drive of the torque wrench, realizing the quick and stable connection between the device and the torque wrench, and facilitating the operation.
[0029] The design of the annular clamping groove 4 and the widened section 6 on the outer surface of the sleeve 1 provides a multi-point fixed connection with the torque wrench, effectively preventing the loosening or falling off of the device and the torque wrench during the test, and improving the safety and stability of the test.
[0030] The outer diameter of the tapered section 5 gradually increases from top to bottom. This design not only enhances the structural strength of the sleeve 1, but also enables the torque wrench to have a smoother transition during connection, reduces stress concentration, and prolongs the service life of the device.
[0031] The fixing holes 7 on the annular clamping groove 4 cooperate with the fixing posts on the square drive of the torque wrench, realizing the quick positioning and fixing of the device and the torque wrench, simplifying the operation process, and improving the test efficiency.
[0032] Preferably, this device is integrally cast from low-carbon steel and is used as the torsion disc 2 to cooperate with common torque wrenches on the market for the torsional shear test of asphalt layer bonding.
[0033] This device can be used in cooperation with common torque wrenches on the market. Referring to the maximum range of 850 Nm, the measurement accuracy is 0.2%, and the holding force arm is increased by 100%. The test range and accuracy are greatly improved compared with the current mainstream equipment.
[0034] This device meets the relevant requirements of the "Field Test Procedures for Highway Subgrade and Pavement" (JTG 3450-2019), and the detection method is as follows:
[0035] ① Site preparation: Use a core drill or a small knife to drill a ring groove with a diameter φ of 100 mm at the measurement point. After cleaning and drying the surface of the measurement point, apply an adhesive to bond the measurement point to the torsion disk 2 provided by this device. Note that the adhesive should not enter the ring groove; after curing and complete solidification, prepare for the next test.
[0036] ② After the adhesive forms sufficient strength, install the torque wrench on the device.
[0037] ③ Set the relevant parameters of the torsion disk 2, including the design torque, unit, torsion shear direction, etc.
[0038] ④ Manually push the torsion bar uniformly so that the torsion bar rotates within 30 s ± 5 At the same time, it is necessary to ensure that the torsion bar torsion disk 2 is parallel to the surface of the test road surface or the specimen surface (the angle is less than ), and record the maximum torque when the test fails.
[0039] ⑤ Calculate the interlayer bond torsion shear strength according to the maximum torsion shear. The calculation formula is as follows. Record the failure state of the asphalt interlayer.
[0040]
[0041] Where: τ TBT is the interlayer bond torsion shear strength, kPa;
[0042] M—the maximum torque measured by the torque wrench, Nm;
[0043] D—the diameter of the torsion disk. In this application, it is taken as 95 mm.
[0044] Specifically, use this device to conduct an interlayer bond torsion shear test on the asphalt concrete simulated specimen at K0 + 360, No. 12, Zhongjing Road, and measure the torsion shear moment to be 228 Nm. According to the above calculation formula, the interlayer bond torsion shear strength of this simulated specimen is solved to be 1016 kPa.
[0045] In some embodiments, the outer diameter of the sleeve 1 is 47 mm and the height is 35 mm.
[0046] The main function of the sleeve 1 is to connect the torsion disk 2 and the torque wrench to make them an integral whole.
[0047] In some embodiments, the annular card slot 4 is located at a position 7 mm from the top of the sleeve 1.
[0048] The main function is to clamp the steel column of the torque wrench into the slot hole to fix the torsion disk 2 and the torque wrench so that they do not loosen due to shaking or stress.
[0049] In some embodiments, the slot width of the annular card slot 4 is 4 mm and the slot depth is 2 mm.
[0050] In some embodiments, the tapered section 5 is located at a position 11 - 14 mm from the bottom of the sleeve 1.
[0051] In some embodiments, the outer diameter of the tapered section 5 increases from 47 mm to 53 mm from top to bottom.
[0052] In some embodiments, the outer diameter of the widened section 6 is 53 mm.
[0053] In some embodiments, the height of the widened section 6 is 11 mm.
[0054] In some embodiments, the connecting hole 3 is a square hole with a size of 20 mm * 20 mm and a depth of 24 mm.
[0055] In some embodiments, the diameter of the torsion disk 2 is 95 mm and the thickness is 14 mm.
[0056] The main function of the torsion disk 2 is to bond with the asphalt structure after applying AB glue and conduct a torsional shear strength test.
[0057] The above - described 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 foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.
Claims
1. An asphalt interlayer torsional shear strength test device, characterized in that: include: A sleeve and a torsion plate, wherein the torsion plate is arranged below the sleeve and is used to bond with the structure to be measured; The sleeve is provided with a connecting hole inside, and the connecting hole is used to connect with the torque square head of the torque wrench; The outer surface of the sleeve is provided with an annular groove, a gradient section and a widened section in sequence from top to bottom. The annular groove and the widened section are used to be fixedly connected to the torque wrench. The outer diameter of the gradient section gradually increases from top to bottom and the bottom is connected to the widened section. The annular groove is provided with two fixing holes in the diametrically opposite directions. The torque square head is provided with a fixing column, and the fixing column is connected to the fixing hole.
2. The asphalt interlayer torsional shear strength testing device according to claim 1, characterized in that: The outer diameter of the sleeve is 47 mm and the height is 35 mm.
3. The asphalt interlayer torsional shear strength testing device according to claim 2, characterized in that: The annular groove is located at a position 7 mm away from the top of the sleeve.
4. The asphalt interlayer torsional shear strength testing device according to claim 3, characterized in that: The annular groove has a groove width of 4 mm and a groove depth of 2 mm.
5. The asphalt interlayer torsional shear strength testing device according to claim 2, characterized in that: The gradient section is located at a position where the sleeve is 11-14 mm away from the bottom.
6. The asphalt interlayer torsional shear strength testing device according to claim 5, characterized in that: The outer diameter of the gradient section increases from 47 mm to 53 mm from top to bottom.
7. The asphalt interlayer torsional shear strength testing device according to claim 6, characterized in that: The outer diameter of the widened section is 53 mm.
8. The asphalt interlayer torsional shear strength testing device according to claim 7, characterized in that: The height of the widened section is 11 mm.
9. The asphalt interlayer torsional shear strength testing device according to claim 1, characterized in that: The connecting hole is a square hole with a size of 20mm*20mm and a depth of 24mm.
10. The asphalt interlayer torsional shear strength testing device according to any one of claims 1 to 9, characterized in that: The torsion plate has a diameter of 95 mm and a thickness of 14 mm.