Rapid shearing device for asphalt mixture and bonding layer

Abstract

The utility model is suitable for the field of civil engineering material testing, provides a rapid shearing device for an asphalt mixture and a bonding layer, and aims to solve the problems that shearing cannot be performed along the weakest surface of a test piece, and load offset is easy to occur. The utility model discloses a rapid shearing device for an asphalt mixture and a bonding layer. The rapid shearing device is characterized by comprising a loading device, a test piece locking device, a base, a loading arc sheet and a handle, the number of the loading arc sheets is three, and the loading arc sheets are respectively arranged on the loading device, the test piece locking device and the base; the loading device comprises a loading seat, a cylindrical hole and a cylindrical pressing rod; a cylindrical pressing rod is fixedly connected to the top of the loading seat, cylindrical holes are formed in the two sides of the loading seat, base guide rods are arranged in the cylindrical holes, and the bottom ends of the base guide rods are connected with a base; the utility model solves the problems that the weakest surface of a test piece cannot be sheared in a single-sided direct shear test of the soil engineering, and the load offset is easy to occur.

Description

Technical Field

[0001] The utility model belongs to the field of civil engineering material testing, in particular to a rapid shearing device for asphalt mixture and bonding layer. Background Art

[0002] For asphalt pavement, it is of great practical significance to ensure that the asphalt mixture and bonding layer (such as adhesive layer, seal layer and other functional layers) have sufficient shear strength. The shear strength of the former is directly related to rutting, displacement and other diseases, while the shear strength of the latter is an important factor affecting the integrity of the pavement structure. At present, the current "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20) has not yet given a targeted test method for asphalt mixtures and bonding layers. Although the determination method of the shear strength of soil samples in geotechnical tests can be used for reference, such as single-sided direct shear and oblique shear tests, there are problems such as cumbersome parts and difficult to control the test - the shear surface of the geotechnical single-sided direct shear test is limited to the plane between the upper and lower boxes, and it is impossible to shear along the weakest surface of the specimen, which is prone to load offset problems and difficult to obtain effective test results; the shear failure surface of the oblique shear test is often inconsistent with the adhesive layer interface, and it is also difficult to obtain effective data.

[0003] In order to solve the above technical problems, the utility model designs a rapid shearing device for asphalt mixture and bonding layer. Utility Model Content

[0004] The utility model provides a rapid shearing device for asphalt mixture and bonding layer, aiming to solve the problem that shearing cannot be performed along the weakest surface of the test piece in a geotechnical single-plane direct shear test, and load deviation is easy to occur.

[0005] A rapid shearing device for asphalt mixture and bonding layer, characterized in that it comprises a loading device, a specimen locking device, a base, a loading arc piece and a handle; the number of the loading arc pieces is 3, and the loading arc pieces are respectively installed on the loading device, the specimen locking device and the base;

[0006] The loading device comprises a loading seat, a cylindrical hole and a cylindrical pressure rod; the top of the loading seat is fixedly connected to the cylindrical pressure rod, cylindrical holes are provided on both sides of the loading seat, a base guide rod is arranged in the cylindrical hole, and the bottom end of the base guide rod is connected to the base;

[0007] The specimen locking device includes a locking seat, a fixing rod, a guide through hole, and a guide rod. The fixing rod is fixedly connected to the top of the locking seat. A circular threaded hole is provided in the middle of the fixing rod. The handle passes through the circular threaded hole and is hinged to the locking seat. Guide through holes are provided at both ends of the locking seat. One end of the guide rod is connected to the guide through hole, and the other end is connected to the base.

[0008] Based on the above technical solution, the base includes a platform, the middle of the platform extends upward to form a workbench, the workbench is provided with a first opening and a second opening, the base guide rod is installed in the second opening, the top end of the base guide rod is connected to the loading seat through a cylindrical hole, and the first opening is connected to the guide rod.

[0009] Based on the above technical solution, the inner wall of the workbench is arc-shaped.

[0010] Based on the above technical solution, a spring is arranged in the cylindrical hole.

[0011] Based on the above technical solution, the inner diameter of the loading arc piece is 152.4 mm or 101.6 mm.

[0012] Based on the above technical solution, an arc hole is opened on the loading arc piece, and the loading arc piece is connected with the loading device, the specimen locking device and the base bolts through the arc hole.

[0013] Based on the above technical solution, the inner wall of the loading seat is arc-shaped.

[0014] Based on the above technical solution, the top of the handle is provided with one of a slot, a cross slot or a butterfly knob.

[0015] Based on the above technical solution, the material of the loading device, the specimen locking device and the base is steel or aluminum.

[0016] Based on the above technical solution, the loading arc piece is made of stainless steel.

[0017] Beneficial Effects

[0018] Compared with the prior art, the utility model has the following beneficial effects: the device can measure the shear strength of common asphalt mixtures, such as standard Marshall specimens (diameter 101.6mm) and large Marshall specimens (diameter 152.4mm), and can also be used to measure the shear strength of bonding layers. Both indoor prepared specimens and on-site pavement core samples can be measured, and the test can be completed by loading with a general mechanical testing machine. Since the test can be completed quickly and the failure surface is always a weak material interface, the test results are fast, accurate, intuitive, reliable, and effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only one embodiment of the utility model. For ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0020] Figure 1 : A schematic diagram of the structure of the utility model;

[0021] Figure 2 : A schematic diagram of the structure of the loading device of the utility model;

[0022] Figure 3 : A schematic diagram of the structure of the test piece locking device of the utility model;

[0023] Figure 4 : A schematic diagram of the structure of the base of the utility model;

[0024] Figure 5 : A schematic diagram of the structure of the loading arc piece of the utility model;

[0025] Figure 6 ; A schematic diagram of the structure of the combined test piece of the utility model;

[0026] In the accompanying drawings, there are a loading device 1, a loading seat 11, a cylindrical hole 12, a spring 13, a cylindrical pressure rod 14, a specimen locking device 2, a locking seat 21, a fixing rod 22, a guide through hole 23, a guide rod 24, a base 3, a platform 31, a workbench 32, a base guide rod 33, a first opening 34, a second opening 35, a loading arc piece 4, an arc piece hole 41, a handle 6, a first Marshall specimen 71, a second Marshall specimen 72, and an adhesive layer of asphalt 73. DETAILED DESCRIPTION

[0027] The utility model is further described below with reference to the accompanying drawings and examples:

[0028] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0029] In the description of the present invention, it should be noted that, 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, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply 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 on the present invention.

[0031] See also Figure 1 The utility model provides a technical solution: a rapid shearing device for asphalt mixture and bonding layer, characterized in that it includes a loading device 1, a specimen locking device 2, a base 3, a loading arc piece 4 and a handle 6; the number of the loading arc pieces 4 is 3, and the loading arc pieces 4 are respectively installed on the loading device 1, the specimen locking device 2, and the base 3.

[0032] like Figure 2 As shown, the loading device 1 comprises a loading seat 11, a cylindrical hole 12 and a cylindrical pressure rod 14; the top of the loading seat 11 is fixedly connected to the cylindrical pressure rod 14, and cylindrical holes 12 are provided on both sides of the loading seat 11. The cylindrical hole 12 is not through to the top, and a base guide rod 33 is arranged in the cylindrical hole 12, and the bottom end of the base guide rod 33 is connected to the base 3. A spring 13 is arranged in the cylindrical hole 12. The effect of moving downward during loading and rebounding in a balanced state during unloading is achieved.

[0033] like Figure 3 As shown, the specimen locking device 2 includes a locking seat 21, a fixing rod 22, a guide through hole 23, and a guide rod 24. The fixing rod 22 is fixedly connected to the top of the locking seat 21. A circular threaded hole is provided in the middle of the fixing rod 22. The handle 6 passes through the circular threaded hole and is hinged to the locking seat 21. Guide through holes 23 are provided at both ends of the locking seat 21. One end of the guide rod 24 is connected to the guide through hole 23, and the other end is connected to the base 3.

[0034] like Figure 4 As shown, the base 3 includes a platform 31, and the middle of the platform 31 extends upward to form a workbench 32. The workbench 32 is provided with a first opening 34 and a second opening 35. The second opening 35 is installed in the base guide rod 33. The top end of the base guide rod 33 is connected to the loading seat 11 through a cylindrical hole 12, and the first opening 34 is connected to the guide rod 24.

[0035] The platform 31 is provided with a counterweight to facilitate the balance of the device when loaded.

[0036] The inner wall of the workbench 32 is arc-shaped and is used for mounting the loading arc piece 4 .

[0037] The inner diameter of the loading arc piece 4 is 152.4 mm or 101.6 mm.

[0038] like Figure 5 As shown, an arc hole 41 is provided on the loading arc piece 4 , and the loading arc piece 4 is bolted to the loading device 1 , the specimen locking device 2 , and the base 3 through the arc hole 41 .

[0039] The inner wall of the loading seat 11 is arc-shaped and is used for mounting the loading arc piece 4 .

[0040] The top of the handle 6 is provided with one of a slot, a cross slot or a butterfly knob, which can be rotated by a screwdriver or manually. Thus, when the handle 6 is rotated, the locking seat 21 rises or falls along the guide rod 24 to achieve the installation or fixation of the test piece.

[0041] The material of the loading device 1, the specimen locking device 2, and the base 3 is one of steel or aluminum. Steel has a wide range of strengths, and steels of different strength grades can be selected as needed to meet various structural load-bearing requirements. Steel can undergo significant plastic deformation without breaking immediately after being subjected to force, which improves the safety and impact resistance of the structure. Steel can be processed by forging, rolling, welding, cutting, etc., and can adapt to various complex manufacturing processes. The light weight of aluminum helps to reduce the weight of the overall structure. Reducing weight can improve energy efficiency, reduce operating costs, and at the same time increase load capacity or maneuverability. Aluminum can form a dense aluminum oxide protective film in the air to prevent further oxidation and give it good corrosion resistance. This feature allows aluminum products to be used for a long time in most environments without additional coating, reducing maintenance costs and extending service life.

[0042] The loading arc piece 4 is made of stainless steel.

[0043] The loading arc pieces include two sets of large and small pieces, each set has three pieces, and the inner diameters are 152.4 mm and 101.6 mm respectively, which can be respectively installed on the base 3, the loading device 1 and the specimen locking device 2 by bolts.

[0044] The loading arc piece 4 is installed at the specimen locking device 2 and is staggered with the loading arc piece 4 installed at the loading device 1 to form a shear seam.

[0045] Marshall Specimen is a standard specimen used to evaluate the performance of asphalt mixtures such as asphalt concrete or asphalt macadam. It has important applications in road engineering, especially in the research, design and quality control of asphalt pavement materials. The Marshall test method is named after Bruce Marshall, an American engineer who proposed this test method for evaluating the compaction and stability of asphalt mixtures in the early 20th century.

[0046] 1. When conducting Marshall specimen shear strength test,

[0047] According to the diameter of the specimen to be tested, a loading arc piece 4 of a corresponding size is installed on the base 3, the loading device 1 and the specimen locking device 2, and the base 3, the loading device 1 and the specimen locking device 2 are assembled;

[0048] Rotate the handle 6 on the specimen locking device to raise the locking device 2, place the specimen horizontally on the arc-shaped notch, and tighten the handle 6 in the opposite direction to fix the specimen;

[0049] Place the assembled device in a mechanical testing machine, and make the loading rod of the testing machine correspond to the center of the cylindrical pressure rod at the top of the loading device;

[0050] Start the mechanical testing machine, apply compression load, achieve shearing of the specimen, and obtain the load-deformation curve;

[0051] Reading peak load F MAX The ratio of the cross-sectional area S of the specimen is the shear strength of the Marshall specimen. f S , that is

[0052] For indoor molding test pieces, prepare two Marshall test pieces of the same specifications, apply a preset amount of sticky asphalt on the lower surface of one of them and bond it with the other test piece in a hot state. When the sticky asphalt is hot asphalt material, the bonding is completed in a hot state; when it is emulsified asphalt, the bonding is completed before demulsification. After the hot asphalt on the lower surface cools down or the emulsified asphalt demulsifies, the following is obtained: Figure 6 The combined specimen of "first Marshall specimen 71 + adhesive layer asphalt 73 + second Marshall specimen 72" is shown. For pavement core specimens, they can be tested directly;

[0053] Rotate the handle 6 on the specimen locking device to raise the specimen locking device 2, place the combined specimen or the pavement coring specimen horizontally into the arc-shaped notch, adjust the position so that the bonding layer is aligned with the shear seam of the device, and tighten the handle 6 in the reverse direction to fix the specimen;

[0054] Place the assembled device in a mechanical testing machine, and make the loading rod of the testing machine correspond to the center of the cylindrical pressure rod 14 at the top of the loading device;

[0055] Start the mechanical testing machine, apply compression load, achieve shearing of the specimen, and obtain the load-deformation curve;

[0056] Reading peak load F MAX The ratio of the area S of the shear surface of the specimen is the shear strength of the bonding layer. f S , that is .

[0057] The present invention is described above by way of examples, but the present invention is not limited to the above specific embodiments, and any changes or modifications based on the present invention belong to the scope of protection required by the present invention.

Claims

1. A rapid shearing device for asphalt mixture and bonding layer, characterized in that: It comprises a loading device (1), a specimen locking device (2), a base (3), a loading arc piece (4) and a handle (6); the number of the loading arc pieces (4) is 3, and the loading arc pieces (4) are respectively mounted on the loading device (1), the specimen locking device (2) and the base (3); The loading device (1) comprises a loading seat (11), a cylindrical hole (12) and a cylindrical pressure rod (14); the top of the loading seat (11) is fixedly connected to the cylindrical pressure rod (14); cylindrical holes (12) are provided on both sides of the loading seat (11); a base guide rod (33) is provided in the cylindrical hole (12); and the bottom end of the base guide rod (33) is connected to the base (3); The specimen locking device (2) comprises a locking seat (21), a fixing rod (22), a guide through hole (23), and a guide rod (24); the fixing rod (22) is fixedly connected to the top of the locking seat (21); a circular threaded hole is provided in the middle of the fixing rod (22); the handle (6) passes through the circular threaded hole and is hinged to the locking seat (21); the locking seat (21) has guide through holes (23) at both ends; one end of the guide rod (24) is connected to the guide through hole (23), and the other end is connected to the base (3).

2. A rapid shearing device for asphalt mixture and bonding layer according to claim 1, characterized in that: The base (3) comprises a platform (31), the middle of the platform (31) extending upward to form a workbench (32), the workbench (32) being provided with a first opening (34) and a second opening (35), a base guide rod (33) being installed in the second opening (35), the top end of the base guide rod (33) being connected to the loading seat (11) via a cylindrical hole (12), and the first opening (34) being connected to the guide rod (24).

3. A rapid shearing device for asphalt mixture and bonding layer according to claim 2, characterized in that: The inner wall of the workbench (32) is arc-shaped.

4. A rapid shearing device for asphalt mixture and bonding layer according to claim 1, characterized in that: A spring (13) is arranged in the cylindrical hole (12).

5. The rapid shearing device for asphalt mixture and bonding layer according to claim 1, characterized in that: The inner diameter of the loading arc piece (4) is 152.4 mm or 101.6 mm.

6. A rapid shearing device for asphalt mixture and bonding layer according to claim 5, characterized in that: The loading arc piece (4) is provided with an arc piece hole (41), and the loading arc piece (4) is bolted to the loading device (1), the specimen locking device (2), and the base (3) via the arc piece hole (41).

7. The rapid shearing device for asphalt mixture and bonding layer according to claim 1, characterized in that: The inner wall of the loading seat (11) is arc-shaped.

8. The rapid shearing device for asphalt mixture and bonding layer according to claim 1, characterized in that: The top of the handle (6) is provided with one of a slot, a cross slot or a butterfly knob.

9. The rapid shearing device for asphalt mixture and bonding layer according to claim 1, characterized in that: The material of the loading device (1), the specimen locking device (2) and the base (3) is one of steel and aluminum.

10. The rapid shearing device for asphalt mixture and bonding layer according to claim 1, characterized in that: The loading arc piece (4) is made of stainless steel.

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