A steel fiber pull-out test clamping device

Abstract

The utility model provides a kind of steel fiber pull-out test clamping device, including main rod and the bottom plate located below main rod, the clamping piece is arranged in the side of main rod, the top wall of bottom plate is fixed with four relative bottom plate central circumferentially evenly distributed riser, four The enclosure area of the riser between placement area.In the utility model, four circumferentially distributed risers are set on the bottom plate, the lead screw is penetrated and screwed on the riser, the different size concrete matrix of different specifications can be transversely limited by rotating four lead screws, two guide columns located on the outer periphery of concrete matrix are set on the bottom plate, the pressing block is gap set on the guide column, the pressing nut for extruding the pressing block is screw-connected on the top of guide column, the top of concrete matrix is limited when the pressing block is extruded, so that the different size concrete matrix of different specifications can be up and down limited, the above setting has the advantage of limiting and fixing different specifications of concrete matrix.

Description

Technical Field

[0001] This utility model relates to the field of concrete material testing technology, specifically a steel fiber pull-out test clamping device. Background Technology

[0002] Currently, steel fiber reinforced concrete is widely used in bridges, tunnels, high-rise buildings, and protective engineering due to its excellent crack resistance, toughness, and durability. The reinforcing effect of steel fibers in concrete mainly depends on the interfacial bonding performance between the steel fibers and the matrix. To study the bond-slip mechanism at the steel fiber-concrete interface, steel fiber pull-out tests are often used. These tests can obtain parameters such as the bond strength, friction, and mechanical anchoring performance between the steel fibers and the matrix, providing experimental basis for establishing interface constitutive models and optimizing concrete mix proportions.

[0003] However, existing clamping devices for testing are generally complex in structure and inconvenient to operate, which is not conducive to large-scale testing. They also have poor adaptability, making it difficult to limit and fix concrete substrates of different specifications, and they are not compatible with steel fibers of different lengths, diameters and shapes.

[0004] Therefore, there is an urgent need to design a pull-out test clamping device that is structurally sound, easy to operate, reliable in clamping, and compatible with steel fibers of different specifications, so as to improve the accuracy and efficiency of the test.

[0005] Therefore, this utility model provides a steel fiber pull-out test clamping device. Utility Model Content

[0006] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a steel fiber pull-out test clamping device to solve the problems mentioned in the background technology. This utility model has the advantages of limiting and fixing concrete substrates of different specifications, and also has the advantages of clamping and fixing steel fibers of different lengths, diameters and shapes.

[0007] To achieve the above objectives, this utility model is implemented through the following technical solution: a steel fiber pull-out test clamping device, comprising a main rod and a base plate located below the main rod, a clamping piece provided on one side of the main rod, four upright plates evenly distributed circumferentially relative to the center of the base plate fixedly provided on the top wall of the base plate, the four upright plates forming a placement area, a lead screw threaded through the surface of the upright plates, and two guide posts located outside the placement area screwed onto the top wall of the base plate, which are evenly distributed circumferentially relative to the center of the base plate, a pressure block sleeved on the guide post with gaps, and a clamping nut screwed onto the top of the guide post above the pressure block.

[0008] Furthermore, a stepped surface is provided on one side of the main rod, located at the bottom and opposite to the clamping piece. The clamping piece is square and is connected to the stepped surface by two rows of self-tapping screws located near the left and right sides respectively.

[0009] Furthermore, displacement gauge support frames are symmetrically arranged on both sides of the main rod, located above the clamping plates, and one side of the displacement gauge support frame is fixedly connected to the main rod by an anti-slip plate.

[0010] Furthermore, a washer is connected to one end of the lead screw located within the placement area, and a knob is fixedly connected to the other end of the lead screw.

[0011] Furthermore, the bottom of the guide post is screwed onto a reinforcing nut located below the base plate.

[0012] Furthermore, the pressure block has a trapezoidal structure and an oblong hole that is fitted onto the outside of the guide post.

[0013] Furthermore, a support column located on one side of the guide column is provided above the base plate, and a connecting screw that is screwed into the base plate is fixedly connected to the bottom end of the support column.

[0014] Furthermore, an upper connector is fixedly connected to the top of the main rod, and a lower connector is fixedly connected to the middle of the bottom of the base plate.

[0015] The beneficial effects of this utility model are as follows: In this invention, four vertical plates arranged in a ring are provided on the base plate, and screw rods are threaded through and connected to the vertical plates. By rotating the four screw rods, the concrete substrates of different sizes can be laterally limited. Two guide posts are provided on the base plate located on the outer periphery of the concrete substrate. Pressure blocks are fitted on the guide posts with gaps. The top of the guide posts is screwed with a clamping nut for pressing the pressure blocks. When the pressure blocks are pressed, they limit the top of the concrete substrate. Thus, the concrete substrates of different sizes can be vertically limited. The above arrangement has the advantage of limiting and fixing concrete substrates of different sizes.

[0016] In this invention, a main rod is provided, and a clamping plate is connected to one side of the main rod by two rows of self-tapping screws. When the self-tapping screws are tightened, the clamping plate will squeeze the steel fiber onto the main rod. This extrusion structure can clamp and fix steel fibers of different lengths, diameters and shapes. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a steel fiber pull-out test clamping device according to the present invention; Figure 2 for Figure 1 The main view; Figure 3 for Figure 1 The diagram at the bottom.

[0018] In the diagram: 1. Main rod; 11. Upper connector; 2. Base plate; 21. Lower connector; 3. Clamping plate; 4. Vertical plate; 5. Lead screw; 51. Washer; 52. Knob; 6. Guide post; 7. Pressure block; 71. Waist-shaped hole; 8. Pressure nut; 9. Displacement gauge support frame; 101. Anti-slip plate; 102. Reinforcing nut; 103. Support column; 1031. Connecting screw. Detailed Implementation

[0019] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0020] Please see Figures 1 to 3 This utility model provides a technical solution: a steel fiber pull-out test clamping device, including a main rod 1 and a base plate 2 located below the main rod 1. The main rod 1 is a straight plate structure, and a clamping piece 3 is provided on one side of the main rod 1. The function of the clamping piece 3 is to press the steel fiber onto the main rod 1. In a specific implementation, it is preferred that a stepped surface located at the bottom and opposite to the clamping piece 3 is opened on one side of the main rod 1. The clamping piece 3 is square and is connected to the stepped surface by two rows of self-tapping screws close to the left and right sides respectively. The space between the clamping piece 3 and the stepped surface is the space for placing the steel fiber. After the self-tapping screw is screwed into the stepped surface, it will squeeze the clamping piece 3, and the clamping piece 3 and the stepped surface will clamp the steel fiber.

[0021] The top wall of the base plate 2 is fixedly provided with four vertical plates 4 that are evenly distributed circumferentially relative to the center of the base plate 2. The center of this plate is opposite to the bottom end of the main rod 1. The four vertical plates 4 form a placement area for placing the concrete matrix to which the steel fiber is connected. A screw rod 5 is screwed through the surface of the vertical plate 4. Specifically, a threaded hole that matches the screw rod 5 is opened on the surface of the vertical plate 4. One end of the screw rod 5 located in the placement area is opposite to the concrete matrix. When the screw rod 5 is screwed, the screw rod 5 moves axially to the concrete matrix and presses against the side wall of the concrete matrix. At this time, the concrete matrix cannot move laterally.

[0022] Furthermore, a washer 51 is connected to one end of the lead screw 5 located in the placement area. The washer 51 and the lead screw 5 can be connected in a fixed manner, and the washer 51 replaces the lead screw 5 to directly contact the concrete substrate, thus avoiding damage to the concrete substrate by the lead screw 5. A knob 52 is fixedly connected to the other end of the lead screw 5. The knob 52 is a handheld component, and the lead screw 5 can be rotated manually by turning the knob 52.

[0023] The top wall of the base plate 2 is screwed with a guide post 6 located outside the placement area. The guide post 6 has a double-ended screw structure, and the base plate 2 has a threaded hole that fits the bottom of the guide post 6. In use, a reinforcing nut 102 located below the base plate 2 is screwed to the bottom of the guide post 6. Tightening the reinforcing nut 102 can effectively prevent the guide post 6 from loosening. There are two guide posts 6, which are evenly distributed circumferentially relative to the center of the base plate 2. In specific implementation, one guide post 6 is located on one side of two adjacent upright plates 4, and the other guide post 6 is located on one side of two other adjacent upright plates 4. A pressure block 7 is fitted on the guide post 6 with a gap. A clamping nut 8 located above the pressure block 7 is screwed to the top of the guide post 6. In use, the pressure block 7 is located above the concrete substrate. That is, when the clamping nut 8 is tightened, the clamping nut 8 will push the pressure block 7 to squeeze the upper surface of the concrete substrate, thereby limiting the upper and lower position of the concrete substrate.

[0024] The pressure block 7 has a trapezoidal structure and an oblong hole 71 that is sleeved on the outside of the guide post 6. The pressure block 7 has a lateral displacement under the guidance of the oblong hole 71. This arrangement makes it easy to adjust the contact position between the pressure block 7 and the top wall of the concrete substrate, and makes it easy to press the concrete substrate of different specifications.

[0025] In this embodiment, a support column 103 is provided above the base plate 2 on one side of the guide column 6. The bottom end of the support column 103 is fixedly connected to a screw rod 1031 that is screwed into the base plate 2. Specifically, a threaded hole adapted to the screw rod 1031 is opened on the base plate 2. The function of the support column 103 is to lift and limit the pressure block 7. The setting of the screw rod 1031 makes the height of the support column 103 adjustable, so as to prevent the pressure block 7 from tilting up and down when pressing the top wall of the concrete substrate.

[0026] In this embodiment, displacement gauge support frames 9 are symmetrically arranged on both sides of the main rod 1 above the clamping plate 3. One side of the displacement gauge support frame 9 is fixedly connected to the main rod 1 by an anti-slip plate 101. In specific implementation, the anti-slip plate 101 is fixedly connected to the main rod 1 by a self-tapping screw. The displacement gauge support frame 9 is used to install the displacement gauge. The displacement gauge support frame 9 adopts a common structure consisting of two semi-circular buckles combined by bolts. The displacement gauge is clamped between the two semi-circular buckles. The displacement gauge is used to record the range of steel fiber extraction.

[0027] In this embodiment, an upper connector 11 is fixedly connected to the top of the main rod 1. The upper connector 11 is a component that is fixedly connected to the main rod 1 and the upper testing machine. A lower connector 21 is fixedly connected to the middle of the bottom of the base plate 2. The lower connector 21 is a component that is fixedly connected to the lower testing machine. The specific structure of the upper connector 11 and the lower connector 21 is determined according to the connection structure on the testing machine, and will not be described in detail in this application.

[0028] Working principle: In use, first place the cubic concrete substrate in the placement space on the base plate 2, then place the upper end of the steel fiber above the concrete substrate between the clamp 3 and the step surface, ensuring that the steel fiber is approximately taut. Then, use self-tapping screws to lock the clamp 3. The clamp 3 and the step surface squeeze and fix the steel fiber. Manually control the rotation of each screw 5 by knob 52. When the screw 5 moves axially, it will push the concrete substrate through the shim 51. Visually, the steel fiber is approximately vertical (the purpose is to ensure that the steel fiber is aligned with the loading axis of the testing machine). Finally, tighten each screw 5 in turn. At this time, the concrete substrate is laterally limited. Lift the pressure block 7 and then move it laterally so that part of the lower end face of the pressure block 7 contacts the upper end face of the concrete substrate. Then, use a wrench to tighten the pressure nut 8. At this time, the lower end face of the pressure block 7 will simultaneously contact the top wall of the support column 103 and the top wall of the concrete substrate. The concrete substrate is locked by upper and lower limits. Limitation and fixation are achieved by hand-tightening screws 404 and protrusions 405. Finally, under the loading action of the testing machine, the steel fiber pull-out test can be carried out, and the displacement gauge records the pull-out range.

[0029] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A steel fiber pull-out test clamping device, comprising a main rod (1) and a base plate (2) located below the main rod (1), characterized in that, A clamping piece (3) is provided on one side of the main rod (1). Four upright plates (4) are fixedly provided on the top wall of the base plate (2) and are evenly distributed in the circumference relative to the center of the base plate (2). The four upright plates (4) form a placement area. A screw rod (5) is screwed through the plate surface of the upright plate (4). A guide post (6) located outside the placement area is screwed to the top wall of the base plate (2). There are two guide posts (6) and they are evenly distributed in the circumference relative to the center of the base plate (2). A pressure block (7) is fitted on the guide post (6) with a gap. A clamping nut (8) located above the pressure block (7) is screwed on the top of the guide post (6).

2. The steel fiber pull-out test clamping device according to claim 1, characterized in that: The main rod (1) has a stepped surface on one side located at the bottom and opposite to the clamp (3). The clamp (3) is square and is connected to the stepped surface by two rows of self-tapping screws close to the left and right sides respectively.

3. The steel fiber pull-out test clamping device according to claim 1, characterized in that: The main rod (1) is symmetrically provided with displacement gauge support frames (9) located above the clamping plate (3) on both sides. One side of the displacement gauge support frame (9) is fixedly connected to the main rod (1) through an anti-slip plate (101).

4. The steel fiber pull-out test clamping device according to claim 1, characterized in that: A gasket (51) is connected to one end of the lead screw (5) located in the placement area, and a knob (52) is fixedly connected to the other end of the lead screw (5).

5. The steel fiber pull-out test clamping device according to claim 1, characterized in that: The bottom of the guide post (6) is screwed to a reinforcing nut (102) located below the base plate (2).

6. The steel fiber pull-out test clamping device according to claim 1, characterized in that: The pressure block (7) has a trapezoidal structure and a waist-shaped hole (71) that is sleeved on the outside of the guide post (6).

7. The steel fiber pull-out test clamping device according to claim 6, characterized in that: A support column (103) is provided above the base plate (2) on one side of the guide column (6), and a connecting screw (1031) that is screwed into the base plate (2) is fixedly connected to the bottom end of the support column (103).

8. The steel fiber pull-out test clamping device according to claim 1, characterized in that: The top of the main rod (1) is fixedly connected to an upper connector (11), and the bottom of the base plate (2) is fixedly connected to a lower connector (21) in the middle.

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