A concrete shrinkage testing device

Abstract

The utility model provides a kind of concrete shrinkage test device, it is related to concrete shrinkage test technical field, including measurement base plate;The upper end surface of the measurement base plate is embedded with dense ball, two dovetail grooves are further provided on measurement base plate, slidingly connected with sliding block in dovetail groove, fixedly connected with locating plate on sliding block, first threaded rod is inserted into locating plate, two groups of clamping plates are provided on first threaded rod, two groups of clamping plates are respectively clamped in locating plate both sides, and first threaded rod is inserted into first threaded cylinder;The utility model is equipped with adjusting plate and spring, according to the length size of test block, the elasticity of spring is adjusted by adjusting plate, ensure that the roller is enough pressure to exert on the two sides end surface of test block, ensure its righting ability to test block;The righting mechanism of adjustable is lacked in existing concrete shrinkage test device, the righting ability to some cuboid concrete block is limited when measuring, concrete may still deviate, and there is the problem of larger error.

Description

Technical Field

[0001] This utility model belongs to the field of concrete shrinkage testing technology, and more specifically, it relates to a concrete shrinkage testing device. Background Technology

[0002] Concrete shrinkage testing is a crucial testing item in the field of building materials. By conducting shrinkage tests on concrete test blocks, we can accurately grasp the law of volume change and provide key data support for the control of project quality.

[0003] A concrete shrinkage testing device, disclosed in publication number CN221765471U, belongs to the technical field of concrete shrinkage and expansion meters. It includes a test chamber and a dial gauge, with a worktable connected to the inner side of the test chamber. In this invention, an automatic straightening mechanism is incorporated. While the test specimen is being placed in the chamber, a fixed block is pushed. The movement of the fixed block moves a sliding rod, which in turn moves a telescopic rod and a first spring. The first spring, relying on its own elasticity, compresses a slider within a groove. The slider's movement then moves a compression plate. The compression plate and a limiting plate clamp and limit the concrete specimen, preventing it from potentially collapsing. The problem of horizontal displacement and difficulty in adjustment after clamping exists. Therefore, proper adjustment of the concrete position before the experiment can reduce errors, ensure experimental accuracy, and improve the accuracy of test results. The aforementioned shrinkage test device uses an automatic straightening mechanism to prevent the specimen from shifting, reducing errors. However, the elastic force generated by the first spring varies for specimens of different widths, resulting in different clamping forces. For some smaller specimens, the clamping force is relatively loose, making it impossible to effectively straighten the specimen, and large errors may still occur during the experiment. Utility Model Content

[0004] To address the aforementioned technical problems, this utility model provides a concrete shrinkage testing device. This addresses the issue that existing concrete shrinkage testing devices lack an adjustable straightening mechanism, have limited straightening capacity for certain rectangular concrete blocks during measurement, and may still experience displacement, resulting in significant errors.

[0005] This utility model provides a concrete shrinkage testing device, which is achieved by the following specific technical means:

[0006] A concrete shrinkage testing device includes a measuring base plate; densely packed ball bearings are semi-embedded on the upper surface of the measuring base plate, and two dovetail grooves are also formed on the measuring base plate. A slider is slidably connected in the dovetail grooves, and a positioning plate is fixedly connected to the slider. A first threaded rod is inserted through the positioning plate, and two sets of clamping plates are provided on the first threaded rod. The two sets of clamping plates are respectively clamped on both sides of the positioning plate. The first threaded rod passes through a first threaded cylinder, and the two form a helical transmission connection. A first handle is provided at one end of the first threaded rod. A dial indicator is fixedly mounted on one end of the measuring base plate. The dial indicator has... Measuring contact rod; a fixing frame is fixedly connected to both sides of the measuring base plate, and a second threaded cylinder is provided on the fixing frame. A second threaded rod is screwed inside the second threaded cylinder. A second handle is provided at one end of the second threaded rod, and the other end is inserted through and inserted into the adjusting plate. Two sets of clamping plates are provided on the second threaded rod, and the two sets of clamping plates are respectively clamped on both sides of the adjusting plate. A guide sleeve is provided on the adjusting plate, and a guide tube is slidably inserted inside the guide sleeve. A limit plate is fixedly connected to one end of the guide tube, and a spring is sleeved on the guide tube. The spring is located between the adjusting plate and the limit plate, and the spring is in a compressed state.

[0007] Furthermore, the measuring base plate has scale lines marked on the area between the positioning plate and the dial indicator, and the starting end of the scale lines is close to the dial indicator side.

[0008] Furthermore, a movable arm is hinged to the measuring base plate at a position near the starting end of the scale line, a pulley is rotatably connected to the movable arm, and a toggle plate is provided on the movable arm.

[0009] Furthermore, there are two sets of limiting plates, which are parallel to each other, and rollers are fixed on the opposite side of each set of limiting plates.

[0010] Furthermore, the measuring base plate is provided with a base on both sides, and a guide post is fixedly connected to the base, the guide post being slidably inserted into the guide sleeve.

[0011] Furthermore, the limiting plate has buckles at both ends, which are secured to the ends of the adjusting plate.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] 1. This utility model obtains the initial length of the concrete specimen before the shrinkage test by setting scale lines. By dividing the shrinkage amount obtained from the shrinkage test by the initial length, the shrinkage rate of the specimen in the length direction can also be obtained.

[0014] 2. This utility model uses rollers to clamp the test block on both sides for alignment. The rollers create rolling friction, which does not affect the deformation of the concrete and ensures the accuracy of the test data.

[0015] 3. This utility model, by setting an adjustment plate and a spring, adjusts the spring force according to the length of the test block, ensuring that the rollers apply sufficient pressure to both ends of the test block, thus guaranteeing their ability to straighten the test block. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0017] Figure 2 This is a top view of the present invention.

[0018] Figure 3 This utility model is in Figure 1 A magnified view of a portion of point A in the middle.

[0019] Figure 4 This utility model is in Figure 1 A magnified view of a section at point B.

[0020] Figure 5 This utility model is in Figure 1 A magnified view of a section at point C.

[0021] Figure 6 This utility model is in Figure 2 A magnified view of a section at point D.

[0022] In the diagram, the correspondence between component names and drawing numbers is as follows:

[0023] 1. Measuring base plate; 2. Ball bearing; 3. Dovetail groove; 4. Slider; 5. Positioning plate; 6. First threaded rod; 7. First threaded cylinder; 8. First handle; 9. Dial indicator; 10. Scale line; 11. Movable arm; 12. Pulley; 13. Actuating plate; 14. Fixing frame; 15. Second threaded cylinder; 16. Second threaded rod; 17. Second handle; 18. Adjusting plate; 19. Guide sleeve; 20. Guide tube; 21. Limiting plate; 22. Spring; 23. Roller; 24. Base; 25. Guide post; 26. Inverted buckle. Detailed Implementation

[0024] The embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of this utility model.

[0025] Example:

[0026] As attached Figure 1 To be continued Figure 6 As shown:

[0027] This utility model provides a concrete shrinkage testing device, including a measuring base plate 1; densely packed ball bearings 2 are semi-embedded on the upper surface of the measuring base plate 1, and two dovetail grooves 3 are also formed on the measuring base plate 1. A slider 4 is slidably connected in the dovetail grooves 3, and a positioning plate 5 is fixedly connected to the slider 4. A first threaded rod 6 is inserted through the positioning plate 5, and two sets of clamping plates are provided on the first threaded rod 6. The two sets of clamping plates are respectively clamped on both sides of the positioning plate 5. The first threaded rod 6 passes through a first threaded cylinder 7, and the two form a helical transmission connection relationship. A first handle 8 is provided at one end of the first threaded rod 6; a dial indicator 9 is fixedly installed at one end of the measuring base plate 1, and the dial indicator 9 has a measuring contact rod; the measuring base plate... 1. Fixed brackets 14 are fixedly connected to both sides. A second threaded cylinder 15 is provided on the fixed bracket 14. A second threaded rod 16 is screwed inside the second threaded cylinder 15. A second handle 17 is provided at one end of the second threaded rod 16, and the other end is inserted through and inserted into the adjusting plate 18. Two sets of clamping plates are provided on the second threaded rod 16, and the two sets of clamping plates are respectively clamped on both sides of the adjusting plate 18. A guide sleeve 19 is provided on the adjusting plate 18. A guide tube 20 is slidably inserted inside the guide sleeve 19. A limit plate 21 is fixedly connected to one end of the guide tube 20. A spring 22 is sleeved on the guide tube 20. The spring 22 is located between the adjusting plate 18 and the limit plate 21, and the spring 22 is in a compressed state.

[0028] Among them, such as Figure 2 As shown, the measuring base plate 1 has graduation lines 10 marked on the area between the positioning plate 5 and the dial indicator 9, with the starting end of the graduation lines 10 closer to the dial indicator 9; Figure 4 As shown, a movable arm 11 is hinged to the measuring base plate 1 near the starting end of the scale line 10. A pulley 12 is rotatably connected to the movable arm 11, and a toggle plate 13 is provided on the movable arm 11. Before measuring the concrete deformation, the concrete specimen is placed on the measuring base plate 1, supported at the bottom by the ball bearing 2. The first threaded rod 6 is rotated by the first handle 8, and the first threaded rod 6 is screwed in the first threaded cylinder 7. The positioning plate 5 pushes the specimen towards the side of the dial indicator 9 until the end of the specimen abuts against the pulley 12. At this time, the measuring contact rod of the dial indicator 9 is just in contact with the end face of the specimen. The scale aligned on the scale line 10 on the left side of the positioning plate 5 is read at this time. Subtracting the thickness of the positioning plate 5 itself, the initial length of the specimen is obtained. When measuring the deformation, the movable arm 11 is flipped by moving the toggle plate 13, so that the pulley 12 is removed from the end face of the specimen to avoid affecting the deformation of the concrete.

[0029] Among them, such as Figure 2As shown, there are two sets of limiting plates 21, which are parallel to each other, and rollers 23 are fixed on the opposite side of the two sets of limiting plates 21. The rollers 23 clamp the two end faces of the concrete test block to clamp and straighten it, so as to avoid skewing and ensure the test data. When the test block deforms, rolling friction is generated between its two end faces and the rollers 23. The rollers 23 straighten the test block and have little impact on the deformation of the concrete.

[0030] Among them, such as Figure 6 As shown, a base 24 is provided on both sides of the measuring base plate 1, and a guide post 25 is fixedly connected on the base 24. The guide post 25 slides through the guide sleeve 20. The guide post 25, in conjunction with the guide sleeve 19 and the guide sleeve 20, guides the horizontal movement of the adjusting plate 18 and the limiting plate 21, ensuring that the two sets of limiting plates 21 remain parallel to each other, so as to ensure the ability of the roller 23 to straighten the concrete test block.

[0031] Among them, such as Figure 6 As shown, the limiting plate 21 has buckles 26 at both ends, which are locked at the ends of the adjusting plate 18. Before the test, the adjusting plate 18 is opened to both sides, and the buckles 26 drive the two sets of limiting plates 21 to separate from each other, leaving enough space for the concrete test block on the measuring base plate 1.

[0032] The specific usage and function of this embodiment are as follows:

[0033] In this invention, before the test, the second threaded rod 16 is rotated by the second handle 17. The second threaded rod 16 is helically driven inside the second threaded cylinder 15, and the adjusting plate 18 is opened to both sides by the clamping plate. The two sets of limiting plates 21 are separated by the buckle 26, leaving enough space for the concrete test block on the measuring base plate 1. The concrete test block is placed on the measuring base plate 1, and the bottom is supported by the ball bearings 2. The second handle 17 is rotated in the opposite direction, and the two sets of adjusting plates 18 and limiting plates 21 move closer together. The rollers 23 contact the two end faces of the test block, and the rollers 22 apply pressure. Sufficient pressure is applied to straighten the test block on the measuring base plate 1. The first threaded rod 6 is rotated by the first handle 8, and the first threaded rod 6 is screwed in the first threaded cylinder 7. The positioning plate 5 pushes the test block towards the side of the dial indicator 9 until the end of the test block abuts against the pulley 12. At this time, the measuring contact rod of the dial indicator 9 is in contact with the end face of the test block. The scale aligned with the scale line 10 on the left side of the positioning plate 5 is read. Subtracting the thickness of the positioning plate 5 itself gives the initial length of the test block. Then, the concrete shrinks. The amount of shrinkage is measured by the dial indicator 9 and divided by the initial length to obtain the shrinkage rate of the test block in the length direction.

[0034] Any aspects of this utility model not described in detail are well-known technologies to those skilled in the art.

Claims

1. A concrete shrinkage testing device, comprising a measuring base plate (1); densely packed ball bearings (2) are semi-embedded on the upper surface of the measuring base plate (1), and two dovetail grooves (3) are also provided on the measuring base plate (1), a slider (4) is slidably connected in the dovetail grooves (3), a positioning plate (5) is fixedly connected to the slider (4), a first threaded rod (6) is inserted through the positioning plate (5), two sets of clamping plates are provided on the first threaded rod (6), the two sets of clamping plates are respectively clamped on both sides of the positioning plate (5), the first threaded rod (6) passes through a first threaded cylinder (7), and the two form a helical transmission connection relationship, a first handle (8) is provided at one end of the first threaded rod (6); a dial indicator (9) is fixedly installed at one end of the measuring base plate (1), and a measuring contact rod is provided on the dial indicator (9); characterized in that: The measuring base plate (1) is fixedly connected to both sides of a fixing frame (14). A second threaded cylinder (15) is provided on the fixing frame (14). A second threaded rod (16) is screwed inside the second threaded cylinder (15). A second handle (17) is provided at one end of the second threaded rod (16), and the other end is inserted through the adjusting plate (18). Two sets of clamping plates are provided on the second threaded rod (16). The two sets of clamping plates are respectively clamped on both sides of the adjusting plate (18). A guide sleeve (19) is provided on the adjusting plate (18). A guide sleeve (20) is slidably inserted inside the guide sleeve (19). A limit plate (21) is fixedly connected to one end of the guide sleeve (20). A spring (22) is sleeved on the guide sleeve (20). The spring (22) is located between the adjusting plate (18) and the limit plate (21), and the spring (22) is in a compressed state.

2. The concrete shrinkage testing device as described in claim 1, characterized in that: The measuring base plate (1) has a scale line (10) marked on the area between the positioning plate (5) and the dial indicator (9), and the starting end of the scale line (10) is close to the dial indicator (9).

3. The concrete shrinkage testing device as described in claim 2, characterized in that: A movable arm (11) is hinged to the measuring base plate (1) at a position near the starting end of the scale line (10). A pulley (12) is rotatably connected to the movable arm (11), and a toggle plate (13) is provided on the movable arm (11).

4. The concrete shrinkage testing device as described in claim 1, characterized in that: There are two sets of limiting plates (21), which are parallel to each other, and rollers (23) are fixed on the opposite side of the two sets of limiting plates (21).

5. The concrete shrinkage testing device as described in claim 1, characterized in that: The measuring base plate (1) is provided with a base (24) on both sides, and a guide post (25) is fixedly connected on the base (24). The guide post (25) slides through the guide sleeve (20).

6. The concrete shrinkage testing device as described in claim 1, characterized in that: The limiting plate (21) has buckles (26) at both ends, and the buckles (26) are locked at the ends of the adjusting plate (18).

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