Dial indicator clamp for steel bar bond stress test

Abstract

The utility model discloses a dial indicator clamp for a steel bar bond stress test. The dial indicator clamp comprises a measuring seat, a locking part and a plurality of leveling arms, the measuring seat is used for being installed on a reinforcing steel bar, can move relative to the reinforcing steel bar and is provided with an installation position for installing the dial indicator. The plurality of leveling arms are mounted on the measuring seat at intervals, can move relative to the measuring seat, and are pressed against the surface of the concrete test piece in the moving stroke to level the measuring seat, so that the axis of the measuring head of the dial indicator is parallel to the axis of the reinforcing steel bar; the locking part is arranged on the measuring seat and can lock the measuring seat on the reinforcing steel bar and unlock the measuring seat from the reinforcing steel bar. In the scheme, when the concrete test piece is broken, the dial indicator is fixed on the reinforcing steel bar through the measuring seat and the locking part and cannot fall off, so that the dial indicator is prevented from falling off and being damaged.

Description

Technical Field

[0001] This utility model relates to the field of rebar grip strength testing technology, specifically to a dial indicator clamp for rebar grip strength testing. Background Technology

[0002] Rebar bond strength testing devices are widely used in the measurement of concrete and grout materials, and in civil engineering construction, rebar bond strength is an important indicator.

[0003] CN202710409U discloses a variable-space rebar grip strength pull-out apparatus. The length of the screw entering the sleeve is adjusted according to the length of the reinforced concrete specimen, and the screw is fixed with a nut. After loading the reinforced concrete specimen, the fixing bolts are adjusted according to the size of the specimen to fix the clamping mechanism. A dial indicator is installed and brought into contact with the rebar cross-section. The variable-space rebar grip strength pull-out apparatus is placed on a tensile testing machine, with a clamping handle holding a supporting steel plate at the top and the exposed rebar of the specimen at the bottom. The tensile testing machine is then started until the rebar is pulled out, and the maximum grip strength and displacement at that moment are recorded to evaluate the grip strength between the rebar and the concrete.

[0004] In this patent, a dial indicator is fixed to a concrete specimen using fixing bolts. However, when pulling out the reinforcing steel, the concrete specimen is prone to cracking, causing the dial indicator to fall off and be damaged. Utility Model Content

[0005] The purpose of this utility model is to overcome the above-mentioned technical deficiencies and propose a dial indicator clamp for testing the bond strength of reinforcing bars. This solves the technical problem in the prior art where the dial indicator is fixed to the concrete specimen by fixing bolts, but when the reinforcing bar is pulled out, the concrete specimen is prone to cracking, causing the dial indicator to fall off and be damaged.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0007] This utility model provides a dial indicator clamp for testing the bond strength of reinforcing bars, comprising:

[0008] A measuring base for mounting on a reinforcing bar and movable relative to the reinforcing bar, and having a mounting position for mounting a dial indicator;

[0009] Multiple leveling arms are spaced apart and mounted on the measuring base, and are movable relative to the measuring base. During their movement, they press against the surface of the concrete specimen to level the measuring base, so that the axis of the dial indicator's measuring head is parallel to the axis of the reinforcing bar; and

[0010] A locking part is provided on the measuring seat, which can lock the measuring seat to the reinforcing bar and unlock the measuring seat from the reinforcing bar.

[0011] In some embodiments, the measuring seat is provided with an adjustment channel for the reinforcing bar to pass through, and the diameter of the adjustment channel is larger than the diameter of the reinforcing bar, and a locking screw hole is provided along its radial direction;

[0012] The locking part includes a locking bolt, one end of which is screwed into the locking bolt hole and can extend into the adjustment channel to press against the reinforcing bar.

[0013] In some embodiments, a plurality of locking screw holes are provided, and the plurality of locking screw holes are spaced apart along the axial direction of the adjustment channel. A plurality of locking bolts are provided, and the plurality of locking bolts are respectively provided in the plurality of locking screw holes.

[0014] In some embodiments, the dial gauge fixture for the rebar bond strength test further includes a guide cylinder, which is mounted on the measuring base and located on one side of the adjustment channel and communicates with the adjustment channel.

[0015] In some embodiments, the measuring seat is provided with a mounting channel, and the sidewall of the mounting channel is provided with mounting screw holes radially thereon;

[0016] The dial indicator fixture for the rebar gripping force test also includes a mounting bolt, one end of which is screwed into the mounting bolt hole and can extend into the mounting channel to press against the dial indicator.

[0017] In some embodiments, the dial indicator fixture for testing the bond strength of the reinforcing bar further includes a flexible pad, which is disposed at one end of the mounting bolt that extends into the mounting screw hole.

[0018] In some embodiments, the mounting channels are provided in multiple ways, and the multiple mounting channels are symmetrically distributed on the measuring base.

[0019] In some embodiments, the measuring seat is provided with a plurality of leveling screw holes, and the plurality of leveling screw holes are spaced apart;

[0020] The leveling arm is a leveling screw, and multiple leveling screws are respectively provided in multiple leveling screw holes.

[0021] In some embodiments, the leveling screw holes are symmetrically arranged on the measuring seat.

[0022] In some embodiments, the measuring seat is provided with anti-slip stripes.

[0023] Compared with the prior art, the dial indicator fixture for testing the bond strength of reinforcing bars provided by this utility model first fixes the dial indicator to the measuring base through the mounting part, then places the measuring base on the reinforcing bar, and simultaneously levels the measuring base through the leveling part, so that the measuring head of the dial indicator presses against the surface of the concrete specimen and keeps its axis parallel to the axis of the reinforcing bar to ensure measurement accuracy; then the reinforcing bar is pulled out, and the measuring base moves synchronously during the pulling and moving of the reinforcing bar. At this time, the measuring head of the dial indicator is compressed by the concrete specimen and the measurement is performed. Even if the concrete specimen breaks during this process, the dial indicator is fixed to the reinforcing bar by the measuring base and the locking part and will not fall, avoiding damage to the dial indicator. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the dial indicator fixture for testing the bond strength of reinforcing bars provided in this embodiment of the utility model;

[0025] Figure 2 yes Figure 1 Exploded view of the dial gauge fixture used for testing the bond strength of reinforcing steel bars.

[0026] Explanation of reference numerals in the attached figures:

[0027] 1. Measuring base; 1a. Adjustment channel; 1b. Locking screw hole; 1c. Mounting channel; 1d. Mounting screw hole; 1e. Leveling screw hole; 2. Mounting bolt; 3. Leveling arm; 31. Leveling screw; 4. Locking part; 41. Locking bolt; 5. Guide cylinder. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0029] To address the technical problem in existing technologies where dial indicators are fixed to concrete specimens with bolts, which can easily lead to cracking of the concrete specimens and damage to the dial indicator when the reinforcing bars are pulled out, this invention provides a dial indicator clamp for testing the bond strength of reinforcing bars. Even if the concrete specimen cracks during the measurement process, the dial indicator remains fixed to the reinforcing bar via the measuring seat and locking part, preventing it from falling and thus avoiding damage.

[0030] Please see Figure 1 and Figure 2 , Figure 1 and Figure 2This is a schematic diagram of the structure of a dial indicator clamp for testing the bond strength of reinforcing bars in one embodiment of the present invention. The dial indicator clamp for testing the bond strength of reinforcing bars includes a measuring base 1, a locking part 4, and multiple leveling arms 3. The measuring base 1 is used to install on the reinforcing bar and can move relative to the reinforcing bar, and has a mounting position for installing the dial indicator. Multiple leveling arms 3 are installed at intervals on the measuring base 1 and can move relative to the measuring base 1. During the movement stroke, they press against the surface of the concrete specimen to level the measuring base, so that the axis of the measuring head of the dial indicator is parallel to the axis of the reinforcing bar. The locking part 4 is provided on the measuring base 1 and can lock the measuring base 1 to the reinforcing bar and can unlock the measuring base 1 from the reinforcing bar.

[0031] In the dial indicator fixture for testing the bond strength of reinforcing bars provided by this utility model, the dial indicator is first fixed on the mounting position of the measuring base 1, and then the measuring base 1 is placed on the reinforcing bar. At the same time, the measuring base 1 is leveled by the leveling arm 3 so that the measuring head of the dial indicator presses against the surface of the concrete specimen and its axis is kept parallel to the axis of the reinforcing bar to ensure measurement accuracy. Then, the reinforcing bar is pulled out. During the pulling and moving of the reinforcing bar, the measuring base 1 moves synchronously. At this time, the measuring head of the dial indicator is compressed by the concrete specimen and the measurement is performed. Even if the concrete specimen breaks during this process, the dial indicator is fixed to the reinforcing bar by the measuring base 1 and the locking part 4 and will not fall off, avoiding damage to the dial indicator.

[0032] It should be noted that the specific configuration of the locking part 4 is not limited, as long as it can enable the locking and unlocking of the measuring seat 1 on the reinforcing bar. In one embodiment, the locking part 4 is configured as two elastically telescopic clamps to clamp the measuring seat 1 onto the reinforcing bar. In another embodiment, the locking part 4 is configured as a binding rope, and a rope hole is provided on the measuring seat 1 to enable the mounting and dismounting of the measuring seat 1 from the reinforcing bar.

[0033] In this embodiment, the measuring seat 1 is provided with an adjustment channel 1a, which is used for the insertion of reinforcing bars. The diameter of the adjustment channel 1a is larger than the diameter of the reinforcing bars, and a locking screw hole 1b is provided along its radial direction. The locking part 4 includes a locking bolt 41, one end of which is screwed into the locking screw hole 1b and can extend into the adjustment channel 1a to press against the reinforcing bars.

[0034] In this design, the reinforcing bar is inserted into the adjustment channel 1a of the measuring base 1. Since the diameter of the adjustment channel 1a is larger than the outer diameter of the reinforcing bar, the measuring base 1 can be leveled to ensure measurement accuracy. After leveling, the locking bolt 41 is tightened and pressed against the reinforcing bar to lock the measuring base 1 onto the reinforcing bar. When unlocking is needed, the locking bolt 41 is loosened, making the operation simple and convenient.

[0035] In one embodiment, multiple locking screw holes 1b are provided, and the multiple locking screw holes 1b are spaced apart along the axial direction of the adjustment channel 1a. Multiple locking bolts 41 are provided, and the multiple locking bolts 41 are respectively provided in the multiple locking screw holes 1b.

[0036] In this embodiment, multiple locking screw holes 1b are provided at circumferential intervals along the adjustment channel 1a, and multiple locking bolts 41 are provided accordingly to improve the locking stability of the measuring seat 1. Specifically, in this solution, two locking screw holes 1b are symmetrically provided.

[0037] In one embodiment, the dial gauge fixture for the rebar grip strength test further includes a guide cylinder 5, which is installed on the measuring base 1 and located on one side of the adjustment channel 1a and connected to the adjustment channel 1a.

[0038] In this embodiment, a guide cylinder 5 is also provided at one end of the adjustment channel 1a to guide the reinforcing bars and improve the convenience of reinforcing bar installation.

[0039] It should be noted that a mounting part is provided at the mounting position to fix the dial indicator. The specific form of the mounting part is not limited, as long as it can fix the dial indicator on the measuring base 1. In one embodiment, the mounting part is set in the form of a plug-in screw hole, and an external thread is provided on the measuring fixing rod of the dial indicator to screw the dial indicator into the plug-in screw hole. In another embodiment, the mounting part is set in the form of a flexible and telescopic clamp to hold the dial indicator.

[0040] In this embodiment, the measuring base 1 is provided with an installation channel 1c, and the side wall of the installation channel 1c is provided with an installation screw hole 1d along its radial direction; the dial gauge fixture for the rebar gripping force test also includes an installation bolt 2, one end of which is screwed into the installation screw hole 1d and can extend into the installation channel 1c to press against the dial gauge.

[0041] In this scheme, when installing the dial indicator, the measuring rod of the dial indicator is inserted into the installation channel 1c. After the measuring head of the dial indicator presses against the surface of the concrete specimen, the mounting bolt 2 is tightened so that the mounting bolt 2 presses against the measuring rod of the dial indicator, thereby fixing the dial indicator. The operation is convenient and the structure is stable and reliable.

[0042] In one embodiment, the dial gauge fixture for testing the bond strength of the reinforcing bar also includes a flexible pad, which is located at the end of the mounting bolt 2 that extends into the mounting screw hole 1d.

[0043] In this embodiment, a flexible pad is provided at one end of the mounting bolt 2 that presses against the measuring fixing screw of the dial indicator to prevent the mounting bolt 2 from damaging the dial indicator and to further extend the service life of the dial indicator. Specifically, the flexible pad is a rubber pad.

[0044] In one embodiment, multiple mounting channels 1c are provided, and the multiple mounting channels 1c are symmetrically distributed on the measuring base 1.

[0045] In this embodiment, multiple mounting channels 1c are correspondingly provided on the measuring base 1, thereby enabling the installation of multiple dial indicators. Simultaneous detection by multiple dial indicators improves measurement accuracy. Furthermore, the symmetrical arrangement of the multiple dial indicators enhances stability. Specifically, in this solution, two mounting channels 1c are symmetrically arranged.

[0046] It should be noted that the specific configuration of the leveling arm 3 is not limited, as long as it can achieve the leveling of the measuring base 1. In one embodiment, the leveling arm 3 is configured as a telescopic rod, with multiple telescopic rods spaced apart on the measuring base 1, and the measuring base 1 is leveled by adjusting the length of the telescopic rods. In another embodiment, the leveling arm 3 is configured as a multi-segment leveling rod, and leveling is achieved by adding or removing leveling rods.

[0047] In this embodiment, the measuring seat 1 is provided with multiple leveling screw holes 1e, which are spaced apart; the leveling arm is a leveling screw 31, and the multiple leveling screws 31 are respectively provided in the multiple leveling screw holes 1e.

[0048] In this design, the leveling arm 3 is configured as a leveling screw 31. Leveling of the measuring base 1 is achieved by tightening or loosening the leveling screw 31, making operation simple and convenient. Furthermore, to further improve the ease of leveling, a level can also be installed on the measuring base 1. It should be noted that the multiple leveling screw holes 1e extend in the same direction.

[0049] In one embodiment, the leveling screw holes 1e are symmetrically arranged on the measuring seat 1.

[0050] In this embodiment, the leveling screw holes 1e are symmetrically arranged, so that the leveling screws 31 can be symmetrically arranged accordingly, thereby improving the leveling accuracy. Specifically, in this scheme, two leveling screw holes 1e are symmetrically arranged, with the two leveling screw holes 1e extending in the same direction and located inside the two mounting channels 1c and outside the adjustment channel 1a. In addition, the adjustment channel 1a, the mounting channel 1c, and the leveling screw holes 1e all extend in the same direction.

[0051] In one embodiment, the measuring seat 1 is provided with anti-slip stripes.

[0052] In this embodiment, anti-slip stripes are provided on the surface of the measuring base 1 to facilitate installation by operators and improve convenience.

[0053] To better understand this utility model, the following is combined with... Figure 1 and Figure 2 The technical solution of this utility model is described in detail below:

[0054] The workflow for the dial gauge fixture used in the rebar bond strength test in this plan is as follows:

[0055] Pass the measuring rod of the dial indicator through the mounting channel 1c of the measuring base 1, and then tighten the mounting bolt 2 to fix the dial indicator to the measuring base 1. Then, place the adjustment channel 1a of the measuring base 1 onto the reinforcing bar, so that the measuring head of the dial indicator presses against the surface of the concrete specimen. At the same time, adjust the leveling screw 31 until the axis of the measuring head of the dial indicator is parallel to the axis of the reinforcing bar. Then loosen the leveling screw 31 so that it is away from the surface of the concrete specimen. Then pull the reinforcing bar. During the pulling and moving of the reinforcing bar, the measuring base 1 moves synchronously. At this time, the measuring head of the dial indicator is compressed by the concrete specimen and measures. Even if the concrete specimen breaks during this process, the dial indicator is fixed to the reinforcing bar by the measuring base 1 and the locking part 4 and will not fall, thus avoiding damage to the dial indicator.

[0056] The specific embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model. Any other corresponding changes and modifications made based on the technical concept of this utility model should be included within the scope of protection of the claims of this utility model.

Claims

1. A dial indicator clamp for testing the bond strength of reinforcing bars, characterized in that, include: A measuring base for mounting on a reinforcing bar and movable relative to the reinforcing bar, and having a mounting position for mounting a dial indicator; Multiple leveling arms are installed at intervals on the measuring base and can move relative to the measuring base. During their movement, they press against the surface of the concrete specimen to level the measuring base so that the axis of the dial indicator's measuring head is parallel to the axis of the reinforcing bar. and A locking part is provided on the measuring seat, which can lock the measuring seat to the reinforcing bar and unlock the measuring seat from the reinforcing bar.

2. The dial indicator fixture for testing the bond strength of reinforcing bars according to claim 1, characterized in that, The measuring base is provided with an adjustment channel for the reinforcing bar to pass through, and the diameter of the adjustment channel is larger than the diameter of the reinforcing bar, and a locking screw hole is provided along its radial direction; The locking part includes a locking bolt, one end of which is screwed into the locking bolt hole and can extend into the adjustment channel to press against the reinforcing bar.

3. The dial indicator fixture for testing the bond strength of reinforcing bars according to claim 2, characterized in that, The locking screw holes are provided in multiple ways, and the multiple locking screw holes are spaced apart along the axial direction of the adjustment channel. The locking bolts are provided in multiple ways, and the multiple locking bolts are respectively provided in the multiple locking screw holes.

4. The dial indicator fixture for testing the bond strength of reinforcing bars according to claim 2, characterized in that, The dial gauge fixture for the rebar grip strength test also includes a guide cylinder, which is installed on the measuring base and located on one side of the adjustment channel, and is connected to the adjustment channel.

5. The dial indicator fixture for testing the bond strength of reinforcing bars according to claim 1, characterized in that, The measuring base is provided with an installation channel, and the sidewall of the installation channel is provided with installation screw holes along its radial direction; The dial indicator fixture for the rebar gripping force test also includes a mounting bolt, one end of which is screwed into the mounting bolt hole and can extend into the mounting channel to press against the dial indicator.

6. The dial indicator fixture for testing the bond strength of reinforcing bars according to claim 5, characterized in that, The dial indicator fixture for the rebar gripping force test also includes a flexible pad, which is located at one end of the mounting bolt that extends into the mounting bolt hole.

7. The dial indicator fixture for testing the bond strength of reinforcing bars according to claim 5, characterized in that, The mounting channel is provided in multiple ways, and the multiple mounting channels are symmetrically distributed on the measuring base.

8. The dial indicator fixture for testing the bond strength of reinforcing bars according to claim 1, characterized in that, The measuring base is provided with multiple leveling screw holes, which are spaced apart. The leveling arm is a leveling screw, and multiple leveling screws are respectively provided in multiple leveling screw holes.

9. The dial indicator fixture for testing the bond strength of reinforcing bars according to claim 8, characterized in that, The leveling screw holes are symmetrically arranged on the measuring base.

10. The dial indicator fixture for testing the bond strength of reinforcing bars according to claim 1, characterized in that, The measuring base is equipped with anti-slip stripes.

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