A rock uniaxial compressive strength measuring device

Abstract

The application relates to the technical field of rock compressive strength measurement, in particular to a rock uniaxial compressive strength measurement device, which comprises a support frame, a clamping mechanism for clamping a rock sample is fixed to the lower part of the support frame, an impact head is connected to the middle part of the support frame, an impact mechanism for applying impact force to the impact head is connected to the upper part of the support frame, when the impact test is carried out, the clamping mechanism clamps the rock sample, a workman does not need to provide a counterforce to the measurement device, and the bottom end of the impact head is provided with at least one downward protruding arc-shaped convex rib, the lower end of the arc-shaped convex rib is in linear contact with the upper end of the rock sample, the influence of the measured position on the measurement result is reduced, and the discreteness of the measurement data is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of rock compressive strength measurement, in particular to a rock uniaxial compressive strength measurement device. Background Art

[0002] The rebound test is a testing method used to determine rock classification and rock anisotropy and predict the uniaxial compressive strength of rock. It is favored by testing units for its advantages of being light, fast, having little impact on the structure, and having a fast testing speed. It is also a common method used by construction units to quickly check the strength of concrete or rock.

[0003] The rebound test needs to be measured using a rebound hammer. The basic principle of the rebound hammer is to use a spring to drive a heavy hammer to hit the impact head in vertical contact with the surface of the rock sample with constant kinetic energy, causing the local rock sample surface to deform and absorb part of the energy, and the other part of the energy is converted into the rebound kinetic energy of the heavy hammer. When the rebound kinetic energy is completely converted into potential energy, the heavy hammer rebounds to the maximum distance, and the instrument displays the maximum rebound distance of the heavy hammer in the name of the rebound value.

[0004] The impact head of existing rebound hammers is hemispherical at the end that contacts the rock sample. This creates point contact with the rock surface, resulting in a small test area. However, the strength values ​​at different locations on the rock sample vary due to the degree of surface weathering. Using this point contact method for uniaxial strength testing of rock samples can lead to significant dispersion in the test data due to the location of the test point. Furthermore, most existing rebound hammers are handheld, requiring manual grip to provide a reaction force during the impact process. However, at the moment of impact, the reaction force provided by the operator may be less than the impact force, causing relative motion between the hammer and the rock sample, adversely affecting the test results. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the existing rebound hammer needs to rely on manpower to provide reaction force, and the impact head and the rock sample are in point contact, resulting in large discreteness of the test data.

[0006] In order to solve the above technical problems, the purpose of the present invention is to provide a rock uniaxial compressive strength measuring device, including a support frame, a clamping mechanism for clamping a rock sample is fixed at the lower part of the support frame, an impact head is connected to the middle part of the support frame, and an impact mechanism for applying impact force to the impact head is connected to the upper part of the support frame, and the bottom end of the impact head is provided with at least one downwardly protruding arc-shaped rib, and the lower end of the arc-shaped rib is in linear contact with the upper end of the rock sample.

[0007] As a preferred embodiment, the clamping mechanism includes a transverse guide rail fixed to the lower part of the support frame, the transverse guide rail is located above the rock sample, and a first clamping member and a second clamping member are slidably provided on the transverse guide rail and arranged relatively spaced apart from each other on the left and right sides. The rock sample is set between the first clamping member and the second clamping member, and the first clamping member and the second clamping member are close to each other to clamp the rock sample, or the first clamping member and the second clamping member are moved away from each other to release the rock sample.

[0008] As a preferred embodiment, the clamping mechanism includes a screw arranged parallel to the transverse guide rail, the first end of the screw is screwed to the first clamping member, the second end of the screw is screwed to the second clamping member, and the external thread of the first end of the screw and the external thread of the second end of the screw have opposite rotation directions.

[0009] As a preferred solution, a mounting plate is fixed to the upper portion of the support frame, the mounting plate is fixedly connected to a plurality of guide posts extending vertically downward, and the impact head is connected to the lower end of each of the guide posts;

[0010] The impact mechanism includes an impact hammer and a tension spring detachably connected to the lower end of the mounting plate. The upper end of the impact head is provided with a spring receiving groove with an upward opening. The lower end of the tension spring is fixedly connected to the bottom wall of the spring receiving groove. The upper end of the tension spring is fixedly connected to the lower end of the impact hammer. The tension spring pulls the impact hammer removed from the mounting plate to move downward so that the lower end of the impact hammer abuts against the upper end of the impact head.

[0011] As a preferred solution, the lower end of each guide column is inserted into the impact head, and the outer side of the lower end of each guide column is provided with an outwardly protruding stop portion, and the impact head is provided with a sliding groove that matches the stop portion and extends in the up and down directions.

[0012] As a preferred solution, there are multiple tension springs, and each tension spring is respectively sleeved on the outside of each guide column.

[0013] As a preferred solution, the impact hammer is fixedly connected to an infrared emitting device, and the infrared emitting device emits horizontally extending infrared rays in a direction away from the impact hammer; and a vertically arranged infrared sensing screen is provided on the fixing frame.

[0014] As a preferred embodiment, the upper end of the impact hammer is provided with a fixed platform protruding outward, and the rock uniaxial compressive strength measuring device includes a vertically arranged swing arm, the middle part of the swing arm is hinged to the side wall of the mounting plate, and the lower end of the swing arm is provided with a hook extending toward the middle part of the mounting plate. The hook and the mounting plate are arranged at intervals above and below, and the interval between the hook and the swing arm forms a holding space for clamping the fixed platform. Swinging the swing arm can cause the hook to swing outward, so that the fixed platform is disengaged from the holding space.

[0015] As a preferred embodiment, the upper end of the swing arm is provided with a lateral extension portion extending toward the center of the mounting plate and located above the mounting plate, and the rock uniaxial compressive strength measuring device includes a reset spring, the upper end of the reset spring abuts against the lower end of the lateral extension portion, and the lower end of the reset spring abuts against the upper end of the mounting plate.

[0016] As a preferred solution, a hoisting mechanism is provided at the upper end of the support frame, and the hoisting mechanism is provided with a rope body, and the rope body extends vertically downward and is connected to the impact hammer.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The rock uniaxial compressive strength measuring device of the present invention includes a support frame, a clamping mechanism for clamping a rock sample is fixed to the lower part of the support frame, an impact head is connected to the middle part of the support frame, and an impact mechanism for applying impact force to the impact head is connected to the upper part of the support frame. When performing an impact test, the clamping mechanism clamps the rock sample, and there is no need for an operator to provide a reaction force to the measuring device. In addition, the bottom end of the impact head is provided with at least one downwardly protruding arc-shaped rib, and the lower end of the arc-shaped rib is in line contact with the upper end of the rock sample, thereby reducing the influence of the measured position on the measurement result and reducing the discreteness of the measurement data. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a front view of the rock uniaxial compressive strength measuring device of the present invention;

[0020] Figure 2 This is an axonometric diagram of the rock uniaxial compressive strength measuring device of the present invention;

[0021] Figure 3 for Figure 1 Left view of;

[0022] Figure 4 It is a structural diagram of the clamping mechanism;

[0023] Figure 5 This is a schematic diagram of the structure after the first clamping member and the second clamping member are close to each other;

[0024] Figure 6is a cross-sectional view of the impact head;

[0025] In the figure, 1. support frame; 11. mounting plate; 12. guide column; 13. infrared sensor screen; 121. stopper; 122. guide column receiving groove; 2. rock sample; 3. clamping mechanism; 31. transverse guide rail; 32. first clamping member; 33. second clamping member; 34. screw; 4. impact head; 41. arc-shaped rib; 42. slide groove; 51. impact hammer; 52. tension spring; 53. fixed platform; 61. swing arm; 62. hook; 63. transverse extension portion; 7. reset spring; 8. hoisting mechanism; 81. rope body; 9. buffer spring. DETAILED DESCRIPTION

[0026] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0027] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", "top", "bottom", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention 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 limiting the present invention. It should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but such information should not be limited to these terms, which are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information.

[0028] like Figures 1 to 6 As shown, a preferred embodiment of the rock uniaxial compressive strength measuring device of the present invention includes a support frame 1, a clamping mechanism 3 for clamping a rock sample 2 fixed to the lower portion of the support frame 1, an impact head 4 connected to the middle portion of the support frame 1, and an impact mechanism for applying an impact force to the impact head 4 connected to the upper portion of the support frame 1. The bottom end of the impact head 4 is provided with at least one downwardly protruding arcuate rib 41, so that the lower end of the arcuate rib 41 is in line contact with the upper end of the rock sample 2. During the impact test, the clamping mechanism 3 clamps the rock sample 2, eliminating the need for the operator to provide a reaction force to the measuring device. In addition, the bottom end of the impact head 4 is provided with at least one downwardly protruding arcuate rib 41, the lower end of which is in line contact with the upper end of the rock sample 2, thereby reducing the influence of the measured position on the measurement results and reducing the discreteness of the measurement data.

[0029] Among them, such as Figure 4 、 Figure 5As shown, the clamping mechanism 3 includes a transverse guide rail 31 fixed to the lower portion of the support frame. The transverse guide rail 31 is located above the rock sample 2. A first clamping member 32 and a second clamping member 33 are slidably provided on the transverse guide rail 31 and spaced apart from each other. The rock sample 2 is disposed between the first clamping member 32 and the second clamping member 33. The first clamping member 32 and the second clamping member 33 move toward each other to clamp the rock sample 2 or away from each other to release the rock sample 2. There are various ways to drive the first clamping member 32 and the second clamping member 33, such as providing a telescopic air cylinder, a telescopic oil cylinder, or an electric telescopic rod to respectively drive the first clamping member 32 and the second clamping member 33.

[0030] In this embodiment, to ensure a compact clamping mechanism, the clamping mechanism 3 includes a screw 34 arranged parallel to the transverse guide rail 31. The first end of the screw 34 is threadedly connected to the first clamping member 32, and the second end of the screw 34 is threadedly connected to the second clamping member 33. The external threads of the first end of the screw 34 and the external threads of the second end of the screw 34 have opposite rotation directions. Specifically, the first clamping member 32 and the second clamping member 33 are arranged symmetrically about the center of the impact head 4. By rotating the screw 34, the first clamping member 32 and the second clamping member 33 can be moved synchronously toward the center of the impact head 4 to clamp the extended specimen 2.

[0031] In this embodiment, the cross-section of the impact head 4 is U-shaped, and an arc-shaped convex rib 41 is formed at the bottom of the U-shaped impact head. A mounting plate 11 is fixed to the upper part of the support frame 1, and a plurality of guide posts 12 extending vertically downward are fixedly connected to the mounting plate 11. The impact head 4 is connected to the lower end of each guide post 12; the plurality of guide posts 12 are symmetrically distributed on both sides of the impact head 4 to ensure that the impact head 4 applies a uniform force to the extended specimen 2;

[0032] The impact mechanism includes an impact hammer 51 and a tension spring 52 detachably connected to the lower end of the mounting plate 11. The upper end of the impact head 4 is provided with a spring accommodating groove with an upward opening. The lower end of the tension spring 52 is fixedly connected to the bottom wall of the spring accommodating groove. The upper end of the tension spring 52 is fixedly connected to the lower end of the impact hammer 51. The tension spring 52 pulls the impact hammer 51 removed from the mounting plate 11 to move downward so that the lower end of the impact hammer 51 abuts against the upper end of the impact head 4. Specifically, through holes are provided at the upper and lower positions of the impact hammer 51 and each guide column 12, and the upper part of each guide column 12 is respectively inserted into the corresponding through hole. The impact hammer 51 can slide up and down along the axial direction of each guide column 12. Before the impact, the impact hammer 51 is connected to the lower end of the mounting plate 11, and the tension spring 52 is in a stretched state. After the impact hammer 51 is removed from the mounting plate 11, under the action of its own gravity and the tension of the tension spring, the impact hammer 51 moves downward and hits the upper end of the impact head 4, thereby applying a downward impact force to the impact head 4.

[0033] Specifically, such as Figure 6As shown, the lower end of each guide post 12 is inserted into the impact head 4. The outer side of the lower end of each guide post 12 is provided with an outwardly protruding stopper 121. The impact head 4 is provided with a slide 42 that matches the stopper 121 and extends in the vertical direction. When the impact hammer 51 is connected to the mounting plate 11, the lower end of the stopper 121 abuts against the bottom wall of the slide 42, preventing the impact head 4 from moving upward, so that the tension spring 52 is in a stretched state. The upper part of the impact head is provided with a guide post receiving groove 122 for inserting the guide post. The bottom of the guide post receiving groove 122 is provided with a buffer spring 9. The lower end of each buffer spring 9 abuts against the bottom wall of the corresponding guide post receiving groove 122, and the upper end of each buffer spring 9 abuts against the lower end of the corresponding guide post 12.

[0034] In this embodiment, there are a plurality of tension springs 52, each of which is sleeved on the outside of each guide post 12. Each guide post 12 not only guides the impact hammer 51, but also guides each tension spring.

[0035] There are various methods for removably attaching the impact hammer 51 to the mounting plate 11, such as screwing or clamping. In this embodiment, the upper end of the impact hammer 51 is provided with an outwardly protruding fixing platform 53. Specifically, the impact hammer 51 includes multiple Schmidt hammers, each mounted on a corresponding guide column 12. The upper end of each Schmidt hammer is fixedly connected to the fixing platform 53, and the fixing platform 53 can also move downward or upward synchronously with each Schmidt hammer. The rock uniaxial compressive strength measuring device includes a vertically arranged swing arm 61. The middle portion of the swing arm 61 is hinged to the side wall of the mounting plate 11. The lower end of the swing arm 61 is provided with a hook 62 extending toward the middle of the mounting plate 11. The hook 62 is spaced apart from the mounting plate 11. The space between the hook 62 and the swing arm 61 forms a retaining space for retaining the fixing platform 53. Swinging the swing arm 61 can swing the hook 62 outward, thereby disengaging the fixing platform 53 from the retaining space. The arrangement of the swing arm 61 and the hook 62 enables the mounting plate 11 to quickly release the fixing platform 53 , thereby releasing the impact hammer 51 .

[0036] Furthermore, the upper end of the swing arm 61 is provided with a transverse extension 63 extending toward the center of the mounting plate 11 and positioned above the mounting plate. The rock uniaxial compressive strength measuring device includes a return spring 7, the upper end of which abuts the lower end of the transverse extension 63, which in turn abuts the upper end of the mounting plate 11. Pressing downward on the transverse extension 63 causes the hook 62 to swing outward; releasing the transverse extension 63 causes the return spring 7 to move upward, causing the hook 62 to swing inward, thereby connecting the fixing platform 53 to the lower end of the mounting plate 11.

[0037] Furthermore, the rock uniaxial compressive strength measuring device includes a push rod connected to the transverse extension portion 63 , which extends horizontally to the outside of the rock uniaxial compressive strength measuring device. Pressing the push rod downward can achieve pressing of the transverse extension portion 63 .

[0038] In this embodiment, the impact hammer 51 is fixedly connected to an infrared emitting device that emits horizontal infrared rays in a direction away from the impact hammer 51. A vertically arranged infrared sensor screen 13 is provided on the fixing frame 1. Specifically, the infrared sensor screen converts the position information of the infrared signal on the infrared display screen into coordinates, thereby determining the rebound height of the impact hammer 51. The infrared emitting device and the infrared sensor screen do not come into contact during the test, thus avoiding the influence of contact measurement on the rebound height.

[0039] To lift the hammer 51 after it has fallen, in this embodiment, a hoisting mechanism 8 is provided at the upper end of the support frame 1. The hoisting mechanism 8 includes a rope 81 that extends vertically downward and is connected to the hammer 51. Specifically, the hoisting mechanism 8 includes a hoisting wheel fixed to the top of the support frame 1. The upper end of the rope 81 is connected to the outer side of the hoisting wheel. By manually cranking the hoisting wheel, the hammer 51 can be lifted.

[0040] In summary, a preferred embodiment of the rock uniaxial compressive strength measuring device of the present invention includes a support frame 1, a clamping mechanism 3 for clamping a rock sample 2 fixed to the lower portion of the support frame 1, an impact head 4 connected to the middle portion of the support frame 1, and an impact mechanism for applying an impact force to the impact head 4 connected to the upper portion of the support frame 1. The bottom end of the impact head 4 is provided with at least one downwardly protruding arc-shaped rib 41, so that the lower end of the arc-shaped rib 41 is in line contact with the upper end of the rock sample 2. When conducting an impact test, the clamping mechanism 3 clamps the rock sample 2, eliminating the need for an operator to ensure that the lower end of the arc-shaped rib 41 of the measuring device is in line contact with the upper end of the rock sample 2, thereby reducing the influence of the measured position on the measurement results and reducing the discreteness of the measurement data.

[0041] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A rock uniaxial compressive strength measuring device, characterized in that: The invention comprises a support frame (1), a clamping mechanism (3) for clamping a rock sample (2) is fixed at the lower part of the support frame (1), an impact head (4) is connected to the middle part of the support frame (1), an impact mechanism for applying an impact force to the impact head (4) is connected to the upper part of the support frame (1), the bottom end of the impact head (4) is provided with at least one downwardly protruding arc-shaped rib (41), the lower end of the arc-shaped rib (41) is in line contact with the upper end of the rock sample (2); the clamping mechanism (3) comprises a transverse guide rail (31) fixed to the lower part of the support frame ), the transverse guide rail (31) is located above the rock sample (2), a first clamping member (32) and a second clamping member (33) are slidably provided on the transverse guide rail (31) and are arranged in a spaced relationship with each other, the rock sample (2) is arranged between the first clamping member (32) and the second clamping member (33), the first clamping member (32) and the second clamping member (33) are moved closer to each other to clamp the rock sample (2), or the first clamping member (32) and the second clamping member (33) are moved away from each other to release the rock sample (2); A mounting plate (11) is fixed to the upper portion of the support frame (1), a plurality of guide posts (12) extending vertically downward are fixedly connected to the mounting plate (11), and the impact head (4) is connected to the lower end of each guide post (12); The impact mechanism comprises an impact hammer (51) and a tension spring (52) detachably connected to the lower end of the mounting plate (11); the upper end of the impact head (4) is provided with a spring receiving groove with an upward opening; the lower end of the tension spring (52) is fixedly connected to the bottom wall of the spring receiving groove; the upper end of the tension spring (52) is fixedly connected to the lower end of the impact hammer (51); the tension spring (52) pulls the impact hammer (51) removed from the mounting plate (11) to move downward, so that the lower end of the impact hammer (51) abuts against the upper end of the impact head (4); The impact hammer (51) is fixedly connected to an infrared emitting device, and the infrared emitting device emits infrared rays extending horizontally in a direction away from the impact hammer (51); the support frame (1) is provided with a vertically arranged infrared sensing screen (13); The upper end of the impact hammer (51) is provided with a fixing platform (53) protruding outward. The rock uniaxial compressive strength measuring device includes a vertically arranged swing arm (61). The middle part of the swing arm (61) is hinged to the side wall of the mounting plate (11). The lower end of the swing arm (61) is provided with a hook (62) extending toward the middle part of the mounting plate (11). The hook (62) and the mounting plate (11) are arranged with an interval up and down. The interval between the hook (62) and the swing arm (61) forms a holding space for holding the fixing platform (53). Swinging the swing arm (61) can cause the hook (62) to swing outward, so that the fixing platform (53) is separated from the holding space.

2. The rock uniaxial compressive strength measuring device according to claim 1, characterized in that: The clamping mechanism (3) comprises a screw (34) arranged parallel to the transverse guide rail (31), a first end of the screw (34) being screwed to the first clamping member (32), a second end of the screw (34) being screwed to the second clamping member (33), and an external thread at the first end of the screw (34) and an external thread at the second end of the screw (34) having opposite rotation directions.

3. The rock uniaxial compressive strength measuring device according to claim 1, characterized in that: The lower end of each guide post (12) is inserted into the impact head (4), and the outer side of the lower end of each guide post (12) is provided with a stopper (121) protruding outward, and the impact head (4) is provided with a slide groove (42) matching the stopper (121) and extending in the up-down direction.

4. The rock uniaxial compressive strength measuring device according to claim 1, characterized in that: There are a plurality of tension springs (52), and each tension spring (52) is sleeved on the outside of each guide column (12).

5. The rock uniaxial compressive strength measuring device according to claim 1, characterized in that: The upper end of the swing arm (61) is provided with a transverse extension portion (63) extending toward the center of the mounting plate (11) and located above the mounting plate. The rock uniaxial compressive strength measuring device includes a reset spring (7). The upper end of the reset spring (7) abuts against the lower end of the transverse extension portion (63), and the lower end of the reset spring (7) abuts against the upper end of the mounting plate (11).

6. The rock uniaxial compressive strength measuring device according to claim 1, characterized in that: A hoisting mechanism (8) is provided at the upper end of the support frame (1), and the hoisting mechanism (8) is provided with a rope body (81). The rope body (81) extends vertically downward and is connected to the impact hammer (51).

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