Steel strand shear test device

Abstract

The present invention relates to a shear test device for steel strands, which includes a fixed seat, a shear head, and a steel strand fixing structure and a steel strand force applying structure separately arranged on both sides of the shear head. The shear head is arranged on the fixed seat, and the top of the shear head is used to support the steel strand. A first force value sensor is arranged between the shear head and the fixed seat, and the first force value sensor is used to measure the downward pressure received by the shear head; the steel strand fixing structure is used to fix one end of the steel strand, the steel strand force applying structure is used to apply a tensile force to the other end of the steel strand. Both the steel strand fixing structure and the steel strand force applying structure are lower than the top of the shear head, so that the steel strand is supported on the shear head and applies a downward acting force to the shear head after the steel strand is subjected to the tensile action; the steel strand force applying structure includes a second force value sensor, and the second force value sensor measures the tensile force received by the steel strand.

Description

Technical Field

[0001] The present invention belongs to the field of shear test devices, and particularly relates to a shear test device for steel strands. Background Art

[0002] When steel strands (prestressed anchor cables) are applied to engineering scenarios such as coal mine roadways and initial support of tunnels, there is a situation where the cable force of the steel strands is much smaller than the tension value and they rupture. The rupture position is mainly within the range of 1 - 2 m from the hole mouth, and the fracture surface is at 45°, which belongs to obvious shear fracture.

[0003] In order to analyze the fracture mechanism of steel strands, it is necessary to conduct shear fracture tests on steel strands. For example, the utility model patent with the authorization announcement number CN203426521 U discloses a shear device for testing the shear strength of locking steel wires. It includes a tool holder, and the tool holder is provided with a cross - shaped and mutually - communicating cutting groove and a feeding hole. During the test, the shear device is installed on a shear strength testing machine. The steel wire is inserted into the feeding hole, and both ends of the steel wire are located outside the tool holder for fixation; the cutting tool is inserted into the cutting groove and applies force to the steel wire. When the steel wire is cut by the cutting tool, the shear strength of the steel wire is measured by the shear strength testing machine.

[0004] The problem with this patent is that it detects the shear strength of the steel wire by fixing both ends of the steel wire and applying force to the middle position of the steel wire. Most of the reasons for the fracture of steel strands in the prior art are due to the steel strands being sheared by external forces while being tensioned. However, this patent cannot truly simulate the stress situation of the steel strands, and it is impossible to use the shear device of this patent to analyze the fracture mechanism of the steel strands. Summary of the Invention

[0005] The present invention provides a shear test device for steel strands to solve the technical problem that the shear device in the prior art cannot truly simulate the stress situation of the steel strands, resulting in the inability to analyze the fracture mechanism of the steel strands.

[0006] To solve the above problems, the shear test device for steel strands provided by the present invention adopts the following technical solutions: The shear test device for steel strands includes:

[0007] A fixed seat;

[0008] A shear head, which is arranged on the fixed seat. The top of the shear head is used to support the steel strand. A first force value sensor is arranged between the shear head and the fixed seat, and the first force value sensor is used to measure the downward pressure received by the shear head;

[0009] The steel strand fixing structure and the steel strand force applying structure are separately arranged on both sides of the shearing head. The steel strand fixing structure is used to fix one end of the steel strand, and the steel strand force applying structure is used to apply tensile force to the other end of the steel strand. Both the steel strand fixing structure and the steel strand force applying structure are lower than the top of the shearing head, so that the steel strand is supported on the shearing head and applies a downward force to the shearing head after being subjected to the tensile action; the steel strand force applying structure includes a second force value sensor, and the second force value sensor measures the tensile force received by the steel strand.

[0010] The beneficial effects are as follows: One end of the steel strand is fixed on the steel strand fixing structure, and the other end is connected to the steel strand force applying structure. The part between the two ends is supported on the shearing head. Since both the steel strand fixing structure and the steel strand force applying structure are lower than the shearing head, after the steel strand force applying structure works, the overall steel strand presents a state of being high in the middle and low at both ends. After the steel strand is tensioned, it will press down on the shearing head. The first force value sensor can detect the pressing force received by the shearing head, and the magnitude of this part of the pressing force is the same as the shearing force of the shearing head on the steel strand, that is, the first force value sensor can detect the shearing force received by the steel strand; the second force value sensor can detect the tensile force applied by the steel strand force applying structure, record the tensile force and the shearing force at the same time, and can analyze the breaking excitation of the steel strand when the steel strand breaks. In the present invention, the shear test is carried out by tensioning the steel strand and applying force to the shearing head, and this method is more in line with the actual working conditions of the steel strand. The breaking mechanism analyzed by the steel strand shear test device according to the present invention is also more accurate.

[0011] As a further improvement, the steel strand fixing structure includes a fixed end pedestal for fixing the steel strand, and the steel strand force applying structure includes a tension end pedestal;

[0012] Taking the arrangement direction of the steel strand fixing structure, the shearing head, and the steel strand force applying structure as the left-right direction, and the horizontal direction perpendicular to the left-right direction as the front-back direction;

[0013] The fixed end pedestal and the tension end pedestal are rotatably assembled on the fixed seat around a horizontal axis extending in the front-back direction;

[0014] The steel strand force applying structure further includes a tensioning member provided on the tension end pedestal, and the tensioning member is used to apply tensile force to the steel strand. During the process of the tensioning member applying tensile force to the steel strand, the steel strand is automatically tensioned after being pulled. During the tensioning process, the steel strand will push against the fixed end pedestal and the tension end pedestal to rotate around their respective horizontal axes, preventing the steel strand from being bent or the like and affecting the test results.

[0015] As a further improvement, the fixed end pedestal and the tensioning end pedestal are both provided with pedestal through holes for the steel strand to pass through. Among them, the pedestal through hole of the fixed end pedestal is a pedestal tapered hole. The steel strand fixing structure further includes an anchoring clip arranged in the pedestal tapered hole. The anchoring clip is used to clamp the steel strand. When the steel strand is tensioned, it pulls the anchoring clip, and the anchoring clip is clamped by the tightening action of the pedestal tapered hole to clamp the steel strand. The method of combining the anchoring clip and the pedestal tapered hole is used to clamp the steel strand, and the clamping method is simple and the clamping is reliable.

[0016] As a further improvement, pedestal mounting grooves are provided on both the left and right end faces of the fixed seat. The pedestal mounting grooves penetrate the fixed seat in the up and down direction. Pin shaft sliding grooves are provided on the front and rear side walls of the pedestal mounting grooves, and the pin shaft sliding grooves extend to the end faces of the corresponding ends of the fixed seat;

[0017] Fixed pin shafts are symmetrically arranged on the outer sides of the fixed end pedestal and the tensioning end pedestal. The fixed pin shafts are slidably assembled in the pin shaft sliding grooves. The pin shaft sliding grooves have top surfaces that are in blocking cooperation with the fixed pin shafts to prevent the fixed pin shafts from slipping out of the pin shaft sliding grooves upward. The central axis of the fixed pin shafts is the horizontal axis, and the fixed end pedestal and the tensioning end pedestal can both rotate around the central axis of the fixed pin shafts. The fixed pin shafts not only serve as the rotation axes of the fixed end pedestal and the tensioning end pedestal, but also can be in blocking cooperation with the pin shaft sliding grooves to prevent the fixed end pedestal and the tensioning end pedestal from moving in the extending direction of the steel strand, and the functions are more concentrated.

[0018] As a further improvement, safety pin holes extending up and down are provided at both ends of the fixed seat. The safety pin holes communicate with the pin shaft sliding grooves; the safety pin holes are for safety pins to be inserted, and the safety pins are used to be in blocking cooperation with the fixed pin shafts to prevent the fixed pin shafts from sliding out of the pin shaft sliding grooves in the horizontal direction.

[0019] As a further improvement, the second force value sensor is fixedly arranged on the side of the tensioning end pedestal facing away from the shear head. The tensioning component includes a hole-through jack fixedly arranged on the second force value sensor, and a force application seat is arranged on the telescopic end of the hole-through jack;

[0020] The second force value sensor is a ring-shaped sensor for the steel strand to pass through; a conical hole of the force application seat is provided on the force application seat, and the steel strand force application structure further includes an anchor clip arranged in the conical hole of the force application seat. The anchor clip is used to clamp the steel strand. After the through-hole jack is started, it pushes the force application seat, and the anchor clip is tightened by the conical hole of the force application seat to clamp and tension the steel strand. When the second force value sensor is in use, it is subjected to the jacking pressure of the through-hole jack, and this jacking pressure is equal to the tensile force applied by the through-hole jack to the steel strand. The tensile force received by the steel strand can be detected through the second force value sensor; the second force value sensor, the through-hole jack, and the force application seat are arranged and installed in sequence. The tensioning end pedestal, the second force value sensor, the through-hole jack, and the force application seat are integrated into a unit that is rotatably installed on the fixed seat, which is convenient for installation and disassembly. The steel strand is clamped and fixed through the conical hole of the force application seat and the anchor clip, and the clamping method is simple and reliable.

[0021] As a further improvement, bolt through-holes are provided on both the fixed seat and the shear head. The bolt through-holes of the fixed seat and the shear head are both oblong holes. The oblong hole of one of the fixed seat and the shear head extends in the left-right direction, and the oblong hole of the other of the fixed seat and the shear head extends in the front-back direction; the steel strand shear test device further includes a bolt passing through the bolt through-holes. The oblong hole extending in the left-right direction can adjust the position of the shear head in the left-right direction, that is, adjust the distance between the shear head and the fixed end pedestal and the tensioning end pedestal; the oblong hole extending in the front-back direction can adjust the position of the shear head in the front-back direction; by adjusting the horizontal position of the shear head, the use scenarios of different working conditions can be simulated, making the test more in line with the actual working conditions.

[0022] As a further improvement, a first nut, a second nut, and a third nut are arranged on the bolt in sequence from top to bottom. The rod part of the bolt passes through from top to bottom. The first nut is located below the shear head, the second nut is located above the fixed seat, and the third nut is located below the bolt through-hole in the fixed seat. The second nut and the third nut clamp and fix the fixed seat up and down. The second nut and the third nut clamp and fix the fixed seat up and down, and the overall height of the shear head can be changed by changing the heights of the second nut and the third nut.

[0023] As a further improvement, the top of the shear head is a pointed top with a circular chamfer.

[0024] As a further improvement, the shear head includes a base part and a replaceable part that can be detachably installed above the base part, and the circular chamfer is provided on the replaceable part. During use, different replaceable parts can be replaced according to needs. The differences between different replaceable parts mainly lie in the size of the circular chamfer, which can be replaced at any time according to needs. Description of the Drawings

[0025] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features, and advantages of the exemplary embodiments of the present invention will become readily understood. In the drawings, several embodiments of the present invention are shown in an exemplary rather than restrictive manner, and the same or corresponding reference numerals denote the same or corresponding parts, wherein:

[0026] Figure 1 Schematic diagram when Example 1 of the steel strand shear test device is in use;

[0027] Figure 2 Front view of the fixed seat;

[0028] Figure 3 Top view of the fixed seat;

[0029] Figure 4 Left view of the fixed seat;

[0030] Figure 5 Front view of the shear head;

[0031] Figure 6 Top view of the shear head;

[0032] Figure 7 Structural schematic diagram of the fixed end pedestal;

[0033] Figure 8 Structural schematic diagram of the tension end pedestal;

[0034] Figure 9 Schematic diagram of the force application structure (the tension end pedestal is not shown);

[0035] Figure 10 Top view of the shear head in Example 2 of the steel strand shear test device;

[0036] Figure 11 Front view of the shear head in Example 3 of the steel strand shear test device;

[0037] Figure 12 Structural schematic diagram of the replaceable part of the shear head in Example 3 of the steel strand shear test device.

[0038] Explanation of reference numerals:

[0039] 1. Fixing seat; 11. Fixing seat body; 12. Fixing ear plate; 13. First oblong hole; 14. Base mounting groove; 15. Pin slideway; 16. Safety pin hole; 2. Shearing head; 21. Shearing head body; 22. Circular chamfer; 23. Connecting ear plate; 24. Second oblong hole; 25. Bolt; 26. First nut; 27. Second nut; 28. Third nut; 29. ​​Base part; 210. Replaceable Part; 211, slot; 3, steel strand fixing structure; 31, fixed end pedestal; 32, pedestal conical hole; 33, fixed pin; 4, steel strand force structure; 41, tensioning end pedestal; 42, second force sensor; 43, through-type jack; 44, force seat; 45, first flange; 46, second flange; 47, force seat conical hole; 5, first force sensor; 6, steel strand; 7, anchor clip. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Those skilled in the art should know that the embodiments described below are part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0041] The principle and spirit of the present invention are explained in detail below with reference to several representative embodiments of the present invention.

[0042] Embodiment 1 of the steel strand shear test device provided by the present invention:

[0043] like Figures 1 to 9 As shown, the steel strand shear test device (hereinafter referred to as the test device) mainly includes a fixed seat 1, a shear head 2, a steel strand fixing structure 3, a steel strand force structure 4, and a first force sensor 5. The shear head 2, the steel strand fixing structure 3, and the steel strand force structure 4 are all installed on the fixed seat 1.

[0044] like Figure 2 , Figure 3 and Figure 4 As shown, the fixing seat 1 includes a rectangular fixing seat body 11, and fixing ear plates 12 are integrally formed on the front and rear sides of the top of the fixing seat body 11. The fixing ear plates 12 extend left and right, and a first oblong hole 13 is opened on each fixing ear plate 12. The first oblong hole 13 passes through the fixing ear plate 12 from top to bottom, and the first oblong hole 13 extends in the left and right direction. A plurality of first oblong holes 13 (four in this embodiment) are opened on each fixing ear plate 12, and the plurality of first oblong holes 13 are arranged at intervals in the left and right direction. The first oblong holes 13 on the two fixing ear plates 12 correspond to each other in the front and rear direction.

[0045] At the left and right ends of the fixed seat main body 11, pedestal mounting grooves 14 are respectively formed. The pedestal mounting grooves 14 penetrate through the fixed seat main body 11 vertically. The bottom of the pedestal mounting groove 14 is arranged obliquely. Specifically, the bottom of the pedestal mounting groove 14 is inclined upward and towards the middle position of the fixed seat main body 11. The obliquely arranged bottom can avoid the fixed-end pedestal 31 and the tensioning-end pedestal 41. The bottom of the pedestal mounting groove 14 is an arc bottom.

[0046] Pin shaft sliding grooves 15 are respectively formed on the two groove walls of the pedestal mounting groove 14. The pin shaft sliding grooves 15 extend horizontally. The pin shaft sliding grooves 15 are structures closed at the top and bottom. The pin shaft sliding grooves 15 extend to the left and right end faces of the fixed seat main body 11. The top surface of the pin shaft sliding groove 15 is used to block against the fixed pin shaft 33 to prevent the fixed pin shaft 33 from slipping out upward. A safety pin hole 16 penetrating through the fixed seat main body 11 vertically is formed on the fixed seat main body 11. The safety pin hole 16 communicates with the pin shaft sliding groove 15. The safety pin hole 16 is located at positions of the fixed seat main body 11 close to the left and right ends.

[0047] The structure of the shearing head 2 is as Figure 5 , Figure 6 shown. The shearing head 2 includes a shearing head main body 21. The shearing head main body 21 is in a conical shape that is narrow at the top and wide at the bottom. The top of the shearing head main body 21 is used to support the steel strand 6 upward. The top of the shearing head main body 21 has a circular chamfer 22. At the front and rear sides of the bottom of the shearing head main body 21, connecting ear plates 23 are integrally formed respectively. Two second long circular holes 24 are respectively formed on each connecting ear plate 23. The second long circular holes 24 penetrate through the connecting ear plates 23 vertically. The second long circular holes 24 extend in the front-rear direction. The two second long circular holes 24 on the same connecting ear plate 23 are arranged at intervals in the front-rear direction. The second long circular holes 24 on the two connecting ear plates 23 correspond one by one.

[0048] Bolts 25 are respectively installed in each second long circular hole 24. The bolts 25 penetrate through the second long circular holes 24 from top to bottom. The heads of the bolts 25 are located above the connecting ear plates 23. On the rod parts of the bolts 25, first nuts 26, second nuts 27, and third nuts 28 are installed in sequence from top to bottom.

[0049] As Figure 7 shown, the steel strand fixing structure 3 includes a fixed-end pedestal 31. The fixed-end pedestal 31 is in an overall frustum structure. A pedestal through hole is formed in the fixed-end pedestal 31. The pedestal through hole in the fixed-end pedestal 31 is a pedestal tapered hole 32. At positions close to the middle on the outer side of the fixed-end pedestal 31, two fixed pin shafts 33 are symmetrically arranged. Preferably, the outer diameter of the fixed pin shaft 33 is the same as the height dimension of the pin shaft sliding groove 15 in the up-down direction. Of course, the outer diameter of the fixed pin shaft 33 can also be slightly smaller than the height dimension of the pin shaft sliding groove 15 in the up-down direction. The fixed-end pedestal 31 can rotate around the axis of the fixed pin shaft 33.

[0050] As Figure 8 , Figure 9 shown, the strand force application structure 4 includes a tension end pedestal 41, a second force value sensor 42, a hole-through jack 43, and a force application seat 44. The structure of the tension end pedestal 41 is similar to that of the fixed end pedestal 31. The difference is that a first flange 45 is provided at the end with a larger outer diameter on the tension end pedestal 41. The second force value sensor 42 here is an annular pressure sensor, and the strand 6 can pass through the second force value sensor 42. Among them, the annular pressure sensor is a prior art and will not be elaborated here. For example, it can adopt the method of the Chinese utility model patent with the authorized announcement number CN203310558U. One end of the second force value sensor 42 is fixedly installed with a second flange 46, and the second flange 46 is connected to the first flange 45 through bolts.

[0051] The hole-through jack 43 and the force application seat 44 together form a tensioning component. One end of the hole-through jack 43 is fixed on the second force value sensor 42, and the strand 7 passes through the hole-through jack 43. The force application seat 44 is fixed at the other end of the hole-through jack 43. A force application seat tapered hole 47 is provided in the force application seat 44. The force application seat tapered hole 47 penetrates through the force application seat 44, and the force application seat tapered hole 47 is for the strand 7 to pass through. The inner diameter of one end of the force application seat tapered hole 47 close to the hole-through jack 43 is larger than that of the other end.

[0052] Assembly process: First, install the fixed end pedestal 31 and the tension end pedestal 41 on the fixed seat 1. Specifically, slide the fixed pin shafts 33 on the fixed end pedestal 31 and the tension end pedestal 41 into the pin shaft slideways 15. After the fixed pin shafts 33 slide into the pin shaft slideways 15, insert the safety pins into the safety pin holes 16 to prevent the fixed pin shafts 33 from sliding out of the pin shaft slideways 15.

[0053] Then, the shearing head 2 is installed on the fixing seat 1. Specifically, the first nut 26 and the second nut 27 are first installed on the bolt 25, the second oblong hole 24 of the connecting ear plate 23 on the shearing head 2 is aligned with the first oblong hole 13 of the fixing ear plate 12 on the fixing seat 1, and the bolt 25 is inserted into the first oblong hole 13, and then the third nut 28 is installed. The bolt 25 is fixed to the fixing ear plate 12 by the second nut 27 and the third nut 28. By adjusting the positions of the second nut 27 and the third nut 28 on the bolt 25, the height of the shearing head 2 can be adjusted. By installing the shearing head 2 on different first oblong holes 13, the position of the shearing head 2 in the left-right direction can be changed, that is, the distance between the shearing head 2 and the fixing end pedestal 31 and the tensioning end pedestal 41 can be adjusted, and the left-right position of the shearing head 2 can be fine-tuned by changing the position of the bolt 25 in the first oblong hole 13. The front-back position of the shearing head 2 can be fine-tuned by changing the position of the bolt 25 in the second oblong hole 24. By adjusting the height and horizontal position of the shear head 2, usage scenarios of different working conditions can be simulated, making the test more in line with actual working conditions.

[0054] During installation, the first force sensor 5 is placed between the fixed seat 1 and the shearing head 2. After placement, there is space between the shearing head 2 and the first nut 26. The shearing head 2 can move downward as a whole after receiving a downward force, pressing the first force sensor 5, thereby detecting the pressure on the shearing head 2. After the shearing head 2 is installed, the height of the circular chamfer 22 is higher than the fixed end seat 31 and the tension end seat 41.

[0055] Afterwards, an anchor clip 7 is externally mounted on the first end of the steel strand 6 (the two ends of the steel strand 6 are defined as the first end and the second end, respectively, the first end corresponds to the fixed end pedestal 31, and the second end corresponds to the force-applying seat 44) (the structure of the anchor clip 7 is the prior art, and the anchor clip 7 specifically includes two matching fan rings, and the steel strand 6 passes through the middle of the two fan rings. The two fan rings can clamp the steel strand 6 after the walls of the conical hole 32 of the pedestal and the conical hole 47 of the force-applying seat are tightened). The second end of the steel strand 6 is inserted into the end with a larger hole diameter in the conical hole 32 of the pedestal, and the anchor clip 7 on the first end is inserted into the conical hole 32 of the pedestal; the second end of the steel strand 6 is passed around the shear head 2 and then sequentially passed through the tensioning end pedestal 41, the second force sensor 42, the through-type jack 43 and the force seat 44, and the anchor clip 7 is placed in the force seat 44, so that the second end of the steel strand 6 is inserted into the anchor clip 7 in the force seat 44.

[0056] During the inspection, the through-type jack 43 is turned on, and the through-type jack 43 pushes the force-applying seat 44, and the force-applying seat 44 moves and clamps the second end of the steel strand 6 through the anchoring clip 7, and then the force-applying seat 44 applies tensioning force to the steel strand 6; the first end of the steel strand 6 is fixed to the fixed end seat 31 through the tensioning anchoring clip 7. Since the shearing head 2 is located between the fixed end seat 31 and the tensioning end seat 41, and the shearing head 2 is higher than the fixed end seat 31 and the tensioning end seat 41, in the process of the steel strand 6 being gradually tensioned, the steel strand 6 applies a force to the fixed end seat 31 and the tensioning end seat 41 to make the two move closer to each other, and the fixed end seat 31 and the tensioning end seat 41 move along the pin shaft slideway 15 and approach each other until the fixed pin shaft 33 slides to the end of the pin shaft slideway 15. At the same time, under the tensioning action of the steel strand 6, the steel strand 6 rotates around its respective fixed pin shafts 33 against the fixed end pedestal 31 and the tensioning end pedestal 41, wherein the upper ends of the fixed end pedestal 31 and the tensioning end pedestal 41 rotate toward the shear head 2 to avoid contact between the steel strand 6 and the hole openings of the pedestals in the fixed end pedestal 31 and the tensioning end pedestal 41. The benefits of the rotation are: on the one hand, it avoids wear on the steel strand 6, and on the other hand, it improves the accuracy of the test results.

[0057] When the steel strand 6 is tensioned, it will press down the shear head 2, and the first force sensor 5 will be pressed to measure the force; the shear head 2 applies shear force to the steel strand 6, and the force value measured by the first force sensor 5 is the shear force applied by the shear head 2 to the steel strand 6. The through-type jack 43 presses on the second force sensor 42, and the force value measured by the second force sensor 42 is the tension force value of the steel strand 6. The tension force is continuously increased until the steel strand 6 breaks, and by simultaneously collecting the shear force and tension force values, the corresponding relationship between the tension force value and the shear force value when the steel strand 6 breaks can be obtained.

[0058] In the present invention, the fixed shear head 2 and the way of applying force to the steel strand 6 are more in line with the actual stress condition of the steel strand 6, and the obtained results are more in line with reality, which is also more helpful for the study of the rupture mechanism of the steel strand 6. The fixed end stand 31 and the tensioning end stand 41 can both rotate to ensure that the steel strand is tight and not bent, and can adapt to shear heads of different heights and different horizontal positions, ensuring the accuracy of the test and the results.

[0059] Embodiment 2 of the steel strand shear test device provided by the present invention:

[0060] The difference from Example 1 is that in Example 1, the second oblong hole on the connecting ear plate extends in the front-to-back direction, and the first oblong hole on the fixing ear plate extends in the left-to-right direction. Figure 10 As shown, the second oblong hole 24 on the connecting ear plate 23 extends in the left-right direction.

[0061] Example 3 of the shear resistance test device for steel strands provided by the present invention:

[0062] The difference from Example 1 is that in Example 1, the shear head body is an integral structure. In this embodiment, as shown in Figure 11 and Figure 12 , the shear head body 21 includes a base part 29 and a replaceable part 210 detachably installed above the base part 29. Among them, the circular chamfer 22 is provided on the replaceable part 210. Specifically, the base part 29 is a frustum structure with a gradually increasing width from top to bottom; a T-shaped groove penetrating through the front and back is provided at the top of the base part 29. The bottom of the replaceable part 210 is a T-shaped structure, and the top is a conical structure with a gradually increasing width from top to bottom, and a circular chamfer 22 is provided at its top. A clamping groove 211 is formed on the outer side of the replaceable part 210. During assembly, the bottom of the replaceable part 210 is adaptively clamped into the T-shaped groove at the top of the base part 29 to complete the detachable assembly between the replaceable part 210 and the base part 29.

[0063] During use, different replaceable parts 210 can be replaced according to needs. The difference between different replaceable parts 210 mainly lies in the size of the circular chamfer 22. For example, the diameter of the circular chamfer 22 of one replaceable part 210 is 10 mm, and the diameter of the circular chamfer 22 of another replaceable part 210 is 20 mm, etc.

[0064] In other embodiments, in order to achieve the detachable connection between the base part 29 and the replaceable part 210, the following method can also be adopted: the top surface of the base part 29 and the bottom surface of the replaceable part 210 are both flat. Threaded holes are provided at the top of the base part 29, and counterbored holes penetrating through the top and bottom are provided on the replaceable part 210. The counterbored holes and the threaded holes correspond one by one, and bolts penetrate through the counterbored holes and are screwed into the threaded holes to achieve the detachable connection between the base part 29 and the replaceable part 210.

[0065] Example 4 of the shear resistance test device for steel strands provided by the present invention:

[0066] The difference from Example 1 is that in Example 1, a first nut, a second nut, and a third nut are provided on the bolt, and the height of the shear head can be adjusted by changing the positions of the second nut and the third nut. In this embodiment, only one nut is provided on the bolt, and the nut is located below the bolt through hole in the fixed seat. At this time, the height of the shear head cannot be adjusted.

[0067] Example 5 of the shear resistance test device for steel strands provided by the present invention:

[0068] The difference from Embodiment 1 is that in Embodiment 1, the steel strand force application structure includes a tensioning component, and the tensioning component includes a through-hole jack and a force application seat. The steel strand is tensioned by the through-hole jack and the force application seat, and the second force value sensor detects the tension force. In this embodiment, the tensioning component may include two telescopic members installed on the second force value sensor. A fixing plate is fixedly installed on the telescopic ends of the two telescopic members together. The steel strand passes through between the two telescopic members and is welded to the fixing plate. Among them, the telescopic member may be a structure such as an oil cylinder or a push rod.

[0069] Embodiment 6 of the steel strand shear resistance test device provided by the present invention:

[0070] The difference from Embodiment 1 is that in Embodiment 1, the steel strand force application structure includes a tensioning component, and the second force value sensor is arranged between the tensioning component and the tensioning end pedestal. In this embodiment, the tensioning component is directly installed on the tensioning end pedestal. The tensioning component includes a through-hole jack and a force application seat. The force application seat and the through-hole jack are not directly connected. The through-hole jack only pushes the force application seat. The second force value sensor is arranged between the through-hole jack and the force application seat to detect the tension force.

[0071] Embodiment 7 of the steel strand shear resistance test device provided by the present invention:

[0072] The difference from Embodiment 1 is that a pedestal mounting seat and a pin shaft slideway are provided on the end face of the fixed seat. Fixed pins are provided on the pedestal (including the fixed end pedestal and the tensioning end pedestal), and the fixed pins slide into the pin shaft slideway, and the pedestal can rotate around the fixed pins. In this embodiment, a circular pin hole is opened on the fixed seat, and fixed pins are provided on the pedestal, and the fixed pins penetrate into the circular pin hole, so that the pedestal can rotate around the central axis of the fixed pins.

[0073] Embodiment 8 of the steel strand shear resistance test device provided by the present invention:

[0074] The difference from Embodiment 1 is that pedestal through-holes for the steel strand to pass through are provided in both the fixed end pedestal and the tensioning end pedestal. The pedestal through-hole of the fixed end pedestal is a tapered hole, and the steel strand is tensioned by cooperating with the anchoring clip. In this embodiment, one end of the steel strand is directly welded to the fixed end pedestal.

[0075] Embodiment 9 of the steel strand shear resistance test device provided by the present invention:

[0076] The difference from Embodiment 1 is that both the fixed end pedestal and the tensioning end pedestal are rotatably installed on the fixed seat. In this embodiment, both the fixed end pedestal and the tensioning end pedestal are fixedly installed on the fixed seat; at this time, in order to avoid the orifice of the pedestal through-hole in the fixed end pedestal and the tensioning end pedestal from wearing the steel strand, the orifice can be designed as a flared structure.

[0077] In addition, in the description of this specification, the meaning of "a plurality of" is at least two, such as two, three or more, etc., unless otherwise specifically defined.

Claims

1. Steel strand shear test device, characterized in that: include: Fixed seat (1); A shearing head (2) is arranged on a fixed seat (1), the top of the shearing head (2) is used to support the steel strand (6), a first force sensor (5) is arranged between the shearing head (2) and the fixed seat (1), and the first force sensor (5) is used to measure the downward pressure exerted on the shearing head (2); A steel strand fixing structure (3) and a steel strand force applying structure (4) are disposed on both sides of the shear head (2), the steel strand fixing structure (3) being used to fix one end of the steel strand (6), and the steel strand force applying structure (4) being used to apply a tensioning force to the other end of the steel strand (6), the steel strand fixing structure (3) and the steel strand force applying structure (4) being both lower than the top of the shear head (2), so that the steel strand (6) is supported on the shear head (2) and applies a downward force to the shear head (2) after the steel strand (6) is subjected to tensioning; the steel strand force applying structure (4) comprises a second force sensor (42), and the second force sensor (42) measures the tensioning force applied to the steel strand (6); the steel strand fixing structure (3) comprises a fixed end pedestal (31), the fixed end pedestal (31) being used to fix the steel strand (6), and the steel strand force applying structure (4) comprises a tensioning end pedestal (41); The arrangement direction of the steel strand fixing structure (3), the shearing head (2), and the steel strand force applying structure (4) is the left-right direction, and the horizontal direction perpendicular to the left-right direction is the front-back direction; The fixed end pedestal (31) and the tension end pedestal (41) are both rotatably mounted on the fixed pedestal (1) around a horizontal axis extending forward and backward; The steel strand force-applying structure (4) also includes a tensioning component disposed on the tensioning end pedestal (41), and the tensioning component is used to apply tensioning force to the steel strand (6).

2. The steel strand shear test device according to claim 1, characterized in that: The fixed end pedestal (31) and the tensioning end pedestal (41) are both provided with pedestal through-holes for the steel strand (6) to pass through, wherein the pedestal through-hole of the fixed end pedestal (31) is a pedestal conical hole (32), and the steel strand fixing structure (3) further comprises an anchoring clip (7) arranged in the pedestal conical hole (32), the anchoring clip (7) being used to clamp the steel strand (6), and when the steel strand (6) is tensioned, the anchoring clip (7) is pulled, and the anchoring clip (7) is tightened by the pedestal conical hole (32) to clamp the steel strand (6).

3. The steel strand shear test device according to claim 1, characterized in that: The left and right end surfaces of the fixed seat (1) are both provided with a seat mounting groove (14), the seat mounting groove (14) penetrates the fixed seat (1) in the up-down direction, and the front and rear side groove walls of the seat mounting groove (14) are both provided with a pin shaft slideway (15), and the pin shaft slideway (15) extends to the end surface of the corresponding end of the fixed seat (1); The fixed end pedestal (31) and the tensioning end pedestal (41) are symmetrically provided with fixed pins (33) on their outer sides. The fixed pins (33) are slidably assembled in the pin slideway (15). The pin slideway (15) has a top surface that cooperates with the fixed pin (33) to prevent the fixed pin (33) from escaping upward from the pin slideway (15). The central axis of the fixed pin (33) is the horizontal axis. The fixed end pedestal (31) and the tensioning end pedestal (41) can both rotate around the central axis of the fixed pin (33).

4. The steel strand shear test device according to claim 3, characterized in that: The two ends of the fixing seat (1) are provided with safety pin holes (16) extending up and down, and the safety pin holes (16) are communicated with the pin shaft slideway (15); the safety pin holes (16) are for inserting the safety pin, and the safety pin is used to cooperate with the fixing pin shaft (33) to prevent the fixing pin shaft (33) from sliding out of the pin shaft slideway (15) in the horizontal direction.

5. The steel strand shear test device according to any one of claims 1 to 4, characterized in that: The second force sensor (42) is fixedly mounted on a side of the tensioning end pedestal (41) facing away from the shearing head (2), and the tensioning component comprises a through-type jack (43) fixedly mounted on the second force sensor (42), and a force application seat (44) is provided on the telescopic end of the through-type jack (43); The second force sensor (42) is an annular sensor for the steel strand (6) to pass through; the force seat (44) is provided with a force seat conical hole (47); the steel strand force-applying structure (4) also includes an anchoring clip (7) arranged in the force seat conical hole (47); the anchoring clip (7) is used to clamp the steel strand (6); after the through-type jack (43) is started, it pushes the force seat (44); the anchoring clip (7) is tightened by the force seat conical hole (47) to clamp the steel strand (6) and tension the steel strand (6).

6. The steel strand shear test device according to any one of claims 1 to 4, characterized in that: The fixing seat (1) and the shearing head (2) are both provided with bolt through holes, and the bolt through holes of the fixing seat (1) and the shearing head (2) are both oblong holes, and the oblong hole of one of the fixing seat (1) and the shearing head (2) extends in the left-right direction, and the oblong hole of the other of the fixing seat (1) and the shearing head (2) extends in the front-back direction; the steel strand shear test device also includes bolts (25) penetrating the bolt through holes.

7. The steel strand shear test device according to claim 6, characterized in that: A first nut (26), a second nut (27), and a third nut (28) are arranged on the bolt (25) in order from top to bottom. The rod of the bolt (25) penetrates from top to bottom. The first nut (26) is located below the shearing head (2), the second nut (27) is located above the fixing seat (1), and the third nut (28) is located below the bolt through hole in the fixing seat (1). The second nut (27) and the third nut (28) clamp the fixing seat (1) up and down.

8. The steel strand shear test device according to any one of claims 1 to 4, characterized in that: The top of the shearing head (2) is a pointed top, and the pointed top has a rounded chamfer (22).

9. The steel strand shear test device according to claim 8, characterized in that: The shearing head (2) comprises a base part (29) and a replaceable part (210) detachably mounted above the base part (29), and the circular chamfer (22) is arranged on the replaceable part (210).

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