Embedded steel bar drawing instrument

Abstract

The utility model relates to the technical field of engineering detection equipment, in particular to an embedded steel bar drawing instrument which comprises a lower base, an upper base, fixing bolts and a drawing instrument body, the lower base is a rectangular plate with the top face being a concave arc face, and a communicating hole allowing a steel bar to be detected to be inserted and communicating the concave arc face with the bottom face is formed in the lower base; a communication hole is formed in the lower base, a sliding groove with a T-shaped section is formed in the lower base and spaced from the communication hole, the length direction of the sliding groove is parallel to the length direction of the communication hole, the upper base is a rectangular plate with the bottom face being a convex arc face, the convex arc face of the upper base is matched with the concave arc face of the lower base, and a sliding block matched with the sliding groove is fixedly connected to the convex arc face of the upper base. The middle of the top face of the upper base is provided with a through hole allowing a to-be-detected steel bar to be inserted therein, the through hole communicates with the top face and the bottom face of the upper base, the inner diameter of the through hole is equal to the width of the communicating hole, the fixing bolt penetrates through the end face of the lower base and is detachably connected with the sliding block, and the drawing instrument body is fixedly connected to the middle of the upper base.

Description

Technical Field

[0001] This application relates to the field of engineering testing equipment technology, and in particular to a pre-embedded rebar pull-out instrument. Background Technology

[0002] Currently, to ensure the construction quality in tunnel, coal mine, foundation pit, or slope reinforcement projects, a certain length of steel bars is pre-embedded during construction for pull-out tests. The anchorage force of the steel bars embedded in the concrete is tested using a pull-out instrument to assess the construction quality.

[0003] The existing rebar pull-out device consists of a manual pump, a pressure gauge, a fixing component, and a hydraulic cylinder. When in use, the hydraulic cylinder and the fixing component are fitted onto the pre-embedded rebar. The bottom end of the hydraulic cylinder abuts against the concrete wall, and the top end is fixed to the hydraulic cylinder by the fixing component. Pressing the manual pump causes the hydraulic cylinder to extend and pull the rebar. The rebar tension value is read by the pressure gauge.

[0004] The existing technical solutions mentioned above have the following defects: the hydraulic cylinder is cylindrical or cuboid. When there is an angle between the steel bar and the concrete surface, after the hydraulic cylinder is sleeved on the steel bar, the bottom end of the hydraulic cylinder cannot be completely in contact with the concrete surface, resulting in a state where one side is in contact and the other side is suspended. During the process of pulling the steel bar, the pulling device may be damaged due to uneven force on the hydraulic cylinder. Utility Model Content

[0005] This application provides a pre-embedded rebar pull-out instrument for detecting the pull-out force of pre-embedded rebar.

[0006] The above-mentioned technical objective of this application is achieved through the following technical solution:

[0007] A pre-embedded rebar pull-out instrument includes a lower base, an upper base, fixing bolts, and a pull-out instrument body. The lower base is a rectangular plate with a concave arc surface on the top surface. The lower base has a connecting hole for inserting the rebar to be tested and connecting the concave arc surface and the bottom surface. A sliding groove with a T-shaped cross section is provided on the lower base and spaced apart from the connecting hole. The length direction of the sliding groove is parallel to the length direction of the connecting hole.

[0008] The upper base is a rectangular plate with a convex arc surface on the bottom. The convex arc surface of the upper base is adapted to the concave arc surface of the lower base. A sliding block adapted to the sliding groove is fixedly connected to the convex arc surface of the upper base, and the sliding block is slidably inserted into the sliding groove. A through hole for inserting the reinforcing bar to be tested is opened in the middle of the top surface of the upper base. The through hole connects the top surface and the bottom surface of the upper base. The inner diameter of the through hole is equal to the width of the connecting hole. The fixing bolt passes through the end face of the lower base and is detachably connected to the sliding block. The pull-out instrument body is fixedly connected to the middle of the upper base.

[0009] By adopting the above technical solution, when measuring the reinforcing bars that form an angle with the concrete surface, the upper base is pushed to tilt on the lower base, and the tilt angle between the upper and lower bases is equal to the angle between the reinforcing bar and the concrete surface. The upper base is fixed with fixing bolts to keep the tilt angle of the upper base constant. The measuring instrument is then placed on the reinforcing bar through the connecting hole, through hole, and hollow hydraulic cylinder in sequence, so that the bottom surface of the lower base is in contact with the concrete surface. Then, the reinforcing bar is fixed by the pull-out instrument body for pull-out testing. During pull-out, the bottom end of the hollow hydraulic cylinder applies force to the upper base, so that the bottom end of the hollow hydraulic cylinder is subjected to uniform force, which helps to protect the pull-out instrument.

[0010] Optionally, a fixing groove communicating with the sliding groove is provided on the end face of the lower base. The fixing groove is arc-shaped and has the same curvature as the concave arc surface of the lower base. The fixing bolt passes through the fixing groove.

[0011] By adopting the above technical solution, the fixing bolt is passed through the fixing groove and abuts against the sliding block, thereby fixing the upper base, which facilitates the insertion of the fixing bolt and fixing the upper base.

[0012] Optionally, the sliding block has multiple threaded holes on its sidewall. These multiple threaded holes are spaced apart along the length of the sidewall of the sliding block away from the connecting hole and are adapted to the fixing bolts.

[0013] By adopting the above technical solution and adjusting the inclination of the upper and lower bases, the number of threaded holes in the sliding groove of the sliding block is increased, which facilitates fixing with fixing bolts.

[0014] Optionally, the connecting hole is formed on the concave arc surface in the middle of the lower base along the width direction of the lower base, the length of the connecting hole is less than the width of the lower base, and both ends of the connecting hole are closed ends.

[0015] By adopting the above technical solution, the two ends of the connecting hole are closed, and the reinforcing bars inserted in the connecting hole are limited, so that the upper base and the lower base will not detach from the reinforcing bars.

[0016] Optionally, the length of the sliding groove is equal to the width of the lower base, and the two ends of the sliding groove are open.

[0017] By adopting the above technical solution, the stroke of the sliding block in the sliding groove is increased, which is beneficial to increasing the tilt angle that the upper and lower bases can adjust.

[0018] Optionally, the body of the pull-out instrument includes a hollow hydraulic cylinder, wherein the inner diameter of the hollow hydraulic cylinder away from the end of the upper base is larger than the inner diameter of the through hole, and the hollow hydraulic cylinder is fixedly connected to the upper base and coaxially arranged with the through hole.

[0019] By adopting the above technical solution, the upper base and the lower base are sleeved on the steel bar, and the steel bar is passed through the through hole. Since the inner diameter of the pipe of the hollow hydraulic cylinder is larger than the inner diameter of the through hole, it is convenient to insert the steel bar into the hollow hydraulic cylinder.

[0020] Optionally, the pull-out device body also includes a fixing component inserted into the central control hydraulic cylinder. The fixing component includes a fixing sleeve and a locking sleeve. The outer walls of the fixing sleeve and the locking sleeve are provided with an outer edge, and the inner wall of the fixing sleeve gradually thickens from the top end to the bottom end and forms an inclined surface.

[0021] By adopting the above technical solution, the fixing sleeve is fitted onto the reinforcing bar and inserted into the hollow hydraulic cylinder. The locking sleeve holds the reinforcing bar tightly and is inserted into the fixing sleeve. The fixing sleeve holds the locking sleeve tightly onto the reinforcing bar and limits the movement through the outer edge. This prevents the fixing sleeve and locking sleeve from being pulled into the hollow hydraulic cylinder during the measurement process, thus protecting the equipment.

[0022] Optionally, the locking sleeve consists of two arc-shaped plates arranged opposite each other, with threads on the inner wall of the locking sleeve, and the outer diameter of the locking sleeve being larger than the inner diameter of the bottom end of the fixed sleeve, and being able to be inserted into the fixed sleeve.

[0023] By adopting the above technical solution, the locking sleeve is provided with two pieces. Since the inner wall of the fixing sleeve is inclined, the fixing sleeve will close the locking sleeves on both sides of the steel bar during the rising process, which will help to fix the steel bar more firmly.

[0024] Optionally, corresponding scales are engraved on the two ends of the arc surfaces of the lower base and the upper base.

[0025] By adopting the above technical solution, the tilt angle between the lower base and the upper base can be adjusted in advance to be equal to the angle formed by the concrete surface and the pre-embedded steel bar, which makes it easy to insert the base and the pull-out instrument onto the pre-embedded steel bar.

[0026] In summary, this application has the following technical effects:

[0027] 1. By setting a lower base with an arc surface and a matching upper base, the tester can easily change the pull-out angle;

[0028] 2. By setting a fixing component inserted into the central control hydraulic cylinder, it is easy to fix the steel bar to be tested;

[0029] 3. By setting graduations on both ends of the arc surfaces of the lower and upper bases, it is easier to adjust the pull-out instrument to the same angle as the steel bar to be tested. Attached Figure Description

[0030] Figure 1 This is a structural diagram of the object of this application;

[0031] Figure 2This is a structural diagram of the lower base and upper base of this application;

[0032] Figure 3 This is a partial cross-sectional view of this application.

[0033] Explanation of reference numerals in the attached drawings: 1. Lower base; 11. Communicating hole; 12. Sliding groove; 13. Fixing groove; 2. Upper base; 21. Sliding block; 22. Threaded hole; 23. Through hole; 3. Fixing bolt; 4. Pulling instrument body; 41. Hollow hydraulic cylinder; 42. Fixing assembly; 421. Fixing sleeve; 422. Locking sleeve; 43. Manual pump; 44. Oil supply pipe; 45. Digital pressure gauge; Detailed Implementation

[0034] The present application will be further described in detail below with reference to the accompanying drawings.

[0035] This application discloses a pre-embedded rebar pull-out instrument, referring to... Figure 1 The pull-out apparatus includes a lower base 1, an upper base 2 slidably connected to the lower base 1, and a pull-out apparatus body 4 fixedly connected to the upper base 2.

[0036] Reference Figure 2 The lower base 1 is a rectangular plate with a flat bottom and a concave arc surface on the top. The top surface of the lower base 1 has a connecting hole 11, sliding grooves 12 on both sides of the connecting hole 11, and fixing grooves 13 on both ends of the lower base 1. The connecting hole 11 is a strip-shaped hole, its length extending along the width of the lower base 1 and located in the middle of the top surface of the lower base 1. The depth of the connecting hole 11 is equal to the height of the lower base 1 and connects the concave arc surface and the bottom surface. The length of the connecting hole 11 is less than the width of the lower base 1, and both ends of the connecting hole 11 are closed. The width of the connecting hole 11 is greater than the outer diameter of the embedded reinforcing steel, allowing the lower base 1 to be fitted onto the embedded reinforcing steel.

[0037] Reference Figure 2 The sliding groove 12 has a T-shaped cross-section and two grooves. The two sliding grooves 12 are spaced apart along the length of the lower base 1 at the midpoints of opposite sides of the connecting hole 11. The length of the sliding groove 12 is equal to the length of the concave arc surface of the lower base 1 and connects the opposite sides of the lower base 1. The width of the opening of each sliding groove 12 is less than the width of its bottom and the width of the connecting hole 11. The length direction of the sliding groove 12 is parallel to the length direction of the connecting hole 11. Two fixed grooves 13 are perpendicularly formed at the edges of the arc surfaces at both ends of the lower base 1, and both ends of the fixed grooves 13 are closed. The depth of the fixed grooves 13 is connected to the sliding grooves 12. Scales are engraved on the upper groove walls at both ends of the lower base 1, with the scales starting from the midpoint of the edge of the concave arc surface of the lower base 1 and extending along the length of the edge of the concave arc surface of the lower base 1.

[0038] Reference Figure 2The upper base 2 is a rectangular plate with a flat top surface and a convex bottom surface. The length and width of the upper base 2 are equal to those of the lower base 1. The convex surface of the upper base 2 matches the concave arc surface of the lower base 1, and the upper base 2 can rotate on the lower base 1 to adjust the inclination of its top surface. Two sliding blocks 21, which are adapted to the sliding groove 12, are fixedly connected at intervals on the convex surface of the upper base 2. The sliding blocks 21 are slidably inserted into the sliding groove 12, and the length of the sliding blocks 21 is less than the length of the sliding groove 12. Multiple threaded holes 22 are provided on the sidewall of the sliding blocks 21, and these holes are evenly spaced along the length of the sliding blocks 21. The inner diameter of each threaded hole 22 is equal to the width of the fixed groove 13, and the depth of each threaded hole 22 is less than the thickness of the sliding block 21.

[0039] Reference Figure 2 A through hole 23 is vertically formed in the center of the top surface of the upper base 2. The through hole 23 connects the top surface and the convex surface of the upper base 2 and is connected to the connecting hole 11. The inner diameter of the through hole 23 is equal to the width of the connecting hole 11. The pre-embedded steel bar passes through the connecting hole 11 to exit the lower base 1 and through the through hole 23 to exit the upper base 2. Scales are engraved on the opposite end faces of the upper base 2, with the scales starting from the midpoint of the convex arc edge of the opposite end faces of the upper base 2 and extending around the arc surface.

[0040] Reference Figure 2 Four fixing bolts 3 are provided. One end of every two fixing bolts 3 passes through the fixing groove 13 and is threaded into the threaded hole 22. The outer diameter of the fixing bolt 3 is equal to the width of the fixing groove 13, and the length of the fixing bolt 3 is equal to the distance from the bottom of the threaded hole 22 to the outer opening of the fixing groove 13. The fixing bolts 3 are threaded into the threaded hole 22, and the inner wall of the fixing bolt 3 nut abuts against the two opposite groove walls of the fixing groove 13, thereby fixing the upper base 2 and the lower base 1.

[0041] Reference Figure 1 The main body 4 of the pull-out instrument includes a hollow hydraulic cylinder 41 fixed at one end to the upper base 2, a fixing component 42 sleeved on the upper end of the hollow hydraulic cylinder 41, an oil supply pipe 44 inserted at one end on the hollow hydraulic cylinder 41, a manual pump 43 connected to the other end of the oil supply pipe 44, and a digital pressure gauge 45 installed on the manual pump 43.

[0042] Reference Figure 3 The hollow hydraulic cylinder 41 is vertically fixed to the center of the top surface of the upper base 2. The hollow hydraulic cylinder 41 is coaxially arranged with the through hole 23. The inner diameter of the hollow hydraulic cylinder 41 is larger than the inner diameter of the through hole 23, and the pre-embedded steel bar can pass through the hollow hydraulic cylinder 41. The fixing component 42 is inserted into the opening at the end of the hollow hydraulic cylinder 41 away from the upper base 2. The fixing component 42 includes a fixing sleeve 421 inserted into the hollow hydraulic cylinder 41 and two locking sleeves 422 inserted into the fixing sleeve 421.

[0043] Reference Figure 3The fixing sleeve 421 is a round tube with an outer edge, which is fixed to the edge of one end of the tube opening. The inner wall of the fixing sleeve 421 gradually thickens from the outer edge to the other end, forming an inclined surface. The inner diameter of the tube opening of the fixing sleeve 421 away from the outer edge is equal to the inner diameter of the through hole 23, and it can be fitted onto the pre-embedded reinforcing bar. The outer diameter of the fixing sleeve 421 is equal to the inner diameter of the opening of the movable end of the hollow hydraulic cylinder 41, and it can be inserted into the opening. The length of the fixing sleeve 421 is less than the length of the hollow hydraulic cylinder 41. The fixing sleeve 421 is inserted into the opening of the movable end of the hollow hydraulic cylinder 41, with the outer wall of the fixing sleeve 421 fitting against the inner wall of the hollow hydraulic cylinder 41, and the edge of the fixing sleeve 421 fitting against the edge of the opening of the movable end of the hollow hydraulic cylinder 41.

[0044] Reference Figure 3 The locking sleeve 422 is an arc-shaped plate with an outer edge, and two arc-shaped plates are arranged opposite each other to form a circular tube. The inner wall of the locking sleeve 422 is threaded. The outer diameter of the two arc-shaped plates after merging is smaller than the inner diameter of the tube opening at the outer edge of the fixing sleeve 421, and the outer diameter of the two arc-shaped plates is larger than the inner diameter of the through hole 23. The two locking sleeves 422 can hold the pre-embedded steel bars inserted in the fixing sleeve 421 tightly, and a section opposite to the outer edge is inserted into the fixing sleeve 421.

[0045] Reference Figure 1 The manual pump 43 is connected to the hollow hydraulic cylinder 41 via the oil supply pipe 44. Pressing the manual pump 43 transfers oil from the pump 43 to the hollow hydraulic cylinder 41 through the oil supply pipe 44, raising the movable end of the cylinder 41. A digital pressure gauge 45 is fixed to the oil inlet of the manual pump 43 and is interconnected with both the pump 43 and the oil supply pipe 44. When the manual pump 43 supplies oil to the hollow hydraulic cylinder 41 through the oil supply pipe 44, the digital pressure gauge 45 can observe and record the pressure value.

[0046] When using a pull-out tester to test the anchorage force of embedded steel bars, if there is an angle between the embedded steel bar and the concrete surface, push the upper base 2 to slide it on the lower base 1 and tilt the upper base 2. By marking the scale on the upper base 2 and the lower base 1, make the tilt angle of the upper base 2 equal to the angle formed by the embedded steel bar and the concrete surface. Then, thread the fixing bolt 3 through the fixing groove 13 and connect it to the sliding block 21, and make the inner wall of the nut of the fixing bolt 3 abut against the groove of the fixing groove 13, thereby fixing the upper base 2 and the lower base 1. The pull-out tester is then sequentially fitted onto the embedded steel bar through the connecting hole 11, the through hole 23, and the hollow hydraulic cylinder 41. The fixing sleeve 421 is fitted onto the steel bar and inserted into the hollow hydraulic cylinder 41, so that the outer edge of the fixing sleeve 421 fits against the open end of the hollow hydraulic cylinder 41. Then, the locking sleeve 422 is used to hold the steel bar tightly and insert a section into the fixing sleeve 421. The hollow hydraulic cylinder 41 is raised by pressing the manual pump 43, causing the fixing sleeve 421 to abut against the locking sleeve 422. The two locking sleeves 422 approach each other and clamp the reinforcing bar. The pre-embedded reinforcing bar is pulled out by raising the hollow hydraulic cylinder 41, and the pressure value is read by the digital pressure gauge 45 to obtain the anchorage force of the pre-embedded reinforcing bar.

[0047] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A pre-embedded reinforcement bar pull-out apparatus, characterised in that: The utility model relates to a kind of steel bar pull-out tester, including lower base (1), upper base (2), fixed bolt (3) and pull-out tester body (4), the lower base (1) is rectangular plate with concave arc top surface, lower base (1) is equipped with the communicating hole (11) for being inserted into the steel bar to be measured and being communicated with concave arc surface and bottom surface, and sliding groove (12) with cross section being T is equipped on lower base (1) and is spaced apart from the communicating hole (11), the length direction of the sliding groove (12) is parallel with the length direction of communicating hole (11) each other; The upper base (2) is rectangular plate with convex arc bottom surface, the convex arc surface of upper base (2) is matched with the concave arc surface of lower base (1), and the sliding block (21) matched with sliding groove (12) is fixedly connected on the convex arc surface of upper base (2), and the sliding block (21) is slidably inserted into sliding groove (12), and the through hole (23) for being inserted into the steel bar to be measured is equipped in the middle of the top surface of upper base (2), the through hole (23) is communicated with the top surface and bottom surface of upper base (2), the inner diameter of through hole (23) is equal to the width of communicating hole (11), the fixed bolt (3) is detachably connected with sliding block (21) by being arranged in the end surface of lower base (1), and the pull-out tester body (4) is fixedly connected in the middle of upper base (2).

2. A pre-embedded reinforcement bar pull-out apparatus according to claim 1, wherein: The end surface of the lower base (1) is provided with a fixed groove (13) communicated with the sliding groove (12), the fixed groove (13) is arc-shaped and consistent with the curvature of the concave arc surface of the lower base (1), and the fixed bolt (3) is arranged in the fixed groove (13).

3. A pre-embedded reinforcement pulling instrument according to claim 2, characterized in that: The side wall of the sliding block (21) is provided with a plurality of threaded holes (22), the plurality of threaded holes (22) are spaced apart along the length direction of the side wall of the sliding block (21) away from the communicating hole (11), and matched with the fixed bolt (3).

4. A pre-embedded reinforcement pulling instrument according to claim 3, characterized in that: The communicating hole (11) is arranged in the middle of the concave arc surface of the lower base (1) along the width direction of the lower base (1), the length of the communicating hole (11) is less than the width of the lower base (1), and both ends of the communicating hole (11) are closed ends.

5. A pre-embedded reinforcement pulling instrument according to claim 4, characterized in that: The length of the sliding groove (12) is equal to the width of the lower base (1), and both ends of the sliding groove (12) are open.

6. A pre-embedded reinforcement pulling instrument according to claim 1, characterized in that: The pull-out tester body (4) includes a hollow hydraulic cylinder (41), the inner diameter of the end pipe of the hollow hydraulic cylinder (41) away from the upper base (2) is greater than the inner diameter of the through hole (23), and the hollow hydraulic cylinder (41) is fixedly connected to the upper base (2) and coaxially arranged with the through hole (23).

7. A pre-embedded reinforcement pulling instrument according to claim 6, characterized in that: The pull-out tester body (4) further includes a fixing assembly (42) arranged on the hollow hydraulic cylinder (41), the fixing assembly (42) includes a fixing sleeve (421) and a locking sleeve (422), the outer wall of the fixing sleeve (421) and the locking sleeve (422) is provided with an outer edge, and the inner wall of the fixing sleeve (421) is contracted from the top end to the bottom end and forms an inclined surface.

8. A pre-embedded reinforcement pulling instrument according to claim 7, characterized in that: The locking sleeve (422) is composed of two arc-shaped plates arranged oppositely, the inner wall of the locking sleeve (422) is provided with threads, the outer diameter of the locking sleeve (422) is greater than the inner diameter of the bottom end of the fixing sleeve (421), and the locking sleeve (422) can be arranged in the fixing sleeve (421).

9. The pre-embedded steel bar pull-out apparatus according to claim 1, wherein: The two ends of the arc surfaces of the lower base (1) and the upper base (2) are marked with corresponding scales.

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