Anchoring rod impact tensile mechanical property testing device and testing method

Abstract

Anchorage rod impact tensile mechanical property testing device and testing method, belong to the technical field of anchorage rod performance testing device, including external frame, external frame includes vertical frame, the limit plate is fixedly installed through bolt on the front and back sides of the bottom of vertical frame, the inner wall of the vertical column arranged along the vertical direction is installed with the sliding rail which is slidingly connected with the impact device, in order to control the impact hammer body to apply impact load along the vertical direction, the impact lock is installed in the middle lower part of the vertical column arranged along the vertical direction, the damper is symmetrically installed on the upper surface of the bottom beam at both ends, the prestressed device is installed at the center of the bottom beam, the impact frame is arranged on the upper surface of the bottom beam, the lifting device is installed on the upper beam. The testing device can simulate the impact load applied to the anchorage rod body, anchorage device or jointed anchorage body by instantaneous destruction of surrounding rock in the room, and the impact energy level and impact rate can be adjusted, so that the high-energy level impact load induced by deep engineering dynamic disaster can be more truly simulated.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of anchor rod performance testing devices, and particularly relates to an anchor rod impact tensile mechanical property testing device and a testing method. BACKGROUND

[0002] Anchor rod support improves the mechanical properties of surrounding rock mass, optimizes the stress distribution of rock mass, and enhances the bearing capacity of roadway surrounding rock, which effectively protects the supported body. However, in deep engineering under high stress environment, the strain energy accumulated by rock mass is extremely easy to release suddenly and violently along the free surface, causing brittle fracture of rock mass like explosion, i.e. rock burst disaster; rock burst has strong suddenness, randomness and violence, which causes great threat to personnel and equipment safety.

[0003] How to ensure that the roadway does not fail and break down when rock burst, impact ground pressure and other engineering disasters occur, and how to absorb the kinetic energy of the projectile rock mass, has been one of the important directions of research by domestic and foreign experts and scholars. Therefore, the mechanical response, failure state of anchor rod when impact load comes, and the impact and shear load performance of anchor rod have been paid more and more attention and research.

[0004] The current impact testing machine in the field of geotechnical engineering is the most typical vertical drop hammer dynamic impact testing machine, pendulum testing machine and pressure testing machine. The existing drop hammer impact device converts the vertical gravitational potential energy into impact kinetic energy, and the rod material is used for testing or the steel pipe is used for simulating drilling testing during the testing process, which is difficult to simulate the surrounding rock mass conditions under the actual engineering support, and pre-stress cannot be applied. In addition, the anchor rod test piece is fixed on the impact frame, and the frame gradually deforms due to fatigue when the long-term high-energy level impact test is performed, so that the operation safety is difficult to guarantee. The pendulum testing machine uses a pendulum to impact the load, and the pendulum mass is usually 0-2 t, which is difficult to apply high-energy impact load, and the floor area is large. In addition, the pendulum can only apply single-sided load to the impact rod, and eccentricity problem is easy to occur.

[0005] Therefore, the existing testing machines all have structural problems such as difficulty in simulating real surrounding rock conditions, inability to apply pre-stress, and frame deflection, fatigue and poor precision after long-term use. SUMMARY

[0006] The purpose of the present application is to provide an anchor rod impact tensile mechanical property testing device and a testing method, which can simulate the impact load applied to the anchor rod body, anchoring piece or jointed anchoring body by instantaneous destruction of surrounding rock in the laboratory, and can adjust the impact energy level and impact rate, thereby more truly simulating the high-energy level impact load induced by deep engineering dynamic disaster.

[0007] In order to achieve the above purpose, the present application adopts the following technical solutions:

[0008] An anchor rod impact tensile mechanical property testing device, comprising a lifting device, an external frame, an impact device, an impact frame, a prestressed device;

[0009] The external frame comprises a vertical frame which is a rectangular frame connected by a vertical column and a cross beam, limit plates are fixedly installed on the front and rear sides of the bottom of the vertical frame by bolts, a slide rail which is in sliding connection with the impact device is installed on the inner wall of the vertical column arranged in the vertical direction to control the impact hammer body to apply an impact load in the vertical direction, an impact lock is installed in the middle lower part of the vertical column arranged in the vertical direction, dampers are symmetrically installed at both ends of the upper surface of the cross beam at the bottom, the prestressed device is installed at the center of the bottom cross beam, an impact frame is arranged on the upper surface of the bottom cross beam, and the lifting device is installed on the cross beam at the upper part.

[0010] The lifting device comprises a winch installed at the top of the vertical frame, the output shaft of the winch is connected with one end of a steel wire rope, the other end of the steel wire rope is connected with an electromagnetic attractor, and the electromagnetic attractor is attracted to the top of the impact device by magnetic force.

[0011] The impact device comprises an impact drop hammer, the impact drop hammer is a hollow rectangular block, both ends of the impact drop hammer are fixedly connected with a guide frame through bolts, and the bottom of the impact drop hammer is seated on the upper surface of a buffer frame and fixedly installed on the buffer frame through bolts.

[0012] The guide frame comprises a connecting plate, symmetrically arranged guide plates are arranged at one end of the connecting plate and arranged along the length direction of the connecting plate, symmetrically arranged positioning grooves are arranged at the other end of the connecting plate and arranged along the width direction of the connecting plate, positioning keys are installed in the positioning grooves, symmetrically arranged bolt holes are arranged on the connecting plate between the two positioning keys, rollers are fixedly installed on the four corners of the connecting plate and the upper and lower ends of the guide plates through nuts, the rollers installed on the guide plates and the rollers installed on the connecting plate are arranged on the same side of the connecting plate, and the guide frame is fixedly integrated with the impact drop hammer by the positioning keys and the bolts.

[0013] The buffer frame comprises a square tube I and a square tube II, the square tube I and the square tube II are integrally connected by welding, the upper surface of the square tube I is higher than the upper surface of the square tube II, a clamping plate is welded to the upper surface of the square tube I, and bolt holes are arranged at the top of both ends of the clamping plate; the distance between the square tube I and the clamping plate is 3-10 cm, the clamping plate and the bolt holes are used for fixedly connecting the impact drop hammer, the lower surface of the square tube I is in contact with the impact lock to complete the locking action.

[0014] The impact locking device comprises a clamping body, which is fixed to the box body through an axle and can rotate by a certain angle along the axle, the upper rear end of the clamping body is connected with one end of a restoring spring, the other end of the restoring spring is fixed to the inner wall of the box body, a restoring bolt is screwed to the bottom of the rear end side wall of the box body, the end of the restoring bolt is located in the box body and matches with the groove at the bottom rear end of the clamping body, and an opening is formed in the top of the front end side wall of the box body to allow the clamping body to extend out of the box body; when the restoring bolt is rotated to move outward of the box body, the clamping body is pushed by the restoring spring, and the end of the clamping body will protrude to the outside of the box body, and the length of the protruding part is 0-10 cm; when the restoring bolt is rotated to move inward of the box body, the bottom of the clamping body is pressed by the restoring bolt, and the end of the clamping body will retract into the box body; the clamping body matches with the square tube I in the buffer frame to ensure the stability of the impact hammer body before the test.

[0015] The prestress device comprises a protective cover, which is fixedly installed at the center of the bottom beam of the vertical frame through bolts, a hollow tension-compression actuator is installed in the protective cover, the protective cover is a cylindrical steel cover for protecting the hollow tension-compression actuator to prevent the hollow tension-compression actuator from being damaged during the impact process, the output end of the hollow tension-compression actuator is connected with one end of a guide rod, the other end of the guide rod is connected with one end of a transmission chain, the other end of the transmission chain is connected with the four corners of an equal force plate, the equal force plate is a hollow I-shaped steel plate, and the prestress load is applied through the hollow tension-compression actuator and then transmitted to the transmission chain through the guide rod.

[0016] The impact frame comprises a test piece port and a stand, the bottom end of the stand is fixedly installed in the groove on the top of the sliding block, and the sliding block passes through the apertures in the bottom of the limiting plate, the sliding block is installed on the horizontal sliding rail fixed to the bottom beam of the vertical frame and can drive the impact frame to move on the horizontal sliding rail, the top of the stand is provided with the test piece port, the geometric center of the test piece port is located on the extended line of the axis of the hollow tension-compression actuator, the test piece port is located at the center of the top end of the impact frame, and the diameter is 300-450 mm; the anchor rod body on the test sample passes through the hollow part of the test piece port and receives the impact load as a whole.

[0017] The test sample has three forms, one is a concrete test piece, which can be divided into two types of half-section concrete test pieces and full-length concrete test pieces; the second is a steel pipe test piece, which can be divided into two types of half-section steel pipe test pieces and full-length steel pipe test pieces; and the third is a rod body test piece.

[0018] The full-length concrete test piece comprises a half-split mold; a plurality of fastening holes are formed on the outer wall of the half-split mold for fastening the half-split mold by bolts to form a cylindrical mold with an end plate at the top end; the cylindrical mold is in the shape of "T" as a whole, the upper end plate thereof is in contact with the test piece port to form axial constraint, and a pouring hole is formed on the upper end plate to facilitate pouring of mixed concrete into the half-split mold, the diameter of the pouring hole is 5-10 cm, the lower part of the cylindrical mold is in contact with the upper surface of the uniform force plate, and the cylindrical mold is filled with concrete to simulate the surrounding rock condition, the anchor rod body is arranged in the middle of the concrete, and the bottom end of the anchor rod body extends outside the cylindrical mold, and the size of the anchor rod body extending outside the cylindrical mold is 10-20 cm, the anchor rod body extending outside the cylindrical mold passes through the through hole in the center of the uniform force plate, and the anchor rod body at the lower part of the uniform force plate is provided with a tray, and the tray is fixed by a nut.

[0019] The half-split concrete test piece is different from the full-length concrete test piece in that the full-length half-split mold is divided into an upper half-split mold and a lower half-split mold, and the bottom end of the lower half-split mold is integrally formed with the uniform force plate.

[0020] The full-length steel pipe test piece comprises a steel pipe, a hollow pad plate is sleeved on the top of the steel pipe, an insertion hole is formed in the steel pipe extending to the upper part of the hollow pad plate, a bolt is installed in the insertion hole, a uniform force plate is sleeved on the bottom of the steel pipe, and the lower surface of the uniform force plate is flush with the lower surface of the steel pipe, an anchor rod body is arranged in the steel pipe, and the steel pipe is filled with concrete or resin anchoring agent, a tray is installed on the anchor rod body extending to the outside of the steel pipe, and a nut is screwed on the anchor rod body below the tray to limit the position of the tray; the steel pipe is provided with an insertion hole with a diameter of 2-4 cm at a position 10-15 cm away from the top, so that the bolt can pass through the insertion hole; the inner diameter of the hollow pad plate is 2-3 mm larger than the outer diameter of the steel pipe, and the outer diameter of the hollow pad plate is 330 mm, so that the bolt can be limited.

[0021] The half-split steel pipe test piece is the same in structure as the full-length steel pipe test piece, and the difference is that the steel pipe is divided into an upper steel pipe and a lower steel pipe.

[0022] The rod body test piece comprises a conical lock and an anchor rod body, the conical lock is composed of an outer steel sleeve and an inner conical lobe, the inner diameter of the inner conical lobe gradually decreases when the inner conical lobe is put into the outer steel sleeve, and the inner wall is further provided with a thread to lock rod bodies of different forms such as threaded steel, pipe joint, and glass steel, the top of the anchor rod body is provided with an upper tray matched with the test piece port, the anchor rod body on the top of the upper tray is provided with a lock, the bottom of the anchor rod body is provided with a uniform force plate and a lower tray, and a nut is screwed on the anchor rod body to limit the position of the lower tray.

[0023] A testing method of an anchor rod impact tensile mechanical property device, comprising the following steps:

[0024] Step 1, preparing a test sample

[0025] Making concrete test piece

[0026] After determining the type of test anchor and the surrounding rock condition, concrete with a strength comparable to that of the surrounding rock is cast; then the two half-mold molds are connected into a cylindrical mold using bolts, and concrete is cast into the cylindrical mold through the casting hole and cured; after the casting and curing are completed, a rock drill is used to drill holes in the concrete test piece to simulate a real borehole, and then the test anchor rod body is installed in the borehole according to the on-site construction method, with 10-20 cm of the anchor rod body exposed to install the lower tray and the nut, and the test sample installation is completed;

[0027] Making steel pipe test piece

[0028] After determining the type of test anchor and the surrounding rock condition, a steel pipe with fixed parameters is selected, and the test anchor rod body is installed; then a borehole with a diameter of 5-15 mm is drilled radially at a position 10-15 cm from the top of the steel pipe, and finally a pin with the same diameter as the borehole is inserted, and the test piece is installed.

[0029] Making rod body test piece

[0030] The rod body test piece has no surrounding rock condition, and after determining the type of test, it is ready for installation;

[0031] Step 2, test sample installation

[0032] Concrete test piece installation

[0033] When installing the concrete test piece, first align the test piece port of the impact frame with the axis of the concrete test piece, then place the concrete test piece into the test piece port, and contact and clamp the upper end plate of the half-mold mold with the bearing frame; after installing the concrete test piece, install the uniform force plate, pressure sensor, and anchor rod body in turn, with 10-15 cm of the anchor rod body exposed to install the lower tray and the nut, and the concrete test piece installation is completed, and the test is ready;

[0034] Steel pipe test piece installation

[0035] When installing the steel pipe test piece, first insert the pin into the pre-drilled borehole, then place the hollow gasket plate with an outer diameter equal to the protrusion of the anchor test piece and an inner diameter larger than the outer diameter of the steel pipe into the steel pipe test piece, and then place it into the test piece port with the axis aligned; thereafter, install the uniform force plate, pressure sensor, lower tray, and nut in turn on the other end of the steel pipe test piece, with close contact between them, and the steel pipe test piece installation is completed and the test is ready;

[0036] Rod body test piece installation

[0037] When installing the rod body test piece, first, the conical lock is fixedly connected with one end of the rod body, then a hollow gasket plate with the same outer diameter as the convex of the half-mold and an inner diameter larger than the outer diameter of the rod body is sleeved into the rod body, and the mutual axial alignment is ensured; then, the uniform force plate, the impact pressure sensor, the lower tray, and the nut are sequentially installed at the other end of the rod body test piece, and are in close contact with each other, and thus the installation of the rod body test piece is completed, waiting for the test;

[0038] Step 3, impact energy allocation

[0039] According to the law of conservation of energy: E p = mgh, where E p is the gravitational potential energy, m is the mass, g is the acceleration of gravity, and h is the height; according to Impact speed allocation, where v is the impact speed; the mass and impact speed are designed according to the above relationship, the weight is adjusted by the impact drop hammer, and the impact drop hammer height is controlled by the winch; after the weight adjustment is completed, the guide frame and the buffer frame are installed, and the winch is started to lift the impact hammer body to a fixed height through the electromagnetic attractor, and then the impact lock is opened to prevent the impact hammer body from falling accidentally;

[0040] Step 4, test piece centering and prestress application

[0041] The impact frame is moved to the test area through the horizontal slide rail, the front and rear limiting plates on the vertical frame are closed, the centering and positioning of the impact frame are completed, and the deviation in the impact process is prevented; when the test requires prestress application, the transmission chain is connected with the four ends of the uniform force plate, then the hollow pull-push actuator is started to drive the guide rod, and the prestress load is applied to the uniform force plate through the transmission chain; in addition, a high-torque wrench can be used to apply prestress to the nut; in addition, the high-torque wrench can be used to simulate the on-site prestress application;

[0042] Step 5, data acquisition

[0043] After the centering and prestress application of the impact frame are completed, the data acquisition system and the electromagnetic control system are started; the dynamic load pressure sensor is installed between the lower tray and the uniform force plate to monitor the impact load; the laser displacement sensor is installed on the impact frame to monitor the deformation of the test sample; the acceleration sensor and the level meter are installed on the impact drop hammer to monitor the impact kinetic energy; the lifting height of the impact drop hammer is obtained through the lifting length of the steel wire rope; the data collected by the above sensors is transmitted to the data acquisition system through electrical signals;

[0044] Step 6, start the test

[0045] After the above steps are completed, the rotating knob impact lock retracts the clamping body into the box body to ensure smooth sliding of the sliding way; the electromagnetic attractor is controlled to release the impact drop hammer, which impacts in the vertical direction under the constraint of the guide frame and the vertical frame sliding way; after the impact drop hammer collides with the uniform force plate, the impact load acts on the lower tray and the anchor rod body through the uniform force plate, so that the purpose of testing the mechanical properties of the anchor body is achieved; when the impact load is too large or the impact stroke is large, the buffer frame will be in contact with the damper to absorb the remaining impact energy and avoid damage to the experimental instrument caused by residual impact;

[0046] Step 7, end of test

[0047] After the impact is completed, the collected data is saved; then the winch is controlled to lift the impact drop hammer to a certain height, the restoring bolt of the rotating knob impact lock makes the clamping body exposed outside the box body, and the impact drop hammer is locked; after the above operations are completed and safety is confirmed, the impact frame is moved to the outside of the test area through the horizontal sliding rail, the test sample is disassembled, and the test is completed.

[0048] The technical effects of the present application are:

[0049] (1) The present application realizes the testing function of concrete test pieces, steel pipe test pieces, rod body test pieces and half-section test pieces. Different wall thickness steel pipes and different strength concrete test pieces meet the testing needs of anchor bodies under different lithology and different boundary conditions.

[0050] (2) The present application can simulate two kinds of precise prestress application methods of field and indoor, realize the precise application of different gradient prestress loads of anchor rod bodies or anchor test pieces through the prestress device, simulate the field prestress application method through the torque wrench, and meet the testing needs of anchor bodies under different prestress conditions.

[0051] (3) The present application can precisely adjust the height and mass of the impact drop hammer through the lifting device and the impact device, and realize the impact testing target under different energy levels and different impact rates.

[0052] (4) In terms of impact test safety, the present application controls the position of the impact hammer body through the impact lock, which plays the function of limit clamping; the damper is arranged to absorb the residual energy of the anchor body after being impacted, which plays the role of buffer protection. DETAILED DESCRIPTION

[0053] Figure 1 It is a oblique axial view of the anchor rod impact tensile mechanical property testing device of the present application;

[0054] Figure 2 It is a front view of the anchor rod impact tensile testing device of the present application;

[0055] Figure 3 It is a oblique axial view of the impact device of the present application;

[0056] Figure 4 Oblique axonometric view of the guiding frame of the present invention;

[0057] Figure 5 Oblique axonometric view of the buffer frame of the present invention;

[0058] Figure 6 Sectional view of the impact latch of the present invention;

[0059] Figure 7 Front view of the impact frame of the present invention;

[0060] Figure 8 Axonometric view of the impact frame of the present invention;

[0061] Figure 9 Sectional view of the full-length concrete specimen of the present invention;

[0062] Figure 10 Figure 9

[0063] Figure 11 Axonometric view of the full-length concrete specimen of the present invention;

[0064] Figure 12 Schematic view of the half-section concrete specimen of the present invention;

[0065] Figure 13 Schematic view of the full-length steel pipe specimen of the present invention; wherein Figure 13 a is a sectional view, Figure 13 b is Figure 13 a C-C toward the schematic view;

[0066] Figure 14 Schematic view of the half-section steel pipe specimen of the present invention;

[0067] Figure 15 Sectional view of the rod specimen of the present invention;

[0068] ​​1-lifting device, 11-winch, 12-steel wire rope, 13-electromagnetic attractor, 2-external frame, 21-vertical frame, 22-slideway, 23-limiting plate, 24-base, 3-impact device, 31-guide frame, 311-roller, 312-guide plate, 313-nut, 314-positioning key, 315-bolt hole, 316-positioning groove, 317-connection plate, 32-impact drop hammer, 33-buffer frame, 331-square tube I, 332-bolt hole, 333-clamping plate, 334-square tube II, 4-impact frame, 411-test piece port, 412-stand, 42-test sample, 421-half-split mold, 422-anchor rod body, 423-lower tray, 424-nut, 425-fastening hole, 426-pouring hole, 4211-upper half-split mold, 4212-lower half-split mold, 427-steel pipe, 428-hollow spacer plate, 429-latch, 4271-upper steel pipe, 4272-lower steel pipe, 430-external steel sleeve, 431-inner conical lobe, 432-upper tray, 43-force equalizing plate, 44-sliding block, 5-prestress device, 51-hollow tension-compression actuator, 52-guide rod, 53-transmission chain, 54-protective cover, 61-impact lock, 611-restoring spring, 612-locking body, 613-box body, 614-wheel axle, 615-restoring bolt, 62-damper. DETAILED DESCRIPTION

[0069] The application will be further described in detail below in combination with the drawings and examples.

[0070] As shown in Figure 1 and Figure 2 , an anchor rod impact tensile mechanical property testing device comprises a lifting device 1, an external frame 2, an impact device 3, an impact frame 4, and a prestress device 5.

[0071] The external frame 2 comprises a vertical frame 21 which is a rectangular frame formed by welding a stand and a crossbeam end to end, wherein the stand and the crossbeam are both made of channel steel, the bottom of the vertical frame 21 is provided with limiting plates 23 fixedly installed on both sides by bolts, the inner wall of the vertically arranged stand is provided with a slideway 22 in sliding connection with the impact device 3 to control the impact hammer body to apply an impact load in the vertical direction, the lower part of the vertically arranged stand is provided with an impact lock 61, the upper surface of the bottom crossbeam is symmetrically provided with dampers 62 at both ends, the center of the upper surface is provided with the prestress device 5, the prestress device 5 is installed at the center of the bottom crossbeam, the upper surface of the bottom crossbeam is provided with the impact frame 4, and the upper crossbeam is provided with the lifting device 1.

[0072] The lifting device 1 includes a hoist 11 mounted on the top of the vertical frame, the output shaft of the hoist 11 is connected with one end of a steel wire rope 12, the other end of the steel wire rope 12 is connected with an electromagnetic attractor 13, the electromagnetic attractor 13 is attracted on the top of the impact device 3 by magnetic force; the impact device 3 is lifted to the designed height by rotating the steel wire rope 12 to drive the electromagnetic attractor 13, so that the impact device 3 obtains initial impact kinetic energy; the electromagnetic attractor 13 is a rectangular magnetic block, on one hand, it is pulled by the steel wire rope 12, on the other hand, it is closely adsorbed with the impact device 3 by high magnetic force, and the locking and releasing of the impact device 3 are controlled.

[0073] As shown in Figure 3 , the impact device 3 includes an impact drop hammer 32, the impact drop hammer 32 is a hollow rectangular block, both ends are fixedly connected with a guide frame 31 through bolts, and the bottom of both ends is seated on the upper surface of a buffer frame 33 and is fixedly installed on the buffer frame 33 through bolts.

[0074] As shown in Figure 4 , the guide frame 31 includes a connecting plate 317, one end of the connecting plate 317 is symmetrically provided with a guide plate 312, and the guide plate 312 is arranged along the length direction of the connecting plate 317, the other end of the connecting plate 317 is symmetrically provided with a positioning groove 316, and the positioning groove 316 is arranged along the width direction of the connecting plate 317, a positioning key 314 is installed in the positioning groove 316, a bolt hole 315 is symmetrically arranged on the connecting plate 317 between the two positioning keys 314, and a roller 311 is fixedly installed on the four corners of the connecting plate 317 and the upper and lower ends of the guide plate 312 through nuts, the rollers 311 installed on the guide plate 312 and the connecting plate 317 are arranged on the same side of the connecting plate 317, the rollers 311 provide a guide action along the slide rail 22, ensure that the impact load is applied to the impact frame 4 in the vertical direction, and the guide frame 312 is fixedly integrated with the impact drop hammer 32 by the positioning key 314 and the bolt.

[0075] As shown in Figure 5 , the buffer frame 33 includes a square tube I 331 and a square tube II 334, the square tube I 331 and the square tube II 334 are integrally connected by welding, and the upper surface of the square tube I 331 is higher than the upper surface of the square tube II 334, a clamping plate 333 is welded on the upper surface of the square tube I 331, and bolt holes 332 are arranged at the top of both ends of the clamping plate 333, when the impact energy is too large or the impact overload, the lower surface of the buffer frame 33 will impact the damper 62, preventing the impact drop hammer 32 from losing control and ensuring the safety of the test; the distance between the square tube I 331 and the clamping plate 333 is 3-10 cm, the clamping plate 333 and the bolt hole 332 are used to complete the fixed connection with the impact drop hammer 32, and the lower surface of the square tube I 331 is in contact with the impact lock 61 to complete the locking action.

[0076] As shown in Figure 6As shown, the impact latch 61 includes a latch body 612 fixed in the box body 613 through an axle 614 and rotatable at an angle along the axle 614, the upper rear end of the latch body 612 is connected with one end of a restoring spring 611, the other end of the restoring spring 611 is fixed on the inner wall of the box body 613, a restoring bolt 615 is screwed on the bottom of the rear end side wall of the box body 613, the end of the restoring bolt 615 is located in the box body 613 and matched with the groove at the bottom rear end of the latch body 612, and an opening is formed at the top of the front end side wall of the box body 613 for the latch body 612 to extend out of the box body 613. When the restoring bolt 615 is rotated to move outward of the box body 613, the latch body 612 is pushed by the restoring spring 611, and the end thereof will protrude to the outside of the box body 613, and the length of the protruding part is 0-10 cm; when the restoring bolt 615 is rotated to move inward of the box body 613, the bottom of the latch body 612 is pressed by the restoring bolt, and the end protruding part will be withdrawn into the box body 613. Through the cooperation of the latch body 612 and the square tube I 331 in the buffer bracket 33, the stability of the impact hammer body before the test is ensured.

[0077] As shown in Figure 7 and Figure 8 As shown, the prestress device 5 includes a protective cover 54 fixedly installed at the center of the bottom beam lower surface of the vertical frame 21, a hollow tension-compression actuator 51 is installed in the protective cover 54, the protective cover 54 is a cylindrical steel cover for protecting the hollow tension-compression actuator 51 to prevent damage to the hollow tension-compression actuator during impact, the output end of the hollow tension-compression actuator 51 is connected with one end of a guide rod 52, the other end of the guide rod 52 is connected with one end of a transmission chain 53, the other end of the transmission chain 53 is connected with the four corners of the uniform force plate 43, the uniform force plate 43 is a hollow I-shaped steel plate, and the prestress load is applied through the hollow tension-compression actuator 51, and then transmitted to the transmission chain 53 through the guide rod 52.

[0078] The impact frame 4 includes a test piece port 411 and a stand 412, the bottom end of the stand 412 is fixedly installed in the groove on the top of the sliding block 44, and the sliding block 44 passes through the openings in the bottom of the limiting plate 23, the sliding block 44 is installed on the horizontal sliding rail fixed on the bottom beam of the vertical frame 21 and can drive the impact frame 4 to move on the horizontal sliding rail, the top of the stand 412 is provided with the test piece port 411, and the geometric center of the test piece port 411 is located on the extension line of the axis of the hollow tension-compression actuator 51, the test piece port 411 is located at the center of the top end of the impact frame 4, and the diameter is 300-450 mm; the stand 412 is made of high-rigidity material and shaped like a "U", which serves to support the test sample and has a gap with the test sample 42 located at the geometric center of the stand 412 to reduce energy loss caused by friction; the anchor rod body 422 on the test sample 42 passes through the hollow part of the test piece port 411 and receives the impact load as a whole.

[0079] The test sample 42 has three forms, one is a concrete test piece, which can be divided into two types of half-split concrete test piece and full-length concrete test piece; the second is a steel pipe test piece, which can be divided into two types of half-split steel pipe test piece and full-length steel pipe test piece; the third is a rod body test piece.

[0080] As shown in Figure 9 and Figure 10 , the full-length concrete test piece includes a half-split mold 421; a plurality of fastening holes 425 are formed on the outer wall of the half-split mold 421 for fastening the half-split mold by bolts to form a cylindrical mold with an end plate at the top end; the cylindrical mold is in the shape of "T" as a whole, the upper end plate thereof is in contact with the test piece port 411 to form axial constraint, and a pouring hole 426 is formed on the upper end plate to facilitate pouring of mixed concrete into the half-split mold, the diameter of the pouring hole is 5-10 cm, the lower part of the cylindrical mold is in contact with the upper surface of the uniform force plate 43, and the cylindrical mold is filled with concrete to simulate the surrounding rock condition, the anchor rod body 422 is arranged in the middle of the concrete, and the bottom end of the anchor rod body 422 extends outside the cylindrical mold, and the size of the anchor rod body 422 extending outside the cylindrical mold is 10-20 cm, the exposed anchor rod body 422 passes through the through hole in the center of the uniform force plate 43, and the lower tray 423 is installed on the anchor rod body 422 at the lower part of the uniform force plate 43 and is fixed by the nut 424.

[0081] As shown in Figure 11 and Figure 12 , the half-split concrete test piece is different from the full-length concrete test piece in that the full-length half-split mold 421 is divided into an upper half-split mold 4211 and a lower half-split mold 4212, and the bottom end of the lower half-split mold 4212 is integrally formed with the uniform force plate 43.

[0082] As shown in Figure 13 , the full-length steel pipe test piece includes a steel pipe 427, a hollow backing plate 428 is sleeved on the top of the steel pipe 427, an insertion hole is formed in the steel pipe 427 above the hollow backing plate 428, and a latch 429 is installed in the insertion hole, the steel pipe 427 is sleeved with the uniform force plate 43 at the bottom, and the lower surface of the uniform force plate 43 is flush with the lower surface of the steel pipe 427, the anchor rod body 422 is arranged in the steel pipe 427, and the steel pipe 427 is filled with concrete, the anchor rod body 422 extending to the outside of the steel pipe 427 is provided with the lower tray 423, and the nut 424 is screwed on the anchor rod body 422 below the lower tray 423 to limit the position of the lower tray 423. The steel pipe 427 is provided with an insertion hole with a diameter of 2-4 cm at a position 10-15 cm away from the top, so that the latch can pass through the insertion hole. The inner diameter of the hollow backing plate 428 is 2-3 mm larger than the outer diameter of the steel pipe 427, and the outer diameter of the hollow backing plate 428 is 330 mm, which can limit the position of the latch.

[0083] AsFigure 14 As shown, the half-section steel pipe specimen has the same structure as the full-length steel pipe specimen, the only difference being that the steel pipe 427 is divided into an upper steel pipe 4271 and a lower steel pipe 4272.

[0084] like Figure 15 As shown, the rod specimen includes a conical lock and an anchor rod 422. The conical lock consists of an outer steel sleeve 430 and an inner conical flap 431. When the inner conical flap 431 is inserted into the outer steel sleeve 430, its inner diameter gradually decreases. In addition, the inner wall is provided with threads, which can lock rods of different forms such as threaded steel, pipe seams, and fiberglass. The top of the anchor rod 422 is equipped with an upper tray 432 that mates with the specimen port 411. The anchor rod 422 on the top of the upper tray 432 is equipped with a lock. The bottom of the anchor rod 422 is equipped with a force equalizing plate 43 and a lower tray 423. A nut 424 is screwed onto the anchor rod 422 to limit the position of the lower tray 423.

[0085] A test method for an anchor bolt impact tensile mechanical property device includes the following steps:

[0086] Step 1: Prepare test samples

[0087] Making concrete specimens

[0088] After determining the type of test anchor and the surrounding rock conditions, concrete with a strength equivalent to that of the surrounding rock is poured. Then, two half-section molds 421 are connected with bolts to form a cylindrical mold. Concrete is poured into the cylindrical mold through the pouring hole 426 and cured. After pouring and curing, a rock drilling machine is used to drill holes in the concrete specimen to simulate real drilling. Then, the anchor rod body 422 to be tested is installed into the drill hole according to the on-site construction method. The anchor rod body 422 is exposed 10-20cm to install the lower tray 423 and nut 424. After completion, the test sample 42 is installed.

[0089] Fabrication of steel pipe specimens

[0090] After determining the type of test anchor and the surrounding rock conditions, select a steel pipe 427 with fixed parameters and insert the anchor body 422 to be tested; then drill a hole with a diameter of 5-15 mm radially at 10-15 cm from the top of the steel pipe 427, and finally insert a pin 429 with the same diameter as the drill hole and wait for the test piece to be installed.

[0091] Fabrication of rod specimens

[0092] The rod specimen was in rock-free condition; once the test type was determined, it could wait for installation.

[0093] Step 2: Test Sample Installation

[0094] Concrete specimen installation

[0095] The completed concrete specimen is placed into the impact frame 4. The inner diameter of the specimen port 411 matches the outer diameter of the half-section mold 421, so that the concrete specimen can be placed in it. The "T"-shaped boss at the top of the half-section mold 421 is larger than the inner diameter of the specimen port 411, so that it can be firmly stuck on the impact frame 4. After the concrete specimen is placed in, the force equalizing plate 43, the impact pressure sensor, the lower tray 423, and the nut 424 are installed in sequence on the exposed end of the anchor rod body 422. After completion, wait for the test.

[0096] Steel pipe specimen installation

[0097] The steel pipe specimen, which has been prepared and inserted with the pin 429, is placed in the hollow pad 428. The inner diameter of the hollow pad 428 is slightly larger than the outer diameter of the steel pipe specimen. The whole thing can be locked onto the specimen port 411 of the impact frame 4. Then, it is installed into the impact frame 4 and centered. Finally, the force equalizing plate 43, the impact pressure sensor, the lower tray 423, and the nut 424 are installed in sequence. After completion, wait for the test.

[0098] Rod specimen installation

[0099] First, the conical lock is fixedly connected to one end of the anchor rod 422. Then, the anchor rod 422 is fitted into the upper tray 432. The inner diameter of the upper tray 432 is slightly larger than the outer diameter of the anchor rod 422 specimen. The whole piece can be locked onto the specimen port 411 of the impact frame 4. Then, the whole piece is installed into the impact frame 4 and aligned. The upper tray 432 is in close contact with the specimen port 411 of the impact frame 4 due to the fastening effect of the conical lock. After that, the "I"-shaped force equalizing plate 43, the impact pressure sensor, the lower tray 423, and the nut 424 are installed in sequence on the other end of the rod specimen. They are in close contact with each other. At this point, the rod specimen installation is completed and it is ready for testing.

[0100] Step 3: Adjusting the impact energy

[0101] According to the law of conservation of energy: Ep = mgh, where Ep is gravitational potential energy, m is mass, g is gravitational acceleration, and h is height, impact hammers 32 of different masses are assembled; for example, a 2t (2000kg) steel block is lifted to a height of 3m and released to generate 60kJ of impact energy (g is taken as 10m / s2); according to the adjustment of the impact rate, where v is the impact rate; for example, when lifted to 1.8m, the impact rate of the impact hammer 32 is 6m / s; after the counterweight is completed, the guide plate 312 and the buffer frame 33 are installed, and the winch 11 is started to lift the impact hammer 32 to a fixed height through the electromagnetic attractor 13, which can be adjusted according to experimental needs; then the reset bolt 615 of the knob impact lock 61 is turned, at which time the lock body 612 is pushed out of the box by the reset spring 611, thus preventing the impact hammer 32 from falling accidentally;

[0102] Step 4: Specimen centering and prestressing

[0103] The assembled impact frame 4 is moved to the test area by horizontal sliding rails, and then the limiting plate 23 on the vertical frame 21 is installed. After installation, the impact frame 4 is constrained by the horizontal sliding rails and the limiting plate 23 in the vertical direction of the hollow part of the impact drop hammer 32, and the device is centered at this time; when pre-stress needs to be applied, the transmission chain 53 is connected to the four ends of the uniform force plate 43, and then the hollow tension and compression actuator 51 is started to drive the guide rod 52, and then the pre-stress load is applied to the uniform force plate 43 through the transmission chain 53. In addition, a high-torque wrench can be used to apply pre-stress to the nut 424;

[0104] Step 5, data acquisition

[0105] After the impact frame 4 is centered and pre-stress is applied, the data acquisition system and the electromagnetic control system are turned on; the dynamic load pressure sensor is installed between the lower tray 423 and the uniform force plate 43 to monitor the impact load; the laser displacement sensor is installed on the impact frame 4 to monitor the deformation of the test sample 42; the acceleration sensor and the level meter are installed on the impact drop hammer 32 to monitor the impact kinetic energy; the lifting height of the impact drop hammer 32 is obtained by the lifting length of the steel wire rope 12; the data collected by the above-mentioned sensors is transmitted to the data acquisition system through electrical signals; the data acquisition system receives real-time data from the sensors on one hand, and adjusts the impact kinetic energy through the sensor data on the other hand;

[0106] Step 6, start test

[0107] After the above steps are completed, the knob impact lock 61 retracts the clamping body 612 into the box to ensure smooth sliding; the electromagnetic attractor 13 is controlled to release the impact drop hammer 32, which impacts in the vertical direction under the constraint of the sliding rails of the guide frame 31 and the vertical frame 21; after the impact drop hammer 32 collides with the uniform force plate 43, the impact load acts on the lower tray 423 and the anchor rod body 422 through the uniform force plate 43, thereby achieving the purpose of testing the mechanical properties of the anchor body; when the impact load is too large or the impact stroke is too large, the buffer frame 33 will contact the damper 62 to absorb the remaining impact energy and avoid damage to the experimental equipment caused by residual impact;

[0108] Step 7, test end

[0109] After the impact is completed, the collected data is saved; then the winch 11 is controlled to lift the impact drop hammer 32 to a certain height, and the recovery bolt 615 of the knob impact lock 61 exposes the clamping body 612 outside the box, locking the impact drop hammer 32; after confirming the safety of the above operation, the impact frame 4 is moved to the outside of the test area by the horizontal sliding rails, and the test sample 42 is disassembled, and the test is completed.

Claims

1. A device for testing the impact and tensile mechanical properties of anchor bolts, characterized in that, Includes lifting devices, external frames, impact devices, impact frames, and prestressed devices; The external frame includes a vertical frame, which is a rectangular frame welded together by first columns and crossbeams. Limiting plates are fixedly installed on the front and rear sides of the bottom of the vertical frame by bolts. A slide rail that is slidably connected to the impact device is installed on the inner wall of the vertically arranged first column to control the impact hammer to apply impact load in the vertical direction. An impact lock is installed in the lower middle part of the vertically arranged first column. Dampers are symmetrically installed at both ends of the upper surface of the bottom crossbeam. A prestressing device is installed on the upper surface at the center. The prestressing device is installed at the center of the bottom crossbeam. An impact frame is provided on the upper surface of the bottom crossbeam. A lifting device is installed on the upper crossbeam. The impact frame includes a specimen port and a second column. The bottom end of the second column is fixedly installed in the groove at the top of the slider, and both ends of the slider pass through the notch at the bottom of the limiting plate. The slider is installed on a horizontal slide rail fixed to the bottom beam of the vertical frame, which can drive the impact frame to move on the horizontal slide rail. The top of the second column is provided with a specimen port, and the geometric center of the specimen port is located on the extension line of the axis of the hollow tension-compression actuator. The specimen port is located at the center of the top of the impact frame and has a diameter of 300-450 mm. The anchor rod on the test sample is arranged through the hollow part of the test port.

2. The anchor bolt impact tensile mechanical property testing device according to claim 1, characterized in that: The lifting device includes a winch installed on the top of the vertical frame. The output shaft of the winch is connected to one end of a wire rope, and the other end of the wire rope is connected to an electromagnetic attractor. The electromagnetic attractor is magnetically attracted to the top of the impact device.

3. The anchor bolt impact tensile mechanical property testing device according to claim 1, characterized in that: The impact device includes an impact hammer, which is a hollow rectangular block. Both ends are fixedly connected to the guide frame by bolts, and the bottom two ends are respectively placed on the upper surface of the buffer frame and fixedly installed on the buffer frame by bolts.

4. The anchor bolt impact tensile mechanical property testing device according to claim 3, characterized in that: The guide frame includes a connecting plate. A guide plate is symmetrically arranged at one end of the connecting plate along its length. A positioning groove is symmetrically arranged at the other end of the connecting plate along its width. A positioning key is installed in the positioning groove. Bolt holes are symmetrically opened on the connecting plate between the two positioning keys. Rollers are fixedly installed at the four corners of the connecting plate and at the top and bottom ends of the guide plate by nuts. The rollers installed on the guide plate and the rollers installed on the connecting plate are all located on the same side of the connecting plate. The guide frame is fixed to the impact hammer as a whole by the positioning keys and bolts.

5. The anchor bolt impact tensile mechanical property testing device according to claim 3, characterized in that: The buffer frame includes square tube I and square tube II, which are welded together as one piece. The upper surface of square tube I is higher than the upper surface of square tube II. A clamping plate is welded to the upper surface of square tube I, and bolt holes are opened at the top of both ends of the clamping plate. The distance between square tube I and the clamping plate is 3-10 cm. The clamping plate and bolt holes are used to complete the fixed connection with the impact hammer. The lower surface of square tube I contacts the impact lock to complete the locking function.

6. The anchor bolt impact tensile mechanical property testing device according to claim 3, characterized in that: The impact lock includes a locking body, which is fixed to the housing by an axle and can rotate at a certain angle along the axle. The upper rear end of the locking body is connected to one end of a restoring spring, and the other end of the restoring spring is fixed to the inner wall of the housing. A restoring bolt is screwed to the bottom of the rear side wall of the housing, and the end of the restoring bolt is located inside the housing and engages with a groove at the bottom rear end of the locking body. An opening is provided at the top of the front side wall of the housing for the locking body to extend out of the housing. When the restoring bolt is rotated to move outward from the housing, the locking body is pushed by the restoring spring, and its end will protrude outward from the housing. When the restoring bolt is rotated to move inward from the housing, the bottom of the locking body is pressed by the restoring bolt, and the protruding end will retract into the housing. The locking body, in conjunction with the square tube I in the buffer frame, ensures the stability of the impact hammer before or during the test.

7. The anchor bolt impact tensile mechanical property testing device according to claim 1, characterized in that: The prestressing device includes a protective cover, which is bolted to the center of the lower surface of the bottom beam of the vertical frame. A hollow tension-compression actuator is installed inside the protective cover, which is a cylindrical steel cover used to protect the hollow tension-compression actuator and prevent it from being damaged during impact. The output end of the hollow tension-compression actuator is connected to one end of a guide rod, the other end of the guide rod is connected to one end of a transmission chain, and the other end of the transmission chain is connected to the four corners of the force equalizing plate. The prestress load is applied through the hollow tension-compression actuator and then transmitted to the transmission chain through the guide rod.

8. The anchor bolt impact tensile mechanical property testing device according to claim 1, characterized in that: The test samples come in three forms: concrete specimens, which can be divided into two categories: half-section concrete specimens and full-length concrete specimens; steel pipe specimens, which can be divided into two categories: half-section steel pipe specimens and full-length steel pipe specimens; and rod specimens. The full-length concrete specimen includes a half-section mold; the outer wall of the half-section mold has several fastening holes for bolts to pass through and fasten the half-section mold to form a cylindrical mold with an end plate at the top; the cylindrical mold is T-shaped in general, and its upper end plate contacts the specimen port to form axial constraint, and a pouring hole with a diameter of 5-10 cm is opened on the upper end plate to facilitate the injection of mixed concrete into the half-section mold. The lower part of the cylindrical mold contacts the upper surface of the pressure equalization plate. Concrete is filled inside the cylindrical mold to simulate the surrounding rock conditions. An anchor rod is set in the middle of the concrete, and the bottom end of the anchor rod extends to the outside of the cylindrical mold, with an extension of 10-20 cm to the outside of the cylindrical mold. The exposed anchor rod passes through the through hole at the center of the pressure equalization plate, and a tray is installed on the anchor rod at the lower part of the pressure equalization plate and fixed with nuts. The difference between the semi-section concrete specimen and the full-length concrete specimen is that the full-length semi-section mold is divided into two parts: an upper semi-section mold and a lower semi-section mold, and the bottom end of the lower semi-section mold is integrally formed with the force plate. The full-length steel pipe specimen includes a steel pipe with a hollow pad fitted at the top. An insertion hole is formed on the portion of the steel pipe extending above the hollow pad, and a pin is installed within the insertion hole. A force-equalizing plate is fitted at the bottom of the steel pipe, with its lower surface flush with the lower surface of the steel pipe. An anchor rod is installed inside the steel pipe, and the pipe is filled with concrete or resin anchoring agent. A tray is installed on the portion of the anchor rod extending to the outside of the steel pipe, and a nut is screwed onto the anchor rod below the tray to limit and fix the position of the tray. An insertion hole with a diameter of 2-4 cm is formed 10-15 cm from the top of the steel pipe, allowing the pin to pass through. The inner diameter of the hollow pad is 2-3 mm larger than the outer diameter of the steel pipe, which helps to limit the pin's position. The half-section steel pipe specimen has the same structure as the full-length steel pipe specimen, the only difference being that the steel pipe is divided into an upper steel pipe and a lower steel pipe; The rod specimen includes a conical lock and an anchor rod. The conical lock consists of an outer steel sleeve and an inner conical disc. The inner diameter of the inner conical disc gradually decreases when it is inserted into the outer steel sleeve. In addition, the inner conical disc is also provided with threads for locking the threaded steel rod or fiberglass rod. The top of the anchor rod is equipped with an upper tray that mates with the end of the specimen. The anchor rod is equipped with a lock on the top of the tray. The bottom of the anchor rod is equipped with a force equalizing plate and a lower tray. A nut is screwed onto the anchor rod to limit the position of the lower tray.

9. The test method for the impact tensile mechanical properties of an anchor bolt according to claim 1, characterized in that, Includes the following steps: Step 1: Prepare test samples Making concrete specimens After determining the type of anchor bolt and the surrounding rock conditions, concrete with a strength equivalent to that of the surrounding rock is poured. Then, two half-section molds are connected with bolts to form a cylindrical mold. Concrete is poured into the cylindrical mold through the pouring hole and cured. After pouring and curing, a rock drilling machine is used to drill holes in the concrete specimen to simulate real drilling. Then, the anchor bolt to be tested is installed into the drill hole according to the on-site construction method, with 10-20cm of the anchor bolt exposed to install the lower plate and nut. After completion, the test sample is installed. Fabrication of steel pipe specimens After determining the type of anchor bolt to be tested and the surrounding rock conditions, select a steel pipe with fixed parameters and install the anchor bolt body to be tested; then drill a hole with a diameter of 5-15 mm radially at 10-15 cm from the top of the steel pipe, and finally insert a pin with the same diameter as the drill hole and wait for the specimen to be installed. Fabrication of rod specimens The rod specimen was in rock-free condition; once the test type was determined, it could wait for installation. Step 2: Test Sample Installation Concrete specimen installation When installing the concrete specimen, first align the specimen port of the impact frame with the axis of the concrete specimen, then place the concrete specimen into the specimen port, and contact and snap it together with the load-bearing frame through the upper end plate of the half-section mold; after the concrete specimen is installed, install the force equalization plate and pressure sensor in sequence, and expose 10-15 cm of the anchor rod to install the lower tray and nut. At this point, the installation of the concrete specimen is completed and it is ready for testing. Steel pipe specimen installation When installing the steel pipe specimen, first insert the pin into the pre-drilled hole, then fit a hollow pad with an outer diameter the same as the protrusion of the anchoring specimen and an inner diameter larger than the outer diameter of the steel pipe onto the steel pipe specimen. After that, place it into the end of the specimen and ensure that the axis is aligned. Then, install the force equalizing plate, pressure sensor, lower tray, and nut in sequence on the other end of the steel pipe specimen, ensuring that they are in close contact with each other. At this point, the installation of the steel pipe specimen is complete and it is ready for testing. Rod specimen installation When installing the rod specimen, first fix the conical lock to one end of the rod. Then, insert the hollow pad with an outer diameter the same as the protrusion of the half-section mold and an inner diameter larger than the outer diameter of the rod into the rod, ensuring that the axes are aligned. After that, install the force equalizing plate, impact pressure sensor, lower tray, and nut on the other end of the rod specimen in sequence, ensuring that they are in close contact with each other. At this point, the installation of the rod specimen is complete and it is ready for testing. Step 3: Adjusting the impact energy According to the law of conservation of energy: E p = mgh, where E p Let m be the gravitational potential energy, g be the mass, g be the gravitational acceleration, and h be the height; according to According to the adjustment of the impact rate, where v is the impact rate; design the mass and impact rate according to the above relationship, use the impact hammer for counterweighting, and control the height of the impact hammer with the winch; after the counterweight is completed, install the guide frame and buffer frame, and start the winch to lift the impact hammer to a fixed height through the electromagnetic attractor, and then open the impact lock to prevent the impact hammer from falling accidentally. Step 4: Specimen centering and prestressing The impact frame is moved to the test area via a horizontal slide rail. The front and rear limit plates on the vertical frame are closed to complete the centering and positioning of the impact frame and prevent skewing during the impact process. When prestress needs to be applied during the test, the transmission chain is connected to the four ends of the force equalizing plate. Then, the hollow tension-compression actuator is activated to drive the guide rod and apply the prestress load to the force equalizing plate through the transmission chain. Alternatively, a high-torque wrench can be used to apply prestress to the nut. In addition, prestress can be applied in the field using a high-torque wrench to simulate the process. Step 5: Data Acquisition After the impact frame is aligned and prestressed, the data acquisition system and electromagnetic control system are activated. The dynamic load pressure sensor is installed between the lower tray and the force equalization plate to monitor the impact load. The laser displacement sensor is installed on the impact frame to monitor the deformation of the test sample. The acceleration sensor and level are installed on the impact hammer to monitor the impact kinetic energy. The lifting height of the impact hammer is obtained by the lifting length of the steel wire rope. The data collected by the above sensors are transmitted to the data acquisition system through electrical signals. Step 6: Begin the experiment After completing the above steps, the knob impact lock retracts into the box to ensure the slide is unobstructed; control the electromagnetic actuator to release the impact hammer, which impacts vertically under the constraint of the guide frame and the vertical frame slide; after the impact hammer collides with the force equalizing plate, the impact load acts on the lower tray and anchor rod through the force equalizing plate, thereby achieving the purpose of testing the mechanical properties of the anchor body; when the impact load is too large or the impact stroke is too large, the buffer frame will contact the damper to absorb the remaining impact energy and avoid residual impact from damaging the experimental instrument; Step 7, End of Experiment After the impact is completed, the collected data is saved; then, the winch is controlled to lift the impact hammer to a certain height, and the reset bolt of the impact lock is turned to expose the lock body outside the box, locking the impact hammer; after the above operations are completed and safety is confirmed, the impact frame is moved outside the test area via the horizontal slide rail, the test sample is disassembled, and the test ends.

Images