Anchor bolt impact testing device and testing method

Abstract

The application relates to the technical field of anchorage performance testing, in particular to an anchorage impact testing device and a testing method, which comprises the following steps: a concrete test block is hung on a support through an anchorage to be tested; the support is rapidly accelerated to rise through external force driving; the instantaneous acceleration of upward impact is combined with the inertial force acceleration of the concrete test block itself to realize loading of a test impact load for separating the concrete test block and the anchorage to be tested. The technical scheme of the application is different from common testing methods; the application adopts the mode of upward impact to generate acceleration to load the impact load, and relevant testing standards of the test are formulated, which is favorable for efficiently and accurately studying the performance of the anchorage under the conditions of a cracked concrete base material, a large edge distance, a large spacing and an axial direct impact load, the impact load does not need to be loaded by accurately aiming at the anchorage to be tested through a drop hammer, the test impact load is realized, the test operation difficulty is reduced, and the anchorage impact test can be efficiently and accurately performed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of anchor performance testing, in particular to an anchor impact test device and a test method. BACKGROUND

[0002] Mechanical anchor fixing is one of the most commonly used post-fixing methods in concrete structure engineering. The friction generated by the anchor expansion plate or the locking force generated by the anchor and the concrete block is used to fix the fixed object on the concrete block to achieve the fixing effect. Therefore, the reliability of anchoring is directly related to the safety of engineering operation. In some important projects, such as nuclear power plants and nuclear facilities, civil defense projects, if an accidental impact load acts on the anchor, it may cause displacement of important pipelines, equipment, and supports to be too large and fail, causing significant personnel casualties or economic losses, or causing major secondary accidents. Therefore, it is necessary to reduce the impact of such small probability events that may have serious consequences, and thus the reliability requirements for mechanical anchor anchoring are much higher than those of general construction projects.

[0003] The performance of mechanical anchors under static load and seismic load has been quite mature, such as the European ETA specification and the American ACI specification. However, there is no specification to guide the performance of mechanical anchors under impact load, and there is also little theoretical research and practical experience.

[0004] Moreover, the market uses a falling hammer to impact the anchor downward, which has a single test condition and is not conducive to studying the performance of the anchor under crack concrete base material, large edge distance, large spacing, and axial direct impact load. SUMMARY

[0005] The present application provides an anchor impact test device and a test method to improve the following technical problems:

[0006] Most of the domestic and foreign anchors use a falling hammer to impact the anchor downward, and there is no precedent or related test standard for loading impact load by upward impact acceleration.

[0007] In a first aspect, the present application provides an anchor impact test method, which adopts the following technical solution:

[0008] An anchor impact test method, comprising the following steps: suspending a concrete block on a support through an anchor to be tested, driving the support to rapidly accelerate upward by an external force, and combining the instantaneous acceleration of upward impact with the inertial force acceleration of the concrete block itself to achieve a test impact load for separating the concrete block and the anchor to be tested.

[0009] In an implementable technical solution of the present application, a single concrete test block is suspended and fixed by multiple anchor bolts to be tested, and the upper surface of the concrete test block is provided with multiple downwardly arranged drill holes, and a parallel crack penetrating all the drill holes is processed at the bottom of the concrete test block, and the width of the parallel crack is between 0.6-0.8 mm.

[0010] In an implementable technical solution of the present application, all the anchor bolts to be tested are subjected to twice loading of the same impact load, and no operation is performed on the anchor bolts to be tested between the twice impact loadings, and under the twice impact loadings, the displacement s1 and the displacement s2 of the concrete test block are measured by a displacement sensor; if the impact test evaluation of the anchor bolt to be tested meets the following standards, it is considered that the anchor bolt exhibits good impact bearing performance on the impact and severely cracked concrete base material:

[0011] The 90% quantile of the displacement s1 under the first impact loading is not greater than 10 mm;

[0012] The standard deviation of the displacement s1 under the first impact loading is not greater than 3 mm;

[0013] The expected value of the displacement s1 under the first impact loading is greater than the expected value of the displacement s2 under the second impact loading.

[0014] In a second aspect, the present application provides an anchor bolt impact test device, which adopts the following technical solution:

[0015] An anchor bolt impact test device is based on the anchor bolt impact test method described above, and the test device comprises a base, a fixed support, a lifting platform, a movable support, multiple guide rails and multiple impact air cylinders, the bottom of the fixed support is fixedly installed on the base, the guide rails are vertically arranged and fixed between the top of the fixed support and the base, the lifting platform is horizontally arranged and slidably penetrates through the guide rails, the movable support is installed on the lifting platform, the impact air cylinders are vertically arranged and fixed between the bottom of the lifting platform and the base, the top of the movable support is provided with an anchoring seat, a concrete test block is suspended and fixed at the bottom of the anchoring seat by multiple anchor bolts to be tested, a displacement sensor is further arranged on the anchoring seat, multiple guide rails and multiple impact air cylinders are spaced apart and arranged on the periphery of the lifting platform, multiple impact air cylinders work synchronously and are used to provide the instantaneous acceleration of upward impact of the lifting platform.

[0016] In an implementable technical solution of the present application, multiple pneumatic clamps are installed on the periphery of the lifting platform, the pneumatic clamps are arranged one-to-one corresponding to the guide rails, the guide rails slidably penetrate through the pneumatic clamps, and multiple pneumatic clamps work synchronously to quickly brake the lifting platform which is impacted upward at high speed.

[0017] In an implementation of the present application, the periphery of the lifting platform is provided with a thickened structure, a cavity is arranged on the thickened structure, the pneumatic clamp is fixedly installed in the cavity, and the opening of the cavity is sealed by a cover plate.

[0018] In an implementation of the present application, the top of the fixed support is further provided with a plurality of elastic buffers, the elastic buffers are arranged in one-to-one correspondence with the guide rails, and the elastic buffers are used to flexibly contact the periphery of the lifting platform subjected to high-speed upward impact.

[0019] In an implementation of the present application, the elastic buffer comprises a rubber block and a plurality of sets of buffer bolts, the top of the guide rail penetrates through the rubber block, and the rubber block is detachably assembled with the top of the fixed support by the plurality of sets of buffer bolts.

[0020] In an implementation of the present application, the movable support comprises a rectangular top frame and a plurality of vertical columns, at least four vertical columns are connected to the bottom of four corners of the rectangular top frame, and the rectangular top frame and the vertical columns are both made of I-beams.

[0021] In an implementation of the present application, the anchor seat comprises a horizontally arranged anchor plate and a plurality of vertically arranged suspension rods, the top of the suspension rod is fixedly bolted to the top of the movable support, the bottom of the suspension rod is fixed to the anchor plate, the anchor plate is provided with a plurality of spaced anchor bolt holes, the anchor bolt to be tested is fixed and vertically penetrates through the anchor bolt hole, the anchor plate is further provided with a mounting hole, the displacement sensor is fixed in the mounting hole, and the bottom detection surface of the displacement sensor is flush with the lower surface of the anchor plate.

[0022] In summary, the present application has at least one of the following beneficial technical effects:

[0023] The present application uses the upward impact to generate acceleration to load the impact load, and formulates the relevant test standards of the test, which is beneficial to efficiently and accurately study the performance of the anchor bolt under the conditions of the cracked concrete base material, large edge distance, large spacing and axial direct impact load, and further provides beneficial experience for the impact resistance performance research of the mechanical anchor bolt.

[0024] Unlike the common test method, the impact load does not need to be accurately aligned with the anchor bolt to be tested by a drop hammer, but only needs to be driven by an external force to quickly accelerate the support to upwardly impact, so as to realize the test impact load for separating the concrete test block and the anchor bolt to be tested, reduce the test operation difficulty, and be beneficial to efficiently and accurately perform the anchor bolt impact test. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 is a structural schematic diagram of an anchor impact test device according to an embodiment of the present application.

[0027] Figure 2 is a structural schematic diagram of a slitting mechanism according to an embodiment of the present application.

[0028] Figure 3 is a principle diagram of three common types of anchors according to an embodiment of the present application.

[0029] Explanation of reference signs:

[0030] 100, base; 200, fixed support; 300, displacement sensor; 400, ball; 1, lifting platform; 11, concave cavity; 12, cover plate; 13, weight-reducing notch; 14, light shield; 2, movable support; 21, rectangular top frame; 22, stand column; 3, guide rail; 4, impact cylinder; 5, anchoring seat; 51, anchoring plate; 52, suspension rod; 6, pneumatic clamp; 7, elastic buffer part; 71, rubber block; 72, buffer bolt; 8, slitting mechanism; 81, linear slide module; 82, jacking cylinder; 83, mounting seat; 84, cutting disc; 85, driving motor; 9, photoelectric gate. DETAILED DESCRIPTION

[0031] In order to make the technical problems, technical solutions and beneficial effects of the present application more clearly understood, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0032] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0033] It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate directions or positions based on the directions or positions shown in the drawings and are used for convenience in describing the present application and simplifying the description, and thus cannot be construed as indicating or implying that a device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus cannot be understood as limiting the present application.

[0034] In addition, the terms "first", "second", "third", etc. are used only for descriptive purposes and cannot be construed as indicating or implying relative importance or an indicated number of technical features. Therefore, features defined as "first", "second", etc. can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0035] The following will be described in detail in combination with the accompanying drawings. Figures 1-2 The present application will be further described in detail.

[0036] The embodiments of the present application disclose an anchor impact test method, comprising the following steps: suspending a concrete test block on a support through an anchor to be tested, driving the support to rapidly accelerate upward by an external force, combining the instantaneous acceleration of upward impact with the inertial force acceleration of the concrete test block itself to realize loading out of a test impact load N test,shock .

[0037] Wherein a single concrete test block is suspended and fixed through multiple anchors to be tested, and the upper surface of the concrete test block is provided with multiple downward arranged drill holes, and a parallel crack penetrating all the drill holes is processed at the bottom of the concrete test block, and the parallel crack width is between 0.6-0.8mm.

[0038] And all the anchors to be tested are subjected to the same impact load N test,shock , and no operation is performed on the anchors to be tested between the two impact loadings, and the vertical displacement s1 and displacement s2 of the concrete test block are measured by a displacement sensor under the two impact loadings N test,shock ; if the impact test evaluation of the anchor to be tested meets the following standards, it is considered that the anchor to be tested performs well in the impact and severe cracking of the concrete base material.

[0039] The 90% quantile of the displacement s1 under the first loading impact is not greater than 10mm;

[0040] The standard deviation of the displacement s1 under the first loading impact is not greater than 3mm;

[0041] The expected value of displacement s1 under the first loading impact is greater than the expected value of displacement s2 under the second loading impact.

[0042] The anchor bolt impact test method of the embodiments of the present application has the following beneficial technical effects:

[0043] Since the common test method generally uses the falling hammer impact method to perform impact load test on the anchor bolt, the falling hammer needs to accurately impact the anchor bolt on the concrete test block. After the anchor bolt is impacted, relative displacement occurs between the anchor bolt and the concrete test block. Then, the performance of the anchor bolt is indirectly evaluated by the size of the relative displacement. In the actual test process, the falling position and direction of the falling hammer need to be controlled to accurately impact the anchor bolt downward. The test operation is difficult, and it is not conducive to efficiently and accurately performing the anchor bolt impact test.

[0044] The present application uses the upward impact to generate acceleration to load the impact load, and formulates the related test standards of the test, which is conducive to efficiently and accurately studying the performance of the anchor bolt under the conditions of crack concrete base material, large edge distance, large spacing, and axial direct impact load. Furthermore, the present application provides beneficial experience for the study of the impact resistance of mechanical anchor bolts. Different from the common test method, the test method of the present application does not need to accurately align the anchor bolt to be tested by the falling hammer to load the impact load. Only the external force is needed to drive the support to rapidly accelerate upward. The instantaneous acceleration of the upward impact combined with the inertial force acceleration of the concrete test block itself realizes the loading of the test impact load for separating the concrete test block and the anchor bolt to be tested, reduces the test operation difficulty, and is conducive to efficiently and accurately performing the anchor bolt impact test.

[0045] The embodiments of the present application also disclose an anchor bolt impact test device. Referring to Figures 1-2 , the anchor bolt impact test device comprises a base 100, a fixed support 200, a lifting platform 1, a movable support 2, a plurality of guide rails 3, and a plurality of impact air cylinders 4. The bottom of the fixed support 200 is fixedly installed on the base 100. The guide rails 3 are vertically arranged and fixed between the top of the base 100 and the fixed support 200. The lifting platform 1 is horizontally arranged and slidably penetrates through the guide rails 3. The movable support 2 is installed on the lifting platform 1. The impact air cylinders 4 are vertically arranged and fixed between the bottom of the base 100 and the lifting platform 1. The top of the movable support 2 is provided with an anchoring seat 5. The concrete test block is suspended and fixed to the bottom of the anchoring seat 5 through a plurality of anchor bolts to be tested. The anchoring seat 5 is further provided with a displacement sensor 300. The plurality of guide rails 3 and the plurality of impact air cylinders 4 are spaced apart and arranged on the periphery of the lifting platform 1. The plurality of impact air cylinders 4 work synchronously and provide the instantaneous acceleration of the upward impact of the lifting platform 1.

[0046] In order to facilitate the detection and recording of the instantaneous acceleration of the lifting platform 1, the instantaneous acceleration and the mass are then used to indirectly calculate the impact load N test,shockA photoelectric gate 9 is installed on one inner side wall of the fixed bracket 200, and a horizontally arranged light-blocking plate 14 is vertically installed on one outer side of the lifting platform 1. The instantaneous acceleration in real time can be calculated by the ratio of the light blocking time to the width when the light-blocking plate 14 passes through the photoelectric gate 9, so that the loading action of the impact cylinder 4 can be stopped after the maximum instantaneous acceleration reaches the preset standard.

[0047] Because the upward impact force generated by the impact cylinder 4 is relatively large, in order to enable the lifting platform 1 to brake and decelerate quickly after generating a sufficiently large upward instantaneous acceleration, multiple pneumatic clamps 6 are installed around the lifting platform 1. The pneumatic clamps 6 are arranged one-to-one with the guide rails 3, and the guide rails 3 slide through the pneumatic clamps 6. Multiple pneumatic clamps 6 work synchronously to quickly brake the lifting platform 1 that is impacting upward at high speed.

[0048] In this embodiment, the photoelectric gate 9, displacement sensor 300, pneumatic clamp 6, and impact cylinder 4 are all electrically connected to and controlled by the device's electrical control system. The automatic control and management of the equipment are achieved through the transmission of electrical signals, while also facilitating the recording and calculation of key parameters and indicators during the test process.

[0049] To facilitate the installation, disassembly, and maintenance of the pneumatic clamp 6, a thickened structure is provided around the perimeter of the lifting platform 1. A cavity 11 is provided on the thickened structure. The pneumatic clamp 6 is fixedly installed in the cavity 11, and the opening of the cavity 11 is sealed by a cover plate 12. The cover plate 12 is located above the pneumatic clamp 6, and it provides good protection for the pneumatic clamp 6 during the impact test. To further reduce the impact damage to the pneumatic clamp 6 and ensure its normal and stable operation, the air inlet of the pneumatic clamp 6 is arranged downwards and extends out of the lower surface of the lifting platform 1.

[0050] Because the upward impact force generated by the impact cylinder 4 is relatively large, in order to prevent the lifting platform 1 from damaging the fixed support 200 after generating a sufficiently large upward instantaneous acceleration, and also to improve the stability of the equipment during the loading impact process, multiple elastic buffer parts 7 are provided on the top of the fixed support 200. The elastic buffer parts 7 are arranged one-to-one with the guide rails 3. The elastic buffer parts 7 are used to flexibly contact the periphery of the lifting platform 1 under high-speed upward impact. Specifically, the elastic buffer part 7 includes a rubber block 71 and multiple sets of buffer bolts 72. The top of the guide rail 3 passes through the rubber block 71, and the rubber block 71 is detachably assembled to the top of the fixed support 200 by the multiple sets of buffer bolts 72. The elastic buffer parts 7 designed above have a simple structure, are easy to install, disassemble, and replace, and have a good impact resistance, providing good protection for the fixed support 200 and the lifting platform 1.

[0051] In this embodiment, to improve the installation stability of the movable support 2, the movable support 2 includes a rectangular top frame 21 and multiple columns 22. At least four columns 22 are vertically connected to the bottom of the four corners of the rectangular top frame 21. Both the rectangular top frame 21 and the columns 22 are made of I-beams. A freely rotatable ball bearing 400 is embedded in the inner top of the fixed support 200, and the ball bearing 400 abuts against the outer wall of the column 22. This structural design not only makes the movable support 2 more stable during high-speed impact lifting, but the added ball bearing 400 design also reduces the resistance of the movable support 2 during lifting, combining stability and smooth lifting.

[0052] In this embodiment, to facilitate the suspension and fixed connection of the concrete test block, the anchoring base 5 includes a horizontally arranged anchoring plate 51 and multiple vertically arranged suspension rods 52. The top of the suspension rods 52 is bolted to the top of the movable bracket 2, and the bottom of the suspension rods 52 is fixed to the anchoring plate 51. The anchoring plate 51 is provided with multiple spaced anchor bolt holes. The anchor bolt to be tested is fixed and vertically passes through the anchor bolt holes. The anchoring plate 51 is also provided with mounting holes. The displacement sensor 300 is fixed in the mounting holes, and the bottom detection surface of the displacement sensor 300 is flush with the lower surface of the anchoring plate 51. After the concrete test block is loaded with an impact load, the concrete test block will generate a certain amount of downward displacement, but the anchoring plate 51 and the anchor bolt to be tested are in a fixed state. The displacement sensor 300 can quickly detect the above displacement value.

[0053] Since the lifting platform 1 needs to be driven to rise, in order to reduce the overall weight of the lifting platform 1, a weight reduction notch 13 is also provided in the middle of the lifting platform 1. The weight reduction notch 13 completely covers the downward projected area of ​​the concrete test block.

[0054] When reinforced concrete members undergo plastic deformation, cracks will form in the area of ​​tensile stress (tension zone). Due to stress concentration, cracks will preferentially pass through the borehole of the anchor bolt under test. Therefore, anchor bolt impact tests are conducted on cracked concrete substrates. For anchor bolt impact tests, it is necessary to machine parallel cracks on the concrete specimen. The test conditions are uniform and do not depend on the anchor bolt's anchorage depth.

[0055] The base 100 is also equipped with a slit-opening mechanism 8, which is used to process parallel cracks on the bottom of the concrete test block. The concrete test block has drilled holes adapted for fixing the anchor bolts to be tested. The width of the parallel cracks is between 0.6-0.8 mm and extends through the bottom of all drilled holes. The design of the weight-reduction notch 13 not only has a certain weight-reduction effect, but also allows some components of the slit-opening mechanism 8 to rise to contact the bottom of the concrete test block through the weight-reduction notch 13 when it is necessary to process parallel cracks on the bottom of the concrete test block. That is, the weight-reduction notch 13 also has a certain effect of avoiding and freeing up space for the processing of parallel cracks.

[0056] In this embodiment, the slit-opening mechanism 8 includes a servo motor-driven linear slide module 81, a lifting cylinder 82, a mounting base 83, a cutting disc 84, and a drive motor 85. The lifting cylinder 82 is arranged vertically and its bottom is mounted on the sliding block of the linear slide module 81. The linear slide module 81 is arranged along the length direction parallel to the crack. The mounting base 83 is fixedly mounted on the top of the telescopic rod of the lifting cylinder 82. The cutting disc 84 is rotatably assembled in the mounting base 83 and is driven to rotate at high speed by the drive motor 85. The cutting disc 84 is arranged vertically and its rotation axis is arranged horizontally. The drive motor 85 is fixedly mounted on one outer side of the mounting base 83.

[0057] Activating the lifting cylinder 82 causes the mounting base 83, cutting disc 84, and drive motor 85 to rise together until the cutting disc 84 and drive motor 85 are above the lifting platform 1, and the cutting disc 84 is lifted to one side of the concrete specimen. Then, the drive motor 85 and linear slide module 81 are activated, which drives the high-speed rotating cutting disc 84 to move linearly, thereby quickly processing parallel cracks on the bottom of the concrete specimen. The crack-opening mechanism 8 designed above has a simple structure, stable operation, and can be precisely controlled by a PLC control module to achieve the purpose of automated processing of parallel cracks with small widths.

[0058] To accommodate concrete test blocks of various sizes and parallel cracks of different depths, the lifting cylinder 82 is an adjustable stroke cylinder. Through precise measurement and setting in the early stage, the cutting disc 84 can be raised to the appropriate position after the lifting cylinder 82 is opened to the limit position, so that the top of the parallel crack can be opened to the bottom of all the drill holes.

[0059] To facilitate direct connection of the drive motor 85 to the drive shaft of the cutting disc 84, eliminating the need for complex structures such as a gearbox, the drive motor 85 is a hydraulic motor.

[0060] The specific test method for the above-mentioned anchor bolt impact test device is as follows:

[0061] Step 1: Drill holes on the upper surface of the concrete test block and clean the holes. Then, attach the concrete test block to the lower surface of the anchor seat 5 and suspend and fix it by multiple anchor bolts to be tested.

[0062] Step 2: Make parallel cracks that run through all the drilled holes at the bottom of the concrete test block. The width of the parallel cracks should be between 0.6-0.8 mm.

[0063] Step 3: Simultaneously activate the impact cylinder 4 and drive the lifting platform 1 to rise rapidly, creating an instantaneous upward impact acceleration. Combined with the downward inertial acceleration of the concrete specimen itself, the impact load N of the loading test is achieved. test,shock ;

[0064] Step 4: All anchors to be tested are subjected to the same impact load N test,shock During the two loading cycles, no operation (such as re-tensioning) is performed on the anchor bolt under test between the two impact loading cycles. test,shock The displacements s1 and s2 of the concrete specimen were measured using displacement sensor 300.

[0065] Step 5: If the impact test evaluation of the anchor bolt meets the following criteria, then the anchor bolt is considered to exhibit good impact resistance in impact-damped and severely cracked concrete substrates:

[0066] The 90th percentile of the displacement s1 under the first loading impact is not greater than 10 mm;

[0067] The standard deviation of the displacement s1 under the first loading impact is no greater than 3mm;

[0068] The expected value of the displacement s1 under the first loading impact is greater than the expected value of the displacement s2 under the second loading impact.

[0069] In any case, the minimum anchor bolt size or borehole diameter is crucial for the impact testing verification of mechanical anchor bolts. Therefore, small-sized anchor bolts are always used in actual testing, based on the design value R of the impact bearing capacity of the concrete specimen. d,shock Anchor bolt impact tests were conducted using concrete blocks of mass m (25kg, 52kg, or 70kg), where the 25kg block dimensions were 290 x 290 x 120mm, the 52kg block dimensions were 360 ​​x 360 x 160mm, and the 70kg block dimensions were 360 ​​x 360 x 210mm. The maximum acceleration a was measured. test,shock As shown in the table below:

[0070] Anchor bolt model BUC / BUC-T BLPE BTP / BTP-X Selected anchor bolt size M10 M8 M8 Impact load design value 20 kN 8.1 kN 3.1 kN Test block mass 70 kg 52 kg 25 kg Acceleration peak ≥29.2g ≥15.9g ≥12.7g

[0071] Among them, the BUC / BUC-T model anchors are self-expanding anchors, the BLPE model anchors are sleeve-type expansion anchors, and the BTP / BTP-X model anchors are wedge-shaped expansion anchors. The working principles of these three common types of anchors on the market are as follows: Figure 3 As shown, attached Figure 3 N in the figure represents the pull-out force borne by the top of the anchor bolt, which is generated by the application of impact load.

[0072] The beneficial technical effects of the anchor bolt impact testing device in this application are roughly as follows:

[0073] For the anchor bolt impact test, the maximum acceleration a is generated using lifting platform 1. test,shockThe impact load is roughly similar to a half-sine wave, with a pulse duration of 20-30ms. The dynamic test load generated by the mass inertia of the concrete specimen also has a half-sine impact waveform. Therefore, the large test impact load that can be rapidly applied to the concrete specimen can be formed by the combined downward inertial force of the concrete specimen and the upward impact force of the lifting platform 1.

[0074] Multiple impact cylinders 4 work synchronously to drive the lifting platform 1 to impact upward and generate instantaneous acceleration. The guide rail 3 has a good guiding and limiting effect on the lifting of the lifting platform 1. At this time, the concrete specimen itself has a downward inertial force acceleration, which is sufficient to quickly load a large test impact load on the concrete specimen in a small space. The whole device occupies little space and operates stably.

[0075] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method of anchor impact testing, characterized by, The method comprises the following steps: The concrete test block is hung on the support through the anchor bolt to be tested, the support is driven to accelerate upward by external force, and the instantaneous acceleration of upward impact combined with the inertial force acceleration of the concrete test block itself realizes the test impact load for separating the concrete test block and the anchor bolt to be tested; A single concrete test block is hung and fixed through multiple anchor bolts to be tested, and the upper surface of the concrete test block is provided with multiple downward arranged drill holes, and a parallel crack penetrating all the drill holes is processed at the bottom of the concrete test block, and the parallel crack width is between 0.6-0.8mm; All the anchor bolts to be tested are subjected to twice loading of the same impact load, no operation is performed on the anchor bolts to be tested between the twice impact loadings, and the displacement s1 and the displacement s2 of the concrete test block are measured by the displacement sensor under the twice impact loadings; if the impact test evaluation of the anchor bolt to be tested meets the following standards, it is considered that the anchor bolt to be tested shows good impact bearing performance on the impact and severely cracked concrete base material: The 90% quantile of the displacement s1 under the first loading impact is not greater than 10mm; The standard deviation of the displacement s1 under the first loading impact is not greater than 3mm; The expected value of the displacement s1 under the first loading impact is greater than the expected value of the displacement s2 under the second loading impact.

2. An anchor impact testing device characterized by, The anchor bolt impact test method of claim 1, the anchor bolt impact test device comprises a base (100), a fixed support (200), a lifting platform (1), a movable support (2), multiple guide rails (3) and multiple impact air cylinders (4), the bottom of the fixed support (200) is fixedly installed on the base (100), the guide rails (3) are vertically arranged and fixed between the base (100) and the top of the fixed support (200), the lifting platform (1) is horizontally arranged and slid through by the guide rails (3), the movable support (2) is installed on the lifting platform (1), the impact air cylinders (4) are vertically arranged and fixed between the base (100) and the bottom of the lifting platform (1), the top of the movable support (2) is provided with an anchoring seat (5), a concrete test block is hung and fixed on the bottom of the anchoring seat (5) through multiple anchor bolts to be tested, the anchoring seat (5) is further provided with a displacement sensor (300), multiple guide rails (3) and multiple impact air cylinders (4) are distributed on the periphery of the lifting platform (1), multiple impact air cylinders (4) work synchronously and are used to provide the instantaneous acceleration of upward impact of the lifting platform (1).

3. The anchor impact testing device of claim 2, wherein, Multiple pneumatic clamps (6) are installed on the periphery of the lifting platform (1), the pneumatic clamps (6) are arranged one by one corresponding to the guide rails (3), the guide rails (3) slide through the pneumatic clamps (6), and multiple pneumatic clamps (6) work synchronously to quickly brake the lifting platform (1) which impacts upward at high speed.

4. The anchor impact testing device of claim 3, wherein, The periphery of the lifting platform (1) is provided with a thickened structure, and a cavity (11) is arranged on the thickened structure, the pneumatic clamp (6) is fixedly installed in the cavity (11), and the opening of the cavity (11) is sealed by a cover plate (12).

5. The anchor impact testing device of claim 2, wherein, The top of the fixed support (200) is further provided with a plurality of elastic buffers (7), the elastic buffers (7) are arranged in one-to-one correspondence with the guide rails (3), and the elastic buffers (7) are used for flexibly contacting the periphery of the lifting platform (1) which is impacted upward at high speed.

6. The anchor impact testing device of claim 5, wherein, The elastic buffer (7) comprises a rubber block (71) and a plurality of groups of buffer bolts (72), the top of the guide rail (3) penetrates through the rubber block (71), and the rubber block (71) is detachably assembled with the top of the fixed support (200) through the plurality of groups of buffer bolts (72).

7. The anchor impact testing device of claim 2, wherein, The movable support (2) comprises a rectangular top frame (21) and a plurality of vertical columns (22), at least four vertical columns (22) are vertically connected to the bottom of four corners of the rectangular top frame (21), and the rectangular top frame (21) and the vertical columns (22) are both made of I-beams.

8. The anchor impact testing device of claim 2, wherein, The anchoring seat (5) comprises a horizontally arranged anchoring plate (51) and a plurality of vertically arranged suspension rods (52), the top of the suspension rod (52) is bolted to the top of the movable support (2), the bottom of the suspension rod (52) is fixed to the anchoring plate (51), a plurality of spaced anchoring holes are arranged on the anchoring plate (51), and the to-be-tested anchor is fixed and vertically penetrates through the anchoring holes, the anchoring plate (51) is further provided with a mounting hole, the displacement sensor (300) is fixed in the mounting hole, and the bottom detection surface of the displacement sensor (300) is flush with the lower surface of the anchoring plate (51).

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