Ice impact loading test device and method

Abstract

The invention relates to the technical field of ice impact tests, and particularly discloses an ice impact loading test device, an impact control module respectively regulates and controls the falling height of a weight-adjustable impact body, a number-adjustable loading rod and an end structure of the loading rod through two control units, the impact body impacts the loading rod to make the loading rod axially contact an ice sample, and the loading rod is loaded into the ice sample. The sample circumferential boundary limiting module can enable the circumferential surface of the ice sample to be in a free or fixed state; the multi-dimensional data acquisition module respectively acquires stress change of a loading rod, acceleration signal change of an ice sample and a crack evolution time sequence image by utilizing a strain gauge, an acceleration sensor and a camera unit, and the quantitative output module calculates key parameters such as a dynamic stress-strain curve and a critical impact load of the ice sample according to the acquired data.

Description

Technical Field

[0001] This invention relates to the field of ice impact testing technology, and specifically to an ice impact loading test apparatus and method. Background Technology

[0002] The mainstream approach for testing the impact characteristics of brittle materials such as ice samples in this field is a free-fall impact device with a heavy hammer. Its core structure is designed as follows: a column or guide frame serves as the main support, with a heavy hammer assembly and release mechanism. The heavy hammer falls freely along a fixed guide rail and acts on the sample in two ways: either the impact load is transmitted through a single fixed-end loading rod, or the sample is directly impacted. The constraint method for the sample is relatively simple, usually placed directly on the surface of a rigid support platform or placed in a cylindrical container of a single specification. The measurement system focuses on acquiring mechanical parameters, mainly relying on a single-channel force sensor (or a force sensor arranged below the support platform) to obtain impact load data. Only in a few scenarios is a single accelerometer or high-speed camera additionally configured for qualitative observation of the sample failure process. A systematic quantitative measurement system has not yet been formed. Summary of the Invention

[0003] The purpose of this invention is to provide an ice impact loading test apparatus and method to solve the technical problems of existing ice impact tests, such as fixed ice impact test loading methods and data measurement, and low detection accuracy.

[0004] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution:

[0005] An ice impact loading test apparatus, comprising:

[0006] Impact control module, including:

[0007] The first control unit is configured to control the adjustable-weight impactor and its drop height;

[0008] The second control unit is configured to control an adjustable number of loading rods and their end structures.

[0009] The first control unit releases the impactor to strike the top of the loading rod, causing the loading rod to contact the end of the ice sample along its axial direction;

[0010] The circumferential boundary constraint module is configured to constrain the circumferential surface of the ice sample.

[0011] The multi-dimensional data acquisition module includes:

[0012] The strain signal acquisition unit is configured to acquire strain signals generated by multiple strain gauges, and the multiple strain gauges are disposed on the rod of the loading rod. The strain gauges generate stress changes during the loading rod being impacted by the impacting body at the top and during the loading rod contacting the ice sample.

[0013] An acceleration acquisition unit is configured to acquire acceleration signals generated by multiple acceleration sensors, and the multiple acceleration sensors are disposed on the surface of the ice sample. The acceleration sensors generate changes in acceleration signals after the ice sample is impacted by the loading rod.

[0014] The camera unit, located circumferentially outside the circumferential boundary limiting module of the sample, is configured to record images of the crack initiation, propagation and fracture process of the ice sample in a time sequence.

[0015] The quantization output module calculates the dynamic stress-strain curve, critical impact load condition, crack network and fragmentation particle size distribution, and energy absorption ratio of the ice sample based on the stress change, acceleration signal change, and image data acquired by the strain signal acquisition unit, acceleration acquisition unit, and camera unit.

[0016] As a preferred embodiment of the present invention, the first control unit includes a release mechanism and a guide mechanism. The release mechanism is configured to clamp and release the impactor, and the guide mechanism is used to guide the path of the impactor after it is released by the release mechanism, so that the impactor contacts the top end of the loading rod along the axial direction of the ice sample.

[0017] As a preferred embodiment of the present invention, the second control unit includes a support platform located directly above the circumferential boundary limiting module of the sample, and a mounting position for vertically mounting the loading rod is provided on the support platform.

[0018] In a preferred embodiment of the present invention, the loading rod comprises a single rod body, the bottom end of which is threadedly connected to an end.

[0019] As a preferred embodiment of the present invention, the loading rod includes a plurality of rods, the top of each rod being connected to the lower surface of a supporting bearing panel, and each rod having an end at its bottom;

[0020] The supporting and bearing panel has a plate-shaped structure corresponding to a regular geometric body. All the rods are centrally symmetrically distributed with the geometric center of the lower surface of the supporting and bearing panel as the center of symmetry. Each of the loading rods is perpendicular to the supporting and bearing panel.

[0021] Wherein, the distance of each of the rods from the center of symmetry is less than the radius of the ice sample.

[0022] As a preferred embodiment of the present invention, the end face shape or overall shape of the end is any one of conical, hemispherical, flat-headed, or spherical.

[0023] As a preferred embodiment of the present invention, the circumferential boundary limiting module of the sample includes a base, a fixing position for installing the ice sample and a sleeve disposed on the fixing position, the sleeve being fitted around the circumferential outside of the ice sample for fixing the ice sample, the sleeve being a hollow cylindrical structure made of transparent tempered glass, and one or multiple reinforcing rings being fitted on the outer wall of the sleeve or evenly fitted along the axial direction of the sleeve.

[0024] The constraint strength of the sleeve on the ice sample when it is subjected to impact is adjusted by the number of reinforcing rings.

[0025] As a preferred embodiment of the present invention, the guiding mechanism includes a cylindrical hollow guiding tube, the two ends of the hollow guiding tube being open and forming a guiding channel for the impactor along its axial direction, the bottom end of the hollow guiding tube being close to the top of the circumferential boundary limiting module of the sample, so that the impactor contacts the top of the ice sample along the axial direction of the ice sample.

[0026] There is a gap between the outer wall of the impactor and the inner wall of the hollow guide tube.

[0027] An ice impact loading test method based on the aforementioned ice impact loading test apparatus includes the following steps:

[0028] Step 100: Based on the diameter and height of the ice sample to be tested, select a suitable circumferential boundary constraint module for the sample and fix the circumferential boundary constraint module on the ground. Then select whether to fix the circumferential direction of the ice sample. The fixing method includes a weak constraint state provided by a transparent thin-walled plastic bucket or a strong constraint state provided by a thick-walled transparent tempered glass.

[0029] Step 200: Based on the target impact energy, adjust the mass of the impactor and adjust the falling height of the impactor using the first control unit, while configuring the distribution of the single or multiple arrays of loading rods and adjusting the spacing between the rods.

[0030] This includes changing the end of the rod to a conical, hemispherical, flat, or rubber ball shape, determining the impact loading path of the impactor acting directly or indirectly on the ice sample through the loading rod, and completing the matching of impact loading parameters.

[0031] Step 300: Attach high-frequency strain gauges to the surface of the loading rod, arrange accelerometers and configure high-speed cameras at different positions on the ice sample; unify the trigger settings of the high-frequency strain gauges, accelerometers and high-speed cameras to achieve synchronous acquisition of multi-dimensional signals;

[0032] Step 400: Release the impactor through the first control unit, allowing the impactor to fall freely from the set height and strike the end of the loading rod or directly strike the ice sample, thus transferring the impact load to the constrained ice sample.

[0033] Step 500: Use high-frequency strain gauges to record the changes in impact stress in real time, collect acceleration data of ice samples through an accelerometer and integrate to calculate velocity and stress in order to capture the propagation law of shock waves, use a high-speed camera to record the crack initiation, propagation and fracture process of ice samples in time, and finally output a complete dynamic response dataset of ice samples through a data acquisition system.

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] The ice impact loading test apparatus provided by this invention offers multi-parameter controllable adjustment of the adjustable impactor, height, and impactor contact end pattern during the ice impact test process. This enables multi-dimensional synchronous monitoring under different loading conditions with the same sample, using strain gauges, cameras, and acceleration sensors. It provides multi-state boundary constraint states of the ice sample, thereby establishing a temporal correspondence between stress, acceleration, and crack evolution, providing quantitative evidence for studying rate-related effects and failure mechanisms. Attached Figure Description

[0036] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of multiple replaceable end structures of the loading rod provided in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the structure of multiple rods arranged on a supporting bearing panel according to an embodiment of the present invention;

[0040] Figure 4 This is a system structure block diagram of the device according to an embodiment of the present invention.

[0041] The labels in the diagram represent the following:

[0042] 10 - Impact control module; 20 - Specimen circumferential boundary constraint module; 30 - Multi-dimensional data acquisition module; 40 - Quantization output module; 50 - Ice specimen;

[0043] 11-First control unit; 12-Second control unit; 121-Support platform; 13-Impact body; 14-Loading rod; 15-Release mechanism; 16-Guide mechanism; 17-Rod body; 18-End; 19-Support bearing panel;

[0044] 21-Base; 22-Sleeve; 23-Reinforcing ring;

[0045] 31-Strain signal acquisition unit; 32-Acceleration acquisition unit; 33-Camera unit; 34-Strain gauge; 35-Acceleration sensor. Detailed Implementation

[0046] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] like Figures 1-4 As shown, the present invention provides an ice impact loading test apparatus, comprising:

[0048] Impact control module 10 includes:

[0049] The first control unit 11 is configured to control the adjustable weight impactor 13 and its falling height, thereby achieving controllable adjustment of the impact energy and specifically executing the release action, which can be manually cut or electrically controlled to improve the repeatability of the test.

[0050] The second control unit 12 is configured to control an adjustable number of loading rods 14 and their end structures.

[0051] The first control unit 11 releases the impactor 13 to strike the top of the loading rod 14, causing the loading rod 14 to contact the end of the ice sample 50 along its axial direction;

[0052] In this embodiment, the impactor 13 can be selected to act directly on the ice sample, or the impact force can be transmitted through the loading rod to achieve different ice sample load loading paths.

[0053] The circumferential boundary constraint module 20 is configured to constrain the circumferential surface of the ice sample 50.

[0054] Multi-dimensional data acquisition module 30, including:

[0055] The strain signal acquisition unit 31 is configured to acquire strain signals generated by multiple strain gauges 34, and the multiple strain gauges 34 are set on the rod body of the loading rod 14. The strain gauges 34 generate stress changes when the loading rod 14 is impacted by the impact body 13 at the top and when the loading rod 14 contacts the ice sample 50.

[0056] The acceleration acquisition unit 32 is configured to acquire acceleration signals generated by multiple acceleration sensors 35, and the multiple acceleration sensors 35 are disposed on the surface of the ice sample 50. The acceleration sensors 35 generate acceleration signal changes after the ice sample 50 is impacted by the loading rod 14.

[0057] The camera unit 33 is located on the circumferential outer side of the sample circumferential boundary restriction module 20 and is configured to record images of the ice sample 50 during the crack initiation, propagation and fracture process in a time sequence.

[0058] The quantization output module 40 calculates the dynamic stress-strain curve, critical impact load condition, crack network and fragmentation particle size distribution, and energy absorption ratio of the ice sample 50 based on the stress change, acceleration signal change, and image data acquired by the strain signal acquisition unit 31, acceleration acquisition unit 32, and camera unit 33.

[0059] The collected experimental data (stress changes, acceleration signal changes, and image data) can be directly input into dynamic models such as finite element method and smoothed particle method (SPH). By comparing indicators such as peak load, rise time, crack propagation rate, and energy dissipation ratio, the dynamic stress-strain curve, critical impact load condition, crack network and fragmentation particle size distribution, and energy absorption ratio of ice sample 50 can be calculated.

[0060] Load monitoring: High-frequency strain gauges are attached to the surface of the loaded member to record the changes in impact stress in real time; Ice sample monitoring: Accelerometers are placed at different locations on the ice sample to calculate velocity and stress through integration and capture the propagation law of shock waves; Crack monitoring: A high-speed camera is configured to record the crack initiation, propagation and fracture process in time sequence; All sensor signals and the high-speed camera are triggered in a unified manner to achieve multi-dimensional synchronous acquisition.

[0061] like Figure 1 As shown, the first control unit 11 includes a release mechanism 15 and a guide mechanism 16. The release mechanism 15 is configured to clamp and release the impactor. Figure 1The release mechanism 15 shown is specifically located where a suspension line is connected to the top middle of the impactor 13, and the impactor is released by manually cutting the suspension line. The guide mechanism 16 is a guide rod or conduit that matches the shape of the impactor 13, and the friction between the conduit or guide rod and the impactor 13 is small enough or negligible. The guide mechanism 16 is used to guide the impactor 13 on its path after being released by the release mechanism 15, so that the impactor contacts the top of the loading rod 14 along the axial direction of the ice sample.

[0062] The second control unit 12 includes a support platform 121, which is located directly above the circumferential boundary restriction module 20 of the sample. A mounting position for a vertically mounted loading rod 14 is provided on the support platform 20. Specifically, it can be a silicone flap (the support platform 121 has an opening for mounting the silicone flap, which penetrates the support platform 121), with a cross-shaped opening in the middle. The loading rod 14 passes through the cross-shaped opening. The frictional contact between the outer wall of the loading rod 14 and the silicone flap keeps the loading rod 14 vertical. When the silicone flap is not under force, the cross-shaped opening closes, forming a complete planar structure.

[0063] The loading rod 14 includes a single rod body 17, with an end cap 18 threaded to the bottom end of the rod body 17.

[0064] The loading rod 14 includes a plurality of rods 17, the top of each rod 17 being connected to the lower surface of a support bearing panel 19, and each rod 17 having an end 18 at its bottom.

[0065] The supporting and bearing panel 19 has a plate-shaped structure corresponding to a regular geometry. All the rods 17 are centrally symmetrically distributed with the geometric center of the lower surface of the supporting and bearing panel 19 as the center of symmetry. Each loading rod 14 is perpendicular to the supporting and bearing panel 19.

[0066] In this design, the distance of each rod 17 from the center of symmetry is less than the radius of the ice sample. This facilitates single-point loading or distributed loading.

[0067] When multiple identical rods 17 act synchronously on the ice sample through the supporting bearing panel 19, the following significant technical effects can be achieved:

[0068] (1) Change from single-point loading to distributed axial loading

[0069] With multiple loading rods symmetrically distributed at the geometric center, multiple impact contact points can be formed on the end face of the ice sample, so that the impact load is distributed on the end face of the sample rather than being loaded at a single concentrated point, thus more realistically simulating the actual working conditions of ice being subjected to multiple points or in-plane impacts in engineering.

[0070] (2) Reduce stress concentration at single points and improve loading stability

[0071] Compared to the highly concentrated stress state generated by a single loading rod, multi-rod collaborative loading can distribute the impact energy, reduce the peak stress at a single point, and avoid the overall failure behavior being masked by premature local failure, which is conducive to obtaining more stable and repeatable impact response data.

[0072] (3) Controllable failure mode and crack evolution path

[0073] Symmetrical loading with multiple rods can induce the formation of multi-source crack initiation points inside the ice sample, promoting the expansion and interaction of the crack network, thereby enabling the control of crack propagation mode, fragmentation morphology and energy dissipation path, which is difficult to achieve with a single loading rod.

[0074] (4) Enhance the scalability of impact loading conditions

[0075] By changing the number of loading rods, their distribution radius, and the spacing between them, different stress wave superposition effects and impact response characteristics can be obtained even with the same rod structure, thereby significantly expanding the applicable working conditions of the device.

[0076] The end face shape or overall shape of end 18 can be any one of the following: conical, hemispherical, flat-headed, or spherical. By changing end 18, the stiffness and contact area of ​​the loading rod can be altered, thereby controlling the characteristics of stress concentration and energy dissipation.

[0077] The circumferential boundary limiting module 20 for the sample includes a base 21, a fixing position for mounting the ice sample 50 and a sleeve 22 set on the fixing position. The sleeve 22 is fitted around the circumferential outside of the ice sample 50 to fix the ice sample 50. The sleeve 22 is a hollow cylindrical structure made of transparent tempered glass. One or multiple reinforcing rings 23 are fitted on the outer wall of the sleeve 22 or evenly fitted along the axial direction of the sleeve 22.

[0078] The constraint strength of the sleeve 22 on the ice sample 50 when it is subjected to impact is adjusted by the number of reinforcing rings 23.

[0079] The guiding mechanism 16 includes a cylindrical hollow guide tube with open ends and forming a guiding channel for the impactor 13 along its axial direction. The bottom end of the hollow guide tube is engaged with the top of the circumferential boundary restriction module 20 of the sample (or close to the top of the circumferential boundary restriction module 20 of the sample), so that the impactor 13 contacts the top of the ice sample 50 along the axial direction of the ice sample 50.

[0080] There is a gap between the outer wall of the impactor 13 and the inner wall of the hollow guide tube, the purpose of which is to minimize the coefficient of friction between the two.

[0081] The circumferential constraint state of the ice sample can be changed by adjusting the following parameters:

[0082] 1. The number of reinforcing rings;

[0083] 2. Axial distribution of the reinforcing rings;

[0084] 3. Reinforce the thickness and width of the ring;

[0085] 4. Spacing between adjacent reinforcing rings.

[0086] The above structure enables the adjustment of circumferential boundary conditions to be completed within the same device system, without the need to replace the base bucket or rearrange the sample, thus forming an integrated and modular boundary constraint adjustment method.

[0087] With fewer reinforcing rings, and smaller thickness and width, the overall stiffness of the base bucket is low, resulting in a weak constraint on the ice sample.

[0088] As the number of reinforcing rings increases or their thickness and width increase, the overall circumferential stiffness of the base barrel gradually increases, thereby forming a stronger circumferential (or radial) constraint on the ice sample.

[0089] Therefore, the strong and weak constraints in this invention are not achieved by changing different containers, but by adjusting the stiffening ring parameters to achieve a continuous or graded circumferential constraint state, and the adjustment method has a clear structural basis.

[0090] In this embodiment, the base 21 provides multiple boundary constraint states: free state, weakly constrained state, and strongly constrained state. Specifically, the weakly constrained state can be achieved through transparent glass sleeves of different thicknesses. Under strong constraint conditions, a buffer layer can be added or a gap can be set to study the influence of different boundary stiffnesses on the failure mode and energy absorption of ice samples.

[0091] In the specific experimental process, the impactor falls freely from a set height under the action of the release mechanism → impacts the end of the loading rod or directly impacts the ice sample → the impact load is transferred to the ice sample → the strain gauge, accelerometer and high-speed camera are synchronously triggered to record the load, acceleration and crack propagation information → the data acquisition system outputs a complete dynamic response dataset. Through this process, the impact load is controllably transferred to the ice sample, and the strain gauge, accelerometer and high-speed camera will record the multi-dimensional response data generated in this process at the same time base.

[0092] The transparent thin-walled plastic buckets provided in this embodiment (e.g., wall thickness t1 = 3–5 mm) and thick-walled transparent buckets with strong constraints (e.g., wall thickness t2 = 10–20 mm) can be configured with buffer linings or gaps (e.g., 1–3 mm). By switching boundary conditions, the influence of boundary stiffness on peak load, crack propagation rate, and failure mode can be systematically quantified.

[0093] This embodiment provides an ice impact loading test method based on the aforementioned ice impact loading test device, comprising the following steps:

[0094] Step 100: Based on the diameter and height of the ice sample to be tested, select a suitable circumferential boundary constraint module for the sample and fix the circumferential boundary constraint module on the ground. Then select whether to fix the circumferential direction of the ice sample. The fixing method includes a weak constraint state provided by a transparent thin-walled plastic bucket or a strong constraint state provided by a thick-walled transparent tempered glass.

[0095] Step 200: Based on the target impact energy, adjust the mass of the impactor and adjust the falling height of the impactor using the first control unit, while configuring the distribution of the single or multiple arrays of loading rods and adjusting the spacing between the rods.

[0096] This includes changing the end of the rod to a conical, hemispherical, flat, or rubber ball shape, determining the impact loading path of the impactor acting directly or indirectly on the ice sample through the loading rod, and completing the matching of impact loading parameters.

[0097] Step 300: Attach high-frequency strain gauges to the surface of the loading rod, arrange accelerometers and configure high-speed cameras at different positions on the ice sample; unify the trigger settings of the high-frequency strain gauges, accelerometers and high-speed cameras to achieve synchronous acquisition of multi-dimensional signals;

[0098] Step 400: Release the impactor through the first control unit, allowing the impactor to fall freely from the set height and strike the end of the loading rod or directly strike the ice sample, thus transferring the impact load to the constrained ice sample.

[0099] Step 500: Use high-frequency strain gauges to record the changes in impact stress in real time, collect acceleration data of ice samples through an accelerometer and integrate to calculate velocity and stress in order to capture the propagation law of shock waves, use a high-speed camera to record the crack initiation, propagation and fracture process of ice samples in time, and finally output a complete dynamic response dataset of ice samples through a data acquisition system.

[0100] In this embodiment, the axial stress of the loading rod during the impact process can be determined by the strain signal measured by the strain gauge according to... After conversion, the energy absorbed by the ice sample can be obtained by integrating the load-displacement relationship.

[0101] 1. Obtaining dynamic stress-strain curves

[0102] During the impact loading process, the axial strain time history signal is obtained by the high-frequency strain gauge 34 set on the surface of the loading rod 14. Based on the material parameters of the loading rod (elastic modulus) ) and cross-sectional area The strain signal can be converted into the time history of the axial stress of the loading rod. For example, it can be represented as:

[0103] ;

[0104] Corresponding impact load It can be represented as:

[0105] ;

[0106] The axial deformation response of the ice sample can be combined with the acceleration signal acquired by the accelerometer 35. The velocity and displacement responses are obtained through time integration, for example:

[0107] ;

[0108] This allows us to correlate the stress and deformation response at different moments during the impact process, thus obtaining the dynamic stress-strain relationship curve of the ice sample.

[0109] 2. Determination of Critical Impact Load Conditions

[0110] The critical impact load can be determined by characteristic points in the load bar stress or load time history, such as the moment when the impact load reaches its peak, or the stress-time curve. The moment when a significant change occurs:

[0111] ;

[0112] Alternatively, the load time history can be correlated with the time point when the ice sample first cracks in the high-speed camera recording, and the impact load at the corresponding time can be determined as the critical impact load.

[0113] 3. Obtaining the crack network and fragment size distribution

[0114] Crack network information is analyzed using time-series images acquired by the high-speed camera unit 33 to record the crack initiation location, propagation path, and penetration morphology.

[0115] After the sample fragments break, statistical analysis can be performed on the fragment size to obtain characteristic parameters of the fragment particle size distribution. This process can be achieved through image processing and statistical methods, which are standard data processing techniques in this field.

[0116] 4. Calculation method of energy absorption ratio

[0117] Impact input energy The mass of the impact body 13 can be determined by and release height Determine, for example:

[0118] ;

[0119] The energy absorbed by the ice sample can be obtained through the load-displacement relationship during the impact process. Perform integral estimation, for example:

[0120] ;

[0121] Energy absorption ratio of ice sample It can be represented as:

[0122] ;

[0123] 5. Collaborative Correspondence of Multi-Source Data

[0124] By synchronously acquiring strain signals, acceleration signals, and high-speed camera images, the mechanical response can be correlated with the crack evolution process on a time scale, thereby improving the reliability of the quantification results.

[0125] The above embodiments are merely exemplary embodiments of this application and are not intended to limit this application. The scope of protection of this application is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to this application within its substance and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of this application.

Claims

1. An ice impact loading test apparatus, characterized in that, include: Impact control module (10), including: The first control unit (11) is configured to control the adjustable weight impactor (13) and its drop height; The second control unit (12) is configured to control an adjustable number of loading rods (14) and their end structures; The first control unit (11) releases the impactor (13) to strike the top of the loading rod (14), causing the loading rod (14) to contact the end of the ice sample (50) along its axial direction; The circumferential boundary constraint module (20) is configured to constrain the circumferential surface of the ice sample (50). The multi-dimensional data acquisition module (30) includes: The strain signal acquisition unit (31) is configured to acquire strain signals generated by multiple strain gauges (34), and the multiple strain gauges (34) are disposed on the rod of the loading rod (14). The strain gauges (34) generate stress changes during the process when the loading rod (14) is impacted by the impactor (13) at the top and when the loading rod (14) contacts the ice sample (50). The acceleration acquisition unit (32) is configured to acquire acceleration signals generated by multiple acceleration sensors (35), and the multiple acceleration sensors (35) are disposed on the surface of the ice sample (50). The acceleration sensors (35) generate acceleration signal changes after the ice sample (50) is impacted by the loading rod (14). The camera unit (33) is located on the circumferential outer side of the sample circumferential boundary limiting module (20) and is configured to record images of the ice sample (50) during the crack initiation, propagation and fracture process in a time sequence. The quantization output module (40) calculates the dynamic stress-strain curve, critical impact load condition, crack network and fragmentation particle size distribution and energy absorption ratio of the ice sample (50) based on the stress change, acceleration signal change and image data obtained by the strain signal acquisition unit (31), acceleration acquisition unit (32) and camera unit (33).

2. The ice impact loading test apparatus according to claim 1, characterized in that, The first control unit (11) includes a release mechanism (15) and a guide mechanism (16). The release mechanism (15) is configured to clamp and release the impactor, and the guide mechanism (16) is used to guide the path of the impactor (13) after it is released by the release mechanism (15) so that the impactor contacts the top of the loading rod (14) along the axial direction of the ice sample.

3. The ice impact loading test apparatus according to claim 2, characterized in that, The second control unit (12) includes a support platform (121) located directly above the circumferential boundary limiting module (20) of the sample, and a mounting position for vertically mounting the loading rod (14) is provided on the support platform (20).

4. The ice impact loading test apparatus according to claim 3, characterized in that, The loading rod (14) includes a single rod body (17), the bottom end of which is threaded with an end cap (18).

5. The ice impact loading test apparatus according to claim 3, characterized in that, The loading rod (14) includes multiple rods, each rod (17) having its top connected to the lower surface of a support bearing panel (19), and each rod (17) having an end (18) at its bottom. The supporting plate (19) has a plate-shaped structure corresponding to a regular geometric body. All the rods (17) are centrally symmetrically distributed with the geometric center of the lower surface of the supporting plate (19) as the center of symmetry. Each loading rod (14) is perpendicular to the supporting plate (19). Wherein, the distance of each of the rods (17) from the center of symmetry is less than the radius of the ice sample.

6. An ice impact loading test apparatus according to claim 4 or 5, characterized in that, The end face shape or overall shape of the end (18) is any one of the following: conical, hemispherical, flat-headed, or spherical.

7. The ice impact loading test apparatus according to claim 1, characterized in that, The circumferential boundary limiting module (20) of the sample includes a base (21), a fixing position for installing the ice sample (50) and a sleeve (22) set on the fixing position. The sleeve (22) is fitted on the circumferential outside of the ice sample (50) to fix the ice sample (50). The sleeve (22) is a hollow cylindrical structure made of transparent tempered glass. One or multiple reinforcing rings (23) are fitted on the outer wall of the sleeve (22) or evenly fitted along the axial direction of the sleeve (22). The constraint strength of the sleeve (22) on the ice sample (50) when subjected to impact is adjusted by the number of reinforcing rings (23).

8. The ice impact loading test apparatus according to claim 2, characterized in that, The guiding mechanism (16) includes a cylindrical hollow guide tube, with both ends of the hollow guide tube open and forming a guiding channel for the impactor (13) along its axial direction. The bottom end of the hollow guide tube is close to the top of the circumferential boundary limiting module (20) of the sample, so that the impactor (13) contacts the top of the ice sample (50) along the axial direction of the ice sample (50). There is a gap between the outer wall of the impactor (13) and the inner wall of the hollow guide tube.

9. An ice impact loading test method based on the ice impact loading test apparatus of claim 1, characterized in that, Includes the following steps: Step 100: Based on the diameter and height of the ice sample to be tested, select a suitable circumferential boundary constraint module for the sample and fix the circumferential boundary constraint module on the ground. Then select whether to fix the circumferential direction of the ice sample. The fixing method includes a weak constraint state provided by a transparent thin-walled plastic bucket or a strong constraint state provided by a thick-walled transparent tempered glass. Step 200: Based on the target impact energy, adjust the mass of the impactor and adjust the falling height of the impactor using the first control unit, while configuring the distribution of the single or multiple arrays of loading rods and adjusting the spacing between the rods. This includes changing the end of the rod to a conical, hemispherical, flat, or rubber ball shape, determining the impact loading path of the impactor acting directly or indirectly on the ice sample through the loading rod, and completing the matching of impact loading parameters. Step 300: Attach high-frequency strain gauges to the surface of the loading rod, arrange accelerometers and configure high-speed cameras at different positions on the ice sample; unify the trigger settings of the high-frequency strain gauges, accelerometers and high-speed cameras to achieve synchronous acquisition of multi-dimensional signals; Step 400: Release the impactor through the first control unit, allowing the impactor to fall freely from the set height and strike the end of the loading rod or directly strike the ice sample, thus transferring the impact load to the constrained ice sample. Step 500: Use high-frequency strain gauges to record the changes in impact stress in real time, collect acceleration data of ice samples through an accelerometer and integrate to calculate velocity and stress in order to capture the propagation law of shock waves, use a high-speed camera to record the crack initiation, propagation and fracture process of ice samples in time, and finally output a complete dynamic response dataset of ice samples through a data acquisition system.

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