CN115479851A - Analysis method and device for impact-explosion time sequence loading experimental data - Google Patents

Analysis method and device for impact-explosion time sequence loading experimental data Download PDF

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CN115479851A
CN115479851A CN202211122745.6A CN202211122745A CN115479851A CN 115479851 A CN115479851 A CN 115479851A CN 202211122745 A CN202211122745 A CN 202211122745A CN 115479851 A CN115479851 A CN 115479851A
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stress
time sequence
brittle
impact
explosion
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徐轩
杨军
陈鹏万
武海军
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Beijing Institute of Technology BIT
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    • G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/30—Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight
    • G01N3/313—Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight generated by explosives
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Abstract

The invention provides an analysis method and a device for impact-explosion time sequence loading experimental data, which comprises the following steps: acquiring experimental data; according to the experimental data, determining a stress-strain curve of the brittle medium rod material under the action of the time sequence forced dynamic load in the impact-explosion experimental process; a propagation attenuation model is established by using experimental data and a stress-strain curve, stress waveform information of a time sequence strong dynamic load after the time sequence strong dynamic load is propagated to the end part of the brittle medium rod with the hollow hole is determined through the propagation attenuation model, and the utilization and dissipation rule of stress wave energy in the dynamic brittle failure process can be analyzed by combining the final crushing form and the inoculation characteristic time criterion of the hollow hole end. The invention can provide a propagation attenuation model for time sequence forced dynamic load stress waveform analysis, so as to reliably analyze the utilization and dissipation rule of the energy of the composite stress wave when dynamic brittle fracture is caused in an impact-explosion time sequence loading experiment on the basis of the propagation attenuation model in the follow-up process.

Description

Analysis method and device for impact-explosion time sequence loading experimental data
Technical Field
The invention relates to the technical field of impact/explosion tests, in particular to an analysis method and device for impact-explosion time sequence loading experimental data.
Background
During penetration, the earth-boring weapon creates a fragmentation zone in the ballistic vicinity and a fracture zone adjacent thereto. At this time, penetration action can form penetration shock waves with low amplitude and long duration in a solid medium, then explosive in the projectile body is detonated, explosion shock waves with high amplitude and short duration are further formed, and the time interval of the two stress waves is delta t. Through the space attenuation and damping attenuation, the stress wave acts on the underground structure, and the pre-disturbance effect of penetration shock waves can influence the damage and destruction effects of subsequent explosion shock waves on rock concrete brittle media and the underground structure, but the prior art is difficult to reliably analyze the damage and destruction rules of the brittle media under the forced dynamic load of the impact-explosion time sequence and cannot well analyze the energy utilization and dissipation rules of the composite stress wave generated in the impact-explosion time sequence loading experiment process.
Disclosure of Invention
In view of this, the present invention provides an analysis method and an apparatus for impact-explosion time sequence loading experiment data, which can provide a propagation attenuation model for analyzing a time sequence strong dynamic load acting rule, so as to reliably analyze a dissipation rule of utilization of composite stress wave energy in a dynamic brittle failure time after a time sequence strong dynamic load generated in an impact-explosion experiment process propagates to an end of a brittle medium rod with a hollow hole on the basis of the propagation attenuation model.
In a first aspect, an embodiment of the present invention provides a method for analyzing shock-explosion timing sequence loading experimental data, including: acquiring experimental data; wherein the experimental data is generated in the process of carrying out the impact-explosion experiment in the impact-explosion time sequence loading experimental device; according to the experimental data, determining a stress-strain curve of the brittle medium rod material under the time sequence forced loading in the impact-explosion experimental process; and establishing a propagation attenuation model of the time sequence forced dynamic load in the brittle medium by using the experimental data and the stress-strain curve, and determining a utilization dissipation rule of the composite stress wave energy in the dynamic brittle fracture process after the time sequence forced dynamic load is propagated to the end part of the brittle medium rod with the hollow hole through the propagation attenuation model.
In one embodiment, the impact-explosion time sequence loading experimental device is provided with a brittle medium rod, the brittle medium rod is used for transmitting a composite stress wave caused by impact-explosion time sequence loading, the brittle medium rod is provided with a speckle region, and the experimental data comprises speckle region deformation image data; according to the experimental data, the axial displacement field distribution and the axial velocity field distribution of mass points on the surface of the mass rod are obtained; determining an axial strain time course curve of the brittle medium rod caused by a time sequence strong dynamic load generated in the impact-explosion experimental process according to the axial displacement field distribution and a stress wave mass conservation equation under a Lagrange coordinate system; determining the axial stress time-course curve of the brittle medium rod caused by the time sequence dynamic load generated in the impact-explosion experiment process according to the axial displacement field distribution, the stress fluctuation conservation equation under the Lagrange coordinate system and the path line method integral; and obtaining a stress-strain curve of the brittle medium material under the time sequence dynamic load based on the strain time course curve and the stress time course curve.
In one embodiment, the step of determining the axial displacement field distribution and the axial velocity field distribution of the particles on the surface of the brittle medium rod based on the speckle region deformation image comprises: and utilizing DIC technology to carry out image analysis processing on the speckle region deformation image data, and determining the axial displacement field distribution and the axial velocity field distribution of the surface particles of the brittle medium rod under the time sequence dynamic load.
In one embodiment, the brittle media bar is provided with a super-dynamic strain gage, the experimental data including strain gage measurements; the establishing of the propagation attenuation model of the time sequence forced loading in the brittle medium based on the experimental data and the stress-strain curve comprises the following steps: extracting waveform time-frequency characteristics of the measurement result of the ultra-dynamic strain gauge; determining the change data of the time-frequency characteristics of the waveform of the composite stress wave according to the propagation distance of the time sequence dynamic load; wherein the change data comprises one or more of propagation velocity, transflectance coefficient, spectral characteristics, band energy, and fractal characteristics; and establishing a time sequence forced dynamic load propagation attenuation model based on the damping attenuation parameters of the brittle medium rod, the change data and the stress-strain curve.
In one embodiment, the impact-explosion time sequence loading experimental device is provided with a brittle medium rod, and one end of the brittle medium rod is provided with a hollow hole to be crushed; the method comprises the following steps of determining a utilization dissipation rule of composite stress wave energy when dynamic brittle fracture is caused after the time sequence forced dynamic load is transmitted to the end part of the brittle medium rod with the hollow hole through the propagation attenuation model, wherein the utilization dissipation rule comprises the following steps: calculating stress time-course information acting on the hollow hole to be crushed through the propagation attenuation model; acquiring a hole fracture image corresponding to the hole to be fractured, and determining effective stress wave energy required in the fracture process of the hole to be fractured based on the hole fracture image; based on the effective stress wave energy for brittle fracture, utilizing a breeding characteristic time criterion to perform energy utilization analysis on the stress time-course information, wherein the stress time-course information is obtained through the propagation attenuation model, and is the stress time-course information in the brittle medium after the time sequence strong dynamic load is propagated to the end part of the brittle medium rod with the hollow hole, so that the distribution and the proportion rule of the stress wave energy consumed by dynamic brittle fracture in a composite stress waveform time domain and a frequency domain are further obtained; wherein, the utilization dissipation rule comprises a distribution rule and a proportion rule.
In a second aspect, an embodiment of the present invention further provides an apparatus for analyzing shock-explosion timing sequence loading experimental data, including: the data acquisition module is used for acquiring experimental data; wherein the experimental data is generated in the process of carrying out the impact-explosion experiment in the impact-explosion time sequence loading experimental device; the material mechanical property determining module is used for determining a stress-strain curve of the brittle medium rod material under the time sequence forced load in the impact-explosion experiment process according to the experiment data; and the rule determining module is used for establishing a propagation attenuation model of the time sequence strong dynamic load in the brittle medium by using the experimental data and the stress-strain curve, and determining a utilization dissipation rule of the composite stress wave energy when dynamic brittle fracture occurs after the time sequence strong dynamic load is propagated to the end part of the brittle medium rod with the hollow hole through the propagation attenuation model.
In one embodiment, the impact-explosion time sequence loading experimental device is provided with a brittle medium rod, the brittle medium rod is used for transmitting a composite stress wave caused by impact-explosion time sequence loading, the brittle medium rod is provided with a speckle region, and the experimental data comprises speckle region deformation image data; the material mechanical property determination module is further configured to: determining the axial displacement field distribution and the axial velocity field distribution of the surface particles of the brittle medium rod based on the speckle region deformation image; according to the distribution of the axial displacement field and a mass conservation equation of the stress wave under a Lagrange coordinate system, determining a strain time course curve of the brittle medium under the action of the time sequence strong dynamic load generated in the impact-explosion experiment process; determining a stress time-course curve of the brittle medium under the action of the time sequence forced dynamic load generated in the impact-explosion experimental process according to the axial displacement field distribution, the stress fluctuation conservation equation under the Lagrange coordinate system and the path line method integral; and obtaining a stress-strain curve of the brittle medium material under the time sequence dynamic load based on the strain time course curve and the stress time course curve.
In one embodiment, the material mechanical property determination module is further configured to include: and utilizing DIC (Digital Image Correlation) technology to perform Image analysis processing on the deformation Image data of the speckle region, and determining the axial displacement field distribution and the axial velocity field distribution of the particles on the surface of the brittle medium rod under the time sequence forced loading.
In a third aspect, an embodiment of the present invention further provides an electronic device, including a processor and a memory, where the memory stores computer-executable instructions that can be executed by the processor, and the processor executes the computer-executable instructions to implement any one of the methods provided in the first aspect.
In a fourth aspect, embodiments of the present invention also provide a computer-readable storage medium storing computer-executable instructions that, when invoked and executed by a processor, cause the processor to implement any one of the methods provided in the first aspect.
The method and the device for analyzing the impact-explosion time sequence loading experimental data provided by the embodiment of the invention are characterized in that the experimental data are firstly obtained and generated in the process of carrying out an impact-explosion experiment in an impact-explosion time sequence loading experimental device, then a stress-strain curve of a brittle medium rod material under the action of time sequence strong dynamic load in the impact-explosion experimental process is determined according to the experimental data, finally a time sequence strong dynamic load propagation attenuation model is established based on the experimental data and the stress-strain curve, and the propagation attenuation model is used for determining the utilization and dissipation rule of the composite stress wave energy in the dynamic brittle fracture process after the time sequence strong dynamic load is propagated to the end part of the brittle medium rod with the hollow hole. The method can obtain the experimental data generated in the process of carrying out the impact-explosion experiment in the impact-explosion time sequence loading experimental device, and determines the corresponding stress time-course curve based on the experimental data, so as to obtain the propagation attenuation model for analyzing the time sequence Jiang Dongzai stress waveform, and to be convenient for reliably analyzing the utilization dissipation rule of the energy of the composite stress wave when the composite stress wave generated in the impact-explosion experimental process causes dynamic brittle failure on the basis of the propagation attenuation model.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
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In order 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 described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a schematic flow chart of a method for analyzing shock-explosion time sequence loading experimental data according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of an impact-explosion timing sequence loading experimental apparatus according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of an apparatus for analyzing shock-explosion timing sequence loading experimental data according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.
Icon: 1-laser velocimeter; 2-impact-explosion time sequence loading bin; 3.1-impact block; 3.2-impact block; 4-an explosive; 5-a stopper; 6-detonator; 7-loading bin loading holes; 8-waveform shaper; 9-brittle medium rod loading hole; 10-a brittle media rod; 11-speckle-dispersing area; 12-LED direct current light source; 13-a high-speed camera; 14-ultra dynamic strain gauge; 15-holes to be crushed; 16-a stress absorber; 100-an electronic device; 40-a processor; 41-a memory; 42-a bus; 43-communication interface.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the embodiments, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
At present, the deformation failure rule of the brittle medium under the impact-explosion time sequence dynamic load is difficult to be reliably analyzed in a quantitative mode in the prior art, and based on the analysis, the invention provides a propagation attenuation model for time sequence dynamic load stress waveform analysis, so that the energy utilization dissipation rule of the composite stress wave generated in the impact-explosion experimental process is reliably analyzed on the basis of the propagation attenuation model.
To facilitate understanding of the present embodiment, first, a detailed description is given of an analysis method for shock-explosion time sequence loading experimental data disclosed in the present embodiment, referring to a schematic flow chart of the analysis method for shock-explosion time sequence loading experimental data shown in fig. 1, where the method mainly includes the following steps S102 to S106:
step S102, acquiring experimental data. The experimental data is generated in the process of carrying out the impact-explosion experiment in the impact-explosion time sequence loading experimental device, and can comprise speckle region deformation image data and a super-dynamic strain gauge measurement result. In practical application, a brittle medium rod is arranged in the impact-explosion time sequence loading experimental device, the brittle medium rod is used for transmitting composite stress waves caused by impact-explosion time sequence loading, and the brittle medium rod is provided with a speckle region and a super-dynamic strain gauge, so that an image at the speckle region can be collected through image collection equipment (such as a high-speed camera), the image is speckle region deformation image data, and in addition, the measurement result of the super-dynamic strain gauge can be directly read.
And step S104, determining a stress-strain curve of the brittle medium rod material under the forced time sequence load in the impact-explosion experimental process according to the experimental data. The stress-strain curve is used for representing the mapping relation between stress and strain under the condition of brittle medium dynamic loading. In one embodiment, the speckle region deformation image data in the experimental data may be processed to determine the axial displacement field distribution and the axial velocity field distribution of the brittle medium rod surface particles represented by the speckle region deformation image data, so as to determine a strain time course curve and a stress time course curve respectively based on the axial displacement field distribution and the axial velocity field distribution, and finally obtain a stress-strain curve based on the strain time course curve and the stress time course curve. The strain time course curve can be compared with the test result of the ultra-dynamic strain gauge to check the accuracy of the strain time course curve.
And S106, establishing a time sequence forced dynamic load propagation attenuation model based on the experimental data and the stress-strain curve, and determining a utilization dissipation rule of the energy of the composite stress wave when the composite stress wave is dynamically brittle failure caused after the composite stress wave is propagated to the end part of the brittle medium rod with the hollow hole through the propagation attenuation model. In an implementation mode, a propagation attenuation model can be established based on a measurement result of a hyper-dynamic strain gauge and a stress-strain curve in experimental data, wherein the propagation attenuation model can estimate a stress waveform acting on (entering) a hole to be crushed, and further analyze and obtain a composite stress waveform time-frequency distribution characteristic through time-frequency analysis, and in addition, screening and statistical size distribution are carried out on the hole part fragments, so that final effective energy for dynamic brittle fracture can be obtained, and based on the final effective energy and dissipation rule (stress wave energy utilization dissipation rule for short) of composite stress wave band energy caused by time sequence strong dynamic load of dynamic fracture can be further analyzed.
The analysis method for the impact-explosion time sequence loading experimental data provided by the embodiment of the invention can obtain the experimental data generated in the process of performing the impact-explosion experiment in the impact-explosion time sequence loading experimental device, and determine the corresponding stress time-course curve based on the experimental data, so as to obtain the propagation attenuation model for analyzing the stress waveform of the time sequence Jiang Dongzai, so that the subsequent analysis on the dissipation rule of the composite stress wave energy of the composite stress wave generated in the impact-explosion experimental process in the medium dynamic brittle failure process can be reliably performed on the basis of the propagation attenuation model.
In order to facilitate understanding of the foregoing embodiments, an exemplary shock-explosion time sequence loading experimental apparatus is provided in the embodiments of the present invention, and referring to a schematic structural diagram of a shock-explosion time sequence loading experimental apparatus shown in fig. 2, the shock-explosion time sequence loading experimental apparatus includes a laser velocimeter 1, a shock-explosion time sequence loading bin 2, a strike block 3.1, a strike block 3.2, an explosive 4, a stopper 5, a detonator 6, a loading bin charge hole 7, a wave shaper 8, a brittle medium rod charge hole 9, a brittle medium rod 10, a speckle region 11, an LED (light-emitting diode) dc light source 12, a high-speed camera 13, an ultra-dynamic strain gauge 14, a hole to be crushed 15, and a stress absorber 16.
In practical application, the hollow hole formed by splicing the impact block 3.1 and the impact block 3.2 in the impact-explosion time sequence loading bin 2 and the brittle medium rod charging hole 9 at the left end of the brittle medium rod 10 are filled with explosives 4 serving as load sources, and the explosives are detonated through the hole outside, namely the detonator 6 in the charging hole 7 of the impact-explosion time sequence loading bin 2. Firstly, detonating explosive in the spliced impact block, driving the impact block 3.2 to collide with the left end of the brittle medium rod 10, at the moment, according to momentum conservation, the impact block 3.1 flies out from the left end of the impact-explosion time sequence loading bin 2 at the same speed, and measuring the movement speed of the impact block by using the laser velocimeter 1. Since the impact mass density is much greater than the brittle media, and its velocity is not 0 after impact, a continuous shock pulse is generated at the end of the brittle media rod 10 and the waveform shaper 8 makes the shock pulse smoother. After the impact pulse enters the brittle medium rod 10, the explosive in the explosive loading hole 9 of the brittle medium rod is detonated, and the explosion pulse is formed in the brittle medium rod 10. The two stress pulses are gradually stabilized and transmitted to the right end in the brittle medium rod 10, the transmission and attenuation processes can be jointly recorded by matching the high-speed camera 13 with the LED direct-current light source 12 and the ultra-dynamic strain gauge 14, and the combined action of the two continuous stress pulses can cause the deformation and brittle failure of the hollow hole 15 to be broken. The residual stress wave propagates to the right end of the brittle medium rod 10, and the influence of the residual stress wave on the cavity is rapidly reduced due to the existence of the spatial attenuation in the stress absorber 16 made of the same brittle medium.
On the basis of the foregoing device, an embodiment of the present invention provides an implementation manner for determining a stress-strain curve of a brittle medium material under a time-series forced dynamic load during an impact-explosion experiment according to experimental data, which is shown in the following steps 1 to 4:
step 1, determining the axial displacement field distribution and the axial velocity field distribution of the surface particles of the brittle medium rod based on the speckle region deformation image. In one embodiment, DIC (Digital Image Correlation) technology can be used for Image analysis processing of the speckle region deformation Image data, and axial displacement field distribution and axial velocity field distribution of particles on the surface of the brittle medium rod under the time sequence forced loading are determined. In practical application, DIC technology can be used for analyzing the propagation process of the time sequence forced loading captured by the high-speed camera in the speckle scattering area, so that axial displacement field distribution and axial velocity field distribution caused by stress wave propagation in the brittle medium rod are obtained, and optionally, the axial displacement field distribution and the axial velocity field distribution can be embodied in a cloud picture form.
And 2, determining a strain time course curve corresponding to the time sequence strong dynamic load disturbance of the brittle medium generated in the impact-explosion experimental process according to the distribution of the axial displacement field and a stress wave mass conservation equation under a Lagrange coordinate system. Under the Lagrange coordinate system, the mass conservation equation of the one-dimensional stress wave is described as follows:
Figure BDA0003847099880000091
where v is the particle velocity, ε is the strain, X is the Lagrangian coordinate position, and t is the time. In practical application, particle velocity waveforms v (X) at different X positions are obtained by DIC technology analysis i And t) after the first-order partial derivative of the lagrange coordinate position X is obtained
Figure BDA0003847099880000092
From which it can be obtained from the conservation of mass equation
Figure BDA0003847099880000093
Then, the initial condition of zero time [ t =0, epsilon (X) is utilized i ，0)＝0]Integrating the time t to obtain the strain time course curve epsilon (X) of each position i ，t)。
And 3, determining a corresponding stress time course curve generated in the impact-explosion experimental process when the brittle medium is disturbed by the time sequence dynamic load according to the axial displacement field distribution, the stress fluctuation amount conservation equation under the Lagrange coordinate system and the path line method integral. Under the Lagrange coordinate system, the momentum conservation equation of the one-dimensional stress wave is described as follows:
Figure BDA0003847099880000101
where σ is the stress and ρ is the density. In practical application, the momentum is further conserved in the equation
Figure BDA0003847099880000102
Is converted into
Figure BDA0003847099880000103
The fully differential relationship of the stress along path line P at this time is as follows:
Figure BDA0003847099880000104
substituting the mass conservation equation into the full differential relation of the stress along the path line P to obtain the following formula:
Figure BDA0003847099880000105
on the basis, the initial condition [ t =0, sigma = (d sigma/dX) & ltzero time & gt is satisfied on the first path P1 ＝0]Determining on a path line P at time zero
Figure BDA0003847099880000106
And determining the stress sigma on the next path line by numerical integration, and obtaining stress time-course curves sigma (X) on different Lagrangian positions X by successive analogy according to the obtained formula i ，t)。
In the embodiment of the invention, the strain time course curve and the stress time course curve are respectively obtained by means of a Lagrange's inverse analysis method, a one-dimensional stress wave propagation theory (comprising the mass conservation equation and the momentum conservation equation) and a full differential relation of stress along a path line P.
And 4, obtaining a stress-strain curve of the brittle medium material under the time sequence dynamic load based on the strain time course curve and the stress time course curve. In an embodiment, the strain time-course curve can be used for comparing test results of the ultra-dynamic strain gauge, and a stress-strain curve of the brittle medium under the action of time sequence strong dynamic load disturbance can be obtained by eliminating time parameters in the strain time-course curve and the stress time-course curve.
On the basis of the foregoing device, an embodiment of the present invention provides an implementation manner for establishing a propagation attenuation model based on experimental data and a stress-strain curve, specifically:
(1) And extracting the waveform of the stress time-course curve to perform time-frequency characteristics. In one embodiment, time-frequency characteristic analysis may be performed on the strain gauge measurement results by using algorithms such as short-time fourier transform, continuous wavelet transform, hilbert yellow transform, or the like, to obtain waveform time-frequency characteristics.
(2) And determining the change data of the time-frequency characteristics of the composite stress waveform according to the propagation distance of the time sequence dynamic load. Wherein the change data includes one or more of propagation velocity, transflectance coefficient, spectral characteristics, band energy, and fractal characteristics. In one embodiment, the change rule of the waveform time-frequency information along with the propagation distance (i.e., the change data) can be obtained according to the propagation velocity of the stress wave at different measuring points, the transflective coefficient, the spectral characteristic, the frequency band energy and the fractal characteristic.
(3) And establishing a propagation attenuation model based on the damping attenuation parameters, the change data and the stress-strain curve of the brittle medium rod. In one embodiment, a propagation attenuation model of the time sequence forced dynamic load can be obtained by fitting based on a classical one-dimensional wave equation, considering the damping attenuation effect of the brittle medium and combining the stress-strain curve of the brittle medium under the time sequence forced dynamic load, and the propagation attenuation model is as follows:
Figure BDA0003847099880000111
where ρ is density, u is displacement, t is time, E is elastic modulus, and η is damping coefficient.
On the basis of the analysis method of the impact-explosion time sequence loading experiment data provided by the foregoing embodiment, the embodiment of the present invention further provides an implementation manner of determining a corresponding energy utilization dissipation law when dynamic brittle fracture is caused after the time sequence forced load is transmitted to the end portion of the brittle medium rod with the hollow hole through the propagation attenuation model, specifically, the impact-explosion time sequence loading experiment apparatus provided by the foregoing embodiment is provided with the brittle medium rod, one end of the brittle medium rod is provided with the hollow hole to be fractured, and on this basis, please refer to the following steps a to d:
step a, calculating stress time-course information acting on the hollow hole to be crushed through a propagation attenuation model. Optionally, time-course information of the stress waveform entering or acting on the hollow hole region to be crushed can be obtained through calculation of the propagation attenuation model.
And b, acquiring a hole fracture image corresponding to the hole to be fractured. In one embodiment, the progressive damage process of the to-be-crushed hollow hole at the right end of the brittle medium rod can be captured by a high-speed camera, and a hollow hole fracture image can be obtained.
And c, determining effective fracture energy in the fracture process of the to-be-fractured hollow hole based on the hollow hole fracture image. In one embodiment, the cracked fragments may be collected, and the brittle medium fragments may be subjected to size and mass statistics according to ISO (the International Organization for Standardization) 3310 or ASTM (American Society for Testing and Materials International) E11 by selecting a series of standard sieves with appropriate mesh numbers, and the stress-strain curve of the incident wave at the left end of the blank hole to be cracked may be obtained by combining the time-series strong dynamic load propagation attenuation model provided in the foregoing examples, and the influence rule of the composite stress wave induced by different impact-explosion loading time series on the dynamic brittle fracture may be obtained. And obtaining effective stress wave energy consumed by dynamic brittle fracture according to newly added fracture surfaces of the fragments.
And d, based on the effective stress wave energy for brittle fracture, utilizing the inoculation characteristic time criterion to perform energy utilization analysis on the stress time course information to obtain the distribution and proportion rule of the composite stress wave time domain and frequency domain caused by the dynamic brittle fracture energy after the time sequence strong dynamic load is transmitted to the end part of the brittle medium rod with the hollow hole. The inoculation Characteristic Time criterion (ICT, criterion) is as follows:
Figure BDA0003847099880000121
wherein, F * Is a dimensionless dynamic brittle fracture criterion function, t is time, tau is inoculation characteristic time, sigma 0 Quasi-static intensity, σ (t') is equal to σ 0 Corresponding equivalent stress history.
In one embodiment, the inoculation characteristic time criterion can be further utilized, and the utilization and dissipation rules of the dynamic brittle fracture on the waveform frequency band energy are researched by considering the time-frequency characteristics of the composite stress history waveform, so that the energy utilization characteristics of the time sequence strong dynamic load under different loading intervals can be obtained.
In summary, the method for analyzing the impact-explosion timing sequence loading experimental data provided by the embodiment of the invention at least has the following characteristics: (1) Axial displacement and a velocity field on the brittle medium rod can be obtained by matching with a digital image processing technology (DIC), a Lagrange's inverse analysis method is adopted to process velocity field data, and a stress-strain relation of a stress time-course curve, a strain time-course curve and the brittle medium under time sequence loading can be respectively obtained, wherein the strain time-course curve can be further compared and verified with a test result of the ultra-dynamic strain gauge, and the reliability of test data can be ensured; in addition, a propagation and attenuation model of the composite stress wave under impact-explosion time sequence coupling loading can be established by performing time-frequency analysis on the stress time sequence curve, combining the stress-strain relation of the brittle medium under time sequence loading and based on a mass conservation equation and a momentum conservation equation of the one-dimensional stress wave; (2) The high-speed camera monitors and captures the progressive failure process of the hollow hole to be broken, collected fragments are screened according to ISO 3310 or ASTM E11, effective energy for dynamic brittle fracture in the breaking process can be obtained, stress time course information acting on the hollow hole area to be broken is obtained through calculation according to a stress wave propagation attenuation model, and the influence rule of waveform time-frequency characteristics on dynamic brittle fracture can be obtained through analyzing an input stress course by utilizing a breeding characteristic time criterion.
For the analysis method of the impact-explosion time sequence loading experimental data provided in the foregoing embodiment, an embodiment of the present invention further provides an analysis apparatus of the impact-explosion time sequence loading experimental data, referring to a schematic structural diagram of the analysis apparatus of the impact-explosion time sequence loading experimental data shown in fig. 3, the apparatus mainly includes the following components:
a data acquisition module 302, configured to acquire experimental data; wherein the experimental data is generated in the process of carrying out the impact-explosion experiment in the impact-explosion time sequence loading experimental device;
the material mechanical property determining module 304 is configured to determine a stress-strain curve of the brittle medium rod material under the time-sequence forced load in the impact-explosion experiment process according to the experiment data;
and the rule determining module 306 is used for establishing a propagation attenuation model of the time sequence strong dynamic load in the brittle medium by using the experimental data and the stress-strain curve, and determining a utilization dissipation rule of the composite stress wave energy in the dynamic brittle fracture process after the time sequence strong dynamic load is propagated to the end part of the brittle medium rod with the hollow hole through the propagation attenuation model.
The analysis device for the impact-explosion time sequence loading experimental data provided by the embodiment of the invention can acquire the experimental data generated in the process of performing the impact-explosion experiment in the impact-explosion time sequence loading experimental device, and determine the corresponding stress time-course curve based on the experimental data, so as to obtain a propagation attenuation model for analyzing the attenuation rule of the stress wave, and reliably analyze the energy utilization dissipation rule of the composite stress wave generated in the impact-explosion experimental process on the basis of the propagation attenuation model.
In one embodiment, the impact-explosion time sequence loading experimental device is provided with a brittle medium rod, the brittle medium rod is used for transmitting a composite stress wave caused by impact-explosion time sequence loading, the brittle medium rod is provided with a speckle region, and experimental data comprises speckle region deformation image data; the material mechanical property determination module 304 is further configured to: determining the axial displacement field distribution and the axial velocity field distribution of the surface particles of the brittle medium rod based on the speckle region deformation image; determining the axial strain time course curve of the brittle medium rod caused by the time sequence strong dynamic load generated in the impact-explosion experimental process according to the distribution of the axial displacement field and the mass conservation equation of the stress wave under the Lagrange coordinate system; determining a corresponding stress time-course curve when the brittle medium deforms due to the time sequence strong dynamic load generated in the impact-explosion experiment process according to the distribution of the axial displacement field, the stress fluctuation conservation equation under the Lagrange coordinate system and the path line method integral; and obtaining a stress-strain curve of the brittle medium material under the time sequence strong dynamic load based on the strain time course curve and the stress time course curve.
In one embodiment, the material mechanical property determination module 304 is further configured to: and utilizing DIC technology to carry out image analysis processing on the speckle region deformation image data, and determining the axial displacement field distribution and the axial velocity field distribution of the surface particles of the brittle medium rod under the time sequence forced loading.
In one embodiment, the brittle medium rod is provided with a super dynamic strain gauge, and the experimental data comprises strain gauge measurement results; law determination module 306 is also to: extracting waveform time-frequency characteristics of a measurement result of the ultra-dynamic strain gauge; determining the change data of the time-frequency characteristics of the composite stress waveform according to the propagation distance of the impact-explosion dynamic load; wherein the change data comprises one or more of propagation speed, transflectance coefficient, spectral characteristics, band energy and fractal characteristics; and establishing a time sequence strong dynamic load propagation attenuation model based on the damping attenuation parameters, the change data and the stress-strain curve of the brittle medium rod.
In one embodiment, the impact-explosion time sequence loading experimental device is provided with a brittle medium rod, and one end of the brittle medium rod is provided with a hollow hole to be crushed; law determination module 306 is also to: calculating stress time-course information acting on the empty hole to be crushed through a time-sequence strong dynamic load propagation attenuation model; acquiring a hole fracture image corresponding to a hole to be crushed; determining the effective stress wave energy consumed in the fracture process of the hollow hole to be crushed based on the image of the fracture process of the hollow hole and in combination with the screening result of the fragile medium fragments; based on the effective stress wave energy for brittle fracture, utilizing the inoculation characteristic time criterion to perform energy utilization analysis on stress time-course information, wherein the stress time-course information is obtained through a propagation attenuation model, and is the stress time-course information in the brittle medium after a time sequence forced load is propagated to the end part of the brittle medium rod with the hollow hole, so that the distribution and the proportion rule of the stress wave energy consumed by dynamic brittle fracture in a composite stress waveform time domain and a composite stress waveform frequency domain are obtained; wherein, the dissipation rule comprises a distribution rule and a proportion rule.
The device provided by the embodiment of the present invention has the same implementation principle and technical effect as the method embodiments, and for the sake of brief description, reference may be made to the corresponding contents in the method embodiments without reference to the device embodiments.
The embodiment of the invention provides electronic equipment, which particularly comprises a processor and a storage device; the storage means has stored thereon a computer program which, when executed by the processor, performs the method of any of the above described embodiments.
Fig. 4 is a schematic structural diagram of an electronic device 100 according to an embodiment of the present invention, where the electronic device 100 includes: a processor 40, a memory 41, a bus 42 and a communication interface 43, wherein the processor 40, the communication interface 43 and the memory 41 are connected through the bus 42; the processor 40 is adapted to execute executable modules, such as computer programs, stored in the memory 41.
The Memory 41 may include a high-speed Random Access Memory (RAM) and may also include a non-volatile Memory (non-volatile Memory), such as at least one disk Memory. The communication connection between the network element of the system and at least one other network element is realized through at least one communication interface 43 (which may be wired or wireless), and the internet, a wide area network, a local network, a metropolitan area network, etc. may be used.
The bus 42 may be an ISA bus, PCI bus, EISA bus, or the like. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, only one double-headed arrow is shown in FIG. 4, but that does not indicate only one bus or one type of bus.
The memory 41 is used for storing a program, the processor 40 executes the program after receiving an execution instruction, and the method executed by the apparatus defined by the flow process disclosed in any of the foregoing embodiments of the present invention may be applied to the processor 40, or implemented by the processor 40.
The processor 40 may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the above method may be performed by integrated logic circuits of hardware or instructions in the form of software in the processor 40. The Processor 40 may be a general-purpose Processor, and includes a Central Processing Unit (CPU), a Network Processor (NP), and the like; the device can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other Programmable logic devices, discrete Gate or transistor logic devices, discrete hardware components. The various methods, steps and logic blocks disclosed in the embodiments of the present invention may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software modules may be located in ram, flash, rom, prom, or eprom, registers, etc. as is well known in the art. The storage medium is located in a memory 41, and the processor 40 reads the information in the memory 41 and completes the steps of the method in combination with the hardware thereof.
The computer program product of the readable storage medium provided in the embodiment of the present invention includes a computer readable storage medium storing a program code, where instructions included in the program code may be used to execute the method described in the foregoing method embodiment, and specific implementation may refer to the foregoing method embodiment, which is not described herein again.
The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk, and various media capable of storing program codes.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the following descriptions are only illustrative and not restrictive, and that the scope of the present invention is not limited to the above embodiments: any person skilled in the art can modify or easily conceive the technical solutions described in the foregoing embodiments or equivalent substitutes for some technical features within the technical scope of the present disclosure; such modifications, changes or substitutions do not depart from the spirit and scope of the embodiments of the present invention, and they should be construed as being included therein. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (10)

1. A method for analyzing impact-explosion time sequence loading experiment data is characterized by comprising the following steps:
acquiring experimental data; wherein the experimental data is generated in the process of carrying out the impact-explosion experiment in the impact-explosion time sequence loading experimental device;
according to the experimental data, determining a stress-strain curve of the brittle medium rod material under the time sequence forced loading in the impact-explosion experimental process;
and establishing a propagation attenuation model of the time sequence forced dynamic load in the brittle medium by using the experimental data and the stress-strain curve, and determining a utilization dissipation rule of the composite stress wave energy in the dynamic brittle fracture process after the time sequence forced dynamic load is propagated to the end part of the brittle medium rod with the hollow hole through the propagation attenuation model.
2. The method according to claim 1, wherein the impact-explosion time sequence loading experimental device is provided with a brittle medium rod, the brittle medium rod is used for transmitting composite stress waves caused by impact-explosion time sequence loading, the brittle medium rod is provided with a speckle region, and the experimental data comprises speckle region deformation image data; determining a stress-strain curve of the brittle medium rod material under the time sequence forced loading in the impact-explosion experimental process according to the experimental data, wherein the stress-strain curve comprises the following steps:
determining the axial displacement field distribution and the axial velocity field distribution of the surface particles of the brittle medium rod based on the speckle region deformation image;
determining an axial strain time course curve of the brittle medium rod caused by a time sequence strong dynamic load generated in the impact-explosion experimental process according to the axial displacement field distribution and a stress wave mass conservation equation under a Lagrange coordinate system;
determining the axial stress time-course curve of the brittle medium rod caused by the time sequence forced loading generated in the impact-explosion experimental process according to the axial displacement field distribution, the stress fluctuation conservation equation under the Lagrange coordinate system and the path line method integral;
and obtaining a stress-strain curve of the brittle medium material under the time sequence dynamic load based on the strain time course curve and the stress time course curve.
3. The method of claim 2, wherein the step of determining an axial displacement field distribution and an axial velocity field distribution of the surface particles of the brittle medium rod based on the speckle region deformation image comprises:
and utilizing DIC technology to carry out image analysis processing on the speckle region deformation image data, and determining the axial displacement field distribution and the axial velocity field distribution of the surface particles of the brittle medium rod under the time sequence forced loading.
4. The method of claim 2, wherein the brittle media bar is provided with a super-dynamic strain gauge, the experimental data including strain gauge measurements; the establishing of the propagation attenuation model of the time sequence forced loading in the brittle medium based on the experimental data and the stress-strain curve comprises the following steps:
extracting waveform time-frequency characteristics of the measurement result of the ultra-dynamic strain gauge;
determining the change data of the time-frequency characteristics of the composite stress waveform according to the propagation distance of the impact-explosion dynamic load; wherein the change data comprises one or more of propagation velocity, transflectance coefficient, spectral characteristics, band energy, and fractal characteristics;
and establishing a time sequence forced dynamic load propagation attenuation model based on the damping attenuation parameters of the brittle medium rod, the change data and the stress-strain curve.
5. The method according to claim 1, wherein the impact-explosion time sequence loading experiment device is provided with a brittle medium rod, and one end of the brittle medium rod is provided with a hollow hole to be crushed; the method is characterized in that after the propagation attenuation model determines that the time sequence forced dynamic load is propagated to the end part of the brittle medium rod with the hollow hole, the utilization and dissipation rule of the energy of the composite stress wave in the dynamic brittle fracture process is determined, and comprises the following steps:
calculating stress time-course information acting on the hollow hole to be crushed through the time-sequence strong dynamic load propagation attenuation model;
acquiring a hole fracture image corresponding to the hole to be crushed;
determining the effective stress wave energy consumed in the fracture process of the hollow hole to be crushed based on the image of the fracture process of the hollow hole and in combination with the screening result of the fragile medium fragments;
based on effective stress wave energy for brittle fracture, utilizing a inoculation characteristic time criterion to perform energy utilization analysis on the stress time-course information, wherein the stress time-course information is obtained through the propagation attenuation model, and is the stress time-course information in the brittle medium after the time sequence strong dynamic load is propagated to the end part of the brittle medium rod with the hollow hole, so that the distribution and the proportion rule of the stress wave energy consumed by the dynamic brittle fracture in a composite stress waveform time domain and a composite stress waveform frequency domain are further obtained;
wherein, the utilization dissipation rule comprises a distribution rule and a proportion rule.
6. An apparatus for analyzing shock-explosion time sequence loading experimental data, comprising:
the data acquisition module is used for acquiring experimental data; wherein the experimental data is generated in the process of carrying out the impact-explosion experiment in the impact-explosion time sequence loading experimental device;
the material mechanical property determining module is used for determining a stress-strain curve of the brittle medium rod material under the time sequence forced load in the impact-explosion experiment process according to the experiment data;
and the rule determining module is used for establishing a propagation attenuation model of the time sequence strong dynamic load in the brittle medium by using the experimental data and the stress-strain curve, and determining a utilization dissipation rule of the composite stress wave energy when dynamic brittle fracture occurs after the time sequence strong dynamic load is propagated to the end part of the brittle medium rod with the hollow hole through the propagation attenuation model.
7. The device according to claim 6, wherein the impact-explosion time sequence loading experimental device is provided with a brittle medium rod, the brittle medium rod is used for transmitting a composite stress wave caused by impact-explosion time sequence loading, the brittle medium rod is provided with a speckle region, and the experimental data comprises speckle region deformation image data; the material mechanical property determination module is further configured to:
determining the axial displacement field distribution and the axial velocity field distribution of the surface particles of the brittle medium rod based on the speckle region deformation image;
determining an axial strain time course curve of the brittle medium rod caused by a time sequence strong dynamic load generated in the impact-explosion experimental process according to the axial displacement field distribution and a stress wave mass conservation equation under a Lagrange coordinate system;
determining a corresponding stress time course curve when the brittle medium deforms due to the time sequence forced loading generated in the impact-explosion experimental process according to the axial displacement field distribution, the stress fluctuation conservation equation under the Lagrange coordinate system and the path line method integral;
and obtaining a stress-strain curve of the brittle medium material under the time sequence dynamic load based on the strain time course curve and the stress time course curve.
8. The apparatus of claim 7, wherein the material mechanical property determination module is further configured to include:
and utilizing DIC technology to carry out image analysis processing on the speckle region deformation image data, and determining the axial displacement field distribution and the axial velocity field distribution of the surface particles of the brittle medium rod under the time sequence forced loading.
9. An electronic device comprising a processor and a memory, the memory storing computer-executable instructions executable by the processor, the processor executing the computer-executable instructions to implement the method of any of claims 1 to 5.
10. A computer-readable storage medium having computer-executable instructions stored thereon which, when invoked and executed by a processor, cause the processor to perform the method of any of claims 1 to 5.
CN202211122745.6A 2022-09-15 2022-09-15 Analysis method and device for impact-explosion time sequence loading experimental data Pending CN115479851A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116539732A (en) * 2023-06-27 2023-08-04 北京航空航天大学 Device and method for detecting external shock wave loading process and attenuation rule
CN117825185A (en) * 2024-03-05 2024-04-05 北京理工大学 Method and system for determining dynamic strength of brittle material

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116539732A (en) * 2023-06-27 2023-08-04 北京航空航天大学 Device and method for detecting external shock wave loading process and attenuation rule
CN116539732B (en) * 2023-06-27 2023-10-03 北京航空航天大学 Device and method for detecting external shock wave loading process and attenuation rule
CN117825185A (en) * 2024-03-05 2024-04-05 北京理工大学 Method and system for determining dynamic strength of brittle material
CN117825185B (en) * 2024-03-05 2024-06-04 北京理工大学 Method and system for determining dynamic strength of brittle material

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