CN113324831B - Method for testing dynamic instability failure mechanism of goaf in strip mine slope - Google Patents
Method for testing dynamic instability failure mechanism of goaf in strip mine slope Download PDFInfo
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Abstract
The invention provides a method for testing a dynamic instability damage mechanism of a goaf in a strip mine slope, which relates to the field of research on the damage mechanism of the strip mine goaf, acquires mine site parameters, and determines the similarity ratio of a model to a site; casting a model based on similar materials and proportions required by model manufacture, and embedding a force sensor and a simulated goaf sacrificial member in the model; processing the maintained model, establishing a side slope, removing the sacrifice part to obtain a goaf, arranging acoustic sensors, and constructing a model strain monitoring array and blasting blastholes; acquiring and analyzing sound data, model stress data and model deformation data during blasting; by constructing a similar model test body, carrying out a blasting test on the model test body, acquiring acoustic emission signals, stress data and displacement data related to goaf dynamic instability damage characteristics, monitoring the dynamic disturbance process of explosion stress waves, and meeting the research data requirements of a goaf dynamic instability damage mechanism of an opencast mine.
Description
Technical Field
The disclosure relates to the field of strip mine goaf damage mechanism research, in particular to a strip mine slope goaf dynamic instability damage mechanism test method.
Background
Goaf refers to the space left after mining of the underground mine ore. In the mining process of the surface mine, along with continuous stripping of the mining of the surface mine steps, the safety thickness of each step and the stolen goaf in the mining boundary is thinner and thinner, and sudden collapse of the ground surface is easily caused, so that casualties and permanent damage of ground equipment are caused. Engineering practice shows that the upper step of the surface mine is damaged in the lower rock body under the action of blasting disturbance, and the damaged area is continuously enlarged along with the increase of blasting disturbance times, so that a stress concentration area is easily formed on the goaf top plate of the lower step, and the goaf top plate is easily unstable and damaged due to the creep effect of the upper step.
Because the mine site scale is large, the goaf visual instability damage mechanism is difficult to study through complete monitoring equipment, and the damage process of the actual engineering is mostly inverted by adopting a means of an indoor large-scale analogue simulation test. For example, the invention patent 201210376520.3 three-way loading large-scale three-dimensional similar simulation test system simulates the stress and displacement evolution process of a rock-covering roof in the underground mining process through three-way static loading, so as to obtain the failure mechanism of the roof; the patent 201910147195.5 is based on a method for testing the fracture law of a cover rock key layer of a similar simulation test system, and researches on the instability and damage mechanism of a top plate of an underground stope in the process of superposition of dynamic and static loads are carried out in a force application mode of three-dimensional static load and fixed-point dynamic load.
A similar simulation test for researching the dynamic instability failure mechanism of the underground mining space basically adopts a two-dimensional loading mode or a three-dimensional loading mode. Meanwhile, a fixed-point dynamic load (pendulum bob disturbance and the like) is applied, and the dynamic impact process of underground blasting is simulated in an energy conversion mode, so that the method is convenient for laboratory operation, has a large difference from an actual working condition, and cannot reflect the dynamic disturbance process of the explosion stress wave. The surface mine has great variability compared with the underground mine, and one of the main reasons of the dynamic instability damage of the shallow goaf in the side slope of the surface mine is the dynamic disturbance process from the explosion stress wave, so that the data acquired by adopting the existing loading disturbance method can not meet the research requirement of the dynamic instability damage of the actual engineering of the surface mine.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention provides a goaf dynamic instability damage mechanism test method in a strip mine slope, which comprises the steps of constructing a similar model test body, carrying out a blasting test on the model test body, acquiring acoustic emission signals, stress data and displacement data related to goaf dynamic instability damage characteristics, monitoring the dynamic disturbance process of explosion stress waves, and meeting the research data requirements of the goaf dynamic instability damage mechanism of the strip mine.
In order to achieve the above purpose, the following technical scheme is adopted:
a goaf dynamic instability damage mechanism test method in a strip mine slope comprises the following steps:
acquiring mine site parameters, and determining the similarity ratio of a model to the site;
casting a model based on similar materials and proportions required by model manufacture, and embedding a force sensor and a simulated goaf sacrificial member in the model;
processing the maintained model, establishing a side slope, removing the sacrifice part to obtain a goaf, arranging acoustic sensors, and constructing a model strain monitoring array and blasting blastholes;
and acquiring and analyzing acoustic data, model stress data and model deformation data during blasting.
Further, the mechanical parameters of the rock on the mine site, the stope size and the data of the preset blasting explosive amount are obtained, and the similarity ratio is determined according to the similarity law.
Further, the similarity ratio includes a geometric similarity ratio, a mass density similarity ratio, a time similarity ratio, a rock strength similarity ratio, and an explosive quantity similarity ratio.
Furthermore, when the model is poured, layering and repeated feeding pouring are adopted, and a tension-compression force sensor and a sacrificial member are embedded.
Further, the tension and compression force sensors are respectively arranged in the top plate and the upper part areas of the sacrifice piece corresponding to the goaf position, and a plurality of tension and compression force sensors arranged in each area are sequentially and equally arranged at intervals.
Further, the acoustic sensors are acoustic emission sensors, and a plurality of acoustic sensors are respectively arranged on the top plate and the bottom plate of the goaf to form an envelope of the goaf.
Further, the blasting blastholes are constructed for a plurality of times, and each time the blasting blastholes are constructed, a blasting test is carried out.
Further, according to the time similarity ratio, multiple blasting tests are sequentially carried out on the slope step positions in a superposition mode.
Further, a deformation detection surface of the model body is processed, grid-shaped monitoring array pixel points are constructed, and the grid-shaped monitoring array pixel points are monitored by acquiring images.
Further, collecting and processing data to obtain stress data, full-field strain data and acoustic emission data of the goaf dynamic instability destruction process, and analyzing the goaf dynamic instability destruction mechanism according to the stress data, the full-field strain data and the acoustic emission data.
Compared with the prior art, the present disclosure has the advantages and positive effects that:
(1) By constructing a similar model test body, carrying out a blasting test on the model test body, acquiring acoustic emission signals, stress data and displacement data related to goaf dynamic instability damage characteristics, monitoring the dynamic disturbance process of explosion stress waves, and meeting the research data requirements of a goaf dynamic instability damage mechanism of an opencast mine.
(2) According to actual engineering conditions and a blasting production plan, a dynamic instability damage mechanism of the goaf of the strip mine is revealed through a blasting disturbance test, and effective identification of stress, displacement and acoustic emission signals in the goaf dynamic disaster process is achieved, so that a more reliable test method is provided for instability damage and early warning prediction of the goaf of the strip mine under blasting disturbance.
(3) The pixel points are distributed on the observation surface of the model test body at equal intervals, so that the change trend of the displacement and the strain of the whole process of 'stability-damage-instability' of the slope and the goaf can be monitored under repeated cyclic blasting disturbance.
(4) And analyzing basic rules of stress accumulation, stress transfer, displacement change and energy release of surrounding rock of the goaf through distribution and evolution processes of a stress field, a displacement field and an acoustic emission field, and obtaining characteristics and precursor rules of dynamic instability damage of the goaf.
Drawings
The accompanying drawings, which are included to provide a further understanding of the disclosure, illustrate and explain the exemplary embodiments of the disclosure and together with the description serve to explain the disclosure, and do not constitute an undue limitation on the disclosure.
FIG. 1 is an overall schematic diagram of a similar model in example 1 of the present disclosure;
FIG. 2 is an enlarged schematic view of a portion of a goaf of a similar model in embodiment 1 of the present disclosure;
FIG. 3 is a graph of the dynamic destabilization destruction effect of the goaf in example 1 of the present disclosure;
FIG. 4 is a plot of goaf roof stress versus displacement time for example 1 of the present disclosure;
FIG. 5 is a plot of stress versus displacement time at the goaf shoulder in example 1 of the present disclosure;
FIG. 6 is a plot of goaf 0 deg. upper stress versus displacement time for example 1 of the present disclosure;
FIG. 7 is an acoustic emission signal energy versus time graph in example 1 of the present disclosure;
FIG. 8 is a dominant frequency versus time plot of an acoustic emission signal in example 1 of the present disclosure;
fig. 9 is a ringing count versus time graph of an acoustic emission signal in embodiment 1 of the present disclosure.
In the figure, a 1-pouring test body, a 2-goaf, a 3-blast hole, a 4-full-field strain pixel point, a 5-blast hole, a 6-full-field strain monitor, a 7-miniature tension-compression stress sensor, an 8-acoustic emission sensor, a 9-crack, a goaf after 10-instability damage, an A-first blasting region, a B-second blasting region and a C-third blasting region.
Detailed Description
Example 1
In an exemplary embodiment of the present disclosure, as shown in fig. 1-9, a method of testing a goaf dynamic instability failure mechanism in a strip mine slope is provided.
The technology capable of capturing the goaf dynamic instability destruction characteristics is provided, a rock mass damage and a 'caving' mechanism of surrounding rock mass in the goaf dynamic instability destruction process in a side slope are mastered based on a similar simulation test, an 'acceleration' catastrophe influence rule caused by blasting disturbance is further mastered, and data support is provided for goaf dynamic instability destruction induced by simulated dynamic disturbance in a laboratory at present.
The method comprises the following steps:
acquiring mechanical parameters of rock on the mine site, stope size and preset blasting explosive quantity data, and determining a similarity ratio according to a similarity law;
based on similar materials and a ratio casting model required by model manufacture, adopting layering and repeated feeding casting, and embedding a tension-compression stress sensor and a sacrificial member when the model is cast;
processing the maintained model, establishing a side slope, removing the sacrifice part to obtain a goaf, arranging acoustic emission sensors to form an envelope of the goaf, and constructing a model strain monitoring array and blasting blastholes;
according to the time similarity ratio, overlapping and sequentially carrying out multiple blasting tests at the step positions of the side slope;
and acquiring sound data, model stress data and model deformation data during blasting to obtain stress data, full-field strain data and sound emission data of the goaf dynamic instability destruction process, and analyzing the goaf dynamic instability destruction mechanism according to the stress data, the full-field strain data and the sound emission data.
The test method provided for the embodiment with reference to the attached drawings comprises the following steps:
step one: determining physical and mechanical parameters of rocks in a mine site, stope dimensions, explosive quantity and other physical quantities according to engineering geological data, determining a similarity ratio of the physical quantities according to a similarity law, and determining similar materials and proportions thereof by adopting an orthogonal experiment method;
step two: weighing and pouring a model test body according to the similar material proportion, arranging a miniature tension-compression force sensor in the pouring process, and burying a goaf model into the model test body;
step three: after the maintenance of the model is finished, the empty area model in the second step is sawed and emptied layer by layer for multiple times by using a saw blade, and the goaf manufacturing is completed;
drawing full-field strain pixel points on the front surface of the model test body for later full-field strain monitoring;
according to the geometric similarity ratio, completing manufacturing of a blast hole by adopting an electric hammer, and placing a detonator in the blast hole;
acoustic emission sensors are arranged on the top plate and the bottom plate of the goaf;
step four: and (3) connecting the tension-compression stress sensor, the acoustic emission sensor and the full-field strain monitor in the step II to a power supply, detonating a detonator, and monitoring acoustic emission signals, stress data and displacement data in the destabilization and destruction process of the goaf under the influence of blasting disturbance.
The above steps are described in detail in connection with the accompanying drawings and incorporated in a set of data.
For step one: and determining the similarity ratio according to physical and mechanical parameters of the rock at the mine site, the stope size, the explosive quantity and other physical quantities.
According to the law of similarity, the dimensions of each physical quantity can be obtained by using the dimensions of the three physical quantities. In the embodiment, a force dimension [ F ], a length dimension [ L ] and a time dimension [ T ] are adopted as a basic dimension system, so that the dimensions of each physical quantity can be obtained, and then the similarity ratio of each physical quantity can be obtained.
In this example, as shown in FIG. 1, the geometric similarity ratio is 100, the mass density similarity ratio is 1.7, the time similarity ratio is 10, the rock strength similarity ratio is 170, and the explosive amount is determined according to the similarity lawThe similarity ratio was 1.7X10 6 Thus, the two-dimensional plane strain model of the simulation test body 1 of the present embodiment was determined to have dimensions of length×height×width=2100 mm×1500mm×300mm, in which the goaf 2 has dimensions of length×height×width=550 mm×80mm×300mm.
Because the actual engineering field size is larger and the blasting production period is longer, the geometric dimension and the time are selected as basic physical units of a similar law intentionally in the implementation case. Other embodiments may choose the basic physical units according to specific needs.
In other embodiments, other similarity ratios can be selected, and the adaptability adjustment can be performed according to actual test requirements, so that the requirements of the test can be met.
When determining the similar materials and the proportions thereof, gypsum and calcium carbonate are selected as cementing materials, river sand and barite are selected as aggregates, the mass ratio of the aggregates to the cementing materials is 9, the mass ratio of the calcium carbonate to the gypsum is 3.46, the mass ratio of the barite powder to the aggregates is 0.11, and the water amount is 1/10 of the mass of the model.
Further, the gypsum is high-strength gypsum powder, the calcium carbonate is heavy calcium carbonate, the river sand is fine river sand with the grading particle size smaller than 1mm, and the particle size of the barite is 0.5-1 mm.
For step two: weighing heavy calcium carbonate, water, gypsum, sand and barite required by manufacturing the model test body 1 according to the similar material proportion. In order to maximize the homogeneity of similar materials, firstly, putting various dry materials into a stirrer for stirring, after various materials are uniformly stirred, adding a proper amount of water for multiple times for continuous stirring until the materials reach the homogeneity requirement;
the height of the model test body 1 is 1500mm, 15 layers are poured, and each layer is 100mm thick. According to the arrangement position of the sensor in fig. 2, the miniature tension-compression force sensor 7 is arranged in the pouring process, and meanwhile, the sacrifice piece of the goaf 2 is embedded into the model test body 1.
The method comprises the steps of performing model manufacturing by adopting a casting mode of casting and tamping, wherein the upper areas are the arch shoulder positions and the 0-degree upper positions, burying a miniature tension-compression force sensor 7 at intervals of 2cm at the top plate, the arch shoulder positions and the 0-degree upper positions of the goaf 2, burying 4 miniature tension-compression force sensors in each area, and adding up to 12 miniature tension-compression force sensors; 4 acoustic emission sensors 8 are uniformly distributed on the top plate and the bottom plate of the goaf 2 respectively, so that the goaf 2 is enveloped; in this embodiment, the shoulder is at a 45 ° upper position.
In order to ensure the compactness of the pouring materials, the similar materials which are uniformly stirred are added into each layer of pouring body twice, and the materials with the height of about 5cm are fully tamped each time, so that the reciprocating operation is performed until the manufacturing of the molded body is finished, and the lead is prevented from being damaged by overlarge force in the tamping process.
In this embodiment, in order to facilitate subsequent removal of the sacrificial body, a polyurethane foam mold is selected for the sacrificial body.
For step three: in order to ensure that similar materials are completely tamped, a side slope is not prefabricated when a similar model test body 1 is manufactured, after the model is maintained for 28 days, a saw bow model body is accurately cut according to the designed geometric dimension, and a small iron shovel and sand paper are used for flattening, so that the manufacture of the side slope is completed;
the polyurethane foam model prefabricated in the model pouring process is sawed and emptied layer by layer for a plurality of times by using a saw blade, and the production of the goaf 2 is completed;
further, in order to meet the requirements of full-field strain monitoring white background, the front surface of the similar model body 1 is painted, and gypsum is adopted: lime=1:1, adding a proper amount of water for painting, airing for half a day after each painting, grinding with sand paper after painting for three times, printing a plurality of square grids of 15mm multiplied by 15mm on an A3 drawing, hollowing the square grids, wherein the A3 drawing is a manufacturing substrate of the full-field strain monitoring pixel point 4, and adopting a writing brush and ink to carry out point distribution on the blank grids to finish manufacturing of the pixel point 4.
Further, a drill bit with the diameter of 2cm is matched with an electric hammer to finish the manufacture of a blasthole 3 with the blasting layer of 15cm, in order to ensure that the depth of the blasthole 3 meets the test requirements, the electric hammer is utilized to drill back in the hole after the hole is drilled so as to remove scum in the hole, and then an electric detonator 5 is placed in the hole 3 and the blasthole is filled with yellow mud.
For step four: and (3) connecting various sensor leads into corresponding data acquisition instruments, starting detonator 5 to blast, completing the first step A blasting, completing the blast holes required by the second blasting B according to the time similarity ratio, starting detonator blasting, and ending the third step C blasting in a circulating and reciprocating manner.
Further, stress data, full-field strain data and acoustic emission data of the destabilization and destruction process of the goaf 2 in the process of collecting and arranging blasting disturbance are respectively drawn into a top plate stress-displacement time curve shown in fig. 4, a stress-displacement time curve at a spandrel part shown in fig. 5, a 0-degree upper stress-displacement time curve shown in fig. 6, an acoustic emission signal energy-time diagram shown in fig. 7, an acoustic emission signal dominant frequency-time diagram shown in fig. 8 and an acoustic emission signal ringing count-time diagram shown in fig. 9.
In this embodiment, computational analysis is performed from the data carried in:
referring to fig. 3-6, analysis is performed according to model stress data and model deformation data, which shows that a stress concentration zone is formed in an area of an upper step slope toe at a left arch shoulder of a top plate of the goaf 2 under the action of multiple blasting disturbance, meanwhile, key rock blocks are generated by cutting the top plate of the goaf 2 through the cracks 9 under the action of multiple cracks 9, and finally unstable caving occurs under the long-term action of 45-degree upper angle stress concentration and self gravity of the left side of the goaf 2, and the damage mode of the top plate of the goaf 2 is arch caving. The displacement change before the falling of the measuring points at the top plate of the goaf 2 is more sensitive than the stress change, and the phenomenon of 'twice increase' of the displacement occurs at each measuring point before the falling of the top plate; the stress change of the 0-degree upper part is more sensitive than the displacement change, and the stress of the measuring point before the top plate is dropped shows the phenomenon of 'two-section pressure relief'; the stress mode of stretching-unloading-compression shearing is shown on the stress of the measuring point at the arch shoulder.
Further, referring to fig. 7-9, analysis is performed according to the change characteristics of the acoustic emission signals, and a large number of high-intensity, high-energy and large-scale fracture events are generated at the moment of blasting disturbance, and acoustic emission response is represented by the occurrence of a large number of acoustic emission signals with high energy, high ringing count and low main frequency; with the increase of blasting disturbance times, the intensity and the activity degree of the internal cracking activity of the goaf are gradually increased, so that the goaf top plate starts to generate high-energy, high-strength and large-scale cracking events only under the action of stress concentration and dead weight stress, and the goaf top plate shows obvious precursor characteristics in acoustic emission response, and finally, large-area caving occurs.
The failure mechanism of the goaf dynamic instability of the strip mine can be considered as follows: the acceleration effect of the multiple blasting disturbance is mainly that stress wave power is loaded to enable cracks to be initiated and expanded to promote the development of a rock stratum fracture network, so that the acceleration effect of the rock mass damage weakening process is achieved, and the development of roof caving is accelerated.
Based on the analysis result, the following acoustic emission signal characteristics can be used as early warning information of the dynamic instability damage of the goaf of the strip mine:
1. a large number of high-strength and high-energy cracking events are suddenly generated on the goaf roof after blasting disturbance;
2. the main frequency value of the acoustic emission signal gradually concentrates to the low-frequency stage;
3. the ringing count of the acoustic emission signal suddenly increases after the blasting disturbance.
According to actual engineering conditions and a blasting production plan, a dynamic instability damage mechanism of the goaf of the strip mine is revealed through a blasting disturbance test, and effective identification of stress, displacement and acoustic emission signals in the goaf dynamic disaster process is achieved, so that a more reliable test method is provided for instability damage and early warning prediction of the goaf of the strip mine under blasting disturbance.
The foregoing description of the preferred embodiments of the present disclosure is provided only and not intended to limit the disclosure so that various modifications and changes may be made to the present disclosure by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.
Claims (2)
1. A method for testing a goaf dynamic instability failure mechanism in a strip mine slope is characterized by comprising the following steps:
acquiring mine site parameters, and determining the similarity ratio of the model to the site, wherein the similarity ratio comprises a geometric dimension similarity ratio, a mass density similarity ratio, a time similarity ratio, a rock strength similarity ratio and an explosive quantity similarity ratio;
when the model is manufactured, the similar materials and the proportion thereof are required to be determined, gypsum and calcium carbonate are selected as cementing materials, river sand and barite are selected as aggregates, the mass ratio of the aggregates to the mass ratio of the cementing materials is 9, the mass ratio of the calcium carbonate to the mass ratio of the gypsum is 3.46, the mass ratio of the barite powder to the mass ratio of the aggregates is 0.11, the water quantity is 1/10 of the mass of the model, the gypsum is high-strength gypsum powder, the calcium carbonate is heavy calcium carbonate, the river sand is fine river sand with the grading particle size smaller than 1mm, and the particle size of the barite is 0.5-1 mm;
weighing heavy calcium carbonate, water, gypsum, sand and barite required by manufacturing the model test body 1 according to the proportion of similar materials, firstly putting various dry materials into a stirrer for stirring in order to maximize the homogeneity of the similar materials, and after the various materials are uniformly stirred, adding a proper amount of water for multiple times for continuous stirring until the materials reach the homogeneity requirement;
the method comprises the steps of manufacturing a casting model based on similar materials and proportions required by the model, adopting a layering and repeated feeding casting mode when the model is cast, and embedding a force sensor and a simulated goaf sacrificial member in the casting model process; the method comprises the steps that tension and compression force sensors are respectively arranged in the top plate and the upper part areas of the sacrificial piece corresponding to the goaf, and a plurality of tension and compression force sensors arranged in each area are sequentially arranged at equal intervals; the method specifically comprises the following steps: the method comprises the steps of performing model manufacturing by adopting a casting mode of casting and tamping, wherein a miniature pulling and pressing stress sensor is embedded at the positions of a goaf top plate, an arch shoulder and a 0-degree upper part every 2cm, 4 miniature pulling and pressing stress sensors are embedded in each region, and the total number of miniature pulling and pressing stress sensors is 12; 4 acoustic emission sensors are uniformly distributed on the top plate and the bottom plate of the goaf respectively, so that the goaf is enveloped; the arch shoulder is at a 45-degree upper position;
and (3) processing the cured model, establishing a side slope, removing the sacrifice part to obtain a goaf, arranging acoustic sensors, and constructing a model strain monitoring array and blasting blastholes, and specifically: the acoustic sensors are acoustic emission sensors, and a plurality of acoustic sensors are respectively arranged on the top plate and the bottom plate of the goaf to form an envelope of the goaf; processing a deformation detection surface of the model body, constructing grid-shaped monitoring array pixel points, and monitoring the grid-shaped monitoring array pixel points by acquiring images; constructing blasting blastholes for multiple times, performing a blasting test once every time when blasting blastholes are constructed, and sequentially performing multiple blasting tests at the step positions of the side slope in a superposition manner according to the time similarity ratio;
the manufacturing method of the pixel point specifically comprises the following steps: the method comprises the steps that the whole-field strain monitoring needs to meet the requirement of a white background, the front surface of a similar model body 1 is painted, gypsum and lime are proportioned, proper amount of water is added for painting, the paint is dried after painting for each time, a plurality of squares with the same size are ground by sand paper after painting for many times, the squares are printed on a drawing, the drawing is hollowed, the drawing is a manufacturing substrate of a whole-field strain monitoring pixel point, and writing brush and ink are adopted for distributing points in a blank lattice, so that the pixel point is manufactured;
by constructing a similar model test body, carrying out a blasting test on the model test body, acquiring acoustic emission signals, stress data and displacement deformation data related to goaf dynamic instability damage characteristics, analyzing basic rules of stress accumulation, stress transfer, displacement change and energy release of goaf surrounding rock through the distribution and evolution processes of the stress field, the displacement field and the acoustic emission field, acquiring the goaf dynamic instability damage characteristics and precursor rules, monitoring the dynamic disturbance process of explosion stress waves, and meeting the research data requirements of a goaf dynamic instability damage mechanism of an open-pit mine.
2. The method for testing the dynamic instability failure mechanism of the goaf in the slope of the strip mine according to claim 1, wherein the mechanical parameters of the rock in the mine site, the stope size and the data of the predetermined blasting explosive amount are obtained, and the similarity ratio is determined according to the similarity law.
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| CN108331042A (en) * | 2018-03-05 | 2018-07-27 | 武汉科技大学 | A kind of experimental rig and test method of the influence of simulation Blasting Excavation side slope |
| CN112903169A (en) * | 2021-01-26 | 2021-06-04 | 北京科技大学 | Quantitative analysis experiment method for explosion stress wave propagation full-field main stress |
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| CN112903169A (en) * | 2021-01-26 | 2021-06-04 | 北京科技大学 | Quantitative analysis experiment method for explosion stress wave propagation full-field main stress |
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