CN107421818A - Blasting simulation test device and method based on geomechanical model test - Google Patents

Blasting simulation test device and method based on geomechanical model test Download PDF

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Publication number
CN107421818A
CN107421818A CN201710875081.3A CN201710875081A CN107421818A CN 107421818 A CN107421818 A CN 107421818A CN 201710875081 A CN201710875081 A CN 201710875081A CN 107421818 A CN107421818 A CN 107421818A
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China
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test
blasting
reaction frame
simulation test
hydraulic
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CN201710875081.3A
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高魁
刘泽功
刘健
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Anhui University of Science and Technology
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Anhui University of Science and Technology
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Priority to CN201710875081.3A priority Critical patent/CN107421818A/en
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • G01N3/10Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces generated by pneumatic or hydraulic pressure
    • G01N3/12Pressure testing
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/30Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight
    • G01N3/313Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight generated by explosives
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/003Generation of the force
    • G01N2203/0042Pneumatic or hydraulic means
    • G01N2203/0048Hydraulic means
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0058Kind of property studied
    • G01N2203/006Crack, flaws, fracture or rupture
    • G01N2203/0062Crack or flaws
    • G01N2203/0066Propagation of crack
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02Details not specific for a particular testing method
    • G01N2203/0202Control of the test

Abstract

On the basis of comprehensive reference blasting simulation test device and Geotechnical Engineering multifunction test device, it is proposed that a set of large-scale very three-dimensional blasting simulation test device based on geomechanical model test.The experimental rig is mainly made up of reaction frame (1) and hydraulic jack (2), experiment casing (4) and its ancillary data monitoring device etc..By establishing geological structure coal and rock test model (5), using micro- dose controlled blasting powder column (6), data monitoring sensor and interface (3) are equipped with, to realize the combination of geomechanical model test and blasting simulation test.Experimental rig realizes true three-dimensional hydraulic loading, melt coal body, rock mass and complex geological structure to be integrated, blasting simulation test of the complex geological structure such as different joints, structural plane and weak intercalated layer and tomography, the fold band under different stress can be realized, a new thinking and test method is provided for the research safe and efficient theory of blasting of geological structural belt.

Description

Blasting simulation test device and method based on geomechanical model test
Technical field:
The present invention relates to a kind of blasting simulation test device and test method, more particularly to geomechanical model test with it is big The test method that the very three-dimensional blasting simulation test of size is combined.
Background technology:
With the continuous increase of coal mining intensity, application of the medium-length hole Controlled blasting technique in coal production is increasingly Extensively, gas pumping rate, tight roof overhead caving, the comprehensive relieving of high seam top hard coal are improved as low air permeability coal seam is anti-reflection Adopt, development blasting and stone door punching coal etc..
However, vibrations caused by explosion can produce strong influence to coal and rock, redistribution promotes coal petrography to stress rapidly Deterioration easily induces gas dynamical disaster.When underground geological structural belt coal and rock is arrived in bursting work disturbance, it is more prone to induce The generation of coal rock gas dynamic disaster.For example, Huainan Mining Group Pan thanks to mining area occurs Gas Outburst 56 times altogether, lured wherein blowing out Hair is prominent 40 times, accounts for the 71.43% of prominent sum.
The destructive process of coal and rock physical equilibrium state caused by only fully realizing concussion of blasting, solves mash gas dynamic calamity The key scientific problems that evil occurs, could formulate effective Controlled blasting technique, reach pre- while safety operating blasting technique Anti- explosion causes the purpose that gas dynamical disaster occurs.
Many scholars have made intensive studies to the relation of explosion and improving stability of surrounding rocks in roadway, connect using coal and rock as average Continuous medium considers.However, actual coal rock medium is mostly discontinuum, the mechanics problem in blasting process belongs to discontinuous media The structural plane control such as mechanics problem, joint that its explosion physical process, blast action mechanism and effect are developed in by coal and rock, crack System.
Although the existing precedent of simulated test research that Explosion stress wave is propagated at joint, structural plane and weak intercalated layer, Moulded dimension is smaller, in test without reference to geologic body, also fails to realize true triaxiality loading.
In consideration of it, on the basis of comprehensive reference blasting simulation test device and Geotechnical Engineering multifunction test device, base Thought and geomechanical model testing technology thinking are tested in analog simulation, it is proposed that a set of to be based on analog simulation and geomechanics The blasting simulation test device and test method of model test.
The content of the invention:
Problem to be solved by this invention is:What existing blasting simulation test used is carried out for isotropism homogeneous material Replica test, and experimental rig size is smaller, it is impossible to very three-dimensional loading is realized, does not account for geological structure, joint, structure The influence to demolition effect such as face and weak intercalated layer.
To solve the above problems, on the basis of geomechanical model testing technology, by designing large-scale very three-dimensional explosion Simulation test device, geological structural belt coal and rock test model is built, the condition of similarity of blasting simulation test is established, utilizes micro- medicine Controlled blasting technique is measured, to realize the combination of geomechanical model test and blasting simulation test.
The present invention is the blasting simulation test method based on geomechanical model testing technology, discloses a kind of large-scale three dimensional Blasting simulation test system, including 1 experiment casing, answer force transfering device, 1 set of true three-dimensional hydraulic loading system and reaction frame. Experiment casing includes the face U-type groove of monoblock cast five and upper cover plate, data monitoring sensor wire mouth, micro- dose controlled blasting detonator Wire outlet and blast hole, casing U-type groove inner chamber dead size are 2800mm × 2800mm × 2000mm, and the face of monoblock cast five is U-shaped Groove each side uniformly lays 14 and answers force transfering device;Experiment casing upper cover plate size is 2800mm × 2800mm, upper lid Plate uniformly lays 49 and answers force transfering device.Stress pass device include cylindrical pressurizing piston bar, piston base, fixing bolt and Pressure transmission increased pressure board, answer force transfering device pressurizing piston bar to be alignd with hydraulic jack, can move freely, main function is Transmit the stress of hydraulic jack.Hydraulic loading system is by 77 groups of SUNS hydraulic jacks, Japan only more hydraulic pump, the U.S. MOOG hydraulic efficiency servo-valves, Switzerland's ELCO displacement transducers, SUNS multi-channel servos closed-loop control system and pipeline road group Into hydraulic jack is connected by ring flange with reaction frame, and 7 groups of hydraulic jacks, left and right two are fixed at the top of each group of reaction frame Side is each to fix 2 groups of hydraulic jacks.
The present invention is before blasting simulation test is carried out, first according to the lithology distributions of the actual coal rock layer in mining area and ground texture Situation is made, geological structural belt coal and rock test model is established in laboratory.
Further, according to analog simulation test theory, it is determined that experiment coal rock medium body and the phase of geological structural belt coal and rock Like property, the similar material mixture scheme and preparation technology of geological structural belt coal and rock are determined.
Further, according to the test model for the structural belt geology coal and rock established, according to geomechanical model test side Method and similar material mixture scheme lay test model in experiment casing.
Further, in model process of deployment, in the precalculated position of experiment casing, arrangement is embedded to the three-dimensional inside coal and rock Vibrating speed sensors, piezoelectric membrane, strain brick and metal probe, by NUXI-1012 integrated form high-speed data acquisition instrument and The supporting virtual instrument application software of TopView2000, multi-channel data high speed acquisition instrument are acquired analysis to data.
Further, after modelling well, three-dimensional hydraulic loading system is assembled according to design requirement, answers force transfering device to pacify In experiment casing, experiment casing is placed in reaction frame, makes cylindrical the pressurizing piston bar and hydraulic pressure for answering force transfering device The hydraulic jack alignment of loading system, keeps constantly acting load to carry out stress loading.
Further, after geological structural belt coal and rock physical model lays completion and applies three-dimensional stress load, pre- Blast hole depth blast hole drilling of the position first set by electric drill according to design, hexogen explosive and detonator are loaded in borehole, is adopted With yellow mud sealing of hole.The analog simulation that blast disturbance geological structural belt coal and rock can be carried out by exploder detonating primer is tested.
In summary, beneficial effects of the present invention:Experimental rig realizes the loading of true three-dimensional hydraulic, melt coal body, rock mass and Complex geological structure is integrated, it is possible to achieve the complicated geology such as different joints, structural plane and weak intercalated layer and tomography, fold Blasting simulation test of the structural belt under different stress occurrence status, explore coal petrography under the conditions of complex geological structure band blast disturbance Dynamic instability mechanism, a new thinking and test method is provided for the research safe and efficient theory of blasting of geological structural belt.
Brief description of the drawings:
Fig. 1 is the blasting simulation test system structure of device schematic diagram of the present invention.
Fig. 2 is the blasting simulation test casing front view of the present invention and specific size.
Fig. 3 is the blasting simulation test casing side view of the present invention and specific size.
Fig. 4 is the blasting simulation test casing top view of the present invention and specific size.
Fig. 5 is the blasting simulation test casing piston rod and pressure plare and specific size of the present invention.
Fig. 6 is the blasting simulation test device reaction frame and hydraulic jack and specific size of the present invention.
Fig. 7 is micro- dose Controlled blasting technique powder charge pattern of the present invention.
Fig. 8 is the blasting simulation test example based on geomechanical model test of the present invention.
Wherein:1- reaction frames;2- hydraulic jacks;3- data monitoring sensor wire mouths;4- large-scale three dimensional Blasting simulations Experimental rig casing;5- geological structural belt coal and rocks;The micro- dose controlled blasting powder columns of 6-;7- cylinder pressurizing piston bars;8- lives Fill in base;9- piston pressure increased pressure boards;The micro- dose Controlled blasting technique detonator lead outlets of 10- and blast hole;11- bolts;12- Reaction frame entablature;13- reaction frame middle cross beams;14- reaction frame reinforcements;15- reaction frame cross members;16- hydraulic jack methods Blue disk;17- hexogen explosives;18- detonators;19- yellow mud;20- detonator leads;21- strains brick;22- stress surveys line;23- metals Probe;24- digging laneways.
Embodiment:
The present invention is carried out with blast disturbance structural belt Geological discontinuity coal petrography analog simulation test example below in conjunction with the accompanying drawings detailed Describe in detail bright.
Embodiment:As Figure 1-Figure 8, large-scale three dimensional blasting simulation test device, mainly including hydraulic loading system (1) and (2), experiment casing (4);The data monitoring sensor wire mouth (3) is arranged in the upper right side of experiment casing (4);Institute Micro- dose Controlled blasting technique is stated, hexogen explosive is loaded into blast hole and (17) and connects detonator (18), using yellow mud sealing of hole, Blasting simulation test is carried out by exploder detonating primer.
The present embodiment, the control action developed by analyzing tectonic movement to Geological discontinuity coal body, choose coal bed texture and break Bad constructs the test model that region is blast disturbance Geological discontinuity coal and rock, the structural belt geology coal body test model of foundation (5).Using varigrained coal dust as aggregate, the sodium humate aqueous solution is that cementing agent prepares moulded coal test specimen, according to orthogonal test side Method carries out adsorption-desorption to test specimen and mechanics parameter is tested, and investigates the similitude of test specimen and Geological discontinuity coal body, determines structural belt The similar material mixture scheme and preparation technology of Geological discontinuity coal body.
The present embodiment, according to geomechanical model test method and similar material mixture scheme in experiment casing (4) middle berth If test model.In model process of deployment, blast hole and the cloth above the excavation tunnel of experiment casing are reserved according to design attitude 4 stress surveys line (22) are put, strain brick (21) size that measuring point is buried is 20mm × 20mm × 20mm, is surpassed using SDY2107A Dynamic strain data collecting system gathers blasting process strain data in real time, and the inverting stress value;Between being waited above explosive Enamel covered wire (23) away from 7 diameter 0.14mm of arrangement is used as sensor material, and crackle is expanded with BSW-3A type intelligence detonation velocity meters Exhibition speed is tested, and is analyzed with DasView2.0 softwares.
The present embodiment, after modelling well, constantly acting load is kept to carry out stress loading.Vertically stress value by formula σ= γ h are calculated, and model and the prototype likelihood ratio are 1:40, coal seam buried depth is set to 900m, and the crustal stress in vertical reversed fault direction presses 1.5 γ H is calculated, and horizontal stress is applied by 1.75 times of cast material compression strength.
The present embodiment, apply stress using hydraulic loading system and preload two weeks, keep other conditions constant, filling is fried Medicine and detonator, using yellow mud sealing of hole, blast disturbance structural belt Geological discontinuity coal and rock can be carried out by exploder detonating primer Analog simulation experiment.

Claims (7)

1. a kind of blasting simulation test device and method based on geomechanical model test, its experimental rig are characterised by:By Experiment casing, force transfering device, hydraulic loading system and reaction frame composition, the experiment casing is answered to include the face U of monoblock cast five Type groove and upper cover plate, data monitoring sensor wire mouth, the outlet of micro- dose controlled blasting detonator lead and blast hole, the stress Passing device includes cylindrical pressurizing piston bar, piston base, fixing bolt and pressure transmission increased pressure board, the hydraulic loading system Including hydraulic jack, hydraulic pump, pipeline road and servo-control system, the reaction frame includes entablature, middle cross beam, reinforcement Muscle and cross member;Described to answer force transfering device to be arranged in experiment casing, the experiment casing is placed in reaction frame, and stress passes The cylindrical pressurizing piston bar of delivery device aligns with the hydraulic jack of hydraulic loading system;Its test method is characterised by:Structure Geological structural belt coal and rock test model is built, establishes the condition of similarity of blasting simulation test, utilizes micro- dose Controlled blasting technique Carry out simulated test.
2. a kind of blasting simulation test device and method based on geomechanical model test according to claim 1, its It is characterised by:The face U-type groove inner chamber dead size of experiment casing monoblock cast five is 2800mm × 2800mm × 2000mm, overall Cast five face U-type grooves and each side uniformly lay 14 and answer force transfering device, experiment casing upper cover plate size be 2800mm × 2800mm, upper cover plate uniformly lay 49 and answer force transfering device, and casing and upper cover plate thickness are 30mm;On front side of the experiment casing Leave the micro- outlet of dose controlled blasting detonator lead and blast hole, casing upper right side and leave data monitoring sensor wire mouth.
3. a kind of blasting simulation test device and method based on geomechanical model test according to claim 1, its It is characterised by:The substructure height for answering force transfering device is 100mm, and base bottom size is 200mm × 200mm, cylinder Pressurizing piston bar height 350mm, diameter 70mm;Each piston nose is connected with increased pressure board, applies the upper piston of vertical stress Pressure pressurization board size is 400mm × 400mm × 20mm, and the left and right sides piston pressure pressurization board size for applying horizontal stress is 2800mm×950mm×20mm。
4. a kind of blasting simulation test device and method based on geomechanical model test according to claim 1, its It is characterised by:The hydraulic loading system is watched by 77 groups of SUNS hydraulic jacks, Japan only more hydraulic pump, U.S.'s MOOG hydraulic pressure Take valve, Switzerland's ELCO displacement transducers, SUNS multi-channel servos closed-loop control system and pipeline road composition, hydraulic jack Top is connected by ring flange with reaction frame.
5. a kind of blasting simulation test device and method based on geomechanical model test according to claim 1, its It is characterised by:The reaction frame is by reaction frame entablature, reaction frame middle cross beam, reaction frame reinforcement and reaction frame cross member group Into reaction frame size is 5660mm (length) × 2800mm (width) × 3430mm (height), and reaction frame reinforcement is a diameter of 50mm Steel construction spiral cylinder, the entablature and cross member of each group of reaction frame and middle cross beam are connected through in the passing through of the left and right sides 4 reaction frame reinforcements of crossbeam and 8 bolts are completed, and 7 groups of hydraulic jacks, the left and right sides are fixed at the top of each group of reaction frame It is each to fix 2 groups of hydraulic jacks.
6. a kind of blasting simulation test device and method based on geomechanical model test according to claim 1, its Test method feature mainly includes the following steps that:
(1) structural belt geology coal body test model is established, similar material mixture is carried out according to the principle of similitude of analog simulation experiment, Test material is successively laid according to similar material mixture in experiment casing;
(2) in model process of deployment, it is embedded to data monitoring sensor;
(3) after modelling well, constantly acting load is kept to carry out stress loading;
(4) the blast hole depth blast hole drilling by electric drill according to design, carry out being based on similar mould using micro- dose Controlled blasting technique Fit the blasting simulation test of geomechanical model test.
7. a kind of blasting simulation test device and method based on geomechanical model test according to claim 1, its Micro- dose Controlled blasting technique is characterised by:Hexogen explosive is loaded in borehole after similar proportion calculates, is then loaded Detonating primer, blasthole is finally blocked using yellow mud, blast disturbance geological structure coal and rock is carried out by exploder detonating primer Analog simulation is tested.
CN201710875081.3A 2017-09-25 2017-09-25 Blasting simulation test device and method based on geomechanical model test Pending CN107421818A (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109187237A (en) * 2018-08-06 2019-01-11 华侨大学 A kind of tunnels and underground engineering Blasting Excavation model assay systems and test method
CN109682697A (en) * 2019-01-17 2019-04-26 北京信息科技大学 A method of measurement column charing is in rock interior blast action region
CN109754697A (en) * 2019-01-18 2019-05-14 安徽理工大学 A kind of similar physics experimental rig of three-dimensional of simulation fault movement
CN110672795A (en) * 2019-10-24 2020-01-10 中国人民解放军63653部队 Underground engineering anti-explosion model experimental device adopting explosive explosion loading mode
CN112435527A (en) * 2020-12-02 2021-03-02 哈尔滨工业大学(威海) Matching type box structure for simulating fault motion
CN112557171A (en) * 2020-12-02 2021-03-26 哈尔滨工业大学(威海) Soil layer top pressurizing device
CN112683561A (en) * 2020-12-02 2021-04-20 哈尔滨工业大学(威海) Earthquake fault simulation experiment platform
CN112435527B (en) * 2020-12-02 2022-11-01 哈尔滨工业大学(威海) Matching type box structure for simulating fault motion

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109187237A (en) * 2018-08-06 2019-01-11 华侨大学 A kind of tunnels and underground engineering Blasting Excavation model assay systems and test method
CN109682697A (en) * 2019-01-17 2019-04-26 北京信息科技大学 A method of measurement column charing is in rock interior blast action region
CN109754697A (en) * 2019-01-18 2019-05-14 安徽理工大学 A kind of similar physics experimental rig of three-dimensional of simulation fault movement
CN110672795A (en) * 2019-10-24 2020-01-10 中国人民解放军63653部队 Underground engineering anti-explosion model experimental device adopting explosive explosion loading mode
CN112435527A (en) * 2020-12-02 2021-03-02 哈尔滨工业大学(威海) Matching type box structure for simulating fault motion
CN112557171A (en) * 2020-12-02 2021-03-26 哈尔滨工业大学(威海) Soil layer top pressurizing device
CN112683561A (en) * 2020-12-02 2021-04-20 哈尔滨工业大学(威海) Earthquake fault simulation experiment platform
CN112435527B (en) * 2020-12-02 2022-11-01 哈尔滨工业大学(威海) Matching type box structure for simulating fault motion

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Application publication date: 20171201