CN103335903A - Blasting disturbance impact load precise simulation device - Google Patents
Blasting disturbance impact load precise simulation device Download PDFInfo
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- CN103335903A CN103335903A CN2013102455350A CN201310245535A CN103335903A CN 103335903 A CN103335903 A CN 103335903A CN 2013102455350 A CN2013102455350 A CN 2013102455350A CN 201310245535 A CN201310245535 A CN 201310245535A CN 103335903 A CN103335903 A CN 103335903A
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Abstract
The invention discloses a blasting disturbance impact load precise simulation device, belonging to the technical field of disturbance effect experiments of the mining industry and geotechnical engineering. The blasting disturbance impact load precise simulation device comprises a rack (15), upper and lower pressure bearing plates (5 and 8) mounted on the rack (15) and a measurement device, wherein a sample (7) is fixed between the upper and lower pressure bearing plates (5 and 8). The blasting disturbance impact load precise simulation device is characterized by also comprising a constant-load loading mechanism for applying a constant load to the sample (7), a disturbance loading mechanism for applying a disturbance load to the sample (7) and a main vibration frequency adjusting device for adjusting the main vibration frequency of the lower environment of the sample (7), wherein the main vibration frequency of the experiment environment of the sample (7) can be adjusted to be equal to the main vibration frequency tested on the scene by the main vibration frequency adjusting device, and the degree of damage of the mine and geotechnical engineering rock caused by the disturbance load is accurately simulated. The device disclosed by the invention has the advantages of accurate measurement data, convenience in operation, simple structure and the like.
Description
Technical field
The accurate analogue means of blast disturbance shock load belongs to mining industry and Geotechnical Engineering disturbance effect experimental technique field, is specifically related to samples such as a kind of obturation or rock at the experimental provision that is subjected to the destructiveness of disturbing load under influencing.
Background technology
The degree of injury of materials such as the obturation that causes because of explosion for obturation in effectively precisely simulate formation space engineering and surface mine, Lu Gou, the cutting isolith geotechnique Cheng Jikuang or rock; accurately analyze, estimate the stability of such engineering, must accurately grasp explosion feature in the construction, explosion number of times, blow-up point apart from the distance of protection point to being in the damage evolution rule of heterogeneity rock under the different pressures state.
Chinese patent 200610114015.6 discloses a kind of material flowing deformation disturbance effect experimental system and experimental technique, in experiment, apply shock vibration load by counterweight, apply blast disturbance load by detonator, by two real shock loads of disturbing load superposed simulation, this experimental system has the following disadvantages:
1, the disturbance shock load is only simulated in experiment, and sample at the scene with the laboratory in, the master oscillator frequenc of its environment of living in is different, by table five in the instructions and table six as can be seen, the resulting experimental result of master oscillator frequenc of whether simulating sample environment of living in differs greatly, if do not go to simulate master oscillator frequenc in the experiment, there are very large deviation in the result who obtains and actual numerical value, can't accurately instruct practice of construction.
2, counterweight impacts and is subjected to the influence at distance of fall, inclination angle, exists than mistake, and a plurality of counterweight stacks back falls, and has vibration between the counterweight, and the error of generation is bigger, and changes counterweight quality inconvenience at every turn; Simulate detonator blasting at present, because each detonator is also not in full accord each other, cause the data that repeatedly experiment draws to exist than mistake, utilize counterweight to impact like this and the detonator blasting resulting disturbing load error that superposes bigger, can't accurately instruct practice of construction.
Summary of the invention
The technical problem to be solved in the present invention is: overcome the deficiencies in the prior art, the blast disturbance shock load accurate analogue means of a kind of accurate simulation disturbing load to the damaged condition of sample is provided.
The technical solution adopted for the present invention to solve the technical problems is: the accurate analogue means of this blast disturbance shock load, comprise frame, rack-mounted upper and lower bearing plate and measurement mechanism, sample is fixed between the upper and lower bearing plate, it is characterized in that: also comprise for the dead load load maintainer that sample is applied permanent load, be used for sample is applied the disturbance load maintainer of disturbing load, and the master oscillator frequenc regulating device that is used for regulating sample bottom of living in environment master oscillator frequenc.
Described disturbance load maintainer comprises air forging hammer, and by the air compressor machine that the compressed gas pipeline is connected with air forging hammer, air forging hammer vertically is arranged on down the upper surface of bearing plate, and the compressed gas pipeline is provided with variable valve and switch; Air forging hammer can be adjusted the position of its relative sample on following bearing plate.
Described air forging hammer upper end is supported on upper rack crossbeam lower surface by vertical air forging hammer rigid support.
Described disturbance load maintainer applies disturbing load in a plurality of positions of the following relative sample of bearing plate, and sample produces different peak value vibration velocities.
Described dead load load maintainer comprises lever, depression bar and counterweight, and lever one end is hinged on the frame, and the other end is by pallet carry counterweight, and depression bar vertically is fixed between lever and the last bearing plate.
Described master oscillator frequenc regulating device is bed course, and bed course is arranged between disturbance load maintainer and the frame.
Described master oscillator frequenc regulating device is bed course, and bed course is arranged between bearing plate and the sample.
Described master oscillator frequenc regulating device is bed course, and bed course is arranged on down between bearing plate and the sample.
Described bed course material is leather.
Described measurement mechanism comprises blasting vibration instrument, nonmetal sonic detection instrument and static strain tester.
Compared with prior art, the beneficial effect that has of the accurate analogue means of blast disturbance shock load of the present invention is:
1, accurately simulates disturbing load to the damaged condition of sample, it is identical with the field measurement master oscillator frequenc to utilize the master oscillator frequenc regulating device can adjust the master oscillator frequenc of sample environment of living in the experiment, can reach laboratory condition with on-the-spot identical, data can accurately instruct practice of construction more accurately near real data;
2, easy to operate, can change the pressure of air forging hammer arbitrarily by variable valve, easy to adjust;
3, simple in structure, cost is low, whole device adopts common material to get final product, bed course can be selected common material.
Description of drawings
Fig. 1 is the accurate analogue means structural representation of blast disturbance shock load of the present invention.
Fig. 2 is that the peak value vibration velocity is with the curve synoptic diagram of variable in distance between air forging hammer and the sample.
Fig. 3 is the curve synoptic diagram that master oscillator frequenc changes with air forging hammer pressure.
Wherein: 1, lever 2, depression bar 3, counterweight 4, pallet 5, last bearing plate 6, bed course 7, sample 8, following bearing plate 9, compressed gas pipeline 10, variable valve 11, air compressor machine 12, switch 13, air forging hammer 14, air forging hammer rigid support 15, frame.
Embodiment
Fig. 1～3rd, the most preferred embodiment of the accurate analogue means of blast disturbance shock load of the present invention, the present invention will be further described below in conjunction with accompanying drawing 1～3.
With reference to accompanying drawing 1: the accurate analogue means of this blast disturbance shock load, comprise frame 15, dead load load maintainer and disturbance load maintainer, the rectangular through-hole that frame 15 bottoms connect for front and back between the plate of the left and right sides, frame 15 tops are provided with crossbeam, the dead load load maintainer comprises the lever 1 of horizontally set, and lever 1 one ends are hinged on frame 15 tops, and the other end stretches out frame 15 and hinged pallet 4, counterweight 3 is placed on the pallet 4, and lever 1 below is connected with a vertical depression bar 2 in frame 15.
Depression bar 2 lower end screw threads are connected with bearing plate 5 on the circle of level, the following bearing plate 8 that in frame 15 bottoms be provided with rectangle corresponding with last bearing plate 5, sample such as obturation or rock 7 is between upper and lower bearing plate 5,8, and the area of following bearing plate 8 is greater than the area of last bearing plate 5.Upper and lower bearing plate 5,8 and sample 7 between be provided with bed course 6, bed course 6 by unlike material, perhaps can be under uniform pressure by the bed course 6 of identical material different-thickness, make down bearing plate 8 produce different master oscillator frequencs, make down the master oscillator frequenc of bearing plate 8 identical with the master oscillator frequenc of field measurement by adjustment, the data that record of experiment have more practicality more near True Data like this.
The disturbance load maintainer comprises the air forging hammer 13 that vertically is fixed on down bearing plate 8 upper surfaces, air forging hammer 13 is positioned at the outside of bearing plate 5, the air intake opening of air forging hammer 13 is connected with air compressor machine 11 by compressed gas pipeline 9, and compressed gas pipeline 9 is provided with variable valve 10 and switch 12.By the dynamics that impacts that variable valve 10 can be regulated air forging hammer 13, simulate the disturbances of the different sizes of construction generations such as different explosions, 13 actions of switch 12 control air forging hammer.
Table one
With reference to Fig. 2～3: table one is that the different disturbing loads of experiment, distance are to the influence of peak value vibration velocity and master oscillator frequenc, as shown in Figure 2, under the identical disturbing load, the peak value vibration velocity changes with the variable in distance of air forging hammer 13 with sample 7, and master oscillator frequenc is constant; As shown in Figure 3, air forging hammer 13 is identical with the distance of sample 7, and master oscillator frequenc changes with the variation of disturbing load.
Test used measurement mechanism and comprise blasting vibration instrument, nonmetal sonic detection instrument and static strain tester.
Concrete experimental procedure is as follows:
Step 1: the several pressure of field measurement and distance be master oscillator frequenc and the peak value vibration velocity at scene down, and rock or cemented fill are chosen in the scene, a plurality of samples 7 of the identical size of making in laboratory.Pressure can specifically be selected 0.3MPa, 0.4MPa, 0.5MPa and 0.6MPa, and distance can specifically be selected 6cm, 12cm, 18cm and 24cm.
Step 2: utilize pressing machine that a sample 7 is damaged by pressure, obtain the broken ring load of sample 7
It is uniaxial compressive strength.
Step 3: an intact sample 7 is put between the upper and lower bearing plate 5,8, bearing plate 5 makes it closely contact with sample 7 in the adjustment, detecting instruments such as blasting vibration instrument, nonmetal sonic detection instrument and static strain tester are installed, the blasting vibration instrument probe is surveyed master oscillator frequenc and the peak value vibration velocity of bearing plate 8 down, nonmetal sonic detection instrument is connected sample 7 with the static strain tester, and the connection computing machine, adjust the permanent loaded load that is loaded on the sample 7 by counterweight 3
,
,
Between 0.2～0.8, choose.
Step 4: by between air forging hammer rigid support 14 upper ends and frame 15 upper beam, also laying bed course 6, and upper and lower bearing plate 5,8 and sample 7 between lay bed course 6, with step 1 uniform pressure under, by 13 actions of switch 12 control air forging hammer, the blasting vibration instrument records down the master oscillator frequenc of bearing plate 8, make the master oscillator frequenc of experiment gained identical with the master oscillator frequenc of field measurement by adjusting bed course 6, determine kind and the thickness of used bed course 6.
Step 5: select the intact sample of another piece 7, identical in bed course 6 and the step 4, by changing air forging hammer 13 to the horizontal range of sample 7, with step 1 uniform pressure under, by 13 actions of switch 12 control air forging hammer, make the peak value vibration velocity of the following bearing plate 8 that the blasting vibration instrument records identical with field measurement peak value vibration velocity, determine that air forging hammer 13 is to the distance of sample 7.
Step 6: select the intact sample of another piece 7, change compressed gas pressure by variable valve 10, and then the shock load of 13 pairs of following bearing plates 8 of change air forging hammer, simulate the different disturbing loads that different burst sizes produce, nonmetal sonic detection instrument records the acoustic velocity of sample 7, and the static strain tester is measured the strain value of sample 7.
Table two be
=0.3, the pressure of air forging hammer 13 is the following experimental data of being done of the situation of 0.5MPa.
Velocity of sound reduced rate
Computing formula be:
, wherein v is acoustic velocity after the disturbance,
Be initial velocity of wave.
After 50 disturbances: top
The middle part
The bottom
Step 7: utilize sonic method to set up the rock mass injury tolerance
, integrity factor
Harmony speed reduced rate
Between relation:
Just can calculate the rock mass injury tolerance by the sonic velocity change value
Step 8: the sample 7 that tests in the step 6 is put on the pressing machine, it is damaged by pressure, obtain the broken ring load of sample 7 this moment
,
-
It namely is the intensity drop-out value of sample 7.
Step 9: the strain value that records by experiment can calculate the elastic modulus of sample 7.
Table two
Table three
Table four
Table three is to be 0.3MPa at pressure, changes bed course 6, and the different master oscillator frequencs that obtain are after 50 disturbances, with the corresponding acoustic velocity of master oscillator frequenc.Table four is to be 0.5MPa at pressure, and air forging hammer 13 and sample 7 different distances produce different peak value vibration velocities, the acoustic velocity corresponding with the peak value vibration velocity.By table three and table four as can be seen, master oscillator frequenc and peak value vibration velocity have bigger influence to experimental result, so the present invention demarcates master oscillator frequenc and peak value vibration velocity before experiment, and more accurate simulated field real data.
Table five
Table five is contrast experiments of cushioned layer 6 experiments, traditional experiment and field measurement, and initial acoustic velocity is identical, is 0.3MPa with the perturbation pressure, and distance is all example mutually and calculates, and upper, middle and lower portion is respectively 1.667,1.807 and 1.899km/s, sample 7 injury tolerances
Table six:
Table six
Can clearly find out by table six, the adjusting of master oscillator frequenc produces very large influence to experimental result, the direct accurate analog case of influence experiment, thus the present invention utilize bed course 6 regulate in the experiment under the master oscillator frequenc of bearing plate 8, it identically with field measurement is necessary fully.
A spot of experiment is difficult to avoid data error, must be through a large amount of experiment, and the influence of rejecting accidentalia improves the directive function to site operation.Experimental data provided by the present invention is the sub-fraction with directive significance for extracting from a large amount of experimental datas only.
The above only is preferred embodiment of the present invention, is not to be the restriction of the present invention being made other form, and any those skilled in the art may utilize the technology contents of above-mentioned announcement to be changed or be modified as the equivalent embodiment of equivalent variations.But every technical solution of the present invention content that do not break away to any simple modification, equivalent variations and remodeling that above embodiment does, still belongs to the protection domain of technical solution of the present invention according to technical spirit of the present invention.
Claims (10)
1. accurate analogue means of blast disturbance shock load, comprise frame (15), be installed in upper and lower bearing plate (5,8) and measurement mechanism on the frame (15), sample (7) is fixed between the upper and lower bearing plate (5,8), it is characterized in that: also comprise for the dead load load maintainer that sample (7) is applied permanent load, be used for sample (7) is applied the disturbance load maintainer of disturbing load, and the master oscillator frequenc regulating device that is used for regulating sample (7) bottom of living in environment master oscillator frequenc.
2. the accurate analogue means of blast disturbance shock load according to claim 1, it is characterized in that: described disturbance load maintainer comprises air forging hammer (13), the air compressor machine (11) that is connected with air forging hammer (13) by compressed gas pipeline (9), air forging hammer (13) vertically is arranged on down the upper surface of bearing plate (8), and compressed gas pipeline (9) is provided with variable valve (10) and switch (12); Air forging hammer (13) can be adjusted it and descend bearing plate (8) to go up the position of relative sample (7).
3. the accurate analogue means of blast disturbance shock load according to claim 2 is characterized in that: be supported on frame (15) upper beam lower surface by vertical air forging hammer rigid support (14) on the described air forging hammer (13).
4. the accurate analogue means of blast disturbance shock load according to claim 1 and 2, it is characterized in that: described disturbance load maintainer applies disturbing load in a plurality of positions of sample (7) relatively at following bearing plate (8), and sample (7) produces different peak value vibration velocities.
5. the accurate analogue means of blast disturbance shock load according to claim 1, it is characterized in that: described dead load load maintainer comprises lever (1), depression bar (2) and counterweight (3), lever (1) one end is hinged on the frame (15), the other end is by pallet (4) carry counterweight (3), and depression bar (2) vertically is fixed between lever (1) and the last bearing plate (5).
6. the accurate analogue means of blast disturbance shock load according to claim 1, it is characterized in that: described master oscillator frequenc regulating device is bed course (6), bed course (6) is arranged between disturbance load maintainer and the frame (15).
7. the accurate analogue means of blast disturbance shock load according to claim 1, it is characterized in that: described master oscillator frequenc regulating device is bed course (6), bed course (6) is arranged between bearing plate (5) and the sample (7).
8. the accurate analogue means of blast disturbance shock load according to claim 1, it is characterized in that: described master oscillator frequenc regulating device is bed course (6), bed course (6) is arranged on down between bearing plate (8) and the sample (7).
9. according to the accurate analogue means of each described blast disturbance shock load of claim 6 ~ 8, it is characterized in that: described bed course (6) material is leather.
10. the accurate analogue means of blast disturbance shock load according to claim 1, it is characterized in that: described measurement mechanism comprises blasting vibration instrument, nonmetal sonic detection instrument and static strain tester.
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| CN201310245535.0A CN103335903B (en) | 2013-06-20 | 2013-06-20 | Blast disturbance shock load precise simulation device |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104792562A (en) * | 2015-04-27 | 2015-07-22 | 武汉理工大学 | Excavation transient unloading loose simulation experiment system for underground cavern structural plane |
| CN105223274A (en) * | 2015-09-29 | 2016-01-06 | 鞍钢集团矿业公司 | Utilize in hole the method for the detecting rock equivalent elastic modulus that drops hammer |
| WO2020228099A1 (en) * | 2019-05-16 | 2020-11-19 | 大连大学 | Device for acquiring health diagnosis monitoring data of nuclear power engineering structure in self-excited manner |
| CN115597988A (en) * | 2022-12-14 | 2023-01-13 | 湖南大学（Cn） | Pendulum bob test system with constant vertical pressure loading function |
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| US5739411A (en) * | 1995-11-13 | 1998-04-14 | Callaway Golf Company | Accelerated impact testing apparatus |
| CN1948945A (en) * | 2006-10-24 | 2007-04-18 | 中国矿业大学(北京) | Material flowing deformation disturbed effect testing system and testing method thereof |
| CN102788676A (en) * | 2012-09-03 | 2012-11-21 | 苏州世力源科技有限公司 | Pneumatic type high acceleration vertical impact table |
| US20130014558A1 (en) * | 2011-07-13 | 2013-01-17 | Hon Hai Precision Industry Co., Ltd. | Shock and impact testing device and method |
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2013
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5739411A (en) * | 1995-11-13 | 1998-04-14 | Callaway Golf Company | Accelerated impact testing apparatus |
| CN1948945A (en) * | 2006-10-24 | 2007-04-18 | 中国矿业大学(北京) | Material flowing deformation disturbed effect testing system and testing method thereof |
| US20130014558A1 (en) * | 2011-07-13 | 2013-01-17 | Hon Hai Precision Industry Co., Ltd. | Shock and impact testing device and method |
| CN102788676A (en) * | 2012-09-03 | 2012-11-21 | 苏州世力源科技有限公司 | Pneumatic type high acceleration vertical impact table |
Non-Patent Citations (1)
| Title |
|---|
| 张晓君 等: "岩爆倾向性巷（隧）道围岩破裂的试验研究", 《矿业研究与开发》, vol. 31, no. 4, 31 August 2011 (2011-08-31), pages 29 - 33 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104792562A (en) * | 2015-04-27 | 2015-07-22 | 武汉理工大学 | Excavation transient unloading loose simulation experiment system for underground cavern structural plane |
| CN104792562B (en) * | 2015-04-27 | 2017-07-11 | 武汉理工大学 | Underground chamber structural plane excavates transient unloading loose simulation experiment system |
| CN105223274A (en) * | 2015-09-29 | 2016-01-06 | 鞍钢集团矿业公司 | Utilize in hole the method for the detecting rock equivalent elastic modulus that drops hammer |
| WO2020228099A1 (en) * | 2019-05-16 | 2020-11-19 | 大连大学 | Device for acquiring health diagnosis monitoring data of nuclear power engineering structure in self-excited manner |
| CN115597988A (en) * | 2022-12-14 | 2023-01-13 | 湖南大学（Cn） | Pendulum bob test system with constant vertical pressure loading function |
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