CN110907320A - Laboratory simulation pavement dust production and detection method - Google Patents
Laboratory simulation pavement dust production and detection method Download PDFInfo
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- CN110907320A CN110907320A CN201911153670.6A CN201911153670A CN110907320A CN 110907320 A CN110907320 A CN 110907320A CN 201911153670 A CN201911153670 A CN 201911153670A CN 110907320 A CN110907320 A CN 110907320A
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- 239000000428 dust Substances 0.000 title claims abstract description 49
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 20
- 238000001514 detection method Methods 0.000 title claims description 21
- 238000004088 simulation Methods 0.000 title description 4
- 238000012360 testing method Methods 0.000 claims abstract description 77
- 239000002245 particle Substances 0.000 claims abstract description 26
- 239000000463 material Substances 0.000 claims abstract description 18
- 238000001035 drying Methods 0.000 claims abstract description 10
- 238000000034 method Methods 0.000 claims abstract description 9
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 7
- 238000005303 weighing Methods 0.000 claims abstract description 7
- 238000005096 rolling process Methods 0.000 claims abstract description 6
- 238000004140 cleaning Methods 0.000 claims abstract description 4
- 239000004575 stone Substances 0.000 claims description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 13
- 239000003245 coal Substances 0.000 claims description 12
- 239000002689 soil Substances 0.000 claims description 7
- 238000005507 spraying Methods 0.000 claims description 6
- 238000007789 sealing Methods 0.000 claims description 5
- 239000004744 fabric Substances 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims description 3
- 239000011435 rock Substances 0.000 claims description 3
- 238000010410 dusting Methods 0.000 claims 8
- 230000000694 effects Effects 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
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Abstract
The invention discloses a method for simulating road surface dust production and detecting in a laboratory, which comprises the following steps: the device comprises a sealed box body, a transverse plate, a test die, a variable load test vehicle, a particle counter, a dust collector and a fan; further comprising: step one, determining actual parameters of a measured road surface; step two, mixing and drying the materials for manufacturing the simulated pavement, weighing, cleaning and drying the test mold, and weighing the test mold; filling the material in the second step in a test mold to manufacture a test piece; step four, starting the particle counter and the variable load test vehicle in sequence; step five, restarting the fan; step six, starting a dust collector; step seven, stopping the equipment in the step four to the step six; and step eight, changing the humidity, the temperature or the content of the dust-settling agent in the box body, and repeatedly executing the step two to the step seven. The invention can more conveniently and efficiently detect the factors influencing the generation of the road dust in a laboratory by simulating the actual state of the road surface and combining with the rolling of the wheels of the variable load test vehicle.
Description
Technical Field
The invention relates to the field of detection, in particular to a laboratory simulation pavement dust production and detection method.
Background
Along with the increasing of the production intensity of mines in China, the mechanization level is continuously improved, so that the dust yield of transportation equipment is increased day by day, and the method is the largest dust pollution source of strip mines. Most of the existing dust detection methods are field detection, and if the dust production of different roads is compared and analyzed, the operation is inconvenient, so that the process is time-consuming and labor-consuming, and the working efficiency is low. In addition, if the effect of sprinkling water or a certain dust suppressant on the road surface is to be tested, the detection can be implemented after a large number of vehicles pass through the road surface, and although the detection effect is more real, the operation is complex, and time and labor are wasted.
Disclosure of Invention
In order to solve the problems in the prior art and make up the defect that a laboratory cannot simulate and detect the condition of the pavement dust, the method for simulating pavement dust production and detecting in the laboratory is provided.
In order to achieve the purpose, the invention adopts the following technical scheme:
a laboratory simulation pavement dust production and detection method comprises the following steps: sealing the box body; a transverse plate is fixed at the inner bottom of the box body; a test die and a variable load test vehicle which linearly reciprocates are sequentially arranged on the transverse plate; the wheels of the variable load test vehicle are in contact with a test piece in the test mould; the side edge of the test piece is communicated with the particle counter; the side wall of the box body is provided with a dust collector and a fan;
further comprising:
step one, determining actual parameters of a measured road surface;
step two, mixing and drying the materials for manufacturing the simulated pavement for later use, cleaning and drying a test mold, and weighing the test mold to obtain a mass M3;
step three, manufacturing a test piece by using the material in the step two in a test mold, and recording the total mass of the test mold and the test piece as M1;
step four, starting a particle counter and a variable load test vehicle in sequence, and recording the parameter N1 of the dust particles;
step five, starting the fan again, and recording the parameter N2 of the dust particles;
step six, starting a dust collector, and recording the parameter N3 of dust particles;
step seven, stopping the equipment in the steps four to six, drying the test mold and the test piece, and weighing the total mass of the test mold and the test piece again as M2; calculating the dust yield Q of the simulated pavement;
and step eight, changing the humidity and the temperature of the test piece in the box body or the content of the dust-settling agent, and repeatedly executing the step two to the step seven.
Further, the actual parameters in the step one include: water content, soil-rock ratio, dry density and site wind speed.
Wherein, the road surface in step one includes: crushed stone pavement, mud pavement or coal pavement.
Further, the material of the gravel road comprises: soil: the stone mixing proportion is 10:40:50 or 10:60:30 or 12:58:30
Still further, the material of dirt road surface is soil.
Further, the material of the coal pavement comprises coal or coal gangue.
The step of manufacturing the test piece in the third step comprises the following steps:
step a, paving main-layer stones according to the pavement thickness and a loose paving coefficient of 1.3-1.4, spraying water in a proper amount, pressing to be basically stable, and then spraying a large amount of water until the stones are fully compacted;
step b, then, caulking stone is scattered, and water is sprayed for rolling;
and c, uniformly scattering 5-15 mm of the sealing fabric until no wheel marks appear on the surface.
Further, the dust production amount Q = (M)2-M3）/（M1-M3）。
And furthermore, when the humidity, the temperature or the content of the dust-settling agent in the step eight is changed, a cabinet door of the box body needs to be opened, and the test die and the test piece are integrally replaced.
Compared with the prior art, the invention has the following beneficial effects: the invention can more conveniently and efficiently detect the factors influencing the generation of the road dust in a laboratory by simulating the actual state of the road, and can restore the actual condition of the road in the maximum proportion under the rolling of the wheels of the variable load test vehicle.
Drawings
FIG. 1 is a schematic view of the apparatus of the present invention.
In the figure, 1, a dust collector; 2. a box body; 3. a cabinet door; 4. a variable load test vehicle; 5. a fan; 6. a particle counter; 7. a transverse plate; 8. testing a mold; 9. a test piece; 10. and (7) wheels.
Detailed Description
The invention is described in further detail below with reference to the figures and specific examples.
As shown in fig. 1, a method for dust generation and detection on a laboratory simulated pavement comprises the following steps: sealing the box body 2; a transverse plate 7 is fixed at the inner bottom of the box body 2; a test die 8 and a variable load test vehicle 4 which linearly reciprocates are sequentially arranged on the transverse plate 7, and the variable load implementation mode can be realized by adding a balancing weight; the wheels 10 of the variable load test vehicle 4 are in contact with the test piece 9 in the test mold 8; the rolling of the wheel 10 is intended to simulate traffic on the road. In order to detect the number of instances in the box body 2, the side edge of the test piece 9 is communicated with the particle counter 6; moreover, a dust collector 1 and a fan 5 are arranged on the side wall of the box body 2; the dust collector 1 is used for preventing dust from falling back and avoiding the influence of secondary dust on the detection of dust particles, and the wind speed of the fan 5 is used for providing simulated outdoor wind and simulating the wind speed of a site. When detecting, the method also comprises the following steps:
step one, determining actual parameters of a measured road surface; these actual parameters include: water content, soil-rock ratio, dry density and site wind speed. The road surface herein may include: crushed stone pavement, mud pavement or coal pavement. Wherein, the material of rubble road surface includes, ash: soil: the stone is 10:40:50 or 10:60:30 or 12:58: 30; the material of the dirt road surface is soil; the material of the coal pavement comprises coal or coal gangue.
Step two, mixing and drying the materials for manufacturing the simulated pavement for later use, cleaning and drying the test mold 8, weighing the mass as M3(ii) a Wherein the gravel pavement material comprises, ash: soil: the stone mixing ratio is 10:40:50 or 10:60:30 or 12:58: 30; the stone is above grade 3.
Step three, manufacturing a test piece 9 in the test mold 8 by using the material in the step two, and recording the total mass of the test mold 8 and the test piece 9 as M1; the compacted thickness of the test piece 9 is 8-16 cm. Wherein, the step of making the test piece 9 comprises:
step a, paving main-layer stones according to the pavement thickness and a loose paving coefficient of 1.3-1.4, spraying water in a proper amount, pressing to be basically stable, and then spraying a large amount of water until the stones are fully compacted;
step b, then, caulking stone is scattered, and water is sprayed for rolling;
and c, uniformly scattering 5-15 mm of the sealing fabric until no wheel marks appear on the surface. And placing the manufactured test piece 9 and the test mold 8 on the transverse plate 7.
In the fourth step, the particle counter 6 and the variable load test vehicle 4 are started in sequence, and the parameter N of the dust particles is recorded1(ii) a Parameter N1The method comprises the following steps: the particle number of the road surface and the diameter range of the flying particles are simulated in a windless environment.
Step five, restarting the fan 5, and recording the parameter N of the dust particles2(ii) a Likewise, parameter N2The content of step four is also included. For detecting the effect of wind speed on particle diameter and number.
In order to avoid the influence of secondary dust emission on the experimental effect, in step six, the dust collector 1 is started, and the parameter N of the dust particles is recorded3(ii) a Likewise, parameter N3The number of particles on the road surface and the diameter range of the flying particles.
Through the detection result, curves of dust particle changes under different conditions can be drawn.
In the seventh step, the equipment in the fourth to sixth steps is stopped, the test mold 8 and the test piece 9 are dried, and the total mass of the test mold 8 and the test piece 9 is weighed again and recorded as M2; calculating the dust yield Q of the simulated pavement; the dust yield Q = (M)2-M3）/（M1-M3）。
In order to improve the detection accuracy and increase a comparison experiment for investigating the influence of other factors on the road surface to generate dust particles, step eight, changing the humidity, the temperature or the content of the dust-settling agent of the test piece 9 in the box body 2, and repeatedly executing the steps two to seven. The mode of changing humidity, temperature or dust fall agent content parameter can be, opens the cabinet door 3 of box 2, changes the environment in the box 2, will try mould 8 and test piece 9 whole replacement again, because dust yield Q is the proportional relation, the concrete quality of test piece 9 at every turn also can be different, does not influence actual testing result.
Claims (9)
1. A method for simulating road surface dust production and detecting in a laboratory is characterized in that:
the method comprises the following steps: a sealed box body (2);
a transverse plate (7) is fixed at the inner bottom of the box body (2); a test die (8) and a variable load test vehicle (4) which moves in a linear reciprocating manner are sequentially arranged on the transverse plate (7); the wheels (10) of the variable load test vehicle (4) are in contact with the test piece (9) in the test mold (8);
the side edge of the test piece (9) is communicated with the particle counter (6);
the side wall of the box body (2) is provided with a dust collector (1) and a fan (5);
further comprising:
step one, determining actual parameters of a measured road surface;
step two, mixing and drying the materials for manufacturing the simulated pavement for later use, cleaning and drying the test mold (8), weighing the mass as M3；
Step three, manufacturing a test piece (9) in the test mold (8) by using the material in the step two, and recording the total mass of the test mold (8) and the test piece (9) as M1；
Step four, starting the particle counter (6) and the variable load test vehicle (4) in sequence, and recording the parameter N of the dust particles1；
Step five, restarting the fan (5) and recording the parameter N of the dust particles2；
Sixthly, starting the dust collector (1) and recording the parameter N of the dust particles3；
Step seven, stopping the equipment in the steps four to six, drying the test mold (8) and the test piece (9), weighing the total mass of the test mold (8) and the test piece (9) again and recording the total mass as M2(ii) a Calculating the dust yield Q of the simulated pavement;
and step eight, changing the humidity and the temperature of the test piece (9) in the box body (2) or the content of the dust-settling agent, and repeatedly executing the step two to the step seven.
2. The laboratory simulated pavement dusting and detection method of claim 1, further comprising: the actual parameters in the first step include: water content, soil-rock ratio, dry density and site wind speed.
3. The laboratory simulated pavement dusting and detection method of claim 1, further comprising: the pavement in the first step comprises: crushed stone pavement, mud pavement or coal pavement.
4. The laboratory simulated pavement dusting and detection method of claim 3, characterized in that: the materials of the gravel pavement comprise: soil: the stone mixing ratio is 10:40:50 or 10:60:30 or 12:58: 30.
5. The laboratory simulated pavement dusting and detection method of claim 3, characterized in that: the material of the dirt road surface is soil.
6. The laboratory simulated pavement dusting and detection method of claim 3, characterized in that: the material of the coal pavement comprises coal or coal gangue.
7. The laboratory simulated pavement dusting and detection method of claim 1, further comprising: the step three of manufacturing the test piece (9) comprises the following steps:
step a, paving main-layer stones according to the pavement thickness and a loose paving coefficient of 1.3-1.4, spraying water in a proper amount, pressing to be basically stable, and then spraying a large amount of water until the stones are fully compacted;
step b, then, caulking stone is scattered, and water is sprayed for rolling;
and c, uniformly scattering 5-15 mm of the sealing fabric until no wheel marks appear on the surface.
8. The laboratory simulated pavement dusting and detection method of claim 1, further comprising: the dust yield Q = (M)2-M3）/（M1-M3）。
9. The laboratory simulated pavement dusting and detection method of claim 1, further comprising: and (3) when the humidity, the temperature or the content of the dust-settling agent in the step eight is changed, opening the cabinet door (3) of the box body (2), and integrally replacing the test die (8) and the test piece (9).
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| CN201911153670.6A CN110907320B (en) | 2019-11-22 | 2019-11-22 | Detection method for simulating road surface dust generation in laboratory |
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| CN110907320B CN110907320B (en) | 2021-01-15 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112213243A (en) * | 2020-09-25 | 2021-01-12 | 桂林电子科技大学 | Dust emission degree detection system, dust emission degree detection method, and computer storage medium |
| CN112986066A (en) * | 2021-02-08 | 2021-06-18 | 清华大学 | Experimental device for be used for studying dust particle resuspension law |
| CN113804391A (en) * | 2021-06-04 | 2021-12-17 | 中国神华能源股份有限公司哈尔乌素露天煤矿研究院 | Development method of simulated strip mine road dust suppressant based on raise dust control test |
| CN114659806A (en) * | 2022-03-29 | 2022-06-24 | 重庆长安汽车股份有限公司 | Dust road for whole vehicle road test and test method |
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| CN114659806A (en) * | 2022-03-29 | 2022-06-24 | 重庆长安汽车股份有限公司 | Dust road for whole vehicle road test and test method |
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