CN109188091B - The test method of electric resistance of soil nonlinear characteristic under a kind of different in moisture content - Google Patents
The test method of electric resistance of soil nonlinear characteristic under a kind of different in moisture content Download PDFInfo
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- 239000002689 soil Substances 0.000 title claims abstract description 135
- 238000010998 test method Methods 0.000 title claims abstract description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 50
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 47
- 238000012360 testing method Methods 0.000 claims abstract description 42
- 229910052802 copper Inorganic materials 0.000 claims abstract description 34
- 239000010949 copper Substances 0.000 claims abstract description 34
- 230000002262 irrigation Effects 0.000 claims description 12
- 238000003973 irrigation Methods 0.000 claims description 12
- 238000011084 recovery Methods 0.000 claims description 11
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- 238000004891 communication Methods 0.000 claims description 6
- 239000002131 composite material Substances 0.000 claims description 6
- 238000012937 correction Methods 0.000 claims description 3
- 239000012153 distilled water Substances 0.000 claims description 3
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- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
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Abstract
The test method of electric resistance of soil nonlinear characteristic under a kind of different in moisture content, test method includes building the test platform of electric resistance of soil nonlinear characteristic under different in moisture content；The impulse current generator output end of test platform is connected to the high-voltage end of divider, and the high-voltage end of divider is connected to left copper electrode；Right copper electrode is connected to earthing or grounding means by the ground terminal of impulse current generator；Current acquisition module is for measuring the electric current for flowing through left copper electrode and right copper electrode.It further include carrying out soil filling and water content setting, voltage and electric current of the measurement pedotheque in current water content and assessing electric resistance of soil nonlinear characteristic.The present invention accurately soil moisture control stable content can be conducive to study the relevance between moisture content and electric resistance of soil nonlinear characteristic in test setting value, and then effectively evaluate the nonlinear characteristic of soil test product resistance under the moisture content.
Description
Technical Field
The invention belongs to the technical field of power system grounding, and particularly relates to a method for testing the nonlinear characteristic of soil resistance under different moisture contents.
Background
When the power transmission line tower is struck by lightning, a very high potential can be generated on the tower body due to the existence of the tower grounding resistance, the tower is subjected to counterattack on the power transmission line due to the excessively high potential, further accidents such as tripping of the power transmission line are caused, and the stability and the reliability of a power system are reduced. The main function of the grounding device of the transmission line tower is to effectively discharge lightning current into the ground when the tower top or the lightning conductor is struck by lightning, so that the current flowing through the grounding device is mainly lightning impulse current. The lightning current amplitude is large, so that local breakdown of soil around the grounding body is easy to occur, the conductivity of the soil is increased, the resistivity of the soil is reduced, and in addition, when the electric field intensity generated by the scattered current in the soil exceeds the critical breakdown field intensity of the soil, a spark discharge process similar to air breakdown can occur in the soil around the grounding body. The nonlinear characteristic of the soil is beneficial to reducing the potential of each point on the grounding body and the potential difference between each point of the grounding body, and has obvious effect on reducing the tower top potential of the transmission line tower and the transient potential rise on the grounding network of the power generation station and the transformer substation. Therefore, the research on the lightning impulse characteristics of the grounding device of the power transmission and distribution tower has important significance for establishing an advanced and reliable power transmission and distribution network and a power supply system in an intelligent power grid and perfecting a power grid safety guarantee and defense system.
Because the grounding electrode of the power transmission line tower is buried in the soil, the impact characteristic of the grounding electrode is closely related to the impact characteristic of the soil around the grounding body. At present, the domestic research on the nonlinear characteristics of soil resistance mainly simulates the nonlinear process of soil resistance and the phenomenon of spark discharge through computer simulation, and the nonlinear characteristics of the soil resistance under the impact current are influenced by a plurality of factors, such as: the impact current amplitude, soil composition and structure, soil density, moisture content, temperature, external electric field intensity and the like, which cause the nonlinear resistance characteristic of the soil to become more complex when the high-frequency large impact current acts on the soil, wherein the soil moisture content often affects the nonlinear resistance characteristic of the soil to a great extent, and the impact transient characteristic of the whole grounding system is greatly affected. In order to accurately analyze the nonlinear condition of soil under impact and further analyze the impact transient characteristic of a grounding system, an intelligent measurement and control test platform is built to analyze the nonlinear characteristic of soil resistance under different moisture contents so as to evaluate the safety of a power transmission and distribution system. The method for testing the nonlinear characteristic of the soil resistance under different moisture contents is provided, the evaluation on the nonlinear characteristic of the soil resistance is realized, and theoretical support is provided for effectively designing the grounding device.
Disclosure of Invention
The invention aims to provide a method for testing the nonlinear characteristic of soil resistance under different moisture contents.
The technical scheme for realizing the purpose of the invention is as follows:
the first step is as follows: building a test platform of the nonlinear characteristic of the soil resistance under different moisture contents, wherein the test platform comprises a soil box; the upper panel of the soil box is provided with a slotted screw; the upper wall of the soil box is provided with a drip irrigation device; a left copper electrode is arranged on the left side wall of the soil box; the right side wall of the soil box is provided with a right copper electrode; the left copper electrode and the right copper electrode are both vertical discs and are tightly attached to the left side wall and the right side wall; the device outside the soil box comprises a cable joint, a grounding device, an impulse current generator, a voltage divider, a moisture analyzer, a digital controller, a current acquisition module, an upper computer, a high-voltage cable and a copper wire;
wherein: the first moisture sensor, the second moisture sensor, the third moisture sensor and the fourth moisture sensor are respectively connected to the input end of a moisture analyzer, and the output end of the moisture analyzer is respectively connected to the digital controller and the upper computer; the digital controller is connected to the drip irrigation device;
the output end of the impulse current generator is connected to the high-voltage end of the voltage divider, and the high-voltage end of the voltage divider is connected to the left copper electrode through a high-voltage cable and a cable joint; the right copper electrode is connected to the grounding end of the impulse current generator through a copper wire, and the grounding end is connected to a grounding device; the grounding end of the voltage divider is also connected to the grounding device, and the communication end of the voltage divider is connected to the upper computer; the communication end of the current acquisition module is connected to the upper computer, and the test end of the current acquisition module is connected to the copper wire;
the second step is that: soil filling and water content setting are carried out: loosening the slotted screw, opening the upper panel of the soil box, filling a soil sample to fill the soil in the whole soil box, and then covering the upper panel; first and second moisture sensorsThe device, the third moisture sensor and the fourth moisture sensor transmit acquired signals to the moisture analyzer, and the moisture analyzer calculates the average moisture content to monitor the moisture content of the soil sample in the soil box; setting the test water content to be H%, and if the water content exceeds the set upper limit HHAnd percent, disconnecting the drip irrigation device through a digital controller, and if the water content is lower than a set water content lower limit HLAnd percent, the drip irrigation device is started by the digital controller to uniformly and slowly inject distilled water into the soil, so that the water content of the soil sample in the soil box is within the error allowable range of the set water content H%;
the third step: measuring the voltage and current of the soil sample at the current water content of H%: starting an impulse current generator, measuring the voltage between the left copper electrode and the right copper electrode through a voltage divider and transmitting the voltage to an upper computer, and measuring the current flowing through the left copper electrode and the right copper electrode through a current acquisition module and transmitting the current to the upper computer;
the fourth step: evaluating the nonlinear characteristic of soil resistance: obtaining a full time domain R (t) wave curve of the nonlinear characteristic of the soil resistance through the voltage and the current obtained by an upper computer, and extracting a minimum value R (t) of the resistanceminMaximum resistance value R (t)maxThe fall time Deltat1And effective recovery time Δ t2The upper computer evaluates the nonlinear characteristic of the resistance of the soil according to the full time domain R (t) waveform curve and the current test moisture content;
calculating the average descending rate k of the soil under the impact current:
wherein R (t)minIs the minimum value of resistance in the R (t) waveform curve, R (t)maxIs the maximum value of resistance, Δ t, in the R (t) waveform curve1Denotes R (t) from the maximum value R (t)maxDown to a minimum value R (t)minThe time interval of (c);
calculation of R (t)minComposite evaluation factor q with k1：
Calculation of R (t)minAnd Δ t1Composite judgment factor q of2：
The minimum radius of curvature γ is calculated approximately:
wherein,
in the formula, tm∈[ta+0.1,tb)，taIs R (t)maxCorresponding time tbIs R (t)minCorresponding to the time, the above formula shows that in the time period of descending of the R (t) wave curve, t is within taStarting from +0.1 time, calculating the curvature radius corresponding to the time until t at intervals of 0.1 mu smT is greater than or equal tobAnd then the minimum curvature radius gamma can be calculated.
Calculating a correction factor k taking into account H and the minimum radius of curvature gamma1：
In the formula, H is the molecular part of the current water content H%, and gamma is the minimum curvature radius;
computing and judging remainder q3：
q3＝0.01747log(0.368Δt1+0.473Δt2-41.68)
-0.0343log(R(t)min+1.2075)
In the formula,. DELTA.t2Denotes R (t) from R (t)minRising to effective recovery resistance R (t)effThe time of (d); wherein
R(t)eff＝R(t)min+0.8(R(t)max-R(t)min)，R(t)effDenotes the minimum value of R (t) from the resistance R (t)minGradual recovery, when the recovery amount is 80% of the maximum decrease difference (R (t))max-R(t)min) A resistance value corresponding to the time;
calculating a soil resistance nonlinear characteristic evaluation factor q of the soil under the impact current and the moisture content:
q＝k1(q1+q2)+q3
when q belongs to (0, 0.25), the nonlinear characteristic of the characteristic soil resistance is weak, when q belongs to (0.25, 0.65), the nonlinear characteristic of the characteristic soil resistance is general, when q belongs to (0.65, 0.9), the nonlinear characteristic of the characteristic soil resistance is strong, and when q belongs to (0.9, 1), the nonlinear characteristic of the characteristic soil resistance is strong.
The fifth step: and (3) testing the nonlinear characteristics of the soil resistance under different moisture contents: setting different test water contents, and carrying out the nonlinear characteristic evaluation of the soil resistance under different water contents according to the third step and the fourth step of repeated tests under different set water contents.
The beneficial effect of the invention is that,
1) the method can accurately control the soil moisture content to be stabilized at a test set value, ensures that the full-time-domain resistance waveform curve corresponds to the test moisture content accurately, can accurately evaluate the nonlinear characteristic of the soil resistance, and is favorable for researching the correlation between the moisture content and the nonlinear characteristic of the soil resistance.
2) The test method is based on the full-time-domain resistance nonlinear characteristic waveform obtained by the upper computer, and can accurately represent the change rule of the resistance waveform curve, so that the nonlinear characteristic of the soil test sample resistance under the moisture content can be effectively evaluated.
3) The test platform is convenient to operate, safe and reliable.
Drawings
FIG. 1 is a schematic diagram of the general structure of the test platform according to the present invention;
FIG. 2 is a schematic view showing the construction of a soil box according to the present invention;
FIG. 3 is a flow chart of the test method of the present invention;
FIG. 4 is a graphical illustration of a soil resistance non-linear characteristic full time domain R (t) waveform.
Detailed Description
The following further describes embodiments of the present invention with reference to the drawings.
The test method of the invention comprises the following steps:
the first step is as follows: building a test platform for the nonlinear characteristic of the soil resistance under different moisture contents:
from fig. 1, fig. 2, it can be known that a test platform for nonlinear characteristics of soil resistance under different moisture contents is used for simulating nonlinear characteristics of soil resistance under different moisture contents, and the test platform includes: a soil box (06); a slotted screw (02) is arranged on the upper panel of the soil box (06); a drip irrigation device (08) is arranged on the upper wall of the soil box (06); a left copper electrode (05) is arranged on the left side wall of the soil box (06); the right side wall of the soil box (06) is provided with a right copper electrode (07); the left copper electrode (05) and the right copper electrode (07) are both vertical discs and are tightly attached to the left side wall and the right side wall; the left upper part, the right upper part, the left lower part and the right lower part of the soil box are respectively provided with a first moisture sensor (01a), a second moisture sensor (01b), a third moisture sensor (01c) and a fourth moisture sensor (01 d); the device outside the soil box (06) comprises a cable joint (03), a grounding device (11), an impact current generator (12), a voltage divider (13), a moisture analyzer (14), a digital controller (15), a current acquisition module (17), an upper computer (18), a high-voltage cable (19) and a copper wire (20);
wherein: the first moisture sensor (01a), the second moisture sensor (01b), the third moisture sensor (01c) and the fourth moisture sensor (01d) are respectively connected to the input end of a moisture analyzer (14), and the output end of the moisture analyzer (14) is respectively connected to the digital controller (15) and the upper computer (18); the digital controller (15) is connected to the drip irrigation device (08);
the output end of the impulse current generator (12) is connected to the high-voltage end of the voltage divider (13), and the high-voltage end of the voltage divider (13) is connected to the left copper electrode (05) through a high-voltage cable (19) and a cable joint (03); the right copper electrode (07) is connected to the grounding end of the impulse current generator (12) through a copper wire (20), and the grounding end is connected to the grounding device (11); the grounding end of the voltage divider (13) is also connected to the grounding device (11), and the communication end of the voltage divider (13) is connected to the upper computer (18); the communication end of the current acquisition module (17) is connected to the upper computer (18), and the test end of the current acquisition module (17) is connected to the copper wire (20);
the second step is that: soil filling and water content setting are carried out:
screwing off the straight-line groove screw (02), opening the upper panel of the soil box (06), filling a soil sample to fill the whole soil box (06), then covering the upper panel, and screwing down the straight-line groove screw (02); the first moisture sensor (01a), the second moisture sensor (01b), the third moisture sensor (01c) and the fourth moisture sensor (01d) transmit collected signals to the moisture analyzer (14), the average moisture content is calculated by the moisture analyzer (14), and the allowable error of the moisture content test is +/-0.5% so as to monitor the soil box (06)) The water content of the inner soil sample; setting the test water content to be H%, and if the water content exceeds the set upper limit HHPercent, the drip irrigation device (08) is disconnected through the digital controller (15), and if the water content is lower than the set lower limit H of the water contentLIf the water content is within the tolerance range of the set water content H%, the drip irrigation device (08) is started to uniformly and slowly inject distilled water into the soil through the digital controller (15), so that the water content of the soil sample in the soil box (06) is within the tolerance range of the set water content H%;
the third step: the voltage and current at the current water content H% of the soil sample were tested:
starting a surge current generator (12), measuring the voltage between the left copper electrode (05) and the right copper electrode (07) through a voltage divider (13) and transmitting the voltage to an upper computer (18); measuring the current flowing through the left copper electrode (05) and the right copper electrode (07) through a current acquisition module (17) and transmitting the current to an upper computer (18);
the fourth step: evaluating the nonlinear characteristic of soil resistance:
obtaining the voltage and current obtained by an upper computer (18) to obtain a soil resistance nonlinear characteristic full time domain R (t) wave curve, and extracting a resistance minimum value R (t)minMaximum resistance value R (t)maxThe fall time Deltat1And effective recovery time Δ t2The upper computer (18) evaluates the nonlinear resistance characteristic of the soil according to the R (t) wave curve and the current test moisture content;
calculating the average descending rate k of the soil under the impact current:
wherein R (t)min(in Ω) is the minimum resistance in the curve R (t), R (t)max(in Ω) is the maximum resistance, Δ t, in the R (t) waveform1(in. mu.s) denotes R (t) from the maximum value R (t)maxDown to a minimum value R (t)minThe time interval of (c).
Calculation of R (t)minComposite evaluation factor q with k1：
Calculation of R (t)minAnd Δ t1Composite judgment factor q of2：
The minimum radius of curvature γ is calculated approximately:
wherein,
in the formula, tm∈[ta+0.1,tb)，ta(in. mu.s) is R (t)maxCorresponding time tb(in. mu.s) is R (t)minCorresponding to the time, the above formula shows that in the time period of descending of the R (t) wave curve, t is within taStarting from +0.1 time, calculating the curvature radius corresponding to the time until t at intervals of 0.1 mu smT is greater than or equal tobAnd then the minimum curvature radius gamma can be calculated.
Calculating a correction factor k taking into account H and the minimum radius of curvature gamma1：
In the formula, H is the molecular part of the current water content H%, and gamma is the minimum curvature radius;
computing and judging remainder q3：
q3＝0.01747log(0.368Δt1+0.473Δt2-41.68)
-0.0343log(R(t)min+1.2075)
In the formula,. DELTA.t2(in. mu.s) denotes R (t) from R (t)minRising to effective recovery resistance R (t)effThe time of (d); wherein R (t)eff＝R(t)min+0.8(R(t)max-R(t)min)，R(t)effDenotes the minimum value of R (t) from the resistance R (t)minGradual recovery, when the recovery amount is 80% of the maximum decrease difference (R (t))max-R(t)min) A resistance value corresponding to the time;
calculating a soil resistance nonlinear characteristic evaluation factor q of the soil under the impact current and the moisture content:
q＝k1(q1+q2)+q3
when q belongs to (0, 0.25), the nonlinear characteristic of the characteristic soil resistance is weak, when q belongs to (0.25, 0.65), the nonlinear characteristic of the characteristic soil resistance is general, when q belongs to (0.65, 0.9), the nonlinear characteristic of the characteristic soil resistance is strong, and when q belongs to (0.9, 1), the nonlinear characteristic of the characteristic soil resistance is strong.
The fifth step: and (3) testing the nonlinear characteristics of the soil resistance under different moisture contents: and setting different test water contents, and evaluating the nonlinear characteristic of the soil resistance under different water contents. If the nonlinear characteristic of the soil resistance under three different water contents is to be tested, the three set water contents are respectively H1％、H2％、H3% by weight, setting the water content to H1% water content is set, and the water content is H according to the third step and the fourth step1% of the soil resistance non-linear characteristic test,water content H1After the% test is finished and after a certain time interval, the water content is respectively H2％、H3% soil resistance nonlinear characteristic test.
Claims (1)
1. A test method for the nonlinear characteristic of soil resistance under different moisture contents is characterized by comprising the following steps:
the first step is as follows: building a test platform of the nonlinear characteristic of the soil resistance under different moisture contents, wherein the test platform comprises a soil box (06); a slotted screw (02) is arranged on the upper panel of the soil box (06); a drip irrigation device (08) is arranged on the upper wall of the soil box (06); a left copper electrode (05) is arranged on the left side wall of the soil box (06); the right side wall of the soil box (06) is provided with a right copper electrode (07); the left copper electrode (05) and the right copper electrode (07) are both vertical discs and are tightly attached to the left side wall and the right side wall; the left upper part, the right upper part, the left lower part and the right lower part of the soil box are respectively provided with a first moisture sensor (01a), a second moisture sensor (01b), a third moisture sensor (01c) and a fourth moisture sensor (01 d); the device outside the soil box (06) comprises a cable joint (03), a grounding device (11), an impact current generator (12), a voltage divider (13), a moisture analyzer (14), a digital controller (15), a current acquisition module (17), an upper computer (18), a high-voltage cable (19) and a copper wire (20);
wherein: the first moisture sensor (01a), the second moisture sensor (01b), the third moisture sensor (01c) and the fourth moisture sensor (01d) are respectively connected to the input end of a moisture analyzer (14), and the output end of the moisture analyzer (14) is respectively connected to the digital controller (15) and the upper computer (18); the digital controller (15) is connected to the drip irrigation device (08);
the output end of the impulse current generator (12) is connected to the high-voltage end of the voltage divider (13), and the high-voltage end of the voltage divider (13) is connected to the left copper electrode (05) through a high-voltage cable (19) and a cable joint (03); the right copper electrode (07) is connected to the grounding end of the impulse current generator (12) through a copper wire (20), and the grounding end is connected to the grounding device (11); the grounding end of the voltage divider (13) is also connected to the grounding device (11), and the communication end of the voltage divider (13) is connected to the upper computer (18); the communication end of the current acquisition module (17) is connected to the upper computer (18), and the test end of the current acquisition module (17) is connected to the copper wire (20);
the second step is that: soil filling and water content setting are carried out: loosening the straight-line groove screw (02), opening the upper panel of the soil box (06), filling a soil sample to fill the whole soil box (06), then covering the upper panel, and screwing the straight-line groove screw (02); the first moisture sensor (01a), the second moisture sensor (01b), the third moisture sensor (01c) and the fourth moisture sensor (01d) transmit collected signals to the moisture analyzer (14), and the moisture analyzer (14) calculates the average moisture content to monitor the moisture content of a soil sample in the soil box (06); setting the test water content to be H%, and if the water content exceeds the set upper limit HHPercent, the drip irrigation device (08) is disconnected through the digital controller (15), and if the water content is lower than the set lower limit H of the water contentLPercent, then through a digital controller (15)) The drip irrigation device (08) is started to uniformly and slowly inject distilled water into the soil, so that the water content of the soil sample in the soil box (06) is within the error allowable range of the set water content H%;
the third step: the voltage and current at the current water content H% of the soil sample were tested: starting a surge current generator (12), measuring the voltage between the left copper electrode (05) and the right copper electrode (07) through a voltage divider (13) and transmitting the voltage to an upper computer (18);
measuring the current flowing through the left copper electrode (05) and the right copper electrode (07) through a current acquisition module (17) and transmitting the current to an upper computer (18);
the fourth step: evaluating the nonlinear characteristic of soil resistance: obtaining the voltage and current obtained by an upper computer (18) to obtain a soil resistance nonlinear characteristic full time domain R (t) wave curve, and extracting a resistance minimum value R (t)minMaximum resistance value R (t)maxThe fall time Deltat1And effective recovery time Δ t2The upper computer (18) evaluates the nonlinear resistance characteristic of the soil according to the full time domain R (t) waveform curve and the current test moisture content;
calculating the average descending rate k of the soil under the impact current:
wherein R (t)minIs the minimum value of resistance in the R (t) waveform curve, R (t)maxIs the maximum value of resistance, Δ t, in the R (t) waveform curve1Denotes R (t) from the maximum value R (t)maxDown to a minimum value R (t)minThe time interval of (c);
calculation of R (t)minComposite evaluation factor q with k1：
Calculation of R (t)minAnd Δ t1Composite judgment factor q of2：
The minimum radius of curvature γ is calculated approximately:
wherein,
in the formula, tm∈[ta+0.1,tb)，taIs R (t)maxCorresponding time tbIs R (t)minCorresponding to the time, the above formula shows that in the time period of descending of the R (t) wave curve, t is within taStarting from +0.1 time, calculating the curvature radius corresponding to the time until t at intervals of 0.1 mu smT is greater than or equal tobAnd (4) ending, and calculating the minimum curvature radius gamma;
calculating a correction factor k taking into account H and the minimum radius of curvature gamma1：
In the formula, H is the molecular part of the current water content H%, and gamma is the minimum curvature radius;
computing and judging remainder q3：
q3＝0.01747log(0.368Δt1+0.473Δt2-41.68)
-0.0343log(R(t)min+1.2075)
In the formula,. DELTA.t2Denotes R (t) from R (t)minRising to effective recovery resistance R (t)effThe time of (d); wherein R (t)eff＝R(t)min+0.8(R(t)max-R(t)min)，R(t)effDenotes the minimum value of R (t) from the resistance R (t)minGradually recovering when the recovery amount is 80% of the maximum reduction difference(R(t)max-R(t)min) A resistance value corresponding to the time;
calculating a soil resistance nonlinear characteristic evaluation factor q of the soil under the impact current and the moisture content:
q＝k1(q1+q2)+q3
when q belongs to (0, 0.25), the nonlinear characteristic of the characteristic soil resistance is weaker, when q belongs to (0.25, 0.65), the nonlinear characteristic of the characteristic soil resistance is general, when q belongs to (0.65, 0.9), the nonlinear characteristic of the characteristic soil resistance is stronger, and when q belongs to (0.9, 1), the nonlinear characteristic of the characteristic soil resistance is extremely strong;
the fifth step: and (3) testing the nonlinear characteristics of the soil resistance under different moisture contents: setting different test water contents, and carrying out the nonlinear characteristic evaluation of the soil resistance under different water contents according to the third step and the fourth step of repeated tests under different set water contents.
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|---|---|---|---|---|
| CN104090001A (en) * | 2014-07-29 | 2014-10-08 | 太原理工大学 | Method for evaluating corrosivity of polluted soil |
| CN106546711A (en) * | 2017-01-17 | 2017-03-29 | 西安科技大学 | The relational model construction method of frozen soil resistivity and temperature and content of unfrozen water in frozen earth |
| CN107422239A (en) * | 2017-09-27 | 2017-12-01 | 重庆大学 | The more dash current discharge test device and methods of soil |
| CN107782976A (en) * | 2017-12-01 | 2018-03-09 | 广东电网有限责任公司佛山供电局 | A kind of impulse earthed resistance measuring method of meter and soil ion concentration |
-
2018
- 2018-08-13 CN CN201810912703.XA patent/CN109188091B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104090001A (en) * | 2014-07-29 | 2014-10-08 | 太原理工大学 | Method for evaluating corrosivity of polluted soil |
| CN106546711A (en) * | 2017-01-17 | 2017-03-29 | 西安科技大学 | The relational model construction method of frozen soil resistivity and temperature and content of unfrozen water in frozen earth |
| CN107422239A (en) * | 2017-09-27 | 2017-12-01 | 重庆大学 | The more dash current discharge test device and methods of soil |
| CN107782976A (en) * | 2017-12-01 | 2018-03-09 | 广东电网有限责任公司佛山供电局 | A kind of impulse earthed resistance measuring method of meter and soil ion concentration |
Non-Patent Citations (2)
| Title |
|---|
| 同轴圆柱形电极下土壤冲击特性的试验研究;陈名铭 等;《电网技术》;20130831;第37卷(第8期);第1-6页 |
| 温度对土壤电阻率影响的研究;曹晓斌 等;《电工技术学报》;20070930;第22卷(第9期);第2291-2296页 |
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