ASTM G187-12a
(Test Method)Standard Test Method for Measurement of Soil Resistivity Using the Two-Electrode Soil Box Method
Standard Test Method for Measurement of Soil Resistivity Using the Two-Electrode Soil Box Method
SIGNIFICANCE AND USE
5.1 The resistivity of the surrounding soil environment is a factor in the corrosion of underground structures. High resistivity soils are generally not as corrosive as low resistivity soils. The resistivity of the soil is one of many factors that influence the service life of a buried structure. Soil resistivity may affect the material selection and the location of a structure.5
5.2 Soil resistivity is of particular importance and interest in the corrosion process because it is basic in the analysis of corrosion problems and the design of corrective measures.
5.3 The test method is focused to provide an accurate, expeditious measurement of soil resistivity to assist in the determination of a soil’s corrosive nature. Test Method G57 emphasizes an in situ measurement commonly utilized in the design of a buried structures’ corrosion control (cathodic protection systems’ ground bed design, and so forth). The two-electrode soil box method often compliments the four-pin, in situ soil resistivity method.
5.4 The saturated soil resistivity determined by this test method does not necessarily indicate the minimum soil resistivity.
SCOPE
1.1 This test method covers the equipment and procedures for the measurement of soil resistivity, for samples removed from the ground, for use in the assessment and control of corrosion of buried structures.
1.2 Procedures allow for this test method to be used in the field or in the laboratory.
1.3 The test method procedures are for the resistivity measurement of soil samples in the saturated condition and in the as-received condition.
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. Soil resistivity values are reported in ohm-centimeter.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use.
General Information
Relations
Buy Standard
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: G187 − 12a
Standard Test Method for
Measurement of Soil Resistivity Using the Two-Electrode
1
Soil Box Method
This standard is issued under the fixed designation G187; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Terminology
1.1 This test method covers the equipment and procedures 3.1 Definitions:
for the measurement of soil resistivity, for samples removed 3.1.1 Ohm’s law, n—The relationship between the electro-
from the ground, for use in the assessment and control of motive force, the current, and the resistance. Mathematically:
corrosion of buried structures. current = electromotive force/resistance or I = E/R; where “I”
is measured in amperes, “E” in volts, and “R” in ohms.
1.2 Procedures allow for this test method to be used in the
3.1.2 resistivity (soil), n—The electrical resistance between
field or in the laboratory.
opposite faces of a unit cube of material; the reciprocal of
1.3 The test method procedures are for the resistivity
conductivity.
measurement of soil samples in the saturated condition and in
3.1.3 saturated soil, n—soil whose entire soil porosity is
the as-received condition.
filled with water.
1.4 The values stated in SI units are to be regarded as the
3.1.4 soil box factor, n—A factor which is determined by a
standard. The values given in parentheses are for information
two-electrode soil box’s internal dimensions (cross sectional
only. Soil resistivity values are reported in ohm-centimeter.
area/distance between electrode plates). The soil box factor is
1.5 This standard does not purport to address all of the
multipliedbythemeasuredresistanceofasubstanceinthesoil
safety concerns, if any, associated with its use. It is the
box to obtain that substance’s resistivity.
responsibility of the user of this standard to establish appro-
3.1.5 soil resistance meter, n—An instrument capable of
priate safety and health practices and to determine the
measuring soil resistance.
applicability of regulatory limitations prior to use.
3.1.6 two-electrode soil box, n—Anon-conductivecontainer
2. Referenced Documents
ofknowninternaldimensionswithtwoendplateelectrodesfor
2
measuring a substance’s resistivity.
2.1 ASTM Standards:
D1193Specification for Reagent Water
3.2 The terminology used herein, if not specifically defined
E691Practice for Conducting an Interlaboratory Study to
otherwise, shall be in accordance with Terminology G193.
Determine the Precision of a Test Method
Definitions provided herein and not given in Terminology
G57Test Method for Field Measurement of Soil Resistivity
G193 are limited only to this standard.
Using the Wenner Four-Electrode Method
G193Terminology and Acronyms Relating to Corrosion 4. Summary of Test Method
3
2.2 UNS Standards:
4.1 The two-electrode soil box method is predicated on
UNS Designation S30400 & S30403
measuring the resistance between two opposite faces of a box
UNS Designation S31600 & S31603
containing a substance or solution. That resistance measure-
ment through the substance being tested is then converted to
resistivity based on the conversion formula of Eq 1.
1
This test method is under the jurisdiction of ASTM Committee G01 on
Corrosion of Metals and is the direct responsibility of Subcommittee G01.10 on
Corrosion in Soils.
Current edition approved Nov. 1, 2012. Published March 2013. Originally
approved in 2005. Last previous edition approved in 2012 as G187–12. DOI:
10.1520/G0187-12A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
3
UNS (Unified Numbering System) was developed jointly by ASTM Interna-
tional and SAE International.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
---------------------- Page: 1 ----------------------
G187 − 12a
FIG. 1 Typical Connections for Use of Soil Box with Soil Resistance Meter
4.2 A voltage is applied to the opposing electrodes and the 5.3 The test method is focused to provide an accurate,
resultingcurrentismeasured.Ohm’slawrevealstheresistance. expeditious measurement of soil resistivity to assist in the
The resistivity, ρ, is then: determination of a soil’s corrosive nature. Test Method G57
emphasizes an in situ measurement commonly utilized in the
ρ ~ohm 2 cm! 5 AR/d (1)
design of a buried structures’ corrosion control (cathodic
where:
protection systems’ ground bed design, and so forth). The
2
A = exposed area of one
...
This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: G187 − 12 G187 − 12a
Standard Test Method for
Measurement of Soil Resistivity Using the Two-Electrode
1
Soil Box Method
This standard is issued under the fixed designation G187; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the equipment and procedures for the measurement of soil resistivity, for samples removed from
the ground, for use in the assessment and control of corrosion of buried structures.
1.2 Procedures allow for this test method to be used in the field or in the laboratory.
1.3 The test method procedures are for the resistivity measurement of soil samples in the saturated condition and in the
as-received condition.
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
Soil resistivity values are reported in ohm-centimeter.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
D1193 Specification for Reagent Water
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
G57 Test Method for Field Measurement of Soil Resistivity Using the Wenner Four-Electrode Method
G193 Terminology and Acronyms Relating to Corrosion
3
2.2 UNS Standards:
UNS Designation S30400 & S30403
UNS Designation S31600 & S31603
3. Terminology
3.1 Definitions:
3.1.1 Ohm’s law, n—The relationship between the electromotive force, the current, and the resistance. Mathematically: current
= electromotive force/resistance or I = E/R; where “I” is measured in amperes, “E” in volts, and “R” in ohms.
3.1.2 resistivity (soil), n—The electrical resistance between opposite faces of a unit cube of material; the reciprocal of
conductivity.
3.1.3 saturated soil, n—soil whose entire soil porosity is filled with water.
3.1.4 soil box factor, n—A factor which is determined by a two-electrode soil box’s internal dimensions (cross sectional
area/distance between electrode plates). The soil box factor is multiplied by the measured resistance of a substance in the soil box
to obtain that substance’s resistivity.
3.1.5 soil resistance meter, n—An instrument capable of measuring soil resistance.
1
This test method is under the jurisdiction of ASTM Committee G01 on Corrosion of Metals and is the direct responsibility of Subcommittee G01.10 on Corrosion in
Soils.
Current edition approved May 1, 2012Nov. 1, 2012. Published November 2012March 2013. Originally approved in 2005. Last previous edition approved in 20052012
as G187–05.–12. DOI: 10.1520/G0187-12.10.1520/G0187-12A.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
UNS (Unified Numbering System) was developed jointly by ASTM International and SAE International.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
---------------------- Page: 1 ----------------------
G187 − 12a
3.1.6 two-electrode soil box, n—A non-conductive container of known internal dimensions with two end plate electrodes for
measuring a substance’s resistivity.
3.2 The terminology used herein, if not specifically defined otherwise, shall be in accordance with Terminology G193.
Definitions provided herein and not given in Terminology G193 are limited only to this standard.
4. Summary of Test Method
4.1 The two-electrode soil box method is predicated on measuring the resistance between two opposite faces of a box containing
a substance or solution. That resistance measurement through the substance being tested is then converted to resistivity based on
the conversion formula of Eq 1.
2
---------------------- Page: 2 ----------------------
G187 − 12a
4.2 A voltage is applied to the opposing electrodes and the resulting current is measured. Ohm’s law reveals the resistance. The
resistivity, ρ, is then:
ρ ohm 2 cm 5 AR/d (1)
~ !
where:
2
A = expose
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.