Designation:G187−12aStandardTestMethodforMeasurementofSoilResistivityUsingtheTwo-ElectrodeSoilBoxMethod1ThisstandardisissuedunderthefixeddesignationG187;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoverstheequipmentandproceduresforthemeasurementofsoilresistivity,forsamplesremovedfromtheground,foruseintheassessmentandcontrolofcorrosionofburiedstructures.1.2Proceduresallowforthistestmethodtobeusedinthefieldorinthelaboratory.1.3Thetestmethodproceduresarefortheresistivitymeasurementofsoilsamplesinthesaturatedconditionandintheas-receivedcondition.1.4ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.Soilresistivityvaluesarereportedinohm-centimeter.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesandtodeterminetheapplicabilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2D1193SpecificationforReagentWaterE691PracticeforConductinganInterlaboratoryStudytoDeterminethePrecisionofaTestMethodG57TestMethodforFieldMeasurementofSoilResistivityUsingtheWennerFour-ElectrodeMethodG193TerminologyandAcronymsRelatingtoCorrosion2.2UNSStandards:3UNSDesignationS30400&S30403UNSDesignationS31600&S316033.Terminology3.1Definitions:3.1.1Ohm’slaw,n—Therelationshipbetweentheelectro-motiveforce,thecurrent,andtheresistance.Mathematically:current=electromotiveforce/resistanceorI=E/R;where“I”ismeasuredinamperes,“E”involts,and“R”inohms.3.1.2resistivity(soil),n—Theelectricalresistancebetweenoppositefacesofaunitcubeofmaterial;thereciprocalofconductivity.3.1.3saturatedsoil,n—soilwhoseentiresoilporosityisfilledwithwater.3.1.4soilboxfactor,n—Afactorwhichisd...
