1、Designation:D297615Standard Test Method forpH of Peat Materials1This standard is issued under the fixed designation D2976;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the
2、 year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the electrometric measurementof the pH of peat materials,not soil.The standard formeasurement of pH in soil is Test Method D4972,nor does thiscover t
3、he measurement of pH for corrosion testing,which iscontained in Test Method G51.These standards are beingintentionally kept separate for clarity at the request(s)of thegoverning sub-committees.It is a means of expressing thedegree of acidity or alkalinity of peat material suspended inwater and 0.01
4、M calcium chloride solution.1.2 The values given in SI units are to be regarded as thestandard.1.3 The text of this standard references notes and footnoteswhich provide explanatory material.These notes and footnotesshall not be considered as requirements of the standard.1.4 All observed and calculat
5、ed values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.4.1 The procedures used to specify how data are collected/recorded or calculated,in this standard are regarded as theindustry standard.In addition,they are representative of thesignificant dig
6、its that generally should be retained.The proce-dures used do not consider material variation,purpose forobtaining the data,special purpose studies,or any consider-ations for the users objectives;and it is common practice toincrease or reduce significant digits of reported data to becommensurate wit
7、h these considerations.It is beyond the scopeof this standard to consider significant digits used in analysismethods for engineering design.1.5 This standard offers a set of instructions for performingone or more specific operations.This document cannot replaceeducation or experience and should be u
8、sed in conjunctionwith professional judgment.Not all aspects of this practice maybe applicable in all circumstances.This ASTM standard is notintended to represent or replace the standard of care by whichthe adequacy of a given professional service must be judged,nor should this document be applied w
9、ithout consideration ofa projects many unique aspects.The word”Standard”in thetitle of this document means only that the document has beenapproved though the ASTM consensus process.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is therespons
10、ibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil,Rock,and ContainedFluidsD1193 Specification for Reagent Water
11、D3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4972 Test Method for pH of SoilsD6026 Practice for Using Significant Digits in GeotechnicalDataG51 Test Method for Measuring pH of Soil for Use inCo
12、rrosion Testing3.Terminology3.1 Definitions:3.1.1 For definitions of common technical terms used in thisstandard,refer to Terminology D653.4.Summary of Test Method4.1 The electrometric measurement of the pH of peat insuspensions of water and calcium chloride solutions is madewith a potentiometer usi
13、ng an electrode system,calibrated withbuffers of known pH.5.Significance and Use5.1 pH measurements are made in water and in calciumchloride solution because the pH readings in water can be1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibili
14、ty of Subcommittee D18.22 on Soil as a Mediumfor Plant Growth.Current edition approved Nov.1,2015.Published December 2015.Originallyapproved in 1971.Last previous edition approved in 2004 as D2976-71(2004),which was withdrawn July 2015 and reinstated in November 2015.DOI:10.1520/D2976-15.2For refere
15、nced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright AS
16、TM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 modified by salts,such as fertilizer material,whereas theobserved pH in calcium chloride solution is virtually indepen-dent of the initial amount of salts present in the soil.pH valuesobtained in calcium chloride solution usually run about a 0.5 to0.8 pH unit lower than measurements in water due to release ofmore hydrogen ions by cation exchange.5.2 All water used for this test method must be ASTM T
