1、Designation:D426205(Reapproved 2012)Standard Test Method forpH of Chemically Cleaned or Etched Concrete Surfaces1This standard is issued under the fixed designation D4262;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of la
2、st revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers procedures for determining theacidity or alkalinity of concrete surfaces prepared by chemicalcleaning
3、 or etching prior to coating.1.2 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations pr
4、ior to use.2.Terminology2.1 Definitions:2.1.1 pH,na measure of acidity or alkalinity of a solutionor surface,with neutrality represented by a value of 7,withincreasing acidity represented by smaller values,and withincreasing alkalinity represented by increasing values.3.Significance and Use3.1 Chemi
5、cal cleaning and etching is used to prepareconcrete for coating.3.2 Residual chemicals not removed by water rinsing mayadversely affect the performance and adhesion of coatingsapplied over prepared concrete surfaces.It is the intent of thistest method to determine that residual chemicals have beenre
6、moved by measuring the acidity or alkalinity of the finalrinsed surface.4.Apparatus4.1 The specific apparatus for each test is described inAnnex A1-Annex A3.5.Materials5.1 Potable Water,for rinsing chemically cleaned or etchedconcrete surfaces.5.2 Wet Concrete Surface,following the final water rinse
7、and before the rinse water has completely drained off thesurface.6.Procedure6.1 The preparatory actions for each alternative are de-scribed in Annex A1-Annex A3.6.2 At least two surface pH readings shall be taken for each500 square feet or portion thereof.Readings shall be taken atrandomly selected
8、locations immediately following the finalrinse and before all the rinse water has drained off the surface.6.3 The pH of the water used for rinsing shall be determinedto establish acceptance criteria.Readings shall be taken at thebeginning and end of the final rinse.6.4 Unless otherwise specified,tes
9、ts shall be conducted inaccordance with this procedure.7.Acceptance Criteria7.1 The pH readings following the final rinse shall not bemore than 1.0 pH lower or 2.0 higher than the pH of the rinsewater unless otherwise specified.8.Keywords8.1 etched concrete surface;pH1This test method is under the j
10、urisdiction of ASTM Committee D33 onProtective Coating and Lining Work for Power Generation Facilities and is the directresponsibility of Subcommittee D33.05 on Application and Surface Preparation.Current edition approved May 1,2012.Published May 2012.Originallyapproved in 1983.Last previous edition
11、 approved in 2005 as D4262 05.DOI:10.1520/D4262-05R12.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 ANNEXES(Mandatory Information)A1.pH TEST PAPER,TYPE 1A1.1 ApparatusA1.1.1 pH Test Paper,with a minimum range of 1 to 11 pHunits with a c
12、apability of measuring in increments of 0.5 pHunits.A1.2 ProcedureA1.2.1 Tear off a strip of test paper,wet with test water andafter the color develops,compare with color chart to determinepH.A2.pHYDRION INSTA-CHECK pH PENCILA2.1 ApparatusA2.1.1 pH Pencil,a marking instrument capable of measur-ing t
13、he surface pH from 0 to 13.A2.1.2 Color Comparison Chart.A2.2 ProcedureA2.2.1 Scratch the surface of the concrete with a metallicobject.A2.2.2 Moisten the surface with distilled water.A2.2.3 Mark over the scratch with pHydiron pencil.2A2.2.4 After 15 s,compare the color with the color com-parison ch
14、art.A2.2.5 The color produced is stable for several days.A3.pH METER3A3.1 ApparatusA3.1.1 Flat Electrode pH Pen,with a minimum range from0 pH to 14 pH units with the capability of measuring inincrements of 0.01 pH units.A3.2 ProcedureA3.2.1 Place the tip of the electrode into the test water.ThepH re
15、ading will appear in the display.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard.Users of this standard are expressly advised that determination of the validity of any such patent rights,and the riskof i
16、nfringement of such rights,are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised,either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters.Your comments will receive careful consideration at a meeting of theresponsible technical committee,which you m
