1、Designation: C823/C823M 12 (Reapproved 2017)Standard Practice forExamination and Sampling of HardenedConcrete in Constructions1This standard is issued under the fixed designation C823/C823M; the number immediately following the designation indicates the yearof original adoption or, in the case of re
2、vision, 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. Scope1.1 This practice outlines procedures for visual examinationand sampling of hardened concrete in const
3、ructions. Referenceis made to the examination and sampling of concrete inprefabricated building units, precast products, and laboratoryspecimens.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equ
4、ivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user
5、of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Pr
6、inciples for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C42/C42M Test Method for Obtaining and Testing DrilledCores and Sawed Beams of ConcreteC125
7、 Terminology Relating to Concrete and Concrete Ag-gregatesC215 Test Method for Fundamental Transverse,Longitudinal, and Torsional Resonant Frequencies ofConcrete SpecimensC295 Guide for Petrographic Examination of Aggregates forConcreteC457 Test Method for Microscopical Determination of Pa-rameters
8、of the Air-Void System in Hardened ConcreteC597 Test Method for Pulse Velocity Through ConcreteC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC856 Practice for Petrographic Examination of HardenedConcreteE105 Practice for Probability Sampling of M
9、aterialsE122 Practice for Calculating Sample Size to Estimate, WithSpecified Precision, the Average for a Characteristic of aLot or ProcessE141 Practice for Acceptance of Evidence Based on theResults of Probability Sampling3. Terminology3.1 DefinitionsFor definitions of terms used in thispractice, r
10、efer to Terminology C125.3.2 Definitions of Terms Specific to This Standard:3.2.1 concrete constructions, nany object, unit, or struc-ture that has been built of hydraulic cement concrete.3.2.2 category of concrete, na specified level of quality inconcrete that is observed to be in a definable range
11、 of conditionas a result of service or test exposure, as distinguished fromconcrete in the same or related constructions that is either ofdiffering specified quality or of the same specified quality butin observably different condition at the time of examination. Itis also used to refer to concrete
12、having a certain attribute orattributes. (see the Sampling Plan Section).4. Significance and Use4.1 The examination may provide a basis for laying out insitu testing of the concrete.4.2 The sampling can provide materials for petrographicexamination, in accordance with Practice C856, chemical orphysi
13、cal analytical procedures, or any of a wide variety ofdestructive or nondestructive tests to determine physical,mechanical, or structural properties of the concrete.4.3 The results of examination and sampling carried out inaccordance with this practice may be used for a variety of1This practice is u
14、nder the jurisdiction of ASTM Committee C09 on Concreteand Concrete Aggregates, and is the direct responsibility of Subcommittee C09.65on Petrography.Current edition approved May 1, 2017. Published June 2017. Originallyapproved in 1975. Last previous edition approved in 2012 as C823/C823M12.DOI: 10.
15、1520/C0823_C0823M-12R17.2For referenced 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
16、 at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles
17、 for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1purposes and to serve a variety of objectives, some of whichare discussed in the Procedural Plan Section.5. Qualifications and Instruction of
18、 Personnel5.1 QualificationsThe examination, formulation of sam-pling plan, and the sampling procedures shall be performed bypersons qualified by education and experience to carry out suchwork, to operate equipment employed, to record and interpretobservations, and to report upon the sampling plan a
19、nd itsexecution. Technicians and workmen may be required to assistin the operations but appropriate training and supervision aremandatory.5.2 Instruction of PersonnelThis practice may be used bypersonnel employed directly by those for whom the examina-tion and sampling program are conducted. The emp
20、loyershould tell the personnel in as much detail as necessary, thepurposes and objectives of the examination, the kind ofinformation sought, and the extent of examination and sam-pling desired. Pertinent background information should bemade available. If the person to perform the work is highlyexper
21、ienced, the employer should seek his or her advice indelineating the investigation. The nature, extent, and objectivesof the examination and sampling plan should be recorded, andthe record may appropriately include the items under Agree-ments with Consultants.5.3 Agreements with ConsultantsThis prac
22、tice may be thebasis for establishing arrangements between a purchaser of aconsulting service and the consultant. The purchaser andconsultant should jointly determine the nature, extent, andobjectives of the examination and sampling program to bemade, and should record their agreement in writing. Th
23、eagreement may stipulate specific determinations to be made,observations to be reported, numbers and kinds of samples tobe taken, level of reliability required for results of tests,portions of the constructions to be sampled, funds to beobligated, a time schedule for the investigation, or a combina-
24、tion of these and other conditions.EXAMINATION OF CONCRETE INCONSTRUCTIONS6. Procedural Plan6.1 ObjectiveThe objective of the examination of concreteis to provide information that can be used to evaluate thecondition of the concrete and the constructions, and to cor-roborate observed satisfactory pe
25、rformance, or to documentand explain distress or failure. The examination of concrete inservice or under test should be undertaken in accordance witha scope, an objective, and systematic procedures, all agreedupon between the responsible parties. The extent of theinvestigation and the procedures tha
26、t are most appropriate forthe examination depend upon a decision as to the objectives ofthe investigation and the level of reliability required ofresulting test data. This decision may stipulate an authorizedbudget and a time schedule for completion of various stages ofthe investigation. The budget
27、and time schedule can bemodified following preliminary investigations and adjustedperiodically as information accumulates.6.2 PurposeInvestigations of the condition of concrete inservice are usually undertaken for the following reasons: (a)todetermine the ability of the concrete to perform satisfact
28、orilyunder anticipated conditions of future service; (b) to identifythe processes or materials causing distress or failure; (c)todiscover conditions in the concrete that caused or contributedto satisfactory performance or to failure; (d) to establishmethods for repair or replacement without hazard o
29、f recurrenceof the distress; (e) to determine conformance with constructionspecification requirements; (f) to develop data to aid in fixingfinancial and legal responsibility for cases involving failure orunsatisfactory service; and (g) to evaluate the performance ofthe components used in the concret
30、e. It is assumed that themanager of the investigation will begin with one or moreworking hypotheses, derived from information received orgathered, that are intended to explain the reasons for thecondition or conditions of the concrete, and that will becontinuously revised and refined as more informa
31、tion isreceived. It is intended that at the end of the investigation, anexplanation will have been produced which is the best obtain-able from the investigation of the available evidence concern-ing the mechanisms that operated to produce the condition orconditions of the constructions.6.3 Scope of
32、InvestigationThe scope of an investigation ofconcrete in service may be limited to only isolated areasdisplaying deterioration. Or the investigation may be con-cerned with general distress, such as excessive deflection orcollapse of structural members. It may involve study of thedislocation of entir
33、e structures or large portions of structures.The investigation may be confined chiefly to the study of theconcrete, or it may require substantial research into othercircumstances, such as foundation conditions, conditions ofservice, construction practices, and comparisons with otherstructures.7. Pre
34、liminary Investigations7.1 PurposeThe purpose of preliminary investigations isto establish the general condition of the concrete and theexistence of any unsatisfactory condition, to describe its nature,and to estimate its extent and possible effect upon theperformance, service life, and safety of th
35、e structure. Aninvestigation of failure or inadequate performance of concretein constructions is predicated upon a conclusion, usually by theowner or his representatives, that an unsatisfactory conditionexists or is imminent. Such a conclusion may be in error, eitherbecause the observed condition is
36、 insignificant, or because thefull extent of the actual distress or inadequacy has not beendetected.7.2 Test MethodsThe preliminary investigation mayinclude, as appropriate, visual inspection of the structure,review of plans and specifications for the work, and examina-tion of available reports of p
37、roject engineers and inspectors,compilation of available data on service conditions, petro-graphic examination in accordance with Practice C856, andtesting of a few selected samples of concrete and secondarychemical deposits in or on the concrete or both. Deflection orexpansion (or shrinkage) of typ
38、ical portions of the structureC823/C823M 12 (2017)2might appropriately be measured. The condition of the con-crete in place can be estimated using nondestructive testingprocedures, such as impact devices and ultrasonic methods (seeTest Method C597). Selected critical portions of structures maybe pro
39、bed and sampled by drilling (Method C42/C42M). Thecores may be tested in accordance with Test Method C215.Borehole cameras and viewing devices have been found to behelpful in specific instances (1, 2, 3).37.3 ConclusionsThe findings of the preliminary investiga-tion may allay all concern with respec
40、t to the condition of theconcrete. In certain cases, the findings are adequate for a finalconclusion on the significance of observed distress. Otherwise,care should be taken to assure that the preliminary investiga-tion provides the information necessary to delineate a plan forthe further investigat
41、ions covered in Sections 814.8. Assembly of Records8.1 Reports and Legal DocumentsThe investigation ofconcrete performance should be preceded or accompanied bythe assembly and critical review of records pertaining to theproject specifications, construction contract, constructionoperations, concrete-
42、making materials, weather conditions dur-ing and after construction, and the actual conditions of service.Such records should establish the specified requirements forthe materials and the completed work, and may reveal circum-stances or conditions that caused or contributed to the distressof the con
43、crete. Records of operation and maintenance maydescribe the beginning and progress of unsatisfactory perfor-mance.8.2 InterviewsInterviews with contractors, engineers,inspectors, tradesmen, and suppliers should be conducted toobtain pertinent information that is not included in the writtenrecord. Ow
44、ners, occupants, and users of the constructionsshould be queried concerning the onset and progress of evidentdistress, especially with respect to possible relationship to anychange of the conditions of use and service.9. Detailed Investigations of Concrete in Constructions9.1 ProceduresA detailed in
45、vestigation of concrete inconstructions should include all procedures that are required toachieve the approved scope and objectives within the autho-rized budget and time schedule. After the preliminary investi-gation to establish the general condition of the concrete and theextent of any unsatisfac
46、tory performance, the detailed investi-gation may comprise: (a) thorough examination of the concreteconstructions; (b) surveys and field tests to define and evaluatethe condition of the concrete in place and the safety of theconstructions; and (c) taking samples to be examined andtested by laborator
47、y procedures.9.2 Scope of Field ExaminationA detailed visual exami-nation should be made by personnel familiar with concrete andconcrete constructions. This examination should locate anddescribe all of the categories of concrete.All affected construc-tions or portions thereof should be identified an
48、d the externalaspects of failure should be described as quantitatively aspossible. The examination may be extended to aggregatesources in accordance with the procedures described in Prac-tice C295. Photographs of pertinent features of theconstructions, their environs, and the manifestations of failu
49、reare valuable and should be obtained.9.3 ObservationsFeatures of the concrete to be notedespecially include: (a) the nature and extent of cracking andfractures; (b) evidences of volume change, deflection, ordislocation of the constructions or portions thereof, which mayinclude the closing or opening of joints, tilting, shearing, ormisalignment of structural elements and shifting or misalign-ment of machinery; (c) the condition of exposed surfaces,especially such features as spalling, popouts, unusualweakness, disintegration, excessive wear, and discolorat
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