1、Designation: C 823/C 823M 07Standard Practice forExamination and Sampling of HardenedConcrete in Constructions1This standard is issued under the fixed designation C 823/C 823M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the ye
2、ar of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This practice outlines proced
3、ures for visual examinationand sampling of hardened concrete in constructions. Referenceis made to the examination and sampling of concrete inprefabricated building units, precast products, and laboratoryspecimens.1.2 The values stated in either inch-pound units or SI unitsshall be regarded separate
4、ly as standard. Inch-pound units areshown in parentheses. The values stated in each system maynot be exact equivalents; therefore, each system must be usedindependently of the other. Combining values from the twosystems may result in nonconformance with the standard.1.3 This standard does not purpor
5、t 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 prior to use.2. Referenced Documents2.1 ASTM Standards:2C 42/
6、C 42M Test Method for Obtaining and Testing DrilledCores and Sawed Beams of ConcreteC 125 Terminology Relating to Concrete and ConcreteAggregatesC 215 Test Method for Fundamental Transverse, Longitu-dinal, and Torsional Resonant Frequencies of ConcreteSpecimensC 295 Guide for Petrographic Examinatio
7、n of Aggregatesfor ConcreteC 457 Test Method for Microscopical Determination ofParameters of the Air-Void System in Hardened ConcreteC 597 Test Method for Pulse Velocity Through ConcreteC 670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC 856 Practic
8、e for Petrographic Examination of HardenedConcreteE 105 Practice for Probability Sampling Of MaterialsE 122 Practice for Calculating Sample Size to Estimate,With a Specified Tolerable Error, the Average for aCharacteristic of a Lot or ProcessE 141 Practice for Acceptance of Evidence Based on theResu
9、lts of Probability Sampling3. Terminology3.1 DefinitionsFor definitions of terms used in this prac-tice, refer to Terminology C 125.3.2 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
10、 category of concrete, na specified level of quality inconcrete that is observed to be in a definable range 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 qu
11、ality butin observably different condition at the time of examination. Itis also used to refer to concrete 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 sam
12、pling can provide materials for petrographicexamination, in accordance with Practice C 856, chemical orphysical analytical procedures, or any of a wide variety of1This practice is under the jurisdiction of ASTM Committee C09 on Concreteand Concrete Aggregates , and is the direct responsibility of Su
13、bcommittee C09.65on Petrography.Current edition approved July 15, 2007. Published August 2007. Originallyapproved in 1975. Last previous edition approved in 2000 as C 823 00.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For
14、Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.destru
15、ctive 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 ofpurposes and to serve a variety of objectives, some of whichare discussed in th
16、e Procedural Plan Section.5. Qualifications and Instruction of 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
17、 interpretobservations, and to report upon the sampling plan and 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 who
18、m the examina-tion and sampling program are conducted. The employershould 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 bema
19、de available. If the person to perform the work is highlyexperienced, 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-m
20、ents with Consultants.5.3 Agreements with ConsultantsThis practice 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 progr
21、am to bemade, and should record their agreement in writing. Theagreement 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 beo
22、bligated, a time schedule for the investigation, or a combina-tion of these and other conditions.EXAMINATION OF CONCRETE INCONSTRUCTIONS6. Procedural Plan6.1 ObjectiveThe objective of the examination of con-crete is to provide information that can be used to evaluate thecondition of the concrete and
23、 the constructions, and to cor-roborate observed satisfactory performance, 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 responsibl
24、e parties. The extent of theinvestigation and the procedures that 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 f
25、or completion of various stages ofthe investigation. The budget 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:
26、 (a)todetermine the ability of the concrete to perform satisfactorilyunder 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
27、) to establishmethods for repair or replacement without hazard of 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)
28、to evaluate the performance ofthe components used in the concrete. 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,
29、and that will becontinuously revised and refined as more information 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 produ
30、ce the condition orconditions of the constructions.6.3 Scope of InvestigationThe scope of an investigationof concrete 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 str
31、uctural members. It may involve study of thedislocation of entire 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, con
32、struction practices, and comparisons with otherstructures.7. Preliminary 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 pos
33、sible effect upon the perfor-mance, service life, and safety of the structure. An investiga-tion of failure or inadequate performance of concrete inconstructions is predicated upon a conclusion, usually by theowner or his representatives, that an unsatisfactory conditionexists or is imminent. Such a
34、 conclusion may be in error, eitherbecause the observed condition is insignificant, or because thefull extent of the actual distress or inadequacy has not beendetected.7.2 Test MethodsThe preliminary investigation may in-clude, as appropriate, visual inspection of the structure, reviewof plans and s
35、pecifications for the work, and examination ofavailable reports of project engineers and inspectors, compila-tion of available data on service conditions, petrographicexamination in accordance with Practice C 856, and testing ofa few selected samples of concrete and secondary chemicaldeposits in or
36、on the concrete or both. Deflection or expansionC 823/C 823M 072(or shrinkage) of typical portions of the structure mightappropriately be measured. The condition of the concrete inplace can be estimated using nondestructive testing procedures,such as impact devices and ultrasonic methods (see TestMe
37、thod C 597). Selected critical portions of structures may beprobed and sampled by drilling (Method C 42/C 42M). Thecores may be tested in accordance with Test Method C 215.Borehole cameras and viewing devices have been found to behelpful in specific instances (1, 2, 3).37.3 ConclusionsThe findings o
38、f the preliminary investi-gation may allay all concern with respect 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 i
39、nformation necessary to delineate a plan forthe further investigations covered in Sections 8-14.8. 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 speci
40、fications, construction contract, construction op-erations, concrete-making materials, weather conditions duringand 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
41、 or conditions that caused or contributed to the distressof the concrete. Records of operation and maintenance maydescribe the beginning and progress of unsatisfactory perfor-mance.8.2 InterviewsInterviews with contractors, engineers, in-spectors, tradesmen, and suppliers should be conducted toobtai
42、n pertinent information that is not included in the writtenrecord. Owners, 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 I
43、nvestigations of Concrete in Constructions9.1 ProceduresA detailed investigation 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
44、the general condition of the concrete and theextent of any unsatisfactory 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 theconstr
45、uctions; and (c) taking samples to be examined andtested by laboratory 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.Al
46、l affected construc-tions or portions thereof should be identified and 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 C 295. Photographs of pertinent feature
47、s of the construc-tions, their environs, and the manifestations of failure arevaluable 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 c
48、onstructions 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, unusual weak-ness, disintegra
49、tion, excessive wear, and discoloration; (d)evidences of cement-aggregate reactions; (e) secondary depos-its on surfaces, in cracks, and in voids; and (f) the presence andextent of repair work and the quality of its bond to the originalconcrete.9.3.1 Some of the features listed in this section can bedetected more readily in laboratory examination.9.3.2 Some of the other properties of the concrete requiringobservation include: the thoroughness of consolidation;whether the concrete is air-entrained; evidences of segregationand bleeding; indications of extremely high, l
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