1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS 1881-210:2013Testing hardened concretePart 210: Determination of thepotential carbonation resistance ofconcrete Accelerated carbonationmethodPublishing and copyright informati
2、onThe BSI copyright notice displayed in this document indicates when the documentwas last issued. The British Standards Institution 2013Published by BSI Standards Limited 2013ISBN 978 0 580 78352 4ICS 91.100.30The following BSI references relate to the work on this standard:Committee reference B/517
3、Draft for comment 12/30260361 DCPublication historyFirst (present) edition June 2013Amendments issued since publicationDate Text affectedBS 1881-210:2013 BRITISH STANDARDContentsForeword iiIntroduction 11 Scope 12 Normative references 13 Terms and definitions 14 Principle 25 Reagents and apparatus26
4、 Production of specimens 37 Carbonation depth measurements 58 Determination of the carbonation depth 69 Test Report 710 Precision 8AnnexesAnnex A (informative) Guidance on suitable storage chambers 9Bibliography 14List of figuresFigure 1 Sealing of prism specimen prior to and during testing 5Figure
5、2 Procedure for obtaining the carbonation depth where the point fallswithin a dense aggregate particle 6Figure 3 Procedure for obtaining the carbonation depth where the point fallson a porous aggregate particle or on air void. 7Figure A.1 Typical storage chamber with vertical storage 10Figure A.2 CO
6、2monitoring/injection apparatus 11Figure A.3 CO2controller 12Figure A.4 Horizontal storage of specimens 13Summary of pagesThis document comprises a front cover, an inside front cover, pages i to iv,pages 1 to 14, an inside back cover and a back cover.BRITISH STANDARD BS 1881-210:2013 The British Sta
7、ndards Institution 2013 iForewordPublishing informationThis part of BS 1881 is published by BSI Standards Limited, under licence fromThe British Standards Institution, and came into effect on 30 June 2013. It wasprepared by Technical Committee B/517, Concrete and related products. A list oforganizat
8、ions represented on this committee can be obtained on request to itssecretary.Information about this documentThis part of BS 1881 is based on prTS12390-12, which received a negative vote.Consequently the CEN work item has been deleted. As this standard reflectedUK experience with accelerated carbona
9、tion testing, it has been published as aBritish Standard with modifications to eliminate the various options.Relationship with other publicationsBS 1881 is published in the following parts: BS 1881-113, Method for making and curing no-fines cubes; BS 1881-119, Method for determination of compressive
10、 strength usingportions of beams broken in flexure (equivalent cube method); BS 1881-122, Method for determination of water absorption; BS 1881-124, Methods for analysis of hardened concrete; BS 1881-125, Method for mixing and sampling fresh concrete in thelaboratory; BS 1881-128, Method for analysi
11、s of fresh concrete; BS 1881-129, Method for the determination of density of partiallycompacted semi-dry fresh concrete; BS 1881-130, Method for temperature matched curing of concretespecimens; BS 1881-131, Methods for testing cement in a reference concrete; BS 1881-201, Guide to the use of non-dest
12、ructive methods of test forhardened concrete; BS 1881-204, Recommendations on the use of electromagnetic covermeters; BS 1881-206, Recommendations for determination of strain in concrete; BS 1881-207, Recommendations for the assessment of concrete strength bynear-to-surface tests; BS 1881-208, Recom
13、mendations for the initial surface absorption ofconcrete; BS 1881-209, Recommendations for the measurement of dynamic modulusof elasticity of concrete; DD 216, Determination of chloride content of fresh concrete.Presentational conventionsThe provisions of this standard are presented in roman (i.e. u
14、pright) type. Itsrequirements are expressed in sentences in which the principal auxiliary verb is“shall”.Commentary, explanation and general informative material is presented insmaller italic type, and does not constitute a normative element.BRITISH STANDARDBS 1881-210:2013ii The British Standards I
15、nstitution 2013Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legalobligations.BRITISH STANDARD BS 1881-210:20
16、13 The British Standards Institution 2013 iiiBRITISH STANDARDBS 1881-210:2013This page deliberately left blankiv The British Standards Institution 2013IntroductionFerrous steel reinforced concrete structures need to be durable to ensure thatthe intended working life is achieved. The corrosion of rei
17、nforcement inducedby carbonation can play a significant role in a structures serviceability andconsequently, carbonation resistance of concrete is an important property tomeasure.1 ScopeThis part of BS 1881 describes a method for ranking the potential carbonationresistance of concrete using an accel
18、erated carbonation test.NOTE 1 This test is an accelerated test because there is exposure to much higherthan atmospheric levels of CO2and is at a relative humidity conducive to a maximumrate of carbonation.NOTE 2 The test under reference conditions takes a minimum of 112 dayscomprising a minimum age
19、 of the specimen prior to conditioning of 28 days, aminimum conditioning period of 14 days and a minimum exposure to increased CO2levels of 70 days.NOTE 3 The use of such test data in service-life modelling is still a matter of muchacademic debate and at present there is no consensus on an appropria
20、te model.It is not a method for the determination of carbonation depths in existingconcrete structures.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in thisdocument and are indispensible for its application. For dated references, onlythe edition cited
21、 applies. For undated references, the latest edition of thereferenced document (including any amendments) applies.BS EN 12350-2, Testing fresh concrete Part 2: Slump testBS EN 12350-3, Testing fresh concrete Part 3: Vebe testBS EN 12350-4, Testing fresh concrete Part 4: Degree of compactabilityBS EN
22、 12350-5, Testing fresh concrete Part 5: Flow table testBS EN 12390-1, Testing hardened concrete Part 1: Shape, dimensions and otherrequirements for specimens and mouldsBS EN 12390-2:2009, Testing hardened concrete Part 2: Making and curingspecimens for strength testsBS EN 12390-3, Testing hardened
23、concrete Part 3: Compressive strength of testspecimens3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1 depth of carbonationdepth measured using a phenolphthalein solution sprayed on the freshly-splitconcrete surfaceBRITISH STANDARD BS 1881-210:2
24、013 The British Standards Institution 2013 13.2 single point carbonation depthdepth of carbonation measured at a single point on a specimen, dk, point3.3 specimen face carbonation depthmean depth of carbonation of a single exposed face of a single specimen, dk, face3.4 specimen carbonation depthmean
25、 depth of carbonation of a single specimen, dk, spec3.5 mean carbonation depthmean depth of carbonation of two specimens, dk4 PrincipleTwo concrete cubes are cast and cured for 28 days in accordance withBS EN 12390-2. The two concrete cubes are then conditioned in a laboratory airenvironment for 14
26、days prior to sealing the top, bottom and two opposite sidefaces. After sealing of all but two faces, the cubes are placed in a storagechamber with CO2level of (4.0 0.5)%, temperature (20 2) C and relativehumidity (55 5)% for a period of at least 70 days. After 70 days exposure, thecubes are split i
27、n half perpendicular to the exposed faces, and the depth ofcarbonation is measured in accordance with this British Standard, which is takenfrom RILEM CPC-18 1, giving a single determination of the depth ofaccelerated carbonation.NOTE Experience has shown that reliance on a single determination of ac
28、celeratedcarbonation depth might (rarely) give a non-representative value 2. This risk iseliminated by testing at five weeks, seven weeks and ten weeks and inspecting theresulting curve for any unusual value.When testing at more than one age, concrete prisms are used. Two prisms arecast and cured fo
29、r 28 days in accordance with BS EN 12390-2. The prisms areconditioned in a laboratory air environment for 14 days prior to sealing the top,bottom and two end faces. After sealing all but two longitudinal faces, theprisms are placed in a storage chamber with CO2level of (4.0 0.5)%,temperature (20 2)
30、C and relative humidity (55 5)% for the overall testperiod of at least 70 days. After each exposure period, a 50 mm slice is brokenfrom each prism and tested for carbonation depth. After splitting off a slice, thesplit end faces of the prisms are sealed and the remainder of the prismsreturned to the
31、 storage chamber.Ten single point carbonation depths, dk, point,are measured after each exposureperiod on each prism or cube and the depth of carbonation, dk, is expressed asthe mean of the 20 readings.5 Reagents and apparatus5.1 Paraffin wax or equivalent, to seal the non-exposed faces of test spec
32、imens.5.2 Solution of 1g of phenolphthalein powder dissolved in a 100 ml solution of70 ml ethanol and 30 ml of deionized water.WARNING. The European Chemical Agency is proposing that phenolphthaleinis classified as a substance of very high concern on the basis of itsclassification as carcinogen cate
33、gory 1B. Handle phenolphthalein powderusing safety gloves in a fume cupboard fitted with an extractor.5.3 Magnifier and gauge, capable of measuring the depth of carbonationperpendicular to the exposed concrete surface with a precision of 0.2 mm.BRITISH STANDARDBS 1881-210:20132 The British Standards
34、 Institution 20135.4 Storage chamber, with a CO2concentration (4.0 0.5)% by volume,temperature (20 2) C and relative humidity (55 5)%.NOTE 1 See Annex A for information on a suitable chamber.NOTE 2 Experience 3 has shown that if saturated surface-dry specimens are placedin the storage chamber shortl
35、y after removal from water curing, the relativehumidity might exceed that permitted. Also, in storage chambers without activecontrol of the levels can drop below the permitted tolerance as the carbonationprocess continues. The storage chamber should therefore have active control onrelative humidity
36、and temperature.NOTE 3 Relative humidity levels may be maintained using methods at the discretionof the laboratory, for example by active humidification and/or dehumidification orsaturated salt solutions.5.5 Apparatus for recording the relative humidity, with a precision of 2.0% andthe temperature w
37、ith a precision of 0.5 C.5.6 Apparatus for recording CO2concentration, with a precision of 0.1% byvolume.NOTE Recording apparatus should be fitted with an audio or visual alarm to alertbreaches of CO2concentration within the storage chamber due to possible apparatusmalfunction.5.7 Fans, capable of f
38、acilitating steady circulation of air within the storagechamber.6 Production of specimens6.1 GeneralMake cubes and/or prisms for the determination of the carbonation resistance inaccordance with this British Standard. If the specimens are to be made by a testlaboratory, supply them with a full speci
39、fication including the mix quantities andthe mixing procedure, and where appropriate, the constituent materials. Wherethe specimens are prepared by the client or their representative, inform the testlaboratory of the day of casting and record that the specimens were stored inaccordance with this Bri
40、tish Standard.Ensure prisms are not less than 280 mm long with a cross-section of not lessthan 70 mm 70 mm from which slices approximately 50 mm thick can be splitoff at each date of carbonation testing. For a single determination ofcarbonation depth, 100 mm or greater cubes may be used. Ensure that
41、 theshortest dimension of the prism/cube is not less than 4 times the maximumnominal upper aggregate size.NOTE The use of mould release agents on the prism/cube moulds should beavoided as they can influence the carbonation depth.6.2 Making prism/cubes and making and testing prism and cubes6.2.1 For
42、each mix, cast two prisms/cubes from a single batch of concrete. Castprisms horizontally in accordance with BS EN 12390-2:2009, 5.1 to 5.4.6.2.2 After finishing the prisms/cubes, cover the exposed surface with polytheneor similar impermeable sheeting to prevent drying.6.2.3 After (20 4) h, strip the
43、 moulds and transfer the prisms/cubes withoutdelay into a water filled bath with temperature control (20 2) C in accordancewith BS EN 12390-2.BRITISH STANDARD BS 1881-210:2013 The British Standards Institution 2013 3NOTE 1 At least two compressive strength specimens should be made and tested inaccor
44、dance with BS EN 12390-2 at 28 days. Where a number of mixes are made,additional testing, e.g. the 28 day strength, should be undertaken to confirmconsistent manufacture, or identify anomalous batches where mixes might need tobe repeated.6.2.4 Upon removal of the specimens from the curing tank, imme
45、diately wrapand seal them in polythene or a similar material that can prevent drying duringtransportation or transport them whilst remaining fully immersed in water,e.g. in a mobile curing tank.6.2.5 On arrival at the test laboratory, unwrap and ensure that the testspecimens have not been damaged.6.
46、2.6 Store the test specimens in a water filled curing tank with temperaturecontrol (20 2) C in accordance with BS EN 12390-2:2009 until they are 28 daysold.6.2.7 At an age of 28 days, remove the prisms/cubes from the water bath andtransfer them to a laboratory air drying environment (between 18 C an
47、d 25 C,between 50% and 65% relative humidity) for 14 days.6.2.8 After 14 days conditioning, seal the top and bottom longitudinal faces andthe two end faces of prisms (or top, bottom and two side faces of cubes) usingparaffin wax or a similar material that can prevent ingress of CO2and allowcarbonati
48、on on two cast longitudinal surfaces, see Figure 1.NOTE 1 The purpose of sealing the top, bottom and end faces is to minimize anycorner effect from multi directional carbonation and also to prevent longitudinalcarbonation taking place through the prism/cube.NOTE 2 If paraffin wax is used to seal the
49、 surfaces, melt it in a temperaturecontrolled crucible and apply to the concrete surface with a paint brush in threeequal layers, leaving the wax to set on the concrete between each application.BRITISH STANDARDBS 1881-210:20134 The British Standards Institution 2013Figure 1 Sealing of prism specimen prior to and during testingKey1 Waxed faces 3 Concrete slice split and sprayed with phenolphthalein2 Exposed faces 4 Prism split and resealed6.2.9 Place the prisms/cubes in the carbonation st
