CEN TS 14754-1-2007 Curing compounds - Test methods - Part 1 Determination of water retention efficiency of common curing compounds《养护剂的试验方法 第1部分 普通养护剂保水率的测定》.pdf

1、DRAFT FOR DEVELOPMENTDD CEN/TS 14754-1:2007Curing compounds Test methods Part 1: Determination of water retention efficiency of common curing compoundsICS 91.100.30g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g4

2、8g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58DD CEN/TS 14754-1:2007This Draft for Development was published under the authority of the Standards Policy and Strategy Committee on 31 August 2007 BSI 2007ISBN 978 0 580 54051 6National forewordThis Draft for Development is the UK impl

3、ementation of CEN/TS 14754-1:2007. This publication is not to be regarded as a British Standard.It is being issued in the Draft for Development series of publications and is of a provisional nature. It should be applied on this provisional basis, so that information and experience of its practical a

4、pplication can be obtained.Comments arising from the use of this Draft for Development are requested so that UK experience can be reported to the European organization responsible for its conversion to a European standard. A review of this publication will be initiated not later than 3 years after i

5、ts publication by the European organization so that a decision can be taken on its status. Notification of the start of the review period will be made in an announcement in the appropriate issue of Update Standards.According to the replies received by the end of the review period, the responsible BS

6、I Committee will decide whether to support the conversion into a European Standard, to extend the life of the Technical Specification or to withdraw it. Comments should be sent to the Secretary of the responsible BSI Technical Committee at British Standards House, 389 Chiswick High Road, London W4 4

7、AL.The UK participation in its preparation was entrusted by Technical Committee B/517, Concrete, to Subcommittee B/517/3, Admixtures.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provis

8、ions of a contract. Users are responsible for its correct application.Amendments issued since publicationAmd. No. Date CommentsTECHNICAL SPECIFICATIONSPCIFICATION TECHNIQUETECHNISCHE SPEZIFIKATIONCEN/TS 14754-1March 2007ICS 91.100.30English VersionCuring compounds - Test methods - Part 1: Determinat

9、ion ofwater retention efficiency of common curing compoundsProduits de cure - Mthodes dessai - Partie 1 :Dtermination de lefficacit de protection des produits decure courantsNachbehandlungsmittel - Prfverfahren - Teil 1:Bestimmung der Wasserrckhaltefhigkeit von blichenNachbehandlungsmittelnThis Tech

10、nical Specification (CEN/TS) was approved by CEN on 3 July 2006 for provisional application.The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit theircomments, particularly on the question whether the CEN/TS can be

11、converted into a European Standard.CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS availablepromptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the C

12、EN/TS)until the final decision about the possible conversion of the CEN/TS into an EN is reached.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania

13、, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All

14、rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. CEN/TS 14754-1:2007: E2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Principle4 5 Apparatus .5 6 Reference concrete5 6.1 Constituent materials 5 6.2 Test

15、 concrete6 6.3 Production of reference concrete 6 7 Water retention efficiency test .6 7.1 Number of specimens .6 7.2 Determination of loss of solvent7 7.3 Procedure .7 8 Calculations8 9 Test report 9 CEN/TS 14754-1:20073 Foreword This document (CEN/TS 14754-1:2007) has been prepared by Technical Co

16、mmittee CEN/TC 104 “Concrete and related products”, the secretariat of which is held by DIN. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent r

17、ights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Irel

18、and, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. CEN/TS 14754-1:20074 1 Scope This Technical Specification describes a procedure for determining the ability of a curing compound to

19、 prevent the evaporation of water from young concrete when applied immediately after the bleed water has evaporated. NOTE The procedure involves application to a horizontal surface; it may not be applicable for use on vertical or sloping surfaces. 2 Normative references The following referenced docu

20、ments are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 197-1, Cement Part 1: Composition, specifications and conformity criteria f

21、or common cements. EN 206-1, Concrete Part 1: Specification, performance, production and conformity. EN 480-1, Admixtures for concrete, mortar and grout Test methods Part 1: Reference concrete and reference mortar for testing. EN 1008, Mixing water for concrete - Specification for sampling, testing

22、and assessing the suitability of water, including water recovered from processes in the concrete industry, as mixing water for concrete. EN 12350-2, Testing fresh concrete - Part 2: Slump test. EN 12350-6, Testing fresh concrete Part 6: Density. EN 12350-7, Testing fresh concrete Part 7: Air content

23、 Pressure methods. EN 12620, Aggregates for concrete. 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 curing compound liquid applied to the surface of concrete which prevents the evaporation of water after casting and/or during the hardening

24、phase at early days 3.2 water retention efficiency index the reduction in evaporation of water from the test specimen treated with a curing compound compared to an untreated specimen expressed as a percentage of the evaporation from the untreated specimen 4 Principle The test consists of: measuring

25、the quantity of water which evaporates, under specified conditions, from test specimens of concrete with and without the application of a curing compound, CEN/TS 14754-1:20075 calculating the curing efficiency index. 5 Apparatus a) non-absorbent watertight moulds of (50 000 5 000) mm2 surface area a

26、nd inside depth of (50 2) mm for the preparation of specimens made of concrete; b) vibrating table with a frequency of about 50 Hz and an amplitude of about 0.5 mm; c) scoop; d) steel float; e) non absorbent plates (e.g. glass, metal) of the same surface area as in a); f) Spray gun with a max. nozzl

27、e of 2 mm and a pressure of 1.0 MPa; g) balance of sufficient capacity to weigh the test specimens with an accuracy of 0.1 g; h) mask to ensure only the specified surface is treated; i) controlled room at (35 2) C and (40 3) % relative humidity with no air circulation on the top of the specimens or

28、ventilated room at (40 2) C NOTE Special arrangement to protect the specimens from air circulation is recommended. 6 Reference concrete 6.1 Constituent materials 6.1.1 Cement For the reference concrete use a CEM I - R cement conforming to EN 197-1. 6.1.2 Aggregate A natural normal weight aggregate c

29、onforming to EN 12620 with a water absorption 2 % by mass. Maximum nominal upper aggregate size 8 mm as defined in EN 206-1. 6.1.3 Additions To fulfil the requirements on bleeding or mat dry surface, additions according to the definitions in EN 206-1 may be used. 6.1.4 Mixing water Water conforming

30、to EN 1008. CEN/TS 14754-1:20076 6.2 Test concrete 6.2.1 Mix design Tests on reference concrete are performed as comparative tests. That is, the performance of curing agents is determined by comparing the treated concrete specimens with the untreated concrete specimens. All concrete specimens have t

31、he same mix design and constituent materials from the same delivery. Mix design by mass Cement: 1,0 Aggregates and additions: 3,0 Water: 0,42 6.2.2 Concrete properties The concrete shall be as dry as possible (slump class S1 when measured in accordance with EN 12350-2) but compactable and able to be

32、 finished to a perfectly closed and smooth surface. When tested in accordance with the procedure described in clause 6.3.2 and 7.3 there shall be no bleeding after compaction and the surface shall be mat dry within the time given in clause 7.3. The air content of the fresh concrete shall not exceed

33、3 % by volume when measured in accordance with EN 12350-7. 6.3 Production of reference concrete 6.3.1 Mix preparation Mix design shall be in accordance with clause 6.2. Aggregate is used in the oven dry condition to remove doubts on the moisture content variation. If the aggregate is not oven dry, t

34、he moisture content shall be determined and the specific gravity corrected accordingly. In case of dispute, oven dry aggregate shall be used. 6.3.2 Mixing procedure Prior to mixing, each of the constituents is conditioned to a temperature of (20 2) C. Mix the concrete in accordance with EN 480-1, ex

35、cept for the requirement for consistence, to ensure repeatability of results and eliminate the effect of initial absorption on consistence. Measure the air content in accordance with EN 12350-7 and the fresh concrete density in accordance with EN 12350-6 and make specimens after completion of mixing

36、. 7 Water retention efficiency test 7.1 Number of specimens For the test 3, concrete specimens are treated with curing compound, 3 concrete specimens are left untreated and 3 non-absorbent plates are treated with curing compound. CEN/TS 14754-1:20077 7.2 Determination of loss of solvent To determine

37、 the loss of solvent from the curing compound: Weigh the non-absorbent plate. Spray apply the curing compound at the manufacturers recommended rate. Immediately, reweigh the plate. Place the plate in the controlled room (5i) and reweigh at 6 h, 24 h and 72 h (+ 15 min). A total of 3 tests on differe

38、nt plates are carried out. Determine the coverage rate of the curing compound in g/m and the cumulative loss of solvent at each time interval. Individual and mean values are reported. 7.3 Procedure Fill the moulds with concrete in one layer and compact on the vibrating table for a maximum of 20 seco

39、nds. After compaction, finish the surface with a steel float, making the minimum number of passes and working along the length of the mould in both directions, to produce a uniform, flat, smooth and closed surface, free from undulations and surface defects. After the second water addition to the mix

40、, complete the compaction and finishing of the specimens within 45 minutes and record the time taken. After finishing the surface, store the specimens in the controlled room until the surface loses its wet sheen and record the time taken. If the time exceeds 30 min repeat the specimen preparation us

41、ing a revised test mix. As soon as the surface has lost its sheen, remove all 6 specimens from the controlled room. Weigh one specimen, cover with the mask, uniformly spray apply the curing membrane and check by intermediate weighing to obtain the manufacturers recommended rate of application. Rewei

42、gh the specimen to determine the applied weight of curing compound and the initial weight at tofor water loss determinations. Take a second specimen, leave untreated and weigh it to determine the initial weight at tofor water loss determinations. Return these two specimens to the controlled room and

43、 record the zero water loss time for this pair. Repeat this procedure for the remaining 4 specimens. Working in pairs, one test and one control specimen. All three pairs should be returned to the controlled room within 30 minutes. NOTE It can be an advantage to seal the seam between concrete and mou

44、ld with a strip of elastic material. Determine the difference of the weight before sealing and after sealing of protected and unprotected specimens to correct the weight. Keep the specimens, treated and untreated, in the controlled room for 72 h. In addition to determining the initial weight, reweig

45、h the specimens after 6 h, 24 h and 72 h. CEN/TS 14754-1:20078 8 Calculations The water retention efficiency is expressed by the curing efficiency index It. Calculate the curing efficiency index of the curing compound at the time t as a percentage from the equation: 100=RtCtRttMMMI (1) where: Itis t

46、he curing efficiency index at time “t” t is the time at which the weight of the specimens is determined (t = 0 h, 6 h, 24 h and 72 h) MRtis the average of mass loss from the untreated specimens at time “t” (specimens without curing compound) MCtis the average of mass loss from the treated specimens

47、at time “t”, reduced with the average of mass loss of the curing compound (solvent loss) at time “t” ()331Rit0RiR=itmmM (2) ()()3313100=iimmmmMSitSiCitCiCt(3) Where m is the mass of specimens according to the following table: Table 1 Mass of specimens Measurements at time t = 6 h, 24 h and/or 72 h S

48、pecimens: Specimen 1 Specimen 2 Specimen 3 Curing compound (Solvent loss) mS10mS1tmS20mS2tmS30mS3tUntreated specimens mR10mR1tmR20mR2tmR30mR3tTreated specimens mC10mC1tmC20mC2tmC30mC3tCEN/TS 14754-1:20079 9 Test report The test report shall include the following information about the test results an

49、d about the test concrete: source, notation and class of cement in accordance with EN 197-1; source, type and grading of aggregate; type and source of additions (if any); consistence of concrete; fresh bulk density; air content of fresh concrete; name or code of curing compound tested (with information relating to its marking); individual test results relating to Table 1; mean curing efficiency index at 6 h, 24 h and 72 h; time of application of curing compound expressed in minutes after second additio