1、PD CEN/TR15739:2008ICS 91.100.30NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWPUBLISHED DOCUMENTPrecast concreteproducts Concrete finishes IdentificationThis Published Documentwas published under theauthority of the StandardsPolicy and StrategyCommittee on 31 August2009 BSI 2
2、009ISBN 978 0 580 60337 2Amendments/corrigenda issued since publicationDate CommentsPD CEN/TR 15739:2008National forewordThis Published Document is the UK implementation of CEN/TR15739:2008.The UK participation in its preparation was entrusted to TechnicalCommittee B/524, Precast concrete products.A
3、 list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom lega
4、l obligations.TECHNICAL REPORTRAPPORT TECHNIQUETECHNISCHER BERICHTCEN/TR 15739December 2008ICS 91.100.30English VersionPrecast concrete products - Concrete finishes - IdentificationProduits prfabriqus en bton - Surface et parements debton - lments didentificationBetonfertigteile - Betonoberflchen -B
5、eschreibungsmerkmaleThis Technical Report was approved by CEN on 23 March 2008. It has been drawn up by the Technical Committee CEN/TC 229.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary,
6、Iceland, Ireland, Italy, Latvia, Lithuania, 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
7、Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. CEN/TR 15739:2008: EPD CEN/TR 15739:2008CEN/TR 15739:2008 (E) 2 Contents Page Foreword 3Introduction .41 Scope 62 Terms and definitions 62.1 Faces .62.2 F
8、inishes .62.3 Surface characteristics .93 Principle of characterization and identification . 103.1 General . 103.2 Flatness 103.3 Texture . 103.4 Colour . 103.5 Identification of the reference 103.6 Definition of level of quality . 114 Test methods . 124.1 Flatness (deflection) . 124.2 Check of appe
9、arance 145 Description of units 16Annex A (informative) Surface characteristics 17Annex B (informative) Example of specifications of requirements applicable to architectural units 18Annex C (informative) Concrete sample surface finish example of acceptance report 19Annex D (informative) Reference im
10、ages to identify the severity of blowholes in concrete surfaces 20Annex E (informative) CIB grey scale . 22Annex F (informative) Examples of pictures deal with some methods of concrete finishes . 23Bibliography . 25PD CEN/TR 15739:2008CEN/TR 15739:2008 (E) 3 Foreword This document (CEN/TR 15739:2008
11、) has been prepared by Technical Committee CEN/TC 229 “Precast concrete products”, the secretariat of which is held by AFNOR. PD CEN/TR 15739:2008CEN/TR 15739:2008 (E) 4 Introduction The visual perception of concrete finishes is determined by characteristics which can vary to different extents, i.e.
12、 variations which are intentional (more or less). Intended variations imply that one is acquainted with the material and is able to vary the characteristic within limits set by oneself, without the variations being regarded as defects. Finishes depend on manufacturing techniques such as: Before cast
13、ing The finish is determined by the surface of the mould: smooth ex-mould finish, profiled from the mould, profiled/patterned from a lining in the mould, cast-on elements, use of retarders. Mould-hardened off-the-form finish As cast finish obtained through contact with the mould in the case of concr
14、ete hardened in the mould. The face may be smooth or textured. Dry-cast off-the-form finish As cast fair-faced finish obtained through contact with the mould in the case of immediate demoulding. The characteristics of concrete finishes are: Texture, from the most elaborated to evenness and, if it is
15、 more coarse, unevenness, possibility developing to a maximum unevenness, which is difficult to stipulate; Colour which can be expressed in colour scale; Grey tone which can be expressed in grey scales, sometimes with some colour incorporated; Pattern, a characteristic, in another type and scale tha
16、n three above, and which can be formed by variations in these characteristics. In contrast to the consciously selected characteristics there can be additional surface aspects of sorts which are not desired which consequently should be named deviations (i.e. deviations from intentional characteristic
17、s or from the quality level for these characteristics). To these belongs blowholes, lumps, groove etc. As a consequence one should separate between characteristics on one side and deviations on the other side and consider them as different matters, due to the great difference in their nature. PD CEN
18、/TR 15739:2008CEN/TR 15739:2008 (E) 5 In contrast one should observe that blowholes in certain cases can be intentional, if they are uniformly distributed over a concrete surface, to lend it a visual “softness”. For some products, such as architectural components, the required surface appearance cou
19、ld be chosen on the basis of samples for coordinating the surface character. Before building and delivery, start reference surfaces are chosen from the sample surface. At the time an order is placed, agreement on the appearance of the face(s) is formalized by an acceptance report for the reference s
20、ample(s) proposed by the manufacturer. This report also identifies the conventional mean colour chosen from a reference colour chart to be used to subsequently assess consistency of colour (see Annex C and Annex E). NOTE 1 Colour scales are not included in this CEN technical report because the paper
21、 publication is in black and white. Each country could establish special colour scales. NOTE 2 The consistency of concrete appearance is governed by the uniformity of the raw materials from which it is made or of the pigments used. The fact that the raw materials are of natural mineral origin implie
22、s tolerances on the appearance of the concrete products supplied. NOTE 3 Because of the time it takes for concrete to cure, the appearance of the reference sample can be assessed only after a certain minimum time, generally one week after treatment, or longer, depending on the cements used (e.g. CEM
23、 II A and CEM II B) and in all cases at delivery. NOTE 4 When the colour consistency of several products is inspected at the same time, account should be taken of any age differences. PD CEN/TR 15739:2008CEN/TR 15739:2008 (E) 6 1 Scope This document provides guidelines for the surface appearance of
24、precast concrete products and the methods for inspecting and assessing the conformity of appearance for use in conjunction with specific product standards. This document may also be used to describe the appearance of products for which there is no standard. If there is a specific standard for a prec
25、ast concrete product, it takes priority over this document. 2 Terms and definitions For the purposes of this document, the following terms and definitions apply. 2.1 Faces 2.1.1 seen face surface intended to be seen when in use 2.1.2 facing layer layer of concrete on the seen face of a product of di
26、fferent material and/or properties to the main body or backing layer of a product. Facing layer may be not completely mixed colour concrete (marbling) NOTE To be distinguished from wipe, i.e. a fine cement mortar or slurry applied to the surface of the product. 2.1.3 arris part of a product where tw
27、o faces meet. It can be bevelled, rounded, chamfered, radiussed or splayed 2.1.4 draw intended angle of the side face from the vertical plane of a product 2.1.5 chamfer bevelled arris 2.2 Finishes 2.2.1 General 2.2.1.1 unformed surface surface not in contact with the mould during moulding. This surf
28、ace may be given complementary treatment while the concrete is still green to give a more uniform finish. The different treatments possible are defined below NOTE In certain special cases the shape of the precast unit may require application of a moulding surface to the upper face of the unit; this
29、may result in a large number of blowholes which may be attenuated by one of the surface treatments defined below. 2.2.1.2 screeded finish obtained by drawing a straightedge, for example, across the surface of the concrete PD CEN/TR 15739:2008CEN/TR 15739:2008 (E) 7 2.2.1.3 rubbed-off finish obtained
30、 by using a rubbing board , for example, or similar tool NOTE Cement and sand may be sprinkled on and worked into bleeding concrete or mortar if the quantities are moderate and the work is regular and carried out with an equally proportioned mix of cement and very fine sand. Use of cement alone is p
31、rohibited. 2.2.1.4 trowelled finish obtained by using a steel or other kind of trowel, for example 2.2.1.5 semi-polished finish obtained when the surface of the concrete is semi-polished with a rag or expanded polystyrene, for example, or brushed with a soft or other kind of brush 2.2.1.6 imprinted
32、finish obtained by using an indent roller or similar tool to be defined at the time of the order 2.2.2 Worked surfaces 2.2.2.1 Worked in plastic state 2.2.2.1.1 brushed roughness created by brushing the surface of the fresh mortar with a stiff brush 2.2.2.1.2 water-washed surface from which the firs
33、t 2 mm and more of fine mortar is removed by washing 2.2.2.1.3 fine washed surface from which not more than 2 mm of the first fine mortar is removed by washing 2.2.2.2 Worked in hardened state 2.2.2.2.1 bush hammered result of scalling the surface of hardened concrete with a bush hammer 2.2.2.2.2 ac
34、id-etched exposed aggregate finish in which the aggregate has been exposed by putting an acid solution on the surface for a time and washing it off with water 2.2.2.2.3 chemically retarded exposed aggregate finish (to a greater or lesser extent) in which the concrete surface has been treated with a
35、retarder and the hardened product has been washed down with water and/or brushed 2.2.2.2.4 splitted irregularly chipped or hammered face revealing all the constituents of the concrete, including broken coarse aggregate PD CEN/TR 15739:2008CEN/TR 15739:2008 (E) 8 NOTE The above techniques require con
36、siderable skill in the work procedures, and require extra concrete cover in the case of reinforced products. 2.2.2.2.5 flamed exposed aggregate finish in which the top few millimetres of the surface have been flaked off by flame action, for example 2.2.2.2.6 finely ground surface ground back with a
37、mechanical grinder, used wet or dry, to partially expose the fine aggregate (sand) 2.2.2.2.7 grinded description of a surface which is grinded once without abrading. Brush marks and pores can be visible 2.2.2.2.8 coarsely ground surface ground back to some depth with a mechanical grinder, used wet o
38、r dry, to reveal the deep texture of the concrete and provide rough surface retaining grinding marks 2.2.2.2.9 polished coarsely ground surface ground several times with increasingly fine grit heads to achieve a uniform finish without visible marks. Depending on the type of aggregate and the final t
39、reatment, the finish may be gloss, with or without blowholes 2.2.2.2.10 sawed raspy surface without any more preparation 2.2.2.2.11 abrasive blasted hardened concrete surface blasted with sand or grit. The grading of the grit, its hardness, and the spray pressure used enable variation from brush bla
40、sting (light abrasion of the surface skin) to heavy blasting that partially exposes the aggregate 2.2.2.2.12 pressure jetted hardened concrete surface sprayed with a high-pressure water jet NOTE The water pressure and adjustment of the jet enable the depth of abrasion and therefore the resulting fin
41、ish to be varied. 2.2.2.2.13 shot blasting erosion of surface by projection of steel shot 2.2.2.2.14 aging processing with special hammering techniques will give a rustic and antique look 2.2.2.2.15 bossed on the split surface, aris are broken to give an effect of cut stones 2.2.2.2.16 point tooling
42、 result of scalling the surface of hardened concrete with a pointed graver PD CEN/TR 15739:2008CEN/TR 15739:2008 (E) 9 2.2.3 Painted or coated surface 2.2.3.1 coated surface surface faced at delivery in accordance with stipulations made at the time of the order 2.2.3.2 surface to be painted or coate
43、d surface to be painted or coated after delivery NOTE 1 Since the requisite finish depends on the type and “build“ of the paint to be used, these parameters should be known at the time of the order. NOTE 2 Any mould release agent on the surface should be compatible with the stipulated paint or coati
44、ng. 2.3 Surface characteristics Surface characteristics are defined in Table 1 and Annex A. Table 1 Surface characteristics Characteristics Description Blowholes In mass concrete: voids at the surface of the concrete. For facing concrete: defects consisting of the appearance of bubbles (blisters) or
45、 pits (burst bubbles), generally around 5 mm deep and between a few millimetres and a few centimetres in diameter (cf. Annex D). Large crack Crack more than 2 mm wide. Scaling Thin layer of hardened mortar separating from the concrete surface in fragments called flakes. Corner spalling Spalling at t
46、he corner of the concrete unit. Efflorescence Fine, generally whitish crystalline deposit forming at the concrete surface. NOTE When efflorescence occurs it is not deleterious to the performance of the product in use and is not considered significant. Spalling Detachment of fragments from a concrete
47、 surface. Crazing Network of fine and shallow cracks forming a regular mesh. Appears at the surface of the concrete. Crack More or less regular linear opening (discontinuity) in the concrete, between 0,2 mm and 2 mm wide. Any smaller or larger, and it is a micro crack or a large crack. Surface crack
48、 Crack that does not go through the thickness of the structure. It is widest at the surface and becomes zero at depth. Laitence Laitence is a mixture of water and the finer constituents of the concrete. Swelling Swollen appearance of the concrete due to an increase in volume. Micro crack Very tight,
49、 more or less regular, most commonly discontinuous linear crack less than 0,2 mm wide. May extend to form a network. Honeycombing Defect with lack of fines or mortar between aggregates. “aggregate transparency” Marbling effect Large aggregate appearance through the concrete surface, creating a network of oval marks which may be darker or lighter than the rest of the surface, depending on the case. Surface wear Wear of the concrete due to abrasion or erosion. Colour variatio
