1、BRITISH STANDARD BS EN 12272-2:2003 Surface dressing Test methods Part 2: Visual assessment of defects The European Standard EN 12272-2:2003 has the status of a British Standard ICS 93.080.20 BS EN 12272-2:2003 This British Standard, was published under the authority of the Standards Policy and Stra
2、tegy Committee on 6 February 2004 BSI 6 February 2004 ISBN 0 580 42677 7 National foreword This British Standard is the official English language version of EN 12272-2:2003. The UK participation in its preparation was entrusted by Technical Committee B/510, Road materials, to Subcommittee B/510/2, S
3、urface dressings, sprays and slurry, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may b
4、e found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are
5、 responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and
6、keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 15 and a back cover. The BSI copyright notice displayed in this document
7、 indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN122722 June2003 ICS93.080.20 Englishversion SurfacedressingTestmethodsPart2:Visualassessmentof defects EnduitssuperficielsdusureMthodesdessaiPartie
8、2: Evaluationvisuelledesdfauts OberflchenbehandlungPrfverfahrenTeil2:Visuelle BeurteilungvonInhomogenitten ThisEuropeanStandardwasapprovedbyCENon21February2003. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanation
9、alstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresp
10、onsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Sl
11、ovakia,Spain,Sweden,SwitzerlandandUn ited Kingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2003CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN122722:
12、2003EEN 12272-2:2003 (E) 2 Contents Page Foreword3 1 Scope4 2 Normative references4 3 Terms and definitions .4 4 Visual assessment of defects.8 4.1 General8 4.2 Qualitative assessment.8 4.2.1 Procedure.8 4.3 Quantitative assessment9 4.3.1 Fatting up, tracking, bleeding, scabbing, and tearing .9 4.3.
13、2 Fretting10 4.3.3 Streaking.11 5 Expression of results11 5.1 General11 5.2 Qualitative assessment.11 5.3 Quantitative assessment11 5.3.1 Fatting up, tracking and bleeding 11 5.3.2 Scabbing and tearing 12 5.3.3 Fretting12 5.3.4 Streaking.12 6 Test report12 Annex A (normative) Qualitative assessment1
14、3 Annex B (normative) Quantitative assessment .14 Bibliography 15 EN 12272-2:2003 (E) 3 Foreword This document (EN 12272-2:2003) has been prepared by Technical Committee CEN/TC 227 “Road materials“, the secretariat of which is held by DIN. This European Standard shall be given the status of a nation
15、al standard, either by publication of an identical text or by endorsement, at the latest by December 2003, and conflicting national standards shall be withdrawn at the latest by December 2005. This European Standard is one of a series of standards as listed below: EN 12272-1, Surface dressing Test m
16、ethods Part 1: Rate of spread and accuracy of spread of binder and chippings EN 12272-2, Surface dressing Test methods Part 2: Visual assessment of defects EN 12272-3, Surface dressing Test method Part 3: Determination of binder aggregate adhesivity by the Vialit plate shock test method Annexes A an
17、d B are normative. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembou
18、rg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. EN 12272-2:2003 (E) 4 1 Scope This European Standard is applicable to all surface dressings (roads, airfields and other trafficked areas) and specifies qualitative and quantitative methods of the v
19、isual assessment of defects of surface dressing. The results of the qualitative evaluation carried out by visual assessment when specified shall be reported in annex A. This is a rapid practical test and may be specified as the primary test so that if the results are obvious or are without any doubt
20、 the more time consuming quantitative test method may be avoided. The quantitative test method shall be carried out when specified and the table of results in annex B reported. The visual assessment reports for both methods have identical records and thus both may be used to check the specification
21、for visual assessment of defects (prEN 12271-4). The rapid qualitative test methods is dependent on the skill and experience of the operator and therefore the repeatability and the reproducibility values will not be as precise, but the convenience of the method and lack of disruption to traffic will
22、 ensure its use. The national application document may state whether either or both or sequentially the qualitative and quantitative tests are to be used and may relate this to types of site (for example lightly trafficked roads may not be required to be quantitatively assessed). The test may be use
23、d to evaluate the durability or performance of a surface dressing. For example fretting may indicate poor adhesion of the binder to chippings. 2 Normative references Not applicable. 3 Terms and definitions For the purposes of this European Standard, the following terms and definitions apply. 3.1 mos
24、aic arrangement of chippings such that they are in shoulder to shoulder contact and are thus supported laterally NOTE The initial stability of a surface dressing is dependent upon the formation of a close mosaic and the cohesion and adhesion of the binder. Subsequent durability is gained by re-orien
25、tation of the chippings by traffic to form a tight mosaic, and sufficient binder to secure the chippings to the existing road surface before the onset of embedment. 3.2 embedment process whereby chippings are forced into an existing road surface by the action of traffic (see Figure 1) resulting in a
26、 reduction of macrotexture with time, which is rapid in the first summer and thereafter stabilises for well designed surface dressings NOTE Factors affecting embedment are increased traffic, especially heavy goods vehicles, increases the rate of embedment; road hardness: cement concrete, for example
27、, does not allow embedment; summer months, when the average road temperature is higher, results in softer roads with less resistance to embedment; size of chippings: large chippings reduce the rate of embedment; EN 12272-2:2003 (E) 5 traffic speed: slow traffic experienced on hills and at junctions
28、increases embedment by extending the loading time. Conversely, fast traffic, such as that in the overtaking lane of a dual carriageway, results in less embedment; shaded areas: a reduction in average road temperature reduces embedment; EN 12272-2:2003 (E) 6 Figure 1a No embedment (very hard substrat
29、e and/or low traffic volume) Figure 1b Typical embedment Figure 1c Fatting up (nearly total embedment soft substrate chipping size too small poor design) Key 1 Road surface level before treatment 2 Blackened surface (especially in wheel tracks) and loss of texture 3 Chippings embedded by traffic Fig
30、ure 1 - Embedment Key 1 Road surface level before treatment 2 Typical bituminous globules at the surface 3 Binder flow Figure 2 Bleeding 3.3 defect state of a surface dressing where the mosaic is covered by binder as in the case of fatting up, tracking and bleeding or is disrupted as in the case of
31、scabbing, tearing, fretting or streaking (see 3.4 to 3.10) NOTE Defects also occur due to poor methods of construction such as inadequate traffic control. Surface dressings are vulnerable to traffic stress in their early life before the binder has sufficient cohesion or emulsion binders have had a c
32、hance to break. Turning of the chippings by warm rubber tyres on exposed binder leads to disruption of the mosaic, scabbing and tearing often with an appearance similar to tracking. Missed areas and ridges caused by overlaps and other installation faults such as poor traffic management should in any
33、 case be picked up by the contractors factory production control document. EN 12272-2:2003 (E) 7 3.4 fatting up result of almost total embedment (see Figure 1a, b, c) NOTE The result of fatting up is an undesirable smooth surface (loss of macrotexture) often with excess binder at the surface leading
34、 to a very low skid resistance. Fatting up in the wheel tracks is known as tracking and is caused by channelised traffic. 3.5 tracking fatting up in the wheel tracks caused by channelised traffic, sometimes initiated by bleeding or poor construction techniques 3.6 bleeding exudation of bituminous bi
35、nder from a road surface (see Figure 2) NOTE 1 The binder rises to the surface through the mosaic of chippings. This is especially noticeable with low viscosity fluxed bituminous binders. NOTE 2 Bleeding is more likely to occur with binder rich substrates. NOTE 3 High road temperatures, low viscosit
36、y binder, excess binder, and water pressure causing stripping of the binder from underlying materials are the common causes of bleeding. NOTE 4 The result of bleeding is an undesirable smooth surface (loss of macrotexture) often with excess binder at the surface leading to a very low skid resistance
37、. The effect is similar to fatting up although not restricted to the wheel tracks and the causes are different. 3.7 scabbing detachment of both binder and chippings after application from the existing road surface NOTE 1 Scabbing often occurs when the surface of the existing road is contaminated wit
38、h mud, oil, dust, animal droppings, etc. NOTE 2 Scabbing also occurs when the existing road surface is too wet for successful adhesion of the binder. NOTE 3 Scabbing may occur when adhesion of the dressing to the existing road is less than the cohesion of the binder in the mosaic. This is noticeable
39、 on roads where bleeding has taken place and traffic has torn away areas of binder and chippings at points of high traffic stress. 3.8 tearing concentrated (localised) loss of chippings from the mosaic of a completed surface dressing or excessive fretting over a continuous area of more than 0,01 m 2
40、NOTE 1 Excessive fretting on badly constructed asphalt patch-repairs or areas under trees, is a common problem that may be corrected by careful design. NOTE 2 Tearing may occur at points of high traffic stress. NOTE 3 Tearing may occur as a result of snow or ice removal. 3.9 fretting random loss of
41、chippings from the mosaic of a completed surface dressing. Concentrated loss of chippings over a continuous area of more than 0,01 m 2is not random loss and is considered as tearing NOTE 1 Fretting occurs mainly where there is insufficient binder to hold the chippings. It is particularly noticeable
42、when the existing road surface varies in macrotexture, porosity or road hardness. EN 12272-2:2003 (E) 8 NOTE 2 When surface dressing does not stabilise to form a mosaic of chippings, fretting will generally occur when the first frosts arrive. The binder alone has insufficient cohesion to prevent the
43、 chippings from being dislodged by traffic forces. This type of brittle failure is exacerbated by short loading time due to high traffic speed and low ambient temperatures. NOTE 3 Fretting also occurs when adhesion of binder to chippings is lost. When water displaces the binder from aggregate or whe
44、n fines or dust or damp or wet chippings have prevented adhesion from taking place initially. Failure is sometimes localised and this then becomes tearing (see 3.8). NOTE 4 Minor random loss of chippings, which does not affect the homogeneity of the mosaic, is not considered to be fretting. This inc
45、ludes the initial loss of excess chippings used in construction that do not fit into the mosaic. 3.10 streaking loss of chippings from a completed surface dressing such that more than one line appears parallel to the direction of application NOTE 1 Lack of binder is the main cause of streaking and t
46、his may be caused by an irregular transverse distribution of binder across the spray bar. NOTE 2 Poor construction techniques such as insufficient overlap of binder spray at longitudinal joints may result in loss of chippings due to lack of binder. The appearance is similar to streaking though only
47、in one line, at a joint. 3.11 width of lane when there are no road markings, the lane width is the full road width; when there are road markings, the lane width is the distance between the centre marking and kerb or verge; and when there are more than two lanes, then the outside or centre lanes and
48、hard shoulder (safety zone) are considered separately 4 Visual assessment of defects 4.1 General A 100 m 1m section of surface dressing is chosen for visual assessment for each lane of the road (see 3.11 for definition of lane width). The section reference shall be recorded in the relevant annex. Sections may be located anywhere along the road except that they shall not overlap. The remainder of the site that is not chosen for test or the area between sections is deemed to be without defects at the time of carrying out the test. NOTE 1 The se
