Materials and Conformity - Mineral Products …

1 The process of implementationof European StandardSpecifications (EN s) for asphaltin the UK is well underway andthe BSI Committee and WorkingParty responsible for draftingguidance on implementation andsupporting Standards have beenworking hard to ensure that theEN s are made easy tounderstand and use. The wholepackage of EuropeanSpecifications and Test Methodsfor asphalt, together with theNational Guidance Documentsand revised standard for asphaltlaying will be implemented on1 January fundamental aim of the implementationprocess is to ensure that, as far as possible,traditional UK asphalt mixtures are retainedunchanged. However, the implementationprocess will result in a number of changesto the way in which asphalt Materials arespecified and, more specifically, in the wayin which the Materials are described StandardsAsphalt Materials have traditionally beenspecified in the UK by British Standards BS594 for Hot Rolled Asphalt, BS 4987 forCoated Macadam and BS 1447 for MasticAsphalt.

2 These Standards will be withdrawn infavour of the BS EN 13108 series, whichcurrently incorporates seven materialspecifications, one constituent materialspecification and two standards relating toEvaluation of 1 highlights the BS EN 13108 family ofstandards and their relevance to andConformityAugust 2007 INFORMATION ON NEW EUROPEAN STANDARDSASPHALTQPA Asphalt Group Bulletin21 Asphalt concreteMajor importanceincludes coated macadams, DBM, HDM concrete for Importantbut in practice thin surfacings will be dealt with by BBA HAPAS system certificationvery thin layers3 Soft asphaltNo relevancesoft asphalt is not used in the UK4 Hot rolled asphaltMajor importancecovers all HRA5 Stone mastic asphaltImportantfor specified SMA although most SMA type thin surfacings will be covered by BBA HAPAS asphaltImportantbut guidance to be provided by Mastic Asphalt Council7 Porous asphaltLimited relevancebecause of dwindling use of porous asphalt on highways8 Reclaimed asphaltImportantfor classification of reclaimed asphalt when used as a constituent material in fresh asphalt20 Initial Type TestingVery importantin relation to determination of material properties and declaration of compliance21 Factory production Very importantin

3 Relation to quality assurance and declaration of conformitycontrolEN 13108 Part Relates to Relevance to UKTable 1 The National Guidance Document on the useof BS EN 13108 is published by BSI asPublished Document PD 6691 and has beendrafted to contain all the relevant informationrequired for specifying and producing asphaltmaterials. This includes guidance on constituentmaterials, performance classes for specifiedmixture characteristics temperature, voidcontent, stiffness etc., as well as a series ofAppendices containing example specificationsfor traditionally specified UK asphaltmaterials. The Materials which are explicitlyconsidered in PD 6691 in view of theirimportance in the UK are: Asphalt Concrete,Hot Rolled Asphalt, and Stone Mastic 6691 will be of as much, if not more,relevance to specifiers and producers ofasphalt as the material EN s second BSI Published Document, PD 6692,provides guidance on the use of the EN TestMethods for asphalt which are called up byBS EN Conformity requirements of FPC and TypeTesting have been integrated into SectorScheme MaterialsWhile the intention is that implementation ofthe EN13108 series will not significantlychange the mixtures themselves, there aresome necessary changes to be adopted,notably in product descriptions and mixturenomenclature.

4 Product descriptions are brokendown to identify the mixture type, maximum(nominal) aggregate size, the pavement layerin which it is used, and the binder grade usedin the mixture, as indicated in Table 2 typeSizePavement layerBitumen grade 40/60 Table 2 ACDbase/bin/surfbinder (xx/yy)HRAgrading designationbase/bin/reg/surfbinder (xx/yy)SMAD base/bin/reg/surf binder (xx/yy)KeyACdenotesAsphalt ConcreteHRAdenotesHot Rolled AsphaltSMAdenotesStone Mastic AsphaltDdenotesaggregate sizebasedenotesbase (course)bindenotesbinder courseregdenotesregulating course (for HRA and SMA)surfdenotessurface coursebinderdenotesfull bitumen grade designation PD 6691 retains some of the traditional BSnomenclature including additional mixturedescriptors for Asphalt Concrete that betterdescribe the grading or texture of many ofthose (macadam-type) Materials dense,open, medium (graded), heavy duty etc.

5 , andin the case of HRA, the mixture designationshave reverted to those used in BS594 beforethe 2003 revision, removing the % all Materials , the bottom-end sieve hasbeen removed from material full range of material optionsrecommended in PD 6691 is shown in Table 3opposite. Materials shown in boldarepreferred mixtures as highlighted in BS 4987& concrete mixtures complying with EN 13108-14mm Fine graded surface courseAC 4 fine surf160/220250/3306mm Medium graded surface courseAC 6 med surf160/220250/3306mm Dense surface courseAC 6 dense surf70/100100/150160/220250/33010 mm Open graded surface courseAC 10 open surf160/220250/33010mm Close graded surface courseAC 10 close surf70/100100/150160/220250/33014mm Open graded surface courseAC 14 open surf160/220250/33014mm Close graded surface courseAC 14 close surf70/100100/150160/220250/33020mm Open graded binder courseAC 20 open bin160/220250/33020mm Dense, heavy duty and high modulus binder course AC 20 dense bin40/6070/100100/150160/220AC 20 HDM bin40/60AC 20 HMB bin30/4532mm Dense.

6 Heavy duty and high modulus binder course AC 32 dense bin40/6070/100100/150160/220AC 32 HDM bin40/60AC 32 HMB bin30/4532mm Dense, heavy duty and high modulus base AC 32 dense base40/6070/100100/150160/220AC 32 HDM base40/60AC 32 HMB base30/4510mm EME2AC 10 EME2 base/bin10/2015/2514mm EME2AC 14 EME2 base/bin10/2015/2520mm EME2AC 20 EME2 base/bin10/2015/25 material descriptionEN 13108 designationBitumen Grade optionsTable 3 Hot Rolled Asphalt mixtures complying with EN 13108-4 HRA 50% 10mm for regulating or binder courseHRA 50/10 regHRA 50/10 binHRA 50% 14mm for regulating or binder courseHRA 50/14 regHRA 50/14 binHRA 50% 20mm for base or binder courseHRA 50/20 baseHRA 50/20 bin HRA 60% 20mm for base or binder course HRA 60/20 base HRA 60/20 binHRA 60% 32mm for base or binder course HRA 60/32 baseHRA 60/32 binHRA 0% 2mm Type F Surface Course (Sand carpet)

7 HRA 0/2 F surfHRA 15% 10mm Type F Surface Course HRA 15/10 F surfHRA 30% 10mm Type F Surface Course HRA 30/10 F surfHRA 55% 10mm Type F Surface Course HRA 55/10 F surfHRA 30% 14mm Type F Surface Course HRA 30/14 F surfHRA 35% 14mm Type F Surface Course HRA 35/14 F surfHRA 55% 14mm Type F Surface Course HRA 55/14 F surfHRA 0% 2mm Type C Surface Course (Sand carpet)HRA 0/2 C surfHRA 55%10mm Type C Surface Course HRA 55/10 C surfHRA 30% 14mm Type C Surface Course HRA 30/14 C surfHRA 35% 14mm Type C Surface Course HRA 35/14 C surfHRA 55% 14mm Type C Surface Course HRA 55/14 C surfStone Mastic Asphalt surface course mixtures complying with EN 13108-56mm SMA Surface CourseSMA 6 surf40/6010mm SMA Surface CourseSMA 10 surf70/10014mm SMA Surface CourseSMA 14 surf100/150 Other Stone Mastic Asphalt mixtures complying with EN 13108-56mm SMA for regulatingSMA 6 reg10mm SMA for regulatingSMA 10 reg14mm SMA for regulating or binder courseSMA 14 reg/bin20mm SMA for regulating or binder courseSMA 20 reg/binMaterial descriptionEN 13108 designationBitumen Grade options Preferred options highlighted in the designation in column 2 with the binder grade in column 3

8 Gives the minimum recommended product :PSV will also be included in the product description where of the most fundamental changes fromthe previous British Standards is the movewithin the EN s from an empirical/recipespecification to a declared target plustolerance approach. This is similar to theapproach used in SHW Clause 929 andpermits a wider degree of freedom forproducers to design Materials for performancerather than be constrained by a strictcompliance of ConformityThe evaluation and demonstration of theconformity of asphalt mixtures with therequirements of the European asphaltstandards is covered by two standards in theEN 13108 series: BS EN 13108 - 20 Type Testing BS EN 13108 - 21 Factory Production ControlThey spell out, in some detail, the obligationsof a producer of asphalt, in order to make adeclaration that the material conforms to aparticular specification drawn from one of theEN 13108 requirementsapply, and are identical,whether or notCEMarking is to be Type TestingInitial Type Testing (ITT) is a procedure inwhich a given mix formulation (targetcomposition and set of constituents) is putthrough a series of tests to prove that itcomplies with the detailed specificationrequirements, in particular any performancerelated properties, with which Conformity isbeing claimed.

9 Every detail and property has tobe validated - even for simple recipe mixtures,although here of course there will be fewerrequirements to demonstrate. This is similar toa combination of a technical file, a mix designreport and/or a job standard mix trial addition to laboratory testing or approval ofconstituents, Type Testing will includeassessment of properties of plant mixedmaterials laid in trials, following protocols laidout in the new Standard for Asphalt Laying andCompaction: BS594987. Properties such asinsitu air voids, resistance to permanentdeformation and stiffness can be determinedfrom Materials extracted from trial result of a Type Testing procedure is a TypeTest Report. This is a formal document whichrelates only to the formulation which has beentested and is required as proof that thatformulation complies with the relevantspecification detail.

10 The Type Testing is mixturespecific, the same mixture can be producedon a number of Production ControlFactory Production Control (FPC) is, in essence,a schedule for a quality system to ensure that,at the asphalt plant, a mix formulation whichhas already been Type Tested is manufacturedconsistently in Conformity with requirementssuch as temperature and that the compositionof the mixed material is within certaintolerancesof the target. It does not includerequirements for measuring performancerelated properties of the asphalt other than arequirement that the validation carried outunder initial Type Testing should be repeated atleast at five yearly intervals. It is very similar inconcept and in content, to the SectorScheme 14 Schedule and will replace most ofthe detailed requirements in an updatedSector 14 Compliance Level (OCL)EN 13108-21 FPC uses a measure ofconformity known as Operating ComplianceLevel.