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This presentation summarizes the implementation of CEN Standards by the Icelandic Road Administration, focusing on product standards for unbound aggregates and mixtures. It discusses the challenges, guidelines, and testing requirements outlined in EN 13242 and EN 13285, emphasizing the importance of harmonizing grading practices. Additionally, it touches upon the need for a mechanistic approach in EN 13285 and the significance of complying with European standards in the regulatory context of the European Union.
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Implementing CEN Standards in Icelandic Road Guidelines Gunnar Bjarnason Icelandic Road Administration (ICRA) CEN-NORD, Reykjavík 29.09. 2006
Main Focus on two Product Standardsfor unbound aggregates and unbound mixtures • EN 13242 (TC 154 Aggregates) Aggregates for Unbound and Hydraulically Bound Materials in Civil Engineering Work and Road Construction • EN 13285 (TC 227 Road Materials) Unbound Mixtures Specification
ICERA decided against using EN 13242 for grading requirements • The EN 13242 Standard does not give detailed grading limits for road layers • The standard gives the producer guidelines on how to classify aggregates and requirements on undersizes and oversizes • Requirements for other unbound aggregate properties are however mostly in accordance with the categories of EN 13242
Grading Characteristics EN 13242 Example 0/32 mm material 0/32 GA85 Minimum 85% passing D Size designation d/D Grading category Refers to All in
EN 13242 (TC 154) EN 13285 (TC 227) Missing UF6,UF8
EN 13285 Unbound Mixtures • Not a Harmonised Standard which means no CE marking • Specifies grading categories with considerable choice. • Difficult to find direct equivalents for grading to some of our existing basecourse and subbase requirements. • Only “all in” 0/8-0/80 but not for example 0/90, 0/125 or graded or single sized although the standard covers both basecourse and subbase materials. • No limits in the grading range 0,063 – 0,5 mm • Aggregate properties in accordance with EN 13242 • Article 4.5: Under certain conditions frost susceptability, permeability and leaching shall be considered. • Does not include Mechanical Behavior of Unbound Mixtures (stiffness, permanent strains)
Assessment of fines EN 13242In Annex A (normative) • Fines <3% of the fine aggregate then nonharmful • Sand Equivalent, • Methylene Blue
Assessment of fines ICRAallowed by Article 4.5 in EN 13285 • Article 4.5: Requirements may be given in regulations in the place of use based on direct or indirect assessment of frost susceptibility and frost heave • Fines ≤ 0,02 mm ≤ 3% determined by hydrometer or laser methods • Organic matter (Humus content) NaOH, • Plasticity of fines PI, LS
Petrographic analysisBase course “guiding requirements” Maximum percentage inquality class 3 Road type AlteredFresh A-B1 ≤ 7 ≤ 12B2-B3 ≤ 10 ≤ 20C1-C2 ≤ 15 ≤ 30D ≤ 15 ≤ 30
Frost resistance in base course according to prEN 1367-6 if failed petrographic analysisOther proposed Categories 2,4,20 Road type Freeze/thaw (%) A-B1 ≤ 8B2-B3 ≤14C1-C2 ≤ 14D NR
Crushed or Broken/Totally Rounded Particles Base course Other EN13242 Category CNR/70 ,missing C50/20,C40/30 Road typeCrushed gravel Crushed rock A-B1 C50/10C90/3B2-B3 C50/10C90/3C1-C2 C50/30C90/3D CNR/50CNR
Flakiness Index, Base courseOther EN13242 Category none , missing FI15-25-30-40
Los Angeles requirements, Base courseOther EN13242 Categories LA50,LA60 ,missing LA15 Road type Altered Fresh A-B1 LA20LA25 B2-B3 LA20LA30 C1-C2 LA25LA35 D LA30LA40
Mechanical Behavior of Unbound MixturesNot yet part of EN 13285 (Annex C informative) • At ICERA we have used • CBR test (requirements) • Laboratory Plate Bearing Test (requirements) • Repeated Load Triaxial Test (for research)
Do we have to use European Standards Test Methods? • According to the Mandate M 125 alternative test methods can be used provided that good correlation can be demonstrated with the reference method • Example Optical Measuring Equipment to measure particle shape in stead of Flakiness index method
Some Conclusions • The Categories of EN 13242 are in most cases adequate for road aggregates but the grading categories are not • The grading Categories of EN 13285 could be improved to cover all base course and subbase mixtures • It is important to make the EN 13242 and EN 13285 grading requirements compatible • Mechanistic approach should be added to EN 13285 • It is important that the Nordic Freeze Thaw Test has been accepted and will be part of the EN 13242 Product standards.
Why European standards? • Not because industry wants to • Not because specifiers want to • Not because they are better standards • Because it is part of the regulatory framework of the European Union to remove ‘barriers to trade’