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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 Standards for unbound aggregates and unbound mixtures.
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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’