Relation between CEN standards and performance based operations by sGKO4fN

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									Relation between
 CEN standards
and performance
based operations
By JP Michaut Colas’ Group
 What are the raised issues by the
  implementation of the European
standards for aggregate and asphalt
      concrete in tendering ?
Asphalt concrete




  WG1 /TC227 meeting in Berlin
    What asphalt standards ?

                 The figures

   7 European product standards
   1 Reclaimed asphalt standard
   1 Type testing standard
   1 Factory production control standard
   43 test standards
European asphalt standards

   Asphalt Concrete             13108-1
   Very Thin Asphalt Concrete   13108-2
   Soft Asphalt                 13108-3
   Hot Rolled Asphalt           13108-4
   Stone Mastic Asphalt         13108-5
   Mastic Asphalt               13108-6
   Porous Asphalt               13108-7
  European asphalt standards

 Reclaimed asphalt or so called RAP    13108-8
 Type testing                          13108-20
 Factory production control            13108-21

 and one new European standard for Ultra Thin
 Asphalt Concrete (BBUM) ?
          Asphalt concrete
 From thin asphalt concrete to EME, from
  dense bitumen macadam to HDM and HMB
  and other AC (from 4 to 15 cm thick by layer)
 One only standard for base, binder and
  wearing courses
 2 approaches: empirical or fundamental



      For the other standards
  One   empirical standard per product
    Empirical or fundamental ?
 Empirical = recipe
 Performances related specifications
  (rutting)
 Fundamental = stiffness modulus,
  fatigue and triaxial
 Performances based specifications


   But may be we can speak just about
    performance and specification
                     What content ?
   General requirements (grading, void content, water
    resistance, rutting, etc.)
    You can choose
   Empirical (range for grading, binder content, Marshall
    only for airfield, void filled with binder, etc.)
    You can choose
   Fundamental (modulus, resistance to permanent
    deformation by triaxial test, fatigue)
    You can choose


   But do not forget that european standards does not
    take into account laying.
             Fundamental approach

   One specification is the minimum binder
    content
       greater than 3 %
   One other is the limit of target
    composition
       range for main sieves (1.4 D, D, 2 mm,
        0.063 mm)
   With fundamental approach, you can
    propose design alternative by using the
    real mix performances such as stiffness
    and fatigue

   But we must have performances for all
    mixes
 What changes due to type
         testing?


Type testing or how to prove that
 asphalt concrete meets standard
           requirements
   A single mix formulation is valid for 5 years except if
    changes in aggregate (category, particle density, etc.)
    or in bitumen

   Laboratory validation
                             or
    Production validation
                            or
    Production and laboratory validation

   List of tests per product to carry out to
    demonstrate standard conformity

   One test for one property
     What changes due to the
    factory production control ?

   Systematic production control


 More or less control for certain mixing
 plants
    Factory production control

 Based on quality assurance (ISO 9001)
 Based on detailled analysis of the mix

 Depending of non conformities (figures
  outside tolerances), level of minimum
  frequency for analysis of finished product
 Level fo frequency fixed by the standard
  (more or less numerous)
 Guide for audit by notified body is in the
  standard
   Before works, you have to prove that
    your mix meets the standard
    requirements: this is type testing
   During works, you have to check asphalt
    manufacturing : this is factory
    production control (loose mix)
   But for laying, you have to prescribe the
    controls or the performances you want :
    this is the contract.
        To conclude for asphalt

   En asphalt standard will be published in
    April 2006
   Withdrawal of all national asphalt
    standards in December 2007
   You have to write your national
    forewords and also may be a guide to
    describe your choice
And for aggregate

       Already applied since July 2003



       Withdrawal of national standard
       Since June 2004


       Just one only standard
         Four parts

1.   Aggregate characteristics and
     specifications
2.   Initial type testing or How to prove
     that the aggregates meet the
     standard requirements
3.   Factory production control
4.   And a national foreword
           Characteristics and
             specifications
   Sieve sizes (3 possibilities)
           Basic set, basic set + set 1 or basic set + set 2


   Grading

   Choice of physical or manufacturing
    characteristics and choice of
    specifications or not
      Initial type testing

   For a new source

   Major change in the nature of the
    raw materials or in the processing
    conditions

   But in fact, tests used are those for
    factory production control
    Factory production control

   Based on quality assurance
   Minimum test frequency are
    specified, examples:
     Grading:one per week and per size
     Shape of coarse aggregate: one per
      month
   And one audit by notified body
              What differences ?

   Grading : perforated sieves
    and not wire sieve (adaptation
    or interpretation issue ?)
   Example: 4/6.3 mm control (1.4
    D) or 8.82 mm
   Close sieves in set 2 are 8 and
    10
   But ISO 565 , R20 set: 9 mm ?
   Then which one to choose ?
                But are they ?
1.   Well known asphalt concrete formulation
2.   Keep the same composition (x% of each
     constituant)
3.   Grading curve with perforated sieve
4.   New grading curve
5.   But always the same formulation and
     composition

Wide grading : no difference
Narrow grading : light difference

         You have to do your own experience
       But also some difficulties
   Measurement of aggregate particle density
    before and after: not the same results
   Some standards are already reviewed due
    to mistake, difficulty for performing test,
    etc (in progress)
   Conformity criterias are missing
    Positive and negative effects !!!

   In Europe, we will speak the same
    language and we will use the same test
    methods (PE)
   Each mix has to be checked every 5
    years (PE)
   Each mix of each mixing plant has to
    have a type testing (PE)
   Factory control more efficient based on
    regular frequency production (PE)
      Positive and negative effects and
                   others !!!

   Difficulty to understand european
    standards and hence the need to have a
    national foreword (NE)
   Need a fundamental approach for each
    product (porous asphalt, SMA, etc)
   Need to describe the performances for
    laying (in terms of compacity or others)
                  To conclude
   En asphalt standard will be published in April
    2006
   Withdrawal of all national asphalt standards
    in December 2007
   Writing of national forewords in progress for
    certain countries


And good luck for implementation
       in your contracts

								
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