BS EN 12697-2:2015 pdf download – Bituminous mixtures — Test methods Part 2: Determination of particle size distribution
1Scope
This European Standard specifies a procedure for the determination of the particle size distribution of theaggregates of bituminous mixtures by sieving.The test is applicable to aggregates recovered after binderextraction in accordance with EN 12697-1 or EN 12697-39.
The applicability of this European Standard is described in the product standards for bituminous mixtures.NOTE Fibres, solid (non-soluble during extraction) additives and (some) binder modifiers influence the test result.
2Normative references
The following documents，in whole or in part,are normatively referenced in this document and areindispensable for its application.For dated references, only the edition cited applies. For undated references,the latest edition of the referenced document (including any amendments) applies.
EN 932-6,Tests for general properties of aggregates — Part 6: Definitions of repeatability and reproducibility
EN 933-1,Tests for geometrical properties of aggregates — Part 1: Determination of particle sizedistribution – Sieving method
EN 12697-1,Bituminous mixtures —Test methods for hot mix asphalt — Part 1:Soluble binder contentEN 12697-39, Bituminous mixtures —Test methods for hot mix asphalt — Part 39: Binder content by ignitionISO 3310-1,Test sieves —Technical requirements and testing — Part 1:Test sieves of metal wire cloth
ISO 3310-2，Test sieves — Technical requirements and testing — Part 2: Test sieves of perforated metalplate
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
particle size distribution
portion of aggregate on specified sieves expressed as cumulative percentages by mass passing those sieves
3.2
upper sieve size of the aggregate in the bituminous mixture in millimetre (mm) according to the relevantmaterial specification standard
4Significance and use
The composition of a bituminous mixture in terms of binder content and aggregates grading is a significantquality parameter. The European Standard for bituminous mixtures contains some grading specifications.Controlling the mixture grading is an important instrument for product quality management.
5 Principle
The test consists of the determination of the particle size distribution of the aggregates in the bituminousmixture by sieving and weighing.A granulometric analysis of the aggregate is performed after binderextraction.
6 Apparatus
6.1Unless stated otherwise, the apparatus as required in EN 933-1 shall be used.
6.2Sieves with aperture size up to and including 2,8 mm shall be in accordance with ISO 3310-1.6.3Sieves with aperture size of 4 mm and larger shall be in accordance ISO 3310-2.
7 Sample preparation
The test shall be carried out on the material recovered after completion of the test as specified inEN 12697-1or EN 12697-39.
lt should be ensured visually that all aggregate is recovered from the mixture and that no binder remainedadhering.
The recovered aggregate shall be dried to constant mass. Particles shall be separated completely.
NOTE1“Constant mass” is defined as successive weighings after drying at least 1 h apart not differing by more than0,1%.
NOTE 2 Other regimes for achieving constant mass can be used provided that they can demonstrate that they give thesame results as drying at (110±5).c.
8Procedure
The test shall be carried out on the aggregate according to EN 933-1. When less material to be tested isavailable than required in this European Standard,the total amount of material available shall be tested.However the minimum amount of material shall be the lesser of 50 D g and 1 000 g.
When the aggregate is visually greasy after carrying out the test in accordance withEN 12697-1, a decrementof the surface tension may be required by adding some peptizing additive.
When this test is carried out after a binder extraction procedure in which a sieving stage is incorporatedcontaining the applicable sieves, and when the aggregate is thoroughly washed during the execution of testEN 12697-1，or when the aggregate remains from EN 12697-39，the particle size distribution may bedetermined by dry sieving only. However,where the proportion of material passing the 0,063 mm sieveremaining with the aggregate is found to be greater than 1,0 % of the total aggregate,the particle sizedistribution shall be re-determined after washing the aggregate.
lf the aggregate has already been washed, the effectiveness of re-washing should be considered.
lf one size portion contains visually different aggregate types, this variation should be reported and the typeaggregate shall be described.