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

Flow diagram for testing basecourse material

F u lfillsre q .?

A g g re g a te s fo r ba s e c o urs e ,de s ig n s ta g e

H um us c o ntent/p las tic ity

F u lfillsre q .?

y es

D o e s v is u a lin s p e c t io n in d ic a te

th a t th e a g g re g a te isfre e o f h u mu s a n d

n o n p la s t ic ?

n o

y es

n oS ieving analys is

Is th e a g g re g a tew ith in g ra in s ize

d is t rib u t io nlimit s ?

y es

n o

y es

y es

y es

n o

n o *

y es

n o

3 % o f th es a mp le 0,02

mm?

P a s s

5-6 % o f th es a mp le 0,063

mm?

H yd ro m eter-tes t

P e tro graphicanalys is

F u lfillsg u id in g

re q .?

S trength (LA )

F a il

If the s am ple fulf i l ls al l r e quire m e nts e xc e ptfo r grading, fur the r te s t ing, i .e . C B R - te s t c an

be c o ns ide re d

F reeze/thaw test

F ulf illr e q.?

C rus hed andb ro ken s urfac es

F u lfillsre q .?

S hap e (F I)

F u lfillsre q .?

y es

y es

n o

y es

n o

n o

X

X

* O n ly re qu ire d if th e 3 rd cla s s a g g re g a te is v e ry a lt e re d

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 13242Grading Characteristics EN 13242Example 0/32 mm material Example 0/32 mm material

0/32 G0/32 GAA8585

GGrading rading categorycategory

Refers to Refers to AAll inll in

Minimum 85% Minimum 85% passing D passing DSSize ize

designation designation d/Dd/D

Aggregate % < 0,063

mm

Category,

f

Coarse

(d > 1 mm

D > 2 mm)

≤ 2

≤ 4

>4

NR

f2

f4

fDeclared

fNR

Fine

(d = 0 mm

D ≤ 6,3 mm)

≤ 3

≤ 7

≤ 10

≤ 16

≤ 22

>22

NR

f3

f7

f10

f16

f22

fDeclared

fNR

All-in

(d = 0 mm

D > 6,3 mm)

≤ 3

≤ 5

≤ 7

≤ 9

≤ 12

≤ 15

>15

NR

f3

f5

f7

f9

f12

f15

fDeclared

fNR

EN 13242 (TC 154) EN 13285 (TC 227)Missing UF6,UF8

% passing 0,063 mm

Category,

UF

≤ 3

≤ 5

≤ 7

≤ 9

≤ 12

≤ 15

NR

UF3

UF5

UF7

UF9

UF12

UF15

UFNR

% passing 0,063 mm

Category,

LF

2

4

8

NR

LF2

LF4

LF8

LFNR

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)

Base course grading requirements

Crushed gravel requirements vs. EN 13285 (0/31,5)

0

20

40

60

80

100

0.01 0.1 1 10 100

Grain size (mm)

Pa

ss

ing

(%

)

GA

GB

GC

Base course grading requirements

Crushed gravel req. vs. EN 13285 (0/63)

0102030405060708090

100

0,01 0,1 1 10 100

Grain size (mm)

Pas

sin

g (

%)

GA

GB

GC

Base course grading requirements

Crushed rock req. vs. EN13285 (0/63)

0

10

20

30

40

50

60

70

80

90

100

0.01 0.1 1 10 100

Grain size (mm)

Pas

sin

g (

%)

GA

GB

GC

GO

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 in quality class 3

Road type Altered Fresh

A-B1 ≤ 7 ≤ 12 B2-B3 ≤ 10 ≤ 20 C1-C2 ≤ 15 ≤ 30 D ≤ 15 ≤ 30

Frost resistance in base course according to prEN 1367-6 if failed petrographic analysis

Other proposed Categories 2,4,20

Road type Freeze/thaw (%)

A-B1 ≤ 8B2-B3 ≤14C1-C2 ≤ 14D NR

Road type Crushed gravel Crushed rock

A-B1 C50/10 C90/3

B2-B3 C50/10 C90/3

C1-C2 C50/30 C90/3

D CNR/50 CNR

Crushed or Broken/Totally Rounded Particles Base course

Other EN13242 Category CNR/70 ,missing C50/20 ,C40/30

Flakiness Index, Base courseOther EN13242 Category none , missing FI15-25-30-40

Road type Flakiness index

A – B1 FI20

B2-B3 FI20

C1-C2

D

FI35

FI50

Road type Altered Fresh

A-B1 LA20 LA25

B2-B3 LA20 LA30

C1-C2 LA25 LA35

D LA30 LA40

Los Angeles requirements, Base courseOther EN13242 Categories LA50,LA60 ,missing LA15

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’

Thank you for your attention