Groupe CB

CONTRIBUTING TO WORK EFFICIENCY

Because they come from quarries of massive rocks, by their nature, their neatness and their cubic form, the aggregates from Carrières du Boulonnais , dry or washed, offer an ease of use in ready-mix concrete and prefabricated concrete, while optimizing the following parameters :
- consumption of cement
- workability of concrete
- abrasion of tools
- mechanical resistances at early age
- mold release times

Because of their non alcali-reactive character, all of the materials, sand and gravel, are perfectly suited for the construction of any type of civil engineering structures.

Sands

Dry :
Dry sand 0/4 mm with 10 % fines
Dry sand 0/6 mm with 10 % fines

Washed :
Washed sand 0/4 mm with 3 % fines
Washed sand 0/4 mm with 7 % fines

Gravels


Dry :
Dry gravel 12/31 mm
Dry gravel 10/14 mm

Washed :
Washed gravel 02/04 mm
Washed gravel 04/10 mm

General characteristics of limestone aggregates calcaires

(XP P 18-545 & NF EN 12620)

Nature : Massive, dense carbonate rock

Source: Visean basin of Bas Boulonnais

Compression failure : 140 to 200 MPa

Coefficient Los Angeles (LA) : 22

Coefficient Micro-Deval (MDE): 13

Water Absorption ratio: 1 %

Aggregate resistant to freezing – thawing

Volumetric weight: 2.7 T/m3

Bulk volumetric weight :

Sand : 1.6 to 1.7 T/m3

Gravel, pebbles and rocks : 1.4 to 1.5 T/m3

Cleanliness of sand: Blue dye absorption test : MB < 1.5

Cleanliness of gravel : fines 63 µ < 1.5 %

Gravel flattening ratio : < 15

Active alkalines content : Na20 éq < 20mg/kg

Color : grey/beige

Humidity : between 0 and 6 %