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Roadstone Duraflex is a Hi PSV aggregate Stone Mastic Asphalt (SMA) surface course material. The aggregate composition and mix design gives it its inherent strength characteristics and increased resistance to rutting over and above that seen with Hot Rolled Asphalt.

Duraflex is a highly durable material with its surface texture meeting the requirements set out by the Transport Infrastructure Ireland (TII). The name was appropriately chosen to encompass both the durability and flexibility of the mix providing the customer with a long lasting product. It is primarily used for road surfacing for National and Non-National roads and urban streets.

Key features and benefits
  • Deformation resistance
  • High Strength
  • Reduced Tyre Noise
  • Compliance with NRA texture requirements
  • Durability
  • Available in a range of mixes
  • Made from local materials to the highest standards
  • 100% Recyclable
Technical Specification

Produced in accordance with

  • IS EN 13108-5 Stone Mastic Asphalt
  • NSAI’s Standard Recommendation (SR) 28
  • I.S. EN 13108-20: Type Testing and I.S. EN 13108-21: Factory Production Control
  • CC-SPW-00900 Transport Infrastructure Ireland’s, Series 900 Specification for Road Works
CRH Asphalt Research & Development Laboratory

Based in Roadstone headquarters in Belgard, CRH asphalt research & development laboratory was established with the objective of researching new and existing asphalt mixes and to develop products and processes to enhance the CRH groups leading position in Asphalt technology.

The development of harmonised product standards and test standards by CEN (Comite European de Normalisation) has placed a greater emphasis on material performance and out performing the requirements of these standards has been a major focus.

With a comprehensive range of test equipment available we can measure a wide  range of material characteristics including stiffness, fatigue and permanent deformation, by both Swedish Indentation and Vacuum Tri-Axial methods.  Aggregates, Bitumens and Fillers are also tested in the laboratory.

The Laboratory has performed a large number of material designs over the last few years such as Porous Asphalt (M50), Marshall Asphalt (Dublin & Shannon Airports) and a large range of Thin Layer Asphalts (NRA Motorways).  Comprehensive design protocols have been established in the laboratory for various material types which ensure that end performance requirements are achieved.  The laboratory has also developed new materials which offer solutions and a wider choice to our customers. The tests performed in the laboratory are accredited by the Irish National Accreditation Board (INAB).

With the introduction of the EN13108 series of Bituminous product standards there is now a requirement for our products to be Type Tested. This type testing can incorporate performance testing and this is done in the CRH Asphalt Laboratory. Guidance on current Type Test requirements is given in Standard Reccomendation(SR) 28- Standard Reccomendation for the use of the EN 13108 series.