An alternative to high modulus mixtures MAM for basecoats, long-term, economically efficient and eco-friendly

François Olard
Director R & D. EIFFAGE Travaux Publics 

Jérôme DHERBECOURT
Technical manager. EIFFAGE Travaux Publics

Hervé DUMONT
Technical director. EIFFAGE Travaux Publics 

M. Elena HIDALGO PÉREZ
Director R & D + i. EIFFAGE Infraestructuras

ABSTRACT 

The innovative design is based on GB5® mixture adaptation process bituminous mixes granular packaging optimization initially developed in the field of high performance concretes. These mixtures are characterized by discontinuous mixtures (with single or double discontinuity) with a large contact between coarse aggregate, which gives them an excellent dense mineral skeleton, with high internal friction and high mechanical strength, without resorting to the use of bitumens hard to meet the requirements of high stiffness (MPa 11.000 20 ° C) or the content of binder mixtures own high modulus.

This lesser requirement allows the binder content using polymer-modified bitumens in the base layers, on a percentage of the 4 4,5% on aggregate, thus leading to the GB5® mixtures characterized by high compactness, high modulus stiffness and high fatigue resistance, all simultaneously in a single mixture, allowing firm thickness reduction while durability. And all this ensuring the economic viability of this solution to the base layers.

Thus, the proposal GB5® can be considered as very interesting for long-term sustainable pavements that do not deteriorate structurally and only require periodic maintenance of the surface layer solution.

The design of this innovative mix has been presented in the "EuropeanRoadsReview Magazine" (www.rgra.fr)^{(I and II)}.

This article focuses mainly on the achievements in the use of this material in various works executed in France during the year 2011^(II)As well as a campaign of strain measurement instrumentation carried out in the year 2012^(XXIV).

KEYWORDS
High modulus mix, GB5 mix, Eco-friendly, Durability, Fatigue resistance.