bituminous binders. Regulations and prospects
- Highways Magazine No. 157 - January / February 2008
Yves Brosseaud
Section Chief auscultation and Road Management,
Laboratoire Central des Ponts et Chaussées (LCPC, Nantes, France)
Vincent Gaudefroy
Research commissioned in Section Roadway Binders and Materials
Laboratoire Central des Ponts et Chaussées (LCPC, Nantes, France)
Alain Beghin
Frédéric Placin
Researchers in Section Roadway Binders and Materials
Laboratoire Central des Ponts et Chaussées (LCPC, Nantes, France)
Frédéric Delfosse
Engineering Research Center (EUROVIA, France)
José Miguel Baena
ADG Urban Spaces.
Government Department of Works and Public Spaces. Ayto. De Madrid
(Chief Technology and Area Studies of CEDEX roads during the project)
ABSTRACT
Within the SCORE ( "Superior Cold recycling of asphalt pavements"), the 5º framework program for research and development of the European Commission, the Laboratoire Central des Ponts et Chaussées (LCPC) project was the leader of the 7 task, which is the evaluation of mechanical properties in laboratory recycled in situ through cold techniques. Before the study, was an essay on the determination of indirect tensile modulus between laboratories involved in this work to evaluate the dispersions in both sample preparation and on the test itself.
one reference gravel-emulsion 160 / 220, a level close to the cold materials module was chosen. Having prepared with the help of the rotary press (PCG), cold-recycled samples with work comparable to physical characteristics, maturation takes place in a climatic chamber at controlled relative humidity. From these samples PCG cylindrical, parallelepiped sawn and some samples are subjected to a complex test flexural modulus in 2 points.
The various cold mixes tested are: regular emulsion, micronised emulsion ( "nanoemulsion") and foam bitumen. 2 compared to material witnesses: traditional gravel bitumen emulsion and gravel with soft bitumen. the influence of the nature of recycling is evaluated, granulometric composition and void content. resistance to rutting, fatigue resistance on plate corresponding to a track test and modeling attempt this test: a study on the potential of other mechanical tests began.
This article presents the main results obtained on measuring the complex modulus of bituminous materials at low stiffness.
KEYWORDS:
Emulsion, nanoemulsion, Foam bitumen, bituminous binder, Gravel emulsion, module, SCORE.