An experimental bridge con tructed f l~ igh-~ trength concret~ ha been built at Joigny, France. The project 1s pa~ t. of a nation~! research program bringing together the Frenc~ Mmtstry o~ Pub. he W rk and Ministry of Research, the cement mdustry, umvcrstty and state laboratories and professional associations and institutions. The bridge ha's been instrumented in order to verify its long-term behavior and its durability in comparison with that of ordinary concrete bridges.

In 1985 the French Ministry of Public Works, in association with the Ministry of Research, launched the so-called Projets Nationaux de Recherche et de Developpement (National R&D Projects) in the field of civil engineering. One of these projects was devoted to Voies Nouvelles du Materiau Beton (New Developments for Concrete). The objectives of this project are clearly defined by its title: to identify and develop new ways to use the materials that make up concrete. The objectives of this project can be achieved through construction of experimental structures based on preliminary applied research and through instrumentation of these structures. The implementation of this project is based on four leading principles: