Evolution in the context surrounding French highway projects was significant at the end of the 20th Century. This evolution involved increasing constraints, primarily environmental (reflected by legislation such as the law on water, etc.) and economic, as well as concerns for the safety of both users and operators. These developments influenced strongly the body of engineering literature (guides, codes, etc.), which was fundamentally renewed and complemented during the final decade. Moreover, "standards" are today increasingly questioned. This may be explained by changes in the contexts--institutional, socioeconomic, and legal--surrounding their utilization. Positions require explanation if they are to be accessible, understood and ultimately accepted by all players. Formal presentation of justifications satisfies a number of aims: reinforcing the credibility of recommendations, enhancing their appropriation, favoring their enlightened application, facilitating their maintenance and subsequent development. In concrete terms, this is reflected in a number of ways: direct inclusion of justification in guides, drafting of specific explanatory documentation or, again, compilation of answers to all the (very numerous!) questions raised during consultation phases involving the whole engineering community. A number of recent French publications bear witness to these developments.
Abstract