Relational innovations, new services offers and transport infrastructure enhance value. The cases of a multimodal platform and a high speed rail service[Innovations relationnelles, nouvelles offres de service et valorisation des nouvelles infrastructures de transport. Le cas d'une plateforme multimodale et d'une desserte TGV]

The relationship between transport infrastructure and local development has been the subject of many controversies. If the systematic character of the effects has been questioned and the need for accompanying strategies emphasized, the latter ones are not a sufficient condition. However, in some cases, there is a relationship between infrastructure existence and local development. The aim of this article is to clarify the conditions under which this relationship might exist by using economic analyses of services. Transport infrastructures are then analyzed through the service offer which is directly associated to their presence (transport or logistic services) or indirectly (additional services production). But beyond the services themsel-ves, we propose to analyze the conditions of their production which can, according to us, facilitate their appropriation by local actors. More specifically, we wish to emphasize the relational innovations importance (new relations between the actors) in the production process of these services. These possible relational innovations (like co-operation between various public actors and/or various private actors and/or public and private actors) seem to be central in the possible positive effects of the infra-structures. This theoretical framework is then confronted with two cases: a multimodal logistic platform in Dourges and a high speed rail service in Reims.