Superstrade urbane. Dall’alta velocità alle trasformazioni contemporanee

This article focuses on urban freeway deconstruction processes that recognize this infrastructure as a resource to be reclaimed for urban regeneration. Since they first appeared, freeways have been more than simple carriers of traffic flow. Following the suggestions provided by Le Corbusier, Drexler and Rudofsky in their “ROADS” exhibition, Lawrence Halprin, Reyner Banham, particular attention is paid to the shift towards a larger set of aesthetic assumptions applied to highways. Fifty years after the iconic evocation of Autopia, urban freeways no longer embody the modern value of speed: they must increasingly deal with ecological challenges and re-cycling processes. The nodes where infrastructure comes together with architecture and public space are explored in a rapid survey of case studies. At a metropolitan scale, the recent cases of the Central Artery in Boston or the Cheongyeccheon expressway in Seoul, demonstrate unprecedented efforts in urban design, in which at the core of a multifaceted redevelopment project the highway disappears, replaced by a ground-level boulevard. This trend, seen earlier in San Francisco or Portland, differs from the situation in Europe, which raises a case -to-case approach. The Concrete Collar in Birmingham, or the many studies on the Périphérique in Paris, seek to implement specific actions the purpose of which is to resolve fractures in the urban fabric, issues involving linear voids along the edges, and lacerations in the urban continuity, in an attempt to reinvent the often adverse qualities of this infrastructure by relying on the architectural ambition of infrastructural design.