La conservation du patrimoine urbain, catalyseur du renouvellement des pratiques urbanistiques? Une reflexion theorique sur l'appropriation de la notion de patrimoine urbain par l'urbanisme

摘要

This thesis questions the contribution of heritage conservation to urbanism.;It has been proposed that the association between heritage conservation and urbanism in their present conceptual framework, rather than being the catalyst for rethinking urban projects has perpetuated a sectoral approach and atomization of human settlement, thus entrenching the functionalist paradigm that still largely conditions contemporary planning practices, notably in Quebec.;Indeed, although heritage conservation has been a recurrent theme since the 1960s in the redeployment of town planning skills, several studies have underscored the mitigated results of numerous conservation attempts and also of the limited contribution made to the planning of urban projects.;More specifically, in spite of the interest in heritage conservation and the potentially fertile nature of the idea of heritage generally, urbanism has not yet defined the terms of the contribution, not only from a conceptual point of view but also from a urbanistic point of view with respect to its project-based thinking (progettualita). Consequently, urbanism does not succeed in overcoming the heritage idea of the preservation register in order to fully encompass it.;This thesis explains the causes of this inability from an analysis of the conditions for adopting the notion of urban heritage as advanced by Giovannoni. This fundamentally urbanistic approach puts forward a concept of urban heritage that has freed itself from the historical monument of the preservation register. Inseparable from an urbanistic project-based system, the interest for Giovannoni's urban heritage arises from a recognition that what already exists creates a means for grasping the true personality of place and therefore offers insight for better urban design and planning.;Giovannoni's idea of urban heritage becomes the basic element of an urbanistic morphological analysis that allows for the conceptualization of the modern city as an entity marked by ruptures and discontinuities. Giovannoni exploits the differences in the personality of urban entities, such as places, neighbourhoods, etc., and visits back and forth between different scales and registers, those of forms and forces, of the existing and the hoped for, of ideas and action. Giovannoni thus goes beyond the divergence between continuity and rupture that marks, in a general way, the practices for envisioning the articulation of the new to the old.;When we compare Giovannoni's approach to the different views that have impacted modern urbanism, we find that his practices for using what already exists is the condition for the realization of urban heritage promises. Otherwise, the association of heritage conservation and urbanism culminates in the assimilation of urban heritage to the historical monument of architecture, and therefore leads to equating the urban project to the conservation project.;Key words: urbanism, urban heritage, conservation, urban morphology, Gustavo Giovannoni.