La pietra artificiale tra storia e sperimentazione

In recent years the architectural culture has paid greater interest in the architecture of the twentieth century, triggering the need to preserve this heritage through systematic action for the protection of architectural production "modern". This spirit of protection has gained greater reflection about the construction techniques used and the choice of materials used, now totally derived from industrial and artifacts such as siding, artificial stone. The term artificial stone finds its origins in the second half of the nineteenth century, because in a French patent of 1875, with the title of "pierre factices", that is precisely artificial stone, is one of the first cases reported to recreate a material called pierre reconstitué (reconstituted stone), starting from a block of natural stone crumbled into small fragments and reassembled with cement binder. In fact in some cases we find similar artifacts Italian -based, however, hydraulic lime or air. From the Renaissance to the baroque architecture, where the component required for buildings highly decorative finishes of great plasticity and richness this practice found increasing application. Many recipes handed down from the sixteenth-century treatises four or show how it was refined and consolidated the preparation of artificial stone using binders aircraft initially and later also to those chalky. The treatise does not speak of artificial stone, a term that is used here, therefore, with the extension of the meaning, having preferably opt for the more traditional term of stucco, in its diversified forms. From the seventeenth century had a great spread to the processing of canary seed, which was replaced in part to imitate the faux marble and committed work, using materials of lower cost. The introduction of hydraulic limes and then change the composition of the cement stone materials, changing considerably the possibilities of expression, formal and, with the subsequent introduction of armor, also structural. And possible to precisely mimic the natural stone, creating products which are even more resistant and durable. The use of artificial stone cement in the first decades of application, roughly from the seventies of the nineteenth century, takes the uses already seen for artificial stones with binders aircraft: natural stone and artificial are juxtaposed and combined, preferring the first base areas and elements subject to greater wear and tear, but taking advantage of the plasticity of the second in most parts of the difficulty of execution, such as moldings and curved elements. In the late nineteenth and early twentieth century the decorative case studies and expression expands, in a period characterized by a sculptural and architectural eclecticism, where the ancient techniques are mixed with the new products that the market offers. The use of artificial stone in this period is intimately connected to the constructive elements, also of relevance static and constructive, with dimensions and conformation that gradually break away from the traditional models that had been imitated in stone above. Is thus establishing an architectural form highly dynamic, plastic and generous with sculptural effects, which is the first application in the eclectic décor, located completeness riding the decorative Art Nouveau movement, and later was consolidated with either a return to the eclectic historicism, and with the passage from Art Nouveau to Art Deco. The extreme search of the decoration, typical of the years between nineteenth and twentieth century, located in the cement binder plastic capacities and resistance to express themselves fully, giving rise to plastic and decorative devices of extreme complexity and articulation, definitely not achievable with traditional stone materials. The decorative richness of the architecture Liberty located perfection thanks to the original mixture of traditional materials such as brick, ceramics, glass, wrought iron, which is accompanied by just the use of concrete for the construction of the decorative artificial stone. The flower production and the subsequent return to the eclectic historicism, which characterize the first two decades of the twentieth century, are a prerequisite knowledge necessary for the study of artificial stone used in the architecture of the "fascist"