ABSTRACT
Gothic architecture, while it looks frail and unstable, has survived for centuries. Some 17th- and 18th-century architects and engineers praised its robustness, but gave no explanation for it. Only Viollet-le-Duc tried to resolve this contradiction. For decades he inspected, surveyed and studied countless Gothic buildings and observed that the stone skeleton, this charpente de pierre, was capable of suffering deformations and maintaining equilibrium without collapsing. Viollet-le-Duc called this property élasticité: Gothic construction in stone was “elastic”, flexible. Viollet-le-Duc’s theory was accepted by the next two generations. By the 1920s, several authors strongly criticized its vagueness and contradictions. But it turns out that Viollet-le-Duc’s intuition was right. The limit analysis of masonry, developed by Professor Heyman in the 1960s, explains the robustness of the Gothic structure, which can crack and deform safely, finding always a state of stable, safe equilibrium.
