Catalan Vault

The Catalan vaulting technique in particular made it possible to build spectacular structures, with designs by, for example, Antoni Gaudí or Rafael Guastavino, and was employed in a wide range of applications during the first half of the twentieth century, at which time it was replaced by new methods of construction and modern building materials such as concrete and steel.
http://detail-online.com/inspiration/technology-the-catalan-vault-%E2%80%93-a-historical-%C2%ADstructural-principle-with-a-bright-future-106565.html