Leaning-Structure Statics—Flying Buttresses and Mayan Vault Ceilings

Abstract

Although entirely different in appearance, both cathedral flying buttresses and Mayan inverted-V-shaped vault ceilings are essentially leaning structures. The present study, illustrated by simple static structural analyses, demonstrates how slight but fundamental differences in the empirical developments of the common concept of a masonry leaning structure led to the construction of magnificent cathedrals in the case of flying buttresses, but a very limited architecture in the case of Mayan vault ceilings. The present study quantifies flying-buttress limit analyses, and extends one analysis to Mayan vault ceilings. Calculated quantitative relationships strongly suggest that the Mayan builders learned to position transverse wood struts reinforcing their vault ceilings and to use long ceiling stones primarily in a combined effort to ensure that the postconstruction structural behavior of the finished ceiling did not result in ceiling stones falling out, as well as to facilitate construction procedures. This is in contrast with previous studies that indicated that the practices of wood-strut reinforcing and long ceiling stones were adopted only to facilitate corbelling construction procedures.