Experimental assessment of existing ideas on brick vaults by slices building process

Abstract

This paper deals with brick vaults by slices, that is, those built with no formwork, where the brick is vertical or inclined, held by the mortar adherence, and the courses form thin arches, which will finally show only their headers or stretchers on the intrados. Those vaults have been built in many different cultures and periods, in particular in Byzantium, in large areas in the Iberian Peninsula, especially in the Extremadura region and, more recently, in Mexico. The paper focuses on the material aspects of brick-and-mortar placement, the form of the slices, and the sequence of operations in the construction process. Original written sources will be critically analyzed, taking into account actual construction practice carried out by Mexican and Extremaduran bricklayers and physical models specifically prepared for this paper. This study reviews ideas of Spanish authors from the nineteenth century and statements of twenty-first century bricklayers, about the way in which the bricks should be placed, the mix ratio and use of mortar, the shape of the courses and the procedures that control the shape of the vault. Both historical sources and statements from practicing bricklayers, together with actual experimentation of the operating procedures, as well as the use of models, reinforce or deny traditional ideas.