Realization of historical Persian ornamental and geometric patterns as architectural components in innovative reciprocal frame barrel vaults

Barrel vaults are one of the most widely used forms in Persian architecture. While they are mainly built with heavy and compressive materials such as brick, today’s advances in construction techniques has led the architectural industry to utilize lightweight structural systems including reciprocal frame structures (RF). The purpose of this paper is to generate a barrel vault form using RFs through a revival of historical Persian ornamental and geometric patterns known as girih. This research was carried out in three phases. After extracting the essential criteria necessary to produce reciprocal configuration, four geometric girih that were compatible with those criteria were selected. The selected patterns were then modified to localize their reciprocal configurations following the Persian ornamental and geometric patterns. A structural analysis was performed using the Karamba Plugin in order to make a structural comparison between a barrel vault constructed with RFs and one made with bricks. The results showed that the use of RFs can significantly reduce the structural weight while using a minimum of material in covering the specified span. In addition, it was concluded that the vault with Hasht-e-moraba and Chahar-lenge ghenas patterns behaved in a more optimal way for the transmission of axial forces with less displacement and deformation.