Evaluation of traditional Iranian architectural arcs for optimum geometry design of single-layer diamatic lattice space domes

The selection of an appropriate geometric form is one of the critical factors in the design of space frame structures. Historically, the domes and arches in Iranian architectural monuments represent remarkable technical achievements, due to the geometric potential of their arched designs. However, previous studies on these structures have mainly concentrated on rehabilitation initiatives. This research, for the first time, seeks to use the formal features of arches and domes of traditional Iranian architecture to enhance contemporary structures made of modern materials. By incorporating the advantages of these historical arches into the design of lattice space domes, structural efficiency, and material utilization are anticipated to improve. To achieve this, the geometry of diamatic single-layer domes was designed based on seven commonly used arch types in traditional Iranian architecture. In addition, a diamatic dome is also modeled based on the spherical arch, which is commonly employed in space domes. The geometry of these space domes was first modeled in AutoCAD software. Then, the models were analyzed using the linear elastic method. Finally, the structural design of these space domes was performed using the LRFD method in SAP2000 software. The comparative analysis and design results demonstrate that arches such as Se-Bakhshi, Panj-O-Haft, Hasht-O-Panj, Se-Ghesmati, and Shakhbozi enable covering the same span with reduced material usage. Additionally, arches like Patopa and Shabdari offer the potential to construct taller domes with nearly equivalent material requirements.