Recognition of Parameters and Applied Geometric Patterns in the Timurid Architecture (Case Study of Ghayyasi Kharjer School)

The great Khorasan and Transoxiana during the Timurid period have been a context for massive changes in the formation of Iranian schools. One of the architectural masterpieces of this period is the Ghiasiyah School (Ghiasiyah Madrasa) of Khargers, which was built by Qavameddin Shirazi in 846 AH . Nevertheless, what is considered in terms of architectural studies is the use of geometric patterns in the plan of this complex, the adherence to the human proportions and the balanced volume in the façade and the plan. The present paper aims at clarifying the proportions of the applied geometry and the application of module and high scale in the construction of the Ghiasiyah School. Therefore, it is attempted to answer the following questions: What were the pattern and geometric proportion used in the construction of the dome house, the plan and the façade of this building? Which Timurid systems of proportions have been applied by the architect to design this building? Relying on a descriptive-analytical approach and using library sources and field observation and recording, it can be argued that one of the distinctive features of the Timurid architecture is the greater use of geometry in architectural designs, whose representation can be seen in concavity and convexity (Nahaz and Nakhir) of the plan of Ghiasiyah School in a circular manner. Moreover, since the Timurid period was the flourishing age of mathematical calculations, and architects used various systems of proportions in constructing buildings, it can be stated that in the construction of the Ghiasiyah School a simple system of proportions such as (√2) and its derivatives have been taken into account in the dome house and the plan, and the derivatives of (√5) have been applied for the façade and the segment.