Comparative study of physical and functional structure in Tabriz Saheb-Abad square and Isfahan Naghsh-e-Jahan square in hictorical periods

Paying attention to the importance of square can be seen in architecture and organization of physical space of Iranian cities in the past, before Islam and also after that in Islamic urbanization. Saheb-Abad square of Tabriz, Shah square og Qazvin and Naghsh_e_Jahan square of Isfahan are samples of past squares which present power of governments and subtlety of governmental kings that build them. Based on recent researches theories,  Naghsh_e_Jahan square of Isfahan was built (at the age of first Abbas of Safavi kings, i.e. (998-1038 AH.), according to Saheb-Abad square of Tabriz which is built before Safavieh era and during Aq-Qounlou era (870-896 AH) and it was influenced by architecture of Saheb-Abad square of Tabriz and because remaining physical structure of Saheb-Abad complex of Tabriz is mainly related to buildings that were made during age of Qajar kings on the buildings of governmental complex of previous eras, acceptance of this assumption resulted in proposing renewing projects of Saheb-Abad with full imitation of now a days physical structure of Naghsh-e-Jahan which is exists now and without paying attention to original structure of Saheb-Abad and when it came to existence and when it was on its tip-top, in the past. Then in this research, based on both Saheb-Abad and Naghsh-e-Jahan research which are studied based on content analyzes historical-comparative guideline appearance, and step by step transformation, in the past. Finally, according to comparative study of mapped schema, recognize of similarities and differences of these two complex were found, both physically and functionally, in four time periods. The results indicate that there are the most common similarities in the history before the construction of the two square and the most differentials in their current state. In the course of historical evolution, two square are very similar in terms of functional and the types of uses than the physical dimensions. Also, the greatest point of physical distinction is the uncertainties of the Sahib Abad field, which has led to many changes and further decline of this collection up to the present.the complete acceptance of this assumption which Naghsh-e-Jahan of Isfahan is a similarity of Saheb Abad complexes of Tabriz, both functionally and physically, cannot be correct and it can be said that the overall structure of the Saheb Abad complex in the peak of its glory (the period of Shah Tahmasb Safavid) could have been the pattern of an urban space with various governmental-political, socio-cultural, religious, and sporting activities for the construction of the Naghsh-e-Jahan of Isfahan.