Expressing the application of proportions in Performance the yard of traditional homes In Behbahan(Qajar and First Pahlavi periods)

The use of proportions has always been considered in traditional Iranian architecture, and especially after Islam, because of the creation of an architecture that is far from Individual Interests and the impact that has on the quality of  building conceptual understanding. The purpose of the present study is to examine the proportions in the courtyards of the historical houses of Behbahan city and to express their characteristics in order to provide a true picture of the proportions governing them and to provide a starting point for future research in the field of proportions. According to the studies that have been done so far, the architecture of major buildings and even the architecture of famous cities such as Kashan, Yazd, Isfahan and Shiraz have been used in some way, However, there has been no research on the use of proportions in the traditional architecture of smaller cities. However, examining the suitability of buildings in each area over different time periods can help to complement the architectural information of traditional buildings. And finally, by completing the information, check that the proportions used are the same or different in different regions. And basically what are the reasons of their differences and similarities. That represents a new window into Iranian architecture. The first step in achieving this is to examine the proportions in different areas. The city of Behbahan is no exception, due to its several thousand years history and its role in all historical periods. In addition, Behbahan was once a major commercial city and dock (base) of Khuzestan, Pars and port cities. And its historical texture has more than 40 neighborhoods, with many valuable buildings in terms of architecture. However, less research has been conducted about the architecture and features of traditional houses in Behbahan. And, except in books such as the Book of "Identity of Behbahan", and some travel logs and memories such as " Travelogue of  south iran ", it has not been done in detail as a comprehensive study. Hence the choice for this research. But due to the wars and wreaks that took place in the Khuzestan region, and also the warm weather conditions of the region, and also the lack of attention of organizations, landowners, unfortunately, today few of these historic houses remain, that  most of which belong to The Qajar and the first Pahlavi era. It is necessary to check the proportion in different buildings But since the house is considered as an essential part of any period building and the courtyard has always played a central role in the structure of traditional homes, This research tries to study the proportions in the courtyard of Behbahan houses. In order to answer the main question of this research, "Which of the proportions has been used in the traditional architecture of Iran in the courtyards of Behbahan houses?" To answer the above question, a descriptive - analytic method has been used in this research. Today there are many houses in the historical context of Behbahan that Mostly remained from the Qajar and Pahlavi periods. There were 31 homes available for researchers based on documents available,that 10 were selected.On the condition that in choice of samples for each period, criteria such as appropriate historical value, specific construction period, healthy architectural framework, and no interference, have been taken into consideration. Of these, 8 are listed on the National Heritage List. Firstly, using library studies tools, different types of architectural ratios and architecture of Behbahan houses are studied. Then, by gathering documents and using field studies and the direct presence of researchers in the houses, their general characteristics, including the period of construction, the neighborhood and the components of the houses, were extracted, Finally, the dimensions required for analysis were extracted from maps using AutoCAD software and based on the graphical scale size of the maps. In the last step, using descriptive-analytical method by Excel software and in some cases by geometric analysis, the data is analyzed based on architectural proportions. The results show that, Among the existing proportions used in the Behbahanchr('39')s courtyards in both Qajar and Pahlavi periods, most of them follow the Iranian gold and square geometry, and the 1.618 golden ratios are less of a concern for architects. In general, the use of √2 and √1.25 ratios is more commonly used in construction and measurement because of its proximity to square form and its simplicity and speed. Some homes may also had been fitted to a part of facade that is more important than other parts or has symmetry such as a porch or three-door and five-door rooms, This confirms the importance and application of proportions in the main spaces of traditional homes. In addition in some aspects, the combination of two proportions is used side by side.