Abstract
In architecture a native of Iran is one of the principles of designing urban spaces people heir. Iranian architect has always been the human needs and demands into consideration. The architect of the past based on the desired climate space architecture in order to provide the human comfort design. Climatic conditions, along with other environmental factors, including the most important factors in the formation of the urban tissue. According to the characteristics of the architecture of the hot and dry climate of the burning sun of Iran and high thermal grade set, one of the last in the direction of the architect prolegomena ghosting in designed and produced Gzarha, awning. The awning are enable in the alley and Gzarha, which is part of Ford’s baths and climatic elements as well as the optimum biological requirements, in addition to making in retrofitting buildings of both sides of the Gzarha role. Unfortunately, nowadays in Iranian architecture, awning, to have been forgotten and the urban tissue of the awning or totally destroyed or have been to have been abandoned. With the recognition and evaluation of the architectural had knowledge of the geometry of the design knowledge can be structural elements of the ‘ climate-and once again, and also can be found in contemporary design and the urban tissue of the upcoming hot and dry climate of these special elements of the template. Between the geometry and the architecture of Yazd Fahadan quarter awnings body, and there is significant direct relationship. Based on the literature reviewed thus far, little research on the subject of the typology of Iranian awning and reviews of this climatic elements-from the perspective of structural knowledge of geometry.
Keywords: Indigenous Architecture of Iran, Geometry and Proportions, Consecutive Awning, the Yazd Fahadan Quarter.

Introduction
More research on the concept of the awning as the climatic element, check its stability in the amount of Gzarha and typology in the cities of Isfahan, Yazd, Kermanshah and because Shushtar. This document first geometric features of the architecture of the neighborhood, Yazd Fahadan awnings case is assessed. In the present study research methodology in terms of the objective applied-and in terms of the fundamental, method, method of inductive reasoning. The data field of a library, and on the left-hand tyranny. As well as the method of the analysis of qualitative data, quantitative methods-. After the library studies about the awning and its species, the hot and dry climate, awning, city of Yazd. Given that the neighborhood is one of the valuable historical neighborhoods Fahadan city of Yazd and had the original on the awning has chosen this neighborhood Neighborhood and 25 examples of this continuous awnings precious historic texture of the randomly selected, shooting data and to invoke the method of inductive analysis of the entire case apart. In this study, 256 Motalah sample random item selection and expressed. Between the geometry and the architecture of Yazd Fahadan quarter awnings body, and there is significant direct relationship. Based on the literature reviewed thus far, little research on the subject of the typology of Iranian awning and reviews of this climatic elements-from the perspective of structural knowledge of geometry.

Research Findings
This article focuses on the impact it has had on the geometry and shape of the neighborhood architectural desired awning case analysis. This research was completed in line with the previous research and reviews of historical proportions awning Fahadan quarter of Yazd. Based on the review conducted, became apparent between the geometry as a factor influencing the Fahadan quarter of Yazd awning architecture machines. The awning case study in terms of the geometry of the plan and the facade proportions and comply with the Iranian. The planning rectangular Fahadan quarter of Yazd awning is complete to the ratio of 1.73 and the ratio of that follow. This was evident in the analysis of the maximum number of the awning case reviews in terms of placement location in the middle of the pass. The largest number of covering arch with arch, and most of these Mazh awning in the direction North-South geographic have been drawn. As mentioned, an important element of the native architecture awning and climate are considered that Iran nowadays knowledge making it to oblivion. With this special climatic elements can be revived by the ancient native patterns as well as in the construction of the urban tissue and forming of new concepts that are of interest. In this study, the historical neighborhood of awning plan and valuable knowledge from the perspective of Yazd Sahadan geometry and rectangular proportions of Persia were analyzed. In future research can be found other than to work in Iran and other Persian architecture in the structure and architecture of the climatic elements-structural (awning) about the investigation. This test also can be used for other cities and places of historical texture of Yazd.

Conclusion
As mentioned, an important element of the native architecture awning and climate are considered that Iran nowadays knowledge making it to oblivion. With this special climatic elements can be revived by the ancient native patterns as well as in the construction of the urban tissue and forming of new concepts that are of interest. In this study, the historical neighborhood of awning plan and valuable knowledge from the perspective of Yazd Sahadan geometry and rectangular proportions of Persia were analyzed. In future research can be found other than to work in Iran and other Persian architecture in the structure and architecture of the climatic elements-structural (awning) about the investigation. This test also can be used for other cities and places of historical texture of Yazd.

Abstract  
Sustainable regeneration is an approach whose objective is to improve the economic, social and physical state of the historic environment and it is an approach which is familiar in the field of conservation and heritage protection. Documents and statements of this approach have been restored since the 1990s. Many studies have been done on this topic. Each of them proposes principles for the realization of regeneration but until now, none of them has provided comprehensive view in urban sustainable regeneration. This research aim is Explaining of the conceptual framework for sustainable regeneration of historical fabric. The Methodology of this research is functional on objective and content analysis in method. Analyses, comparison and summation are used in this paper. The conceptual framework is explained by analyses of documents, statements, charter and previous research. The zone of this research is all of the historical fabrics. In this research, regeneration of historical fabric is defined in 4 dimensions: economic, social, management and cultural. Property value, private investment and branding are Economic scales in Sustainable regeneration of historical fabric. Resource supply, Sustainable urban management, Citizen Participation and promoting the level of knowledge and awareness of society from historical fabrics are Sustainable regeneration in the field of management. Social status, social identity, Social capital and Social Security are social scales in Sustainable regeneration. Cultural scales in Sustainable regeneration are creative industries, cultural neighborhoods and Cultural events. So, this research seems necessary because of the attention to the dimensions and criteria of sustainable regeneration of historical fabrics. The aim of the present is to explain a conceptual framework for sustainable regeneration of historical fabric.
Keywords: Historical Fabric, Regeneration, Urban Sustainable Regeneration, Urban Regeneration Documents.

Introduction 
Historical fabrics face a variety of problems today, such as Exiting residents from area, Existence. Low-income people in it, and the imposition of high costs to conservation these areas. Experience shows that applying a single-dimensional model in the urban system in which historical fabrics is located, generally leads to serious problems. Therefore, when making a model, it is vitally important to take various aspects of the issue into consideration including economic, social, cultural, demographic, and management indexes. Accordingly, one of the most recent approaches dealing with historical fabrics in urban planning, is urban regeneration approach. This approach was originally emerged from the principles raised in sustainable development and from the growing importance of the participation of relevant groups in the process of urban planning. One of the salient features of urban regeneration approach is that it simultaneously takes into consideration social, economic, cultural and management indexes in historical fabrics. In similar studies previously done by other researchers, certain factors were suggested to realize sustainable regeneration. However, no integrated model has been so far suggested to comprehensive attention of historical fabrics. In this research, in order to provide a model for the dimension of social sustainability. So, this research seems necessary because of the attention to the dimensions and criteria of sustainable regeneration of historical fabrics. The aim of the present is to explain a conceptual framework for sustainable regeneration of historical fabric.
 
Text of paper
Regeneration approach focuses on improving economic, social, and environmental conditions of the city. It covers a wide range of activities which makes deserted regions, worn-out buildings and those being reconstructed, habitable again. Regeneration, broadly speaking, is meant to improve the general conditions of city and citizens (Hull, 2000: 77). Different definitions of sustainable regeneration indicate that this approach focuses on improving economic, social, cultural, environmental and physical conditions.
Economic in historical fabric’s regeneration: To English Heritage (2008), the main purpose of regeneration historical fabrics is to make the productivity of the place. It provides return of fund for owners or developers. So, it provides income for conservation and preservation of historical buildings and fabrics. 
Management in historical fabric’s regeneration: The preservation of historical contexts does not make without the presence of the people. So, attracting and creating the necessary context for people’s presence requires management tools.
Social in historical fabric’s regeneration:  To Assefa and Frostell (2007), although all principles of sustainable development are involved in regeneration, it is the recently-poised issue of “social sustainability” which is the main topic in sustainable places. While it has been suggested that the final goal of development is social sustainability, economic and environmental sustainability are also two pivotal tools by which sustainable development is reached.
Culture in historical fabric’s regeneration: To pour Ahmad et al (2010), the most important aspects of this approach are the attention to the role of culture, the use of historical and cultural values as resources for development and the leisure time of the people.
Regarding the dimensions of the historical fabrics’ regeneration approach, this study categorized the regeneration variables into four economic, managerial, social and cultural dimensions. To this end, major document and charters released since 1990s, when the idea of urban regeneration started to emerge, and studies related to this subject were examined.

Conclusion
In this study, the criteria for sustainable regeneration of historical fabric were identified with reference to documents, statements and charters and previous researches. The results of the study have introduced criteria in four economic, managerial, social and cultural dimensions for sustainable regeneration of historical fabric. Economic value, private investment, and branding are criteria of the economic dimension of sustainable regeneration of the historical fabric. Criteria for management of historical fabric have been introduced such as resource preparation, sustainable urban management, citizen participation, and the development of knowledge and awareness. Social capital, social security, social status, and social identity were defined as dimensions of social dimension in regeneration. Creative industries, cultural neighborhoods and cultural events are criteria for cultural regeneration of historical fabrics. The table below shows the sustainable regeneration criteria of historical fabrics.

Abstract
Interventions related to the use of historic buildings, in addition of rehabilitation, are known in other different terms including revitalization, empowerment, adaptive reuse, etc. However, so far, ther is no research has been done on these terms of interventions by Iranian academics, and this multiplicity of intervention terms and, at the same time, lack of clarity in the concepts, differences between them and their international equivalent terms, has caused confusion among the researchers. The purpose of this paper is to analyze these concepts and other concepts related to reuse historic assets and to determine their relation to each other. In this regard, while studying prerequisites and requirements of functional interventions, different approaches to the subject at the international and national levels are surveyed and the different types of functional interventions in these buildings are analyzed and compared. In order to do the abovementioned, the analytical-descriptive method was used in the first part. In the next section of the article, a comparative study based on logical reasoning has been used to examine the relationship between different reuse interventions. From the findings of this study, it can be noted that the major differences between the various terms in the scope of reuse interventions are due to two major issues of “different word formation in translation” and “belonging to different time and place coordinates”, while they have common underlying concepts and all emphasize on the “role of existence a use in a building in its sustainable conservation”, “the necessity of adapting new uses with cultural significance, values and authenticity of the historic monuments” and “adequately meet to the needs of contemporary life in these buildings.
Keywords: Compatible, Resuscitation, Rehabilitation, Empowerment, Compatible Reuse.

Introduction
So far, few studies have been done on this topic in domestic research in Iran, so that there is no consensus in many of issues in this field especially on terms. Thus, we certainly need to do extensive and in-depth research in this regard, but its prerequisite is to study on the basic concepts of the subject; Knowing that what issues have been considered in the interventions in international literature?
The main purpose of this article is to explain the concepts of this field, in this regard, addressing the reasons and requirements of functional interventions by looking at international documents and charters is on the agenda; Then the different approaches in this field in international and domestic literature are explained and finally the main field of the article is to identify the types of functional interventions through comparative comparison.
Addressing this issue, in addition to the fact that the existence of function in a building ensures the survival and conservation of the building, is also important in terms of sustainable development and environmental issues. Also, considering that while functional interventions can provide protection for the historic building, it may also cause irreversible damage to them, it is vital to determine the necessities and sensitivities for the conservation of historic buildings in this process.
The present article specifically seeks to answer the questions about concepts of different types of functional interventions, their relationship between each other and their different uses. Also, it is going to clarify what is the relationship between the domestic terms of interventions and their international equivalents?
The present article is a basic research that seeks to expand the knowledge on the subject of “rehabilitation” by explaining and analyzing some of the concepts, resulting from library studies. In this regard, first the different aspects of functional interventions have been explained by “analytical-descriptive” method and then by using “comparative comparison” method, the different types of domestic and international definitions provided for functional interventions have been defined and compared.

Conclusion
The following results are obtained from reviewing and comparing the definitions provided for functional interventions and based on studies:
Despite the fact that in most translated literature, the term “Rehabilitation” is equated with “Tavanbakhshi” or “tavanmandsazi”, but considering the common use of the word “Ehya” in Iranian academic and professional circles for this type of intervention, it should be accepted that the term “Ehya” is the proper translation for this kind of intervention; but it seems that because “Ehya” has been used for the urban intervention of “revitalization” at the same time in many academic papers, it made some scholars to find out a new equivalent for the “rehabilitation”. Overall, it can be said that although in recent years translating the term “rehabilitation” into different equivalents has caused confusion and has produced different literature; but comparing the definitions reveals that all these terms are different equivalents for the term “rehabilitation”.
Regarding the relationship of “rehabilitation” and “adaptive reuse”, some such as “Deathridge” (2012: 5) argue that in “adaptive reuse” the use of the buildings definitely change to new uses, while a “building may be rehabilitated to its former purpose or adapted to a new use”, therefore “all adaptive reuse is rehabilitation, but not all rehabilitation is adaptive reuse.” However, not all researchers believe this, and a comparison of the definitions provided for these terms, which despite all their differences, all have the same concepts which emphasizes “adaptation of buildings to appropriate and compatible use”, shows that these measures are no different but they simply belong to different times and places.
Regarding other relevant interventions, it can be said that changing the term does not necessarily change the action; as “Douglas” (2006: 1) believed “There are many other different terms that are used to describe interventions to a building that go beyond maintenance. Words such as ‘refurbishment’ or ‘rehabilitation’ and ‘renovation’ or ‘restoration’ are occasionally taken as being synonymous with one another, even by some in the construction industry.” Also in this case “Markus” (1979) noted that “in the world of building the terms “rehabilitation”, “conversion”, “remodelling”, “restoration”, “reinstatement” and so forth are unhappily confused.” (ibid) In addition, Wilkinson (2014: 4) confirms this claim and adds terms such as ‘retrofitting’, ‘modernisation’, ‘re-lifing’, and ‘recycling’ to the abovementioned.
Some of these words in different places are considered equivalent to a specific concept due to their common use; “Refurbishment”, for example, has gained widespread use in the UK as the most popular term to describe a wide range of adaptation work; however in the USA “Remodelling” is commonly employed as an all-encompassing expression for these works. Also “occasionally some ‘building adaptation’ terms are used together. Certain construction companies, for example, advertise their services as ‘specializing in renovating and refurbishing old homes’. Other contractors use the expression ‘extensions and renovations’.” (Douglas, 2006: 1-2).
Overall, as mentioned, there is several terms for functional interventions in historic assets in Iran, which although the multiplicity of these terms has confused researchers, but further study of their meanings shows that the focus of all these measures is on adapting the buildings to the appropriate and compatible use regarding to cultural significance, authenticity and values of the building; and the formation of different terms has been more due to the two issues of “different word choice in translation” and “belonging to different spatial and temporal situations”. In this regard, it can be said that in domestic literature in Iran, “Ehya”, which is equivalent to “Rehabilitation”, is the main keyword on which the specialized literature is based, but “adaptive reuse” is also a newer term which originates from the USA and Canada and gradually has spread around the world and today is one of the main keywords in this field. “Adaptation” is also a term which includes all interventions related to the functional interventions of historic buildings. In general, it seems that the agreement of the scientific and executive community of the country on the term “Ehya” and the formation of institutions and documents on the basis of this term, requires that focusing on this concept, handle the disagreements to be able to expand its aspects and essentials in the future researches.

Abstract
The landscape formed by the holy places of the pilgrimage cities is considered a central element in recognizing their physical and semantic indicators. These landscapes unite their affiliated religious rituals and ceremonies in a useful framework while developing an integrated whole in temporal and spatial aspects. The spirit of these landscapes is the human soul. Therefore, what causes disruption and chaos in this relationship disrupts the authenticity of these holy places and the integration of their immediate fabrics and will have undeniable negative effects on the pilgrimage. Since the residents have always considered these spaces, pilgrims, and even tourists, their written and illustrated documents can be examined to represent the subjective and objective aspects of the mentioned landscapes. In this regard, by raising the question, what aspects have the physical and semantic structure of the stated landscapes included throughout the past ages? The current research aimed to find the apparent and latent aspects of this subject to represent the central features of the landscape of the pilgrimage cities of Shiite religion and the role of their holy shrines. To this end, the derivation approach was selected based on inferential-historical and thematic analysis methods, and the texts and images of 29 travelogues reported in the interval of 6th to 14th AH were studied. The findings indicate that as symbols and indications of the pilgrimage city and individual and unique in their surrounding area while having an integrated cohesion in the natural context of the city, the stated places arranged the landscape in the form of a united complex, including all the relations, events, and its related local customs and rituals. The result shows that the sacred landscape of these places was a semantic network and a series of tangible and intangible values and elements requiring increasing attention to conserve their visual sanctity zone and review the current plans and measures. 
Keywords: Sacred Place, Ritual Landscape, Pilgrimage Landscape, Sacred Landscape, Visual Sanctity Zone.

Introduction
Religious landscapes reflect ritual beliefs and thoughts, and the sacred landscape of a pilgrimage city is considered its inseparable element. The sacred places create privileging landscapes in the urban landscape and, as a known indication, contribute to determining the cultural changes of their related historical-geographical fabrics. However, nowadays, claiming the uniqueness of these places due to having prominent spiritual values and deep religious roots in the related culture and religion, the visual sanctity zone of these cultural properties has faced numerous irregularities and disorders. The conservation of the visual sanctity and the landscapes formed by these places will significantly affect the organization of the mental image of their audiences to recognize them besides its significant role in protecting the authenticity and identity of its affiliated cities. Thus, according to the stated necessity, by raising the question, what aspects have the stated landscapes included in the interval of 6th AH to the early 14th AH? the current research aims to represent the central and influential indicators in the structure of the scared landscapes of the Shiite pilgrimage cities through which it can obtain rethinking and developing the practical principles in the plans.
It is noteworthy that the main focus of any previous research was not on the sacred landscape of the famous pilgrimage cities of Shiite religion, and the current study analyzed the narrations of the travelogues from a new perspective. Since the current research had a qualitative-interpretive paradigm based on the analytical induction and required analyzing the text and illustrated data, the applied method was the historical-inferential and thematic analysis method.

Discussion
A landscape can include the cultural history of a place with legibility capability and message, and since the effect of the belief insights and religious beliefs is obvious thereon, it is considered a religious landscape. Primarily, this landscape includes all the cultural and social activities in its related religious area, and then, it is considered an area of the civil and structural territory of a city. Beliefs related to the spaces formed by the previous two areas, the scale and how it is related to a particular place, a region, or the integrity of a city according to the worldview system that governs it, are manifested and in concepts and titles such as “ritual landscape”, The “pilgrimage landscape” and the “sacred landscape.”
A sacred landscape of a pilgrimage city cannot be perceived correctly, disregarding how the sacred places play a role in its prospect. In other words, the indications of the spatial separation between the holy shrines and their surrounding and external spaces are considered the elements of the sacred landscape. For instance, in Khorasan Travelogue, while mentioning a place in the suburb of Mashhad called “Tappeh Salam”, Houtum-Schindler states that “Mashhad city with its sacred dome of Imam can be seen from this hill”.
Thus, the observation, imagination, and even thinking about how these landscapes were created varies based on people’s worldviews.
Considering the abovementioned and based on the narrations recorded by the travelers, it can be deduced that the sacred landscape was one of the central bases of travel writers’ subjective structure map so that it began from the historical core of the city, which included the shrine and its surrounding areas and extended to the suburb. Their first descriptions before reaching the entrance of the city were the description and explanation of a landscape that indicated the religious and pilgrimage identity of that city, and can be divided into two main groups as follows:
1. Representing the visible and tangible structures of the holy shrines and their immediate surroundings,
2. Expressing the intangible and latent aspects of their affiliated landscapes. 
Others indicate the importance of a sacred place as a focal landmark and valuable element of the pilgrimage city that all the visual attention led to that. The integration with the natural elements is one of the cases that extended to these places’ core and internal zones.
The extracted propositions indicate that the interaction of the religious values, natural context, and the residential fabric neighboring the holy shrines with a network of the cultural systems, such as pilgrimage behaviors, local beliefs, and customs, human interactions, Etc., formed an integrated network of communications besides the sacred place as the central core the results of which was the formation of the integrated sacred landscape in the physical structure of the pilgrimage city.

Conclusion
The obtained result shows that the sacred landscapes of the stated holy places included a perfect and homogenous complex in the aesthetics background role and displayed a multifaceted manifestation for the viewers’ thought and perceptions like a communicative-social system. In other words, these scenes are a manifestation of the coexistence and synonymy of structural-semantic elements in the observer’s mind so that the hole formed in their dependent context represents the importance of the quiddity of the holy shrines.
Therefore, the values of the sacred landscape and its related meaning were entirely dependent on the cultural aspect of a context, which has been integrated with traditions, rituals, and beliefs over time. It is related to a relationship between the human, sacred place, and immediate environment. These landscapes were related to the sense of a metaphysical presence and lived through the religious symbols and rituals, such as pilgrimage, because the feelings experienced by the pilgrims and viewers, such as travel writers in the current research, were under the influence of a set of features of the sacred shrine. The high visual quality that integrated the sense of place and sense of sanctity zone surprisingly in the audience is proved by the high visual quality that integrated the sense of place and sense of sanctity zone. Therefore, it can be concluded that these landscapes indicate the attributes, context, and background of the holy shrines. Thus, one cannot disregard the two-way and inseparable relationship between two tangible and intangible cases linked with their related landscapes in today’s development plans of these places.  

Abstract
Khuzestan, a primary center of mudbrick and fired-brick architecture in ancient Iran, witnessed the evolution of vaulted construction from the Elamite to the Late Sasanian periods. Among these, arched vaults served not only as structural elements but also as a demonstration of systematic engineering practices tailored to the region’s warm and semi-humid climate. Despite the abundance of surviving monuments, no comprehensive study has analyzed their technical and structural features to uncover the underlying stability principles. This study aims to examine the structural performance and recurring patterns of stability in arched vaults of Khuzestan. Field surveys, documentation of accessible structures, analysis of 111 identified vaulted buildings, and detailed examination of 21 selected representative examples were conducted. The study focused on the interaction of materials, geometric proportions, construction technology, and human craftsmanship in achieving long-term stability. Results indicate that vault stability depended on: 1) the type and geometry of bricks, consistent mortar thickness, and interlocking strategies; 2) diverse construction techniques, including corbeling, radial arrangements, and combination methods; 3) geometric proportions such as span, rise, and vault thickness; 4) adaptation to climatic conditions; and 5) the skill and experience of the builders. This research highlights the presence of a systematic engineering logic in pre-Islamic vault construction and provides a framework for restoration, conservation, and potential adaptation in contemporary architectural practice. The findings demonstrate that these vaults were not merely empirical or accidental in design but reflect deliberate, replicable, and coherent structural strategies.
Keywords: Structural Stability, Vaulted Architecture, Arched Vaults, Pre-Islamic Iran, Khuzestan.

Introduction
Khuzestan has historically played a pivotal role in the development of vaulted architecture within ancient Iranian civilizations. Vaults represent one of the most sophisticated elements of traditional construction, combining technical mastery, material understanding, and adaptation to environmental conditions. From the Elamite through Late Sasanian periods, vaulted buildings in Khuzestan reveal an evolution in construction techniques, reflecting the accumulation of knowledge and local innovation. Arched vaults, in particular, served as primary structural and functional components in ritual, funerary, administrative, and sometimes military architecture.
The study of these vaults provides insight into the strategies employed by ancient builders to achieve stability over centuries. Stability in traditional architecture encompasses not only physical durability but also cultural, climatic, and technical resilience. Builders utilized local materials, precise geometric proportions, and structured load distribution to respond to environmental and functional challenges. Despite extensive archaeological documentation, there has been limited focus on the technical principles underpinning vault stability, particularly in arched vaults.
This research addresses this gap by systematically analyzing recurring structural features, material properties, construction technology, and geometric patterns that contributed to vault durability. The study examines both historical continuity and the adaptation of techniques over time, demonstrating that pre-Islamic vaulting practices in Khuzestan were informed by deliberate engineering logic rather than trial-and-error. Understanding these principles is critical for bridging knowledge gaps in architectural conservation, informing restoration efforts, and inspiring contemporary applications of traditional construction methods.

Discussion 
Analysis of arched vaults in Khuzestan indicates that their long-term stability resulted from a combination of material selection, construction technology, geometric design, and human skill. Key aspects include:
Materials and Mortar: Builders employed trapezoidal, square, and rectangular bricks, wider and thicker at structural bases to distribute loads effectively. Mortars, including clay, gypsum, and bitumen, were chosen according to moisture conditions, ensuring cohesion and stability.
Construction Techniques: Techniques included inclined corbeling, radial arrangements, and hybrid approaches. Temporary wooden or reed supports facilitated precise execution, while multi-layer vaults with controlled thickness enhanced overall strength. Adjacent vaults were often coordinated to reduce lateral stresses.
Geometric Proportions: Ratios between span, rise, and thickness were carefully maintained across periods. Numerical proportional systems guided vault dimensions, while precise interlocking of bricks ensured efficient load transfer.
Human Skill: Mastery in aligning bricks, controlling mortar thickness, integrating vaults with walls, and designing stress-relief features such as recesses and buttresses reflected high craftsmanship.
The historical evolution from Elamite to Sasanian periods shows gradual refinement. Early Elamite vaults utilized simple rectangular cross-sections and limited brick types, while Late Sasanian vaults displayed sophisticated high-rise arches, modular brick use, and multi-layer arrangements. These developments indicate a cumulative knowledge system that informed construction practices and responded to functional and climatic challenges.
The study highlights that stability was never accidental; rather, it emerged from repeated, rationalized engineering practices. Such findings provide an empirical basis for restoration and reconstruction, enabling the preservation of architectural integrity and informing contemporary design strategies that draw upon historical methods.

Conclusion 
This research demonstrates that arched vaults in Khuzestan were underpinned by systematic engineering principles rather than empirical trial-and-error. Stability resulted from the integrated interaction of materials, construction technology, geometric design, environmental adaptation, and craftsmanship. The study identifies: 
- Strategic use of brick types and mortar selection to optimize structural cohesion.
- Refined construction techniques, including corbeling, radial arrangements, multi-layer vaulting, and controlled thickness.
- Geometric proportionality ensuring balanced distribution of forces.
- Adaptation to climate and environmental constraints.
- High-level craftsmanship in aligning elements and controlling structural behavior.
Historical analysis reveals a continuous technological development, culminating in Late Sasanian vaults that exemplify peak structural refinement. Documenting these features provides a foundation for preservation, restoration, and potential adaptation in modern architectural practice. Future studies may compare these vaults with contemporary structures in neighboring regions or explore the influence on early Islamic architecture in southwestern Iran.
The study confirms that pre-Islamic vault construction in Khuzestan represents a coherent, replicable, and sophisticated engineering tradition, offering valuable lessons for both conservation and contemporary design.