The erosion of adobe heritage under the influence of natural factors, especially rainfall and humidity, is one of the most important challenges in the conservation of this heritage today. Alongside traditional options for the protection of adobe heritage, such as the use of straw plaster, in recent years, various chemical products have been marketed for the protection of building materials and components, especially against the threat of moisture, and consequently, serious tendencies have been expressed in the field of evaluating these materials in the field of conservation and restoration. Therefore, the scientific evaluation of the properties of these materials seems necessary for their judicious use. Since many of the chemical materials available in the market are mainly designed for the protection of stone and brick, it seemed necessary to conduct this study in order to protect adobe materials and optimize the penetration of these materials into the adobe texture. In this research, considering the need to increase the resistance of adobes against moisture, the hydrophobic properties of four different commercial products with the names of Stain Repellent AKEMI, SRP130, PTS+ and Long Life, were evaluated and compared with each other on the structure
of adobes. The results of the research showed that although all the commercial materials studied provide the possibility of significantly increasing the resistance of adobe against moisture, the Long-Life material has a higher ability to penetrate and hydrophobize adobes compared to other chemical products. This issue can significantly increase the surface resistance of the adobe against both long-term contact with moisture and against mechanical erosion factors. The results of this research can be used as a basis for future studies in the direction of localizing chemical materials for the protection of adobe works and optimizing their application in the conservation and restoration of adobe historical buildings.
The restoration of historical monuments and the preservation of the culture of each country becomes a national duty. Considering masonry materials of traditional Iranian architecture include clay and adobe with low strength, methods such as Fiber-reinforced polymer (FRP), waterproofed mud, and the addition of natural materials like zeolite are proposed for restoration and strengthening. The zeolite used has a low specific surface area, which has increased from 23.92 to 45.16 m2/g through plasma modification, Additionally, it has modified the morphology to a fiber-like shape with no essential differences in the primary structure. Given these changes, it is expected that there will be an increase in strength and a minimum of 1.5 times lower water absorption in zeolite-based mortars.
The remains consisting of adobe and mud structures extend over an area of 180 hectares, located 3 kilometers south of the current city of "Esfarayen" in North Khorasan, Iran. Archaeological studies of the last two decades, in addition to various cultural findings, have also revealed various architectural structures, which include the historical site of Belqis Esfarayen along with the remains of Narin qale (Military Castle). Given the frequent erosion of adobe due to moisture from limited rainfall in the region during conservation interventions, addressing soil quality characteristics and identifying crystalline structures in erosion processes was the goal of this research. Laboratory studies conducted through physical and chemical tests demonstrated that soil quality is the main cause of clay erosion. This is attributed to a combination of factors: the lack of clay and the high percentage of silica on one hand, and the presence of muscovite and secondary calcite crystal structures on one hand.
The Qariha Historical House is a surviving structure from the Mozaffari era in the city of Yazd, reflecting transformations across various historical periods. This building, along with other structures from the same era, holds significant value due to its association with the golden age of Ilkhanid art and architecture, making it a compelling subject for multidisciplinary studies within the field of conservation science. To mitigate the deterioration of its structural elements and address existing damage, a series of conservation and restoration interventions have been implemented. These measures include localized foundation reinforcement, restoration and reconstruction of portals, repair and realignment of damaged arches, stabilization of wall layers and coatings, and the clarification of architectural decorative elements. This article aims to provide a comprehensive account of the conservation and restoration efforts undertaken for this historical building.
