استفاده از قالب‌گیری دوپوسته در مرمت و بازسازی سرستون‌های خانه صدقیانی تبریز جهت حفظ و ارتقاء کیفیت جزئیات فرمی نمونه اصلی

Special potentials of plaster causes that it becomes one of the mostly used materials in Iranian architecture in various historical periods. The potentials including low price than other materials, optimum resistance to environmental factors, fast hardening, ductility and good paintability are the main reasons for being using widely in Iranian architecture. These features results in using the plasters as the main material in the interior decoration of monuments in most historical periods. On the other hand, easy ductility and fast hardening cause that the Iranian architects use plaster in the various façade decorations of monuments. However, vulnerability of plaster to moisture and rapid climate changes in the mountainous regions reduces the life expectancy and becomes vulnerable in the exterior decorations of monuments. Hence, it is necessary that restoration and reconstruction of exterior facade adornments of historical monuments be established in the short-term periods. The Complex of Sadaghiani House of Tabriz is one of the monuments adapted on List of National Sites by No. 7498 on February 1, 2003. The house uses plaster in decoration of monument facade and capitals. This complex was built in mid of Qajar Era and a vast section of house had been demolished for reasons. The plaster capitals fully damaged. Following the retrofitting, the restoration of complex commenced in 2012 submitting to Tabriz Islamic Art University. After reconstruction of various sections of monument, few samples of residue capitals restored and reconstructed. Reconstructing the demolished capitals possesses complex form elements and details. It is costly and time-consuming. Hence, using alternative methods and the potential of techniques in relevant domains stands necessary. To duplicate the reconstructed capitals while maintaining the form features and structural details of samples, the method of hard-shell molding was utilized which is appropriate for molding those parts and artistic and industrial works that have complex form elements and negative spaces in their structure. This method entails a good robustness because of having a hard shell that usually uses FRP polymer matrix composites. In casting, assembly and installing mold on the determined site and using a flexible core, usually made of silicon resin, it reduces the number of mold Pieces and creates form details and negative spaces with an optimum quality. In this respect, one of the residue capitals with more complete form details was selected. Then, the stages of restoration implemented. Finally, the stages of molding and duplication of original sample carried out. Using the method in molding and reconstruction of demolished samples causes improving the quality, robustness, and expediting the process of restoration and reconstruction that has been reported briefly in the present manuscript.