Cementless Compositions for the Restoration of White Stone Based on Lime Binder and Silicon Dioxide

The condition of architectural monuments is directly influenced by various factors, such as anthropogenic, natural, and technological, leading to the degradation of both structures and construction materials, ultimately resulting in irreversible damage. These factors diminish the quality of construction materials, contributing to alterations and the destruction of the appearance and structure of white stone. The primary objective of this research is to develop cement-free compositions for restoring ancient masonry materials. Tests were conducted at the BM Department of VlSU using modern equipment. New material compositions for restoration have been devised, combining lime and silicon dioxide with chemical additives to enhance adhesive and strength properties. Adhesive strength increases by 1.5 times with the addition of white soot (silicon dioxide). Moreover, the incorporation of silicon dioxide positively impacts compressive strength (from 10.6 to 15.6 MPa), surpassing the strength of composites without white soot by 1.5 times. XRD confirms the developed composite's similar phase composition to white stone, supported by optical microscopy and SEM results. Restoration composites based on these compositions exhibit homogeneous structures compatible with white stone and demonstrate high adhesion levels. These results make the proposed compositions promising for white stone restoration, ensuring structural and chemical compatibility with the restored surface.