EFFECTS OF SALINIZATION IN THE ARAL SEA BASIN (UZBEKISTAN) ON THE STRUCTURAL INTEGRITY OF CERAMIC WALL MATERIALS

Abstract

Salinization associated with the desiccation of the Aral Sea has become one of the most critical environmental factors affecting the durability of construction materials in Central Asia. Although the deterioration of concrete and natural stone under saline environments has been extensively investigated, quantitative information regarding the long-term performance of ceramic wall materials remains limited. This study evaluates the influence of saline exposure on the physical and mechanical properties of fired ceramic wall materials through a combination of field observations and laboratory simulations. Ceramic brick specimens collected from highly saline regions of Uzbekistan were compared with laboratory-prepared specimens subjected to repeated wetting–drying cycles in sodium chloride (NaCl) and sodium sulfate (Na₂SO₄) solutions. Changes in compressive strength, water absorption, density, and visible deterioration were evaluated using internationally accepted testing procedures. The results demonstrate that sulfate-bearing environments produced substantially greater deterioration than chloride environments owing to higher crystallization pressure during repeated hydration–dehydration cycles. Progressive salt crystallization promoted pore enlargement, surface efflorescence, cracking, and reduction of mechanical strength. Field observations confirmed similar deterioration patterns in ceramic masonry exposed to long-term saline conditions in the Aral Sea Basin. The combined field and laboratory investigation improves the understanding of salt-weathering mechanisms affecting ceramic wall materials and provides a scientific basis for selecting durable construction materials and developing mitigation strategies for saline and arid environments.