Li Qiang, Wang Zhongwei, Guo Han, Zhao Jing, Luo Hongjie, Huang Xiao
School of Materials Science and Engineering, Shanghai University, Shanghai, 200444, China.
Institute for the Conservation of Cultural Heritage, Shanghai University, Shanghai, 200444, China.
Sci Rep. 2024 Oct 9;14(1):23510. doi: 10.1038/s41598-024-74645-5.
Salt efflorescence is one of the major hazards to cultural heritages, masonries, and highways etc. It is now generally accepted that damages caused by salt efflorescence are mainly due to continuous cycles of salt crystallization/dissolution or hydration/dehydration in confined spaces. The position where salt efflorescence occurs and its type are closely related to the degree of damages caused by salt efflorescence. It is known that water is the key environmental factor determining the salt crystallization position. But influence of the correlation between water supply and evaporation on the position of salt crystallization is still not clearly understood. In this work, a set of experiments are designed to investigate salt efflorescence in porous matrix. It is found that the types and positions of salt efflorescence have little to do with nucleation, but are mainly governed by crystal growth, which is controlled by the rates of water evaporation, water and salt supply, capillary forces and surface properties of the porous matrices.
盐析是文化遗产、砖石建筑和公路等面临的主要危害之一。目前人们普遍认为，盐析造成的损害主要是由于在有限空间内盐结晶/溶解或水化/脱水的持续循环。盐析发生的位置及其类型与盐析造成的损害程度密切相关。众所周知，水是决定盐结晶位置的关键环境因素。但是，供水与蒸发之间的相关性对盐结晶位置的影响仍不清楚。在这项工作中，设计了一组实验来研究多孔基质中的盐析现象。研究发现，盐析的类型和位置与成核作用关系不大，主要受晶体生长控制，而晶体生长又受水蒸发速率、水和盐的供应、毛细作用力以及多孔基质的表面性质控制。
