西安明城墙土体微溶盐-可溶盐测试与分析

Analysis on the Slightly Soluble Salt and the Soluble Salt in Xi'an City Wall

西安明城墙的土体中存在的盐分及其运移导致的泛白、表面酥解、掏蚀等病害,采用电导法、化学分析法及X射线衍射分析法测定了微溶-可溶盐的成分及含量。结果表明,西安明城墙土体中的计算微溶-可溶盐总量4.40 g·kg-1以上,主要以硫酸钙、硝酸钠、硫酸钠、碳酸钙、氯化镁等形式存在,且不同部位盐分含量和存在形式有差异。这些研究以期为城墙盐分病害防治提供依据。

There are many diseases caused by the slightly soluble salt and the soluble salt and its migration, such as surface whitening, the surface crisping, the surface undercutting, and so forth. The components and contents of the salts were analyzed by conductivity analysis, chemical analysis and XRD（X-ray diffraction analysis）. The results showed that the total content of the slightly soluble salt and the soluble salt calculated was more than 4.40 g·Kg-1, and the main components of it was the calcium sulfate, sodium nitrate, sodium sulfate, calcium carbonate, magnesium chloride. It existed in the diversified forms and different contents of salts among the different segments of the wall. It is provided a basis for researchers to treat these diseases and to protect the wall.