【摘要】 西安城墙的墙体常大面积析出白色盐粉,这种现象被称为"泛碱"。大量出现的泛碱现象不但大大影响西安城墙的整体美感,而且会降低砖材的力学强度造成脱落、粉化等病害,甚至对墙体的稳定性和安全性都造成威胁。为了了解其产生的原因,本工作通过X射线衍射分析方法对泛碱物质进行分析。分析结果表明,泛碱主要成分为NaCl、NaNO3、Na2SO4.10H2O、无水芒硝。结合对西安地区环境地下水和降雨等资料的调查,认为"泛碱"的主要原因为原材料以及地下水、雨水等引入的可溶盐。针对这一现象,提出了用"多层纸张贴敷法"除去导致砖石表面酥粉泛碱的可溶盐,再后期杀菌封护的保护方案。更多还原

【Abstract】 Efflorescence often appears on the city wall of Xi’an,forming large areas of white crystalline salts.Efflorescence causes cosmetic damage and can reduce the mechanical strength of the bricks,which leads to peeling and powdering,and even threatens the stability and safety of the wall.To investigate the cause of efflorescence,the crystalline salt was analyzed using XRD.The results showed that the major components are NaCl,NaNO3,Na2SO4·10H2O,and Na2SO4.Based on groundwater and rainfall data for the Xi’an area,the major cause of efflorescence is the introduction of soluble salts from construction materials,groundwater and rainfall.A conservation method against efflorescence was developed,first removing the surface salts with multiple layers of paper,following by sterilization and insulation.更多还原