纸条检测法对第85窟壁画空鼓灌浆脱盐效果的评估

The Assessment of Salt Exclusion Effect with Paper Strip of Salt Spot Test for Mural Detachment Grouting in Cave 85 of the Mogao Grottoes

实验得出不损伤壁画的纸条检测法与壁画表面盐分含量的关系,并以此为根据,采用纸条法测定壁画表面盐分的含量状态,评价壁画空鼓灌浆后脱盐的效果。结果表明壁画空鼓灌浆所带入的水分激活了地仗中的盐分,使盐分运移并大量地富集到壁画的表面。保护笔的脱盐效果十分显著,纸条法测得保护笔脱盐后Cl-浓度降低约10个ppm,相当于保护笔脱盐可以减少了壁画表面地仗中所含1.6%的Cl-的量,即可以去除掉未灌浆区域壁画表面盐分的80%。实验证明纸条法可以应用于壁画脱盐效果的检验。

Base on the relation which the Non-Destructive paper strip of salt spot test and the salinity content on the surface of mural,adopt the paper strip of salt spot test to determine the salinity content on the surface of mural and assess the effect of salt exclusion.The result showed that water brought by grouting activize the salt in clay-based layer of mural.The water carry the salt and make them deposit on the surface of mural.The effect of salt exclusion which using conservation pen is notable.The paper strip of salt spot test showed that consistence of Cl-decrease about 10 ppm by use the conservation pen,equal to reduce the salt 1.6%(by weight).Namely,the conservation pen can remove the salt 80% on the surface of mural at no-grouting area.Experiment proved that the paper strip of salt spot test can be used in verify the effect of mural salt exclusion.