Deterioration of Yungang Grottoes: Diagnosis and research

Yungang Grottoes, in Datong City of Shanxi Province, China, as the state-level key cultural relic preservation organ, have been subjected to severe degradation due to natural and human factors over the years. Since January 2010, site investigation and research on Yungang Grottoes, assisted by the Xi’an Relics Protection Center and Yungang Grottoes Cultural Research Institute, have been carried out in the laboratory of cultural relics conservation materials in Zhejiang University. Our investigation of the deterioration characteristics of these grottoes is presented here. The paper describes about 12 types of diseases in detail represented by dust deposit, salt crystallization and black crust. Relevant samples have been collected and analyzed by means of SEM, FT-IR, XRD and EDAX to study the potential hazard to the sandstones and conservation methods, which could be used to help guide remediation efforts directed at reducing the weathering problem.