A Quantitative Study On The Weathering Disease Of Yungang Grottoes By The Three-dimensional Reconstruction Technology Of Multi-view Images

This article is focusing on part of the Thousand Buddhas Statues in YunGang Grottoes,mainly discussing the corresponding scaling relationship between different levels of weathering.By doing field survey,based on the disease investigation and testing accuracy of photogrammetry results.This paper investigated some of the Thousand Buddhas Statues in grottoes number 15 and number 16-1.Firstly,Author collected the photo image and location information by doing field survey,then analyzed and processed that information.Secondly,Author separately measured and calculated three parts of the statues,they are head,chest,and feet of the statues.Author also compared the result with a preset datum line to get the distance from each part to datum line and scale factor difference.Finally,Author put the results in different classes,according to the scaling relation.According to the researches,this paper got the following conclusion.Firstly,the head part of the statues can be separated to three classes given their weathering level.First class is well-preserved which scaling relation is both in upper datum line less than 60%and in lower datum line greater than 35%.Second class is defected which scaling relation is both in upper datum line between 60%and 100%and in lower datum line between 0%and 35%.Third class is nonexistence which scaling relation is both in upper datum line greater than or equal to 100%and in lower datum line less than or equal to 0%.Besides,this kind of statues do not sculpture face when it was sculptured.Secondly,the chest part can also be separated to three classes:well-preserved with clothes,well-preserved chest without clothes,and nonexistence.The first class,well-preserved with clothes,which ratio is both of the distance that is from chest to upper datum line to the distance between upper and lower datum line is less than 65%and of the distance that is from chest to lower datum line to the distance between upper and lower datum line is greater than 10%.In the second class,well-preserved chest without clothes,the ratio of distance between chest and datum line to the upper and lower datum line distance is both from 65%to 100%of the upper datum line and greater than 0%of the lower datum line.The third class,nonexistence,which scaling relation is both in upper datum line greater than or equal to 100%and in lower datum line less than or equal to 0%.Thirdly,the feet part can be separated to two classes:existing and non-existing.The distance between feet and datum line in the first class is greater than 0 and less than 20mm.The distance between feet and datum line in the second class is greater than or equal to 20mm.Overall,by combining the different classes of the three parts,we can separate the statues into four classes.