Character And Evaluation Method Of Historical Rock Deterioration

Historical rock is the the base of stone buildings, stone structures and stone works of art. Because of the long term's influence of natural agents and human damage,the properties of historical rock had decayed even deteriorated. every year, there are a large increasing number of stone inscription art facing destruction.the existing evaluation method of the historical rock deterioration remains in generalities or confuses with the structural damage, and the dependent research system of the historical rock deterioration has not formed.With the help of Nation Nature Science Fund (No.40772167) and the scientific and technical research subject of State Adiministration of Cultrial Heritage in 2005 (2005011), this paper studies thoroughly three problems including the character, mechanism and evaluation method of historical rock deterioration. This study direction is the basic research project of stone cultural heritage preservation.At first ,This paper introduces the main types, characteristics and spatial distribution of historical rock in China. And then,this paper discusses systematically six parts,which are the classification of historical rock deterioration form, the investigation system of historical rock deterioration, the mechanismof the typical historical rock deterioration form, the effect mechanism of enviroment on the historical rock deterioration, the evaluation index and evaluation system of historical rock deterioration,the deterioration character and evaluation method of the rock surface of stone cultrial heritage.By way of practices of more than twenty stone cultural heritages in China,This paper puts forward a new historical rock deterioration form classification scheme that combining the international research with the chinese situation,which includes group,typical form and individual form three levels, the result is the first disease classification system for the study of cultural relic material in the field of cultrial heritage conservation in China.This paper studies systematicallythe investigation system of historical rock deterioration from investigation method and field testing technology. At the same time,it puts forward some technical directive rules for field testing and investigation. Combining field testing technology with laboratory analysis methods, this paper analyses systematically the character and the mechanism of five typical deterioration form from the surface change of physical character, chemical component, mineral component and microstructure ,the result shows that the long-term effect of water plays a decisive role in the historical rock deterioration. Throug the study of the accelerating deterioration test for four typical sandstone from north, westnorth, westsouth and south in China.the result shows that alternation of the wetting and drying and freeze-thaw action plays a decisive role in the sandstone deterioration ,the salt crystallization on the surface of rock affects also significantly in the sandstone deterioration. This paper research shows that the evaluation index and the evaluation system of historical rock deterioration is a new method that can help us half-quantitative to quantitative evaluate the present condition of the surface of historical rock, this result is the forword study result in the field of the stone cultural heritage preservation in word. This paper puts forward SWI(sandstone weathering index)and limestone deterioration evaluation index in the study of the deterioration character and evaluation method of the rock surface of stone cultural heritage . In them,The research of the regularity and correlation of the change of the engineering property and the internal component on the depth and time axis, which is the groundbreaking research method in the field of the stone cultural heritage preservation in world.