Studies Of Chinese Traditional Lime Mortar' Scientificity And Its Protection In Immovable Culture Relic

During the long history,there are numerous unmovable cultural heritages in China.These cultural heritages are usually very huge and lie in the open air.Due to natural weathering,environmental pollution with the development of modern industry,human factors and lack of effective protection technology and consciousness,these precious historical heritages are suffering a great destruction.Some even have died out.Thus we should take action to protect these cultural relics as soon as possible.This paper summarizes the development and the existence questions of the modern protection of cultural heritages including the research of moderrn materials,imitation of ancient mortar and establish of analytical methods.Based on the development tendency of protection materials for cultural heritage and the previous work of our laborotary,the analytical method of organic additives in lime mortar,the mechanism and application of traditional mortar for the conservation of unmovable cultural heritages have been studied in this work.The following are the main points:A method for the analysis of organic additives in lime mortar was established.Different lime mortars have different compositions,ratios,applications and properties.In this work a set of analytical procedures to identify the organic additives in lime mortars by classical chemical analysis is proposed.The results show that using iodine-potassium iodide reagent,Benedict's reagent,reduction phenolphthalein reagent,Coomassie brilliant blue and sodium periodate oxidation glycerin acetyl acetone method could effectively detect a small amount of starch,reducing sugar,blood,protein and fatty acid ester remained in ancient buildings' lime mortars respectively.And we use this method analyzed 13 ancient samples,the results are very close to the results of FT-IR analysis.Moreover,these analytical methods are easy to operate with low detection limit,high accuracy and some other advantages.The mechanism and imitation of traditional tung oil-lime mortar were studied.Tung oil-lime mortar is a special organic-inorganic binding'material invented by the ancient Chinese people.It was widely used as a binder in wooden ship,special moistureproof structure of ancient buildings and sites due to its good sealing and waterproofing performances.In this paper,the analytical results of a piece of chu-nam putty which was discovered in "Huaguang No.1" ancient ship are presented.The results show that the components of chu-nam putty are calcite,carboxylate,unsaturated esters by means of FT-IR,XRD and TGA/DSC.And through FT-IR and cross-section analysis confirm that the oakum from jute.Comparing with the modeling putty it is found that the outstanding sealing performance of chu-nam putty comes from the coordination reaction of Ca2+ from the Ca(OH)2 and the oxidation aggregation reaction of C=C double bonds in unsaturated fatty acid.And the results of performance test show that the mortar which is prepared by tung-oil with calcium hydroxide has better mechanical properties,waterproofness and weather resistance.The application and modification of sticky rice-lime mortar were studied.According to the ancient records and using expanding agent to reduce the shrink cement,we use aluminum sulfate,alum,gypsum to modified traditional sticky rice-lime mortar to reduce its shrink.Results indicate that aluminum sulfate improves the mechanical property,freeze-thaw resistance and water resistance of sticky rice-lime mortar obviously.Alum mostly improves the mechanical property of sticky rice-lime mortar.While gypsum has few contribution to mechanical property and weather resistance of sticky rice-lime mortar.All of these three admixtures have well effect on slowing down and reducing the shrink of sticky rice-lime mortar.Aluminum sulfate should be used as admixtures of sticky rice-lime mortar in conservation of cultural relics.