Study On The Relationship Between The Surface Area Dust Of The Statue And The Salt Deliquescence Disease In Plaster Of Statue

Clay sculpture is one of the oldest,most cultural products with the most ethnic flavor and national characteristics in China.The clay sculptures in the temples are magnificent and magnificent,as small as handicrafts and exquisite.However,in the long-term storage process,different degrees of surface pollution have occurred,which seriously affects its aesthetic appearance.Cultural relics protection scientists at home and abroad have carried out a series of studies on clay sculpture diseases,and found that the most severe diseases and surface pollution are the environment of clay sculpture,which is most closely related to this disease.It is of great practical significance to understand the movement law of the internal salt and foreign salt in the clay sculpture with the four seasons of the environment,to prevent the pollution of the clay sculpture salinization,and to provide reference materials for archaeologists.In this paper,the relationship between the surface area dust of the statue and the salt dehydration disease in plaster of statue is as follows:（1）The migration mechanism of water and salt in plaster of statue shows:1)The rise rate of the plaster of statue block in the compound salt solution is significantly faster than the capillary rise rate in distilled water.Whether it is in the compound salt solution or distilled water,the capillary rise rate of the coarse mud block is greater than that of the fine mud.The capillary rise rate of the statue mud block,the capillary rise rate of the mixed statue mud block is inferior to the coarse mud block and the fine mud block,the capillary rise rate of the statue mud block is higher than that of the unsalted statue mud block;coarse mud The test block is more prone to saline disease than the fine mud block.2)Test blocks of different heights appear at the top and bottom of the test block in both migration solutions.The water content in the middle of the sample is generally low due to the drying effect.The conductivity of the test block after the capillary rise in the two migration solutions The change trend is very different.When the migration solution is distilled water,the conductivity of plaster of statue block increases gradually according to the direction of capillary water.When the migration solution is a compound salt solution,the distribution of conductivity is the same as the distribution of water content.The situation is similar,showing a trend of high at both ends and low at the middle.3)When the compound salt solution undergoes capillary migration in the statue mud layer,the capillary front（top layer of the test block）is mainly enriched crystals of chloride and nitrate,while the area below the sub-front is mainly enriched crystals of sulfate.4)Comparison of original ion migration in the test block,coarse mud block>fine mud test block>mixed test block;4cm>3cm>2cm;unsalted test block>desalted test block.ions contained in the salt solution are in the test block Comparison of medium migration amount:coarse mud test block>fine mud test block>mixed test block;2cm>3cm>4cm;unsalted test block>desalted test block(Cl^-,SO₄^2-);desalinated test block>unsalted test block（Na⁺,K⁺）.5)After the capillary migration of the foreign salt in the compound salt solution,the damage to the plaster of statue mud block is more obvious.（2）The research on the deliquescence mechanism of salt in the air dust on plaster of statue showed that:1)Due to the existence of air humidity,the hygroscopic desorption causes the migration of salt in plaster of statue.Not only the salt in the higher part of the statue mud block is transferred to the bottom of the statue mud block,but also the salt on the surface of the test block.The ion concentration is generally high,which not only causes saline soil clay,but also affects its aesthetics.2)Air humidity has the greatest effect on salt migration when the statue mud block deliquesces.The higher the humidity,the greater the salt migration.When the temperature is25℃,the dustfall quality is 0.16 g/（30 cm²·2 a）,and the humidity is 97%,The amount of salt transfer is about 2.2mg;temperature mainly affects the speed of migration.When the test block is at 25℃and 60%humidity,the concentration of each ion increases rapidly in the first ten days of deliquescence,but in the late stage of deliquescence,the increase of salt It is not obvious that when the temperature continues to increase to 35℃,due to the violent movement of water molecules in the environment,the distance between the solid phase molecules is increased,and the higher the temperature,the weaker the hydrophilic ability between the soil particles,resulting in The water content and salt migration of the statue mud block are reduced;the migration is not only affected by air humidity and temperature,but the quality of dustfall also affects the migration of salt.When the dustfall quality is 0.16 g/（30 cm²·2 a）,It has the superiort impact on the salinization of clay plastics and increases the quality of dust.Its hygroscopic deliquescent forms floc and reduces the contact area with the statue mud block.On the contrary,the amount of salt migration is reduced.Factors,the presence of salt is the most critical factor.3)Humidity has the greatest influence on the migration of salt,and the migration of salt in the dust to the test block increases with the increase of humidity;temperature and quality have a great influence on the migration,the temperature is 25℃,and the mass is 0.16 g/（30cm²·2 a）,the maximum migration amount is 1.6mg.Therefore,in the future protection of clay sculpture,high humidity and low temperature environment should be avoided.（3）The relationship between the salt content in the surface area dust of the statue and the deliquescent disease of the water and salt in plaster of statue battle shows that:1)In the process of capillary water rising to the surface of the test block,the dedusting phenomenon of the test block and the surface of the test block also occurs at the same time,causing the salt in the dust to transfer to the statue mud block,and the transfer amount and the deliquescence time become direct ratio;2)After the combined action of water and salt migration and dedusting and deliquescence,the salt in the dust,the salt in the test block and the salt in the composite salt all accumulate on the top layer of the test block;causing a certain salt damage in the test block.3)There is a synergistic relationship between the salt content in the surface area of the statue and the deliquescent disease of the water and salt in plaster battle.The process of the migration of the soluble salt in the dust to the statue mud block mainly occurs after the capillary water soaks the test block,reaching moisture saturation At this stage,the longer the migration time of saturated water and salt,the greater the migration of salt from the dust to the test block.