Study On The Protection Against Weathering And Reinforcement Of Tongwancheng Site

Tongwan city is the only discovered capital city ruins which was founded by Huns in 413,1600 years ago.It is of great historical,artistic and scientific value to further study of Wuhu 16.It is located in Mu Us Sandy Land,one of Chinese Four Sand.In ancient times there were beautiful country scene,but after many years of ecological deterioration,Tongwan city has been deep in endless sand.Nowadays,There are a variety of typical diseases damaging Tongwan city,including surface stripping,undercutting,biodeteriorating and man-made sabotage.If no action to protect it,the great city may will face the permanent disappearance.To solve the above-mentioned problems,this paper carried out the following work.1.Investigated the diseases of Tongwan city.There are so many earthen ruins and diseases in our country.Only by particular investigation,we can suit the remedy to the case.Blind work may create a disaster.2.Analyzed the specimen and image data of Tongwan city.That included sample characterization analysis,disease genetic analysis and so forth.The internal cause and external cause work together to damage Tongwan city.The disease causes which have been discovered are crack,wind erosion,rain erosion,salt stress,biodeterioration and man-made sabotage.3.Designed a creative aeolian dynamics experiment.Wind erosion and salt stress are key factor to damage the Tongwan city.This creative experiment demonstrate that these two factors are related to each other because the amount of wind erosion in 40 minutes of salted sample is much more than desalted sample.On the one hand,the process of dissolution-crystallization-redissolution of salt leads to a damage of interior structure in soil and the collision of sediment-carrying wind deteriorates the damage.On the other hand,wind erosion causes tough irregular surface,cohesionless soil and larger cracks,which further force the occurrence of salt stress.These two factors work together to form a vicious circle.4.Found an optimized reinforcement material for Tongwan city.According to the above analysis,the four most common reinforcement material were used for performance test to choose an optimized one.The performance test demonstrated that CB material showed good performance in aberration,quality variation,pH,breathability,compression strength,water resistance,freeze-thaw stability and anti-wind erosion properties.5.Applied CB material to two simulated earthen sites.CB material has been applied to many protection projects of earthen ruins from 1990.And this time,it was applied to two simulated earthen sites in our center and confirmed that there are lesser surface stripping,undercutting salt stress and crack in the reinforced portion.6.Reinforced the some sections of Tongwan city in April,2016.Four sections(5m2 per section)of north of the rampart were reinforced by CB material and were observed that the abilities of anti-weathering and soluble-salt governance were superior to unreinforced area in nearly a year.That further confirmed CB material is optimized to Tongwan city.