Study Of Simulated Experiment On Hydrothermal Change In The Artificially Wall Of Earthen Architecture Sites

The deterioration of earthen Sites is one of the most complicated issues of conservation. The temperature and the moisture are two important for analyzing the deterioration Mechanism of earthen Sites.Semiconductor Si sensors were used to monitor the temperature changes in an artificially rammed earthen wall at the ruins of Jiaohe in Xinjiang, China. Test data show that temperatures at interior points near west wall and south wall surface changed more greatly than that at other sides due to longer exposure to sunlight. An obvious temperature gradient was observed from the surfaces to the inner core of wall, indicating a potential of differential expansion-extraction deformation of soil particles resulting from changes in the temperature of the atmosphere.Additionally, Time Domain Reflectometry (short for TDR) was used to monitor the moisture changes in the wall. Test data show that moisture at interior points near west wall surface changed greatly, but its value were lower, indicating water movement in the west wall surface is the most active. The moisture underground is higher in the deeper position, but lower in the south of the same depth. The results show that solar radiation promotes the water movement.Based on the resistivity model laboratory experiment, the relationship between moisture and resistivity was obtained by using silty clay of the wall. The high density resistivity method was used to monitor moisture continuously after the artificial rain test. The moisture inversion was retrieved based on the resistivity in the wall at the ruins of Jiaohe. Date show that moisture infiltrates into the surface with time gradually. The variation of temperature and moisture is almost same, based on monitoring temperature and moisture in different seasons. However, the time of peak of temperature and moisture are a little different, influenced by solar activity closely. The maximum and minimum of temperature and moisture are same, which is higher in August, lower in November. The difference between maximum and minimum are different, higher in August. According to Comprehensive analysis of data, the empirical formula between temperature and moisture is Boltzmann function, and the value of R~2 is about 0.9.