Site Measurement Study on Temperature Filed of Freezing Wall and Mine Shaft Liner in Ultra Thick Clay Stratum

YANG Guo-qiang; JIANG Guo-jing; GAO Wei; MA Guan-chao

doi:10.3969/j.issn.1002-6029.2014.03.017

Abstract：An auxiliary shaft of Zhangji Mine was a deep mine shaft.There was an ultra thick clay stra-tum with a thickness of 169m located in the mine shaft at a depth section from 280.52~449.69m.The ultra thick clay stratum was swelling thick clay mainly and was a single highest thick clay stratum pas-sed by a mine shaft in China.According to the thickness of the mine internal and external shaft liners and the different grade of the concrete strength ,there were 6 monitoring and measuring levels set in the mine shaft and a site measurement study was conducted on the temperatures fields of the freezing wall and the mine shaft liner in the clay stratum.The results showed that due to influenced by the ini-tial hydration heat emission of the concrete and the refrigeration supply of the freezing pipe ,a tempera-ture variation curve of the external shaft liner would have three stages obviously and they were a linear rapid increasing stage ,nonlinear rapid decreasing stage and stable stage.An inner temperature varia-tion tendency of the freezing wall was relatively mild and was in a minus temperature state al-ways.Within two days after the concrete poured in the mine shaft external liner ,the freezing soil ground near the mine shaft liner would reach a max thawing distance about 200mm.With 12~14 days after the concrete poured in the mine shaft external liner ,the thawing soil near the mine shaft liner would be first in a minus temperature state and that is a refreezing phenomenon was occurred.Foamed plastic boards set between the mine shaft freezing wall and external liner could reduce an interaction between the concrete hydration heat and the refrigeration supply of the freezing pipe in a certain de-g ree.