Partial Freezing Construction of Mine Main Inclined Shaft in Lijiaba Mine

ZHAO Yu-ming; ZHANG Xu-zhong; LIU Wei-min; LI Zhi-jun

doi:10.3969/j.issn.1002-6029.2014.04.005

Abstract：A mine main inclined shaft in Lijiaba Mine had an inclination of 20° and an inclined length of 1 440m. The mine inclined shaft was constructed with a partial freezing plan ,an initial freezing loca-tion had a horizontal distance of 250.41m to the mine inclined shaft head ,an inclined freezing length was 163.2m ,a horizontal length of the freezing section was 153.4m and the freezing length was divid-ed into 4 freezing section.There were six rows of the freezing boreholes set along the length direction of the mine inclined shaft and there were 455 freezing boreholes in total. The construction quality of the freezing boreholes was all meet the designed requirements. Partial thermal insulation measures were conducted on the freezing pipes in order to reduce the cold energy lost at the invalid freezing sec-tion and to save the cold energy. During the freezing process ,according to the measured temperature data ,an analysis calculation was conducted on the freezing soil expansion speed ,thickness of the freez-ing wall ,average temperature of the freezing wall and others and those data all could meet with the de-sign requirements. Since the excavation of the mine inclined shaft conducted ,site measurements were conducted on the temperatures of the mine shaft wall. From the excavated and exposed conditions ,the freezing effect was excellent ,an accuracy of the freezing analyzed data was verified and a safety mine shaft freezing and a safety excavation and lining operation were realized.