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介绍了中国矿山冻结法凿井井壁混凝土温度问题的现状和发展,研究了井筒冻结相变导热环境下大体积混凝土井壁温度场数学模型;介绍了营盘壕冻结副立井套内壁的工程概况、垂深704m壁座结构和温度监测方案,7个实测点数据,图形展示了混凝土浇筑72h内井壁及围岩的实测温度发展.有限元数值模型计算获得了对应实测点的温度数据,和实测结果相当接近,并预测了在停止冻结后直至全部融化的井壁及围岩温度分布发展情况.数值计算还原了井壁距内缘深682mm测点2的一段丢失数据,弥补了对测温量程考虑不足导致数据丢失的遗憾,并显示出在混凝土搅拌后37.5h时井壁测点最高温度可达到92.3℃,高温发生在内壁中间部位,井壁内外温差最高达到了65℃以上,如此高的内外温差值得设计和施工人员关注.模型还揭示了停冻120d后冻结壁全部融化,即围岩都上升到摄氏正温以上.
This paper introduces the current situation and development of the freezing temperature method for mine shaft lining concrete temperature in mine in China, studies the mathematical model of the temperature field of the large-volume concrete shaft wall in the condition of thermal conductivity in the freezing phase change of wellbore, introduces the general situation of the inner wall of the auxiliary shaft casing in Yingpan trench freezing, The structure and temperature monitoring plan of 704m deep vertical wall and the data of 7 measuring points show the measured temperature development of wellbore and surrounding rock within 72h of concrete pouring.The temperature data corresponding to the measured point are calculated by FEM numerical model and the measured The results are quite close and predict the temperature distribution of wellbore and surrounding rock after it has been frozen until it is completely thawed.Numerical calculation restores the missing data of a 682mm measuring point 2 from the inner edge of the borehole to make up for the temperature measurement range Considering the lack of data lead to the regret, and show that 37.5h after the concrete wall when the measured point of wellbore temperature can reach 92.3 ℃, high temperature occurred in the middle of the inner wall, the wall temperature difference between inside and outside the highest reached 65 ℃, so high The temperature difference between inside and outside should be of concern to designers and constructors.The model also reveals that the frozen wall is completely thawed after 120 days of freezing, that is, the surrounding rock has risen to a positive temperature of Celsius .