西部侏罗系深基岩立井冻结温度场实测与分析

In-situ Measurement and Analysis of Freezing Temperature Field of Shaft in Western Jurassic Stratum Deep Bedrock

为掌握西部侏罗系地层深基岩立井冻结温度场发展规律,根据新街矿区红庆河煤矿二号风井井壁厚度及混凝土强度等级的不同,布设各监测水平,对冻结法凿井期间井壁与冻结壁温度进行现场实测,得到了该地区在特定条件下的温度场变化规律。结果表明,壁座大体积C70混凝土浇筑后,30-36h内水化热达到峰值,测到的最高温度为71.32℃,升温速率基本为40℃/d,降温速率为4℃/d左右。外壁温度变化可分为3个阶段,即线性急速上升阶段、非线性快速下降阶段和趋于稳定阶段。混凝土配合比决定了水化热的升温强度,井壁厚度决定了水化反应的时间跨度。

To master the development law of freezing temperature field of shaft in western Jurassic stra ‐tum deep bedrock , according to the thickness of shaft liners and the different grade of concrete strength of Hongqinghe Coal Mine No.2 air shaft in Xinjie Mining Area ,monitoring and measuring levels were set and a site measurement study was conducted on the temperature of the shaft liner and the freezing wall during freeze sinking ,temperature field variation law of the region in certain freezing conditions was obtained. The results indicate that the heat of hydration of the C 70 mass concrete in shaft crib points reaching the maximum of 71.32 ℃ within 30 - 36 h ,the heating rate is about 40 ℃ /h and the cooling rate is around 4 ℃ /d. The temperature variation of the external shaft liner would have three stages and they were a linear rapid increasing stage ,nonlinear rapid decreasing stage and stable stage. The concrete mix determines the heating degree of hydration heat and the thickness of shaft lin‐er determines the time span of hydration heat.