斜井冻结和解冻全过程温度场演化规律研究

针对斜井冻结中存在的井壁浇筑水化热释放、局部冻结方式等问题，采用数值模拟和现场实测方法对袁大滩煤矿副斜井冻结和解冻全过程温度场的发展演化规律进行了研究，对斜井支护方式、停止冻结时间和局部冻结结构形式进行了探讨。结果表明，局部冻结时在非冻结段采用小尺寸冻结管或聚氨酯发泡方式的局部冻结效果并不理想，建议将局部冻结管做成双层套管，两层冻结管之间设置保温层，以维持聚氨酯材料的保温性能、减少冻土体积、减少制冷量的额外消耗|井壁水泥水化热的释放会造成井壁内部温度较高和周围的冻土融化，建议在外层井壁和冻土之间设置木背板或泡沫板等隔热材料，防止井壁内外温差过大而产生温度裂缝|根据井壁强度增长情况，确定合理的停止冻结时机。

Study on the evolution law of temperature field in the whole process of inclined well freezing and thawing

Aiming at the problems of hydration heat release and local freezing mode in inclined shaft freezing, this article studied the development and evolution law of temperature field in the whole process of freezing and thawing in the auxiliary inclined shaft of Yuandatan Coal Mine, as well as the supporting mode, stopping freezing time and local freezing structure of inclined shaft, using numerical simulation and field measurement method. The main conclusions are concluded as follows, 1) The local freezing effect of using small size freezing pipe or polyurethane foaming method in non-freezing section is not ideal. It is suggested that the local freezing pipe be made into double-layer sleeve and insulation layer be set between the two freezing pipes to maintain the thermal insulation performance of polyurethane material, reduce the volume of frozen soil and reduce the additional consumption of refrigeration capacity. 2) The release of cement hydration heat in shaft lining will cause higher temperature inside the shaft lining and melting of surrounding frozen soil. It is suggested to set up insulation materials such as wood backplane or foam board between outer shaft lining and frozen soil to prevent temperature difference between the inside and outside of the shaft lining and produce temperature cracks. 3) Reasonable stop freezing time should be determined according to the increase of shaft wall strength. The research results in this paper can provide reference for the following inclined shaft freezing engineering.