关键词: 斜井冻结, 解冻, 局部冻结, 水化热

Abstract: 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.