论文部分内容阅读
为获得多圈管冻结壁形成与融化过程中冻结壁内部冻胀力发展特性和孔隙水压力变化规律,进而分析冻结壁力学性态及安全性,在淮南某煤矿开展了冻结壁冻融过程中内、外部冻胀力和孔隙水压力的现场实测研究.实测结果表明:在地层冻融过程中,冻结壁内、外部形成了不均匀的冻胀应力,测试地层最大冻结压力达6.0 MPa,为初始地压的2.4倍;当井筒开挖至测试层位时地层冻结压力呈线性降低;随着浇筑外层混凝土井壁,冻结压力又有回升,当冻结壁融化后地层冻胀力为零,井壁恢复受水土压力作用.孔隙水压力变化经历了静止孔隙水压力和冻结过程的超静孔隙水压力两个阶段,超静孔隙水压力达到4.0 MPa,约为静止孔隙水压力的2.0倍.
In order to obtain the developmental characteristics of frost heaving force and the variation of pore water pressure in the frozen wall during the formation and melting of the multi-circular tube, and analyze the mechanical properties and safety of the frozen wall, in a coal mine in Huainan, Internal and external frost heave and pore water pressure.The results show that in the process of freeze-thaw formation, the frost heaving stress is not uniform in the freezing wall and the maximum freezing pressure of the test formation is 6.0 MPa, which is Initial pressure 2.4 times; when the wellbore excavation to the test horizon when the formation of a linear decrease in freezing pressure; with the outer wall of concrete pouring, the freezing pressure has picked up, when the freezing wall melting frost heaving force is zero, The wellbore restoration is affected by both water and earth pressure.The pore water pressure undergoes two stages of static pore water pressure and the excessively static pore water pressure during the freezing process. The excess pore water pressure reaches 4.0 MPa, which is about 2.0 times of the static pore water pressure.