隧道冻结法施工引起地表冻胀预测模型的参数敏感性分析

隧道水平冻结施工过程中,土层冻结体积膨胀,引起地面上升和变形,过量的变形会对周围地表建筑物产生危害。本文结合工程实例,验证了冻结壁交圈后隧道水平冻结施工引起地表冻胀位移的历时预测模型的可靠性。通过参数敏感性分析得到了反映冻结温度场发展速度的常数A对地表冻胀位移的敏感性最强,而冻结管布圈半径Rd对地表冻胀位移的敏感性最弱,土体冻胀率的变化率可近似反映地表垂直冻胀位移的变化率。本文的研究成果可为今后水平冻结法的设计和施工提供参考依据。

The Parameter Sensitivity Analysis of The Duration Prediction Model of Surface Frost Heave Induced by Tunneling with Horizontal Freezing Method

In the process of tunneling with horizontal freezing method, soil volume expansion caused by freezing can produce the ground rise and deformation, excessive deformation may damage the surrounding surface buildings. This paper com-bined with engineering example, verified the reliability of the duration prediction model of surface frost heave after the circlecrossing period of frozen wall induced by tunneling with horizontal freezing method. Through the sensitivity analysis of parameters, obtained the constant A which reflects the freezing temperature field velocity is the most sensitivity to the surface frost heave, the radius of freeze pipes distribution circle Rd is the weakest sensitivity to the surface frost heave, changes of the rate of the frost heaving rate can be approximated reflects changes of the rate of the surface vertical frost heave displacement. Results of this study may provide reference for the design and construction of future horizontal freezing method.