考虑冻结壁的强制解冻过程,采用随机介质理论,建立了隧道水平冻结壁强制解冻期地表沉降的预测方法,并提出强制解冻条件下冻结壁温度场由单管解冻理论近似求解,基于所推导的单管解冻理论和崔托维奇提出的一维情况下融土层稳定融沉量公式,确定了预测方法中融土柱半径和融缩区域内半径的取值方法。将所建立的预测方法应用于隧道全断面水平冻结工程中,得到了地表沉降随强制解冻时间的分布及变化规律。研究结果表明,在冻结壁强制解冻期,其地表沉降分布规律与自然解冻期相似,但地表沉降随解冻时间呈线性增长趋势,这一特征与自然解冻期有所不同。
A method for predicting ground surface settlement in artificial thawing period of tunnel horizontal frozen wall is presented based on the stochastic medium theory. In this method, the artificial thawing process of frozen wall is taken into account, and the temperature field of frozen wall under artificial thawing conditions is approximately derived using the single-pipe thawing theory. Based on the calculation formulation for thawing settlement in the one-dimensional case proposed by ЦЫТОВНИЧ, the methods of calculating the thawing soil column radius and the inner radius of thawing contractive region are derived. The proposed methods are applied to predict the ground surface settlement during the artificial thawing process of a full-section horizontally frozen circular tunnel. It is found that ground surface settlement distribution in the artificial thawing period is similar to that in a natural thawing period, though the temporal variation of the ground surface settlement exhibits a linear growth trend, which is different from that of the natural thawing period.