水泥改良对地层冻结温度场影响分析

Influence of Cement Soil on Stratum Freezing Temperature Field

针对目前对于水泥改良土地层冻结温度场研究较少的问题,基于福州地铁2号线某联络通道冻结工程,对积极冻结期水泥改良土地层冻结温度场进行数值模拟,结果表明冻结温度场和冻结壁的发展速度分别在冻结初期和中期较为迅速,冻结管主面的冻结效果优于界面,冻结管排间土体的冻结效果优于冻结管布置圈内外两侧的规律;并通过模拟不同水泥掺量条件下的地层冻结,得到结论:土体冻结效果随水泥掺量的增大呈先增强后减弱的趋势,当水泥掺量为10%时,土体的冻结效果最佳;原状土地层的冻结效果要优于该工程实际水泥掺量(20%)地层。研究结果为今后水泥改良土地层冻结工程提供参考和借鉴。

To study the freezing temperature field of the cement-modified soil stratum,taking a connected aisle of Fuzhou Metro Line 2 as the example,numerical simulation was conducted during active freezing period.Results show that the developments of freezing temperature field and freezing wall were relatively rapid in early and middle stages of freezing period.The freezing effect was better on the main surface of the freezing pipes than that of the interface,and better between the rows of freezing pipes than that of the inner and outer sides of the layout circle of freezing pipes.By simulating the stratum freezing under different cement content,it was found that the soil freezing effect increased first and then weakened with the increase of cement content.At the cement content of 10%,the soil freezing effect was the best.In addition,the freezing effect was better in undisturbed soil stratum than that of the cement content(20%)stratum applied for the project.The research findings provide a reference for the future freezing project of cement soil stratum.