人工冻土冻胀引发上覆地层与结构变形计算方法研究  

Title Calculation Method of Artificial Ground Frozen Soil Frozen and Heave Caused by Layers and Structural Deformation

作　　者：王磊 陈湘生[1,3,4] 伍军[4] 刘志强 WANG Lei;CHEN Xiangsheng;WU Jun;LIU Zhiqiang(China Coal Mine Engineering Company Limited,Beijing 100013,China;China Coal Research Institute,Beijing 100013,China;College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,China;China Railway Engineering Group Limited,Beijing 100055,China)

机构地区：[1]北京中煤矿山工程有限公司,北京100013 [2]煤炭科学研究总院,北京100013 [3]深圳大学土木与交通工程学院,深圳5180603 [4]中国铁路工程集团有限公司,北京100055

出　　处：《工程科学与技术》2024年第6期134-146,共13页Advanced Engineering Sciences

基　　金：国家自然科学青年基金项目(52008197);北京中煤矿山工程有限公司自立科技重点项目(KJZH-2024-ZD-01)。

摘　　要：人工冻结法在地下特殊施工中的冻胀风险引发广泛关注,上覆地表变形可能造成城市道路、建筑结构变形,继而引发破坏,需要对地表及结构变形进行预测。瞄准冻胀的实质是冻土中水分迁移引起的宏观表现,基于Peck公式计算思路,对冻胀引起的上覆地层变形进行公式推导和参数取值,得出适合计算冻胀变形的冻隆公式,以求解冻结过程中上覆地层产生的冻胀量。通过水分迁移试验测定冻结水分迁移速度,推导和归纳冻结外锋面半径经验计算方法,得出冻土体积增加量计算公式。以郑州某冻结工程实测数据,计算土体冻结过程中的水分体积增加率,冻隆公式计算值与实测值接近,满足施工过程中安全评价分析的需求。研究成果可为人工冻结技术在高风险地下工程领域的技术研究应用提供理论基础和计算参考。Objective The artificial ground freezing method is widely applied in the construction of tunnels through highly saturated soft soil layers.However,the phenomenon of frozen soil expansion can adversely effect the safety of overlying structures.As the number of projects involving this freezing method beneath such structures continues to increase,scholars are increasingly concerned about the deformation of these structures caused by frost heave.Despite this,the calculation methods and interaction laws governing the deformation of overlying structures during the freezing process remain unclear,highlighting the need to predict surface and structural deformations.This study aims to address the frost heave issue related to the macroscopic manifestation of water migration in frozen soil.Methods It derives formulas and parameter values by using Peck’s equation to calculate the deformation of overlying strata induced by frost heave.Consequently,it establishes an appropriate frost heave formula to compute the amount of frost heave generated during the freezing process.Based on construction experience,the study provides a range of reduction coefficients for frost heave in various cities.Through moisture migration experiments,the velocity of water migration during freezing is determined,and an empirical calculation method for the radius of the freezing front is derived.Additionally,a formula to calculate the increase in volume of frozen soil is developed.By comparing and analyzing the dimen-sions of frost heave mounds under different freezing wall diameters (3.0, 4.8, 5.2, and 6.0 m), it is discovered that the sizes of frost heave mounds produced by different diameters are nearly identical. Results and Discussions It is found that the burying depth of the freezing wall (z0) has a significantly greater impact on the shape of the frost heave mound curve than the diameter of the freezing wall. Thus, the burying depth of the freezing wall emerges as a crucial factor influencing the size of the frost heave mound in overlying str

关 键 词：人工冻结法 冻土体积增加量 水分迁移 冻胀 冻隆公式 

分 类 号：TU94[建筑科学—建筑技术科学]