季节性非饱和冻土地温监测及冻胀特性THM耦合模拟  

Ground Temperature Monitoring and THM Coupling Simulation of Frost Heave Characteristics in Seasonal Unsaturated Frozen Soil

作　　者：王莉莉[1] 刘英杰 胡肖 李鹏辉 付世博 姜伟 张钰[1] WANG Lili;LIU Yingjie;HU Xiao;LI Penghui;FU Shibo;JIANG Wei;ZHANG Yu(School of Civil Engineering,Northeast Petroleum University,Daqing 163318,Heilongjiang China;Daqing Yellow and Light Storage Research Co.Ltd.,Daqing 163515,Heilongjiang China;College of Civil and Hydraulic Engineering,Heilongjiang Bayi Agricultural University,Daqing 163319,Heilongjiang China)

机构地区：[1]东北石油大学土木建筑工程学院,黑龙江大庆163318 [2]大庆黄和光储实证研究有限公司,黑龙江大庆163515 [3]黑龙江八一农垦大学土木水利学院,黑龙江大庆163319

出　　处：《河南科学》2023年第12期1798-1807,共10页Henan Science

基　　金：黑龙江省重点研发计划指导项目(GZ20220028)。

摘　　要：季节性冻土的冻胀融沉影响当地建筑物与构筑物的结构安全,找到地温随时间的变化数据可推算时间域内冻胀融沉对地面建筑的影响规律.以大庆市非饱和冻土为例,基于热传导理论和非饱和土渗流理论,在原位地温监测数据的基础上,建立了冻土的含相变过程的热-流-固(THM)三场耦合数值模型.通过数值模拟结果与实测结果的比较验证了冻土模型的准确性.结果表明:地温随地表温度呈延时周期性变化,在地面以下2.0 m以内,深度每增加0.5 m,温度波峰和波谷日大约推迟30 d;冻结期持续时间影响冻结深度,从而对当地土的周期性冻胀量起决定性影响,冻结期内土的每年最大冻胀位移为30.0 mm左右,冻结期结束后地面高度将快速恢复到冻结期之前的水平,季冻区冻胀融沉敏感性建筑物及构筑物的基础施工时间选择在冻结期结束后2个月至冻结期开始前,可有效减少冻胀融沉危害,大庆及其他类似季节性冻土地区的土壤冻融和冻融过程中的水热迁移研究可作为借鉴.The frost heaving and thawing settlement of seasonal frozen soil affects the structural safety of local buildings and structures.The influence law of frost heaving and thawing settlement on ground buildings in the time domain can be calculated by finding the data of ground temperature change over time.Taking Daqing unsaturated frozen soil as an example,based on heat conduction theory and seepage theory of unsaturated soil,a THM(thermalfluid-solid)three-field coupling numerical model of frozen soil with phase transformation process was established based on in-situ temperature monitoring data.The accuracy of the frozen soil model is verified by comparing the numerical simulation results with the measured results.The results show that the ground temperature changes periodically with the surface temperature delay,and the peak and trough of temperature will be delayed about 30 days for every 0.5 m increase in depth within 2.0 m below the surface.The duration of the freezing period affects the freezing depth and thus has a decisive influence on the periodic frost heaving amount of local soil.The maximum annual frost heaving displacement of soil during the freezing period is about 30.0 mm.After the freezing period,the ground height will quickly recover to the level before the freezing period.The foundation construction time of buildings and structures sensitive to frost heaving and thawing settlement in the seasonal frozen region can be selected from the two months after the end of freezing period to the time before the beginning of freezing period,which can effectively reduce the damage of frost heaving and thawing settlement.The research on soil freezingthawing and hydrothermal transfer in the freezing-thawing process in Daqing and other similar seasonal frozen regions can be used for reference.

关 键 词：季节性冻土区 冻胀融沉 THM耦合 地温场 

分 类 号：P642.14[天文地球—工程地质学]