基于冻融次数-物理时间比拟理论的冻土长期强度预测方法  

Freeze-thaw cycles-physical time analogy theory based method for predicting long-term shear strength of frozen soil

作　　者：张泽 马巍[2] ROMAN Lidia MELNIKOV Andrey 杨希 李宏璧 ZHANG Ze;MA Wei;ROMAN Lidia;MELNIKOV Andrey;YANG Xi;LI Hong-bi(Institute of Cold Regions Science and Engineering,School of Civil Engineering,Northeast Forestry University,Harbin,Heilongjiang 150040,China;State Key Laboratory of Frozen Soil Engineering,Northwest Institute of Eco-environment and Resources,Chinese Academy of Sciences,Lanzhou,Gansu 730000,China;Coordinated Innovation Center for Permafrost Environment and Road Construction and Maintenance in Northeast-China,Northeast Forestry University,Harbin,Heilongjiang 150040,China;Department of Geocryology,Faculty of Geology,Lomonosov Moscow State University,Moscow,Russia;Melnikov Permafrost Institute,Siberian Branch,Russian Academy of Science,Yakutsk,Russia;Yalong River Hydropower Development Company,Chengdu,Sichuan 610051,China)

机构地区：[1]东北林业大学土木工程学院寒区科学与工程研究院,哈尔滨黑龙江150040 [2]中国科学院西北生态环境资源研究院冻土工程国家重点实验室,甘肃兰州730000 [3]东北林业大学东北多年冻土区环境、道路建设与养护协同创新中心,哈尔滨黑龙江150040 [4]罗蒙诺索夫莫斯科国立大学地质系冻土学教研室,俄罗斯莫斯科 [5]俄罗斯科学院新西伯利亚分院梅尔尼科夫冻土研究所,俄罗斯雅库茨克 [6]雅砻江水电开发有限公司,四川成都610051

出　　处：《岩土力学》2021年第1期86-92,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(No.41771078);国家自然科学基金委员会(NSFC)与俄罗斯基础研究基金会(RFBR)合作交流项目(No.42011530083);雅砻江流域水电开发有限公司科学技术项目(No.YLLHK-LHA-2019006)。

摘　　要：冻融作用可以改变土的结构,引起其力学特征的变化,从而影响到冻土工程的稳定性。由于冻融周期的设定不尽相同,因此大量的试验结果不能有效地进行对比分析。另外,对于冻融作用下土体力学特征的预测也成为研究的难点。在冻土遗传蠕变理论的基础上,利用球型模板压入仪作为测试方法,提出了一种冻融次数-物理时间比拟的方法。把冻融周期(次数)转化成物理时间(min),将不同冻融周期土的长期强度曲线簇映射到同一坐标中,利用该归一化曲线进行长期抗剪强度的预测,并选取了两种土样进行了测试,分别得到了相关的长期抗剪强度的预测方程。该方法对冻融作用下土体力学行为的成果对比研究以及长期强度的预测有重要的理论意义,对寒区工程稳定性预测分析也具有工程实践价值。Freezing and thawing processes can change the structure of frozen soil and reduce the mechanical properties, thus affecting the stability of engineering infrastructures built in frozen soil. Due to the different settings of freeze-thaw cycles, a large number of experimental results cannot be effectively compared and analyzed. In addition, estimating the soil mechanical characteristics under freeze-thaw action has also become a research difficulty. In this paper, based on the frozen soil genetic creep theory, a spherical indenter is developed, and a freeze-thaw cycle–physical time analogy method is proposed. Using the number of cycles(numbers of freeze-thaw cycles) and the duration time(physical time–minutes), we can obtain the long-term strength curve family of the frozen soil and mapping the curve family into the same stress space to achieve the normalized strength curve, and thus we can predict the long-term deformation and shear strength. Finally, two soil samples are selected for testing, and the relevant equations for predicting the long-term shear strength are obtained. This method has important theoretical significance for the comparative study on the mechanical behavior of frozen soils under freeze-thaw actions. It also has value for engineering practice and stability analysis of infrastructures built in cold regions.

关 键 词：冻融循环 冻土力学 长期抗剪强度 时间比拟法 球型模板压入仪 

分 类 号：TU411[建筑科学—岩土工程]