黄河宁蒙河段黄土蠕变特性与分数阶本构模型研究  

Study on Creep Characteristics and Fractional Constitutive Model of Loess in the Ningmeng River Reach of Yellow River

作　　者：许旭兵 张帆 侯佼建 张敏[1] 杨浩明[1] 董成会 XU Xubing;ZHANG Fan;HOU Jiaojian;ZHANG Min;YANG Haoming;DONG Chenghui(Yellow River Institute of Hydraulic Research,Yellow River Conservancy Commission,Zhengzhou 450003,China;Civil Engineering College,Tongji University,Shanghai 200092,China;Henan Xinhua Wuyue Pumped Storage Power Generation Co.,Ltd.,Xinyang 465450,China)

机构地区：[1]黄河水利委员会黄河水利科学研究院,河南郑州450003 [2]同济大学土木工程学院,上海200092 [3]河南新华五岳抽水蓄能发电有限公司,河南信阳465450

出　　处：《华北水利水电大学学报（自然科学版）》2023年第3期61-68,共8页Journal of North China University of Water Resources and Electric Power：Natural Science Edition

基　　金：黄河水利科学研究院科技发展基金专项(黄科发202007);引江济淮工程(河南段)工程科研服务项目(HNYJJH/JS/FWKY-2021001)。

摘　　要：黄河宁蒙河段渠堤、土石坝、大型水闸等水利工程构筑物地基在长期荷载作用下会因黄土蠕变产生沉降,进而对水利工程前期建设以及后期的安全运行及维护造成不利影响。因此,对黄土蠕变特性进行研究,揭示其蠕变机理,建立黄土蠕变本构模型具有重要意义。本文以宁蒙河段黄土为研究对象,利用三轴流变仪对宁蒙河段黄土进行一系列的三轴固结排水蠕变试验,基于分数阶导数理论对黄土蠕变变形进行分析。通过数值模拟对试验结果进行验证,并将黄土分数阶蠕变模型运用到黄土地基沉降预测中。研究结果表明:宁蒙河段黄土具有典型的蠕变特性,总体呈非线性衰减蠕变;围压和偏应力对其蠕变特性具有显著影响;分数阶蠕变模型能够很好地描述黄土瞬时弹性变形、衰减蠕变和稳态蠕变3个阶段的变化情况。The foundation of hydraulic engineering structures such as canal embankments,earth-rock dams,and large water gates in the Ningmeng River section of Yellow River may experience settlement due to loess creep under long-term load,which may have adverse effects on the early stage of hydraulic engineering construction and the safe operation and maintenance in the later stage.Therefore,it is of great significance to study the creep characteristics of loess,reveal its creep mechanism,and establish a constitutive model for loess creep.In this paper,the loess in the Ningmeng River section is taken as the research object,and a series of triaxial consolidation drainage creep tests are carried out on the loess in the Ningmeng River section by using a triaxial rheometer.Based on the theory of fractional derivative,the creep deformation of loess is analyzed,and numerical simulations are conducted to verify the experiment.The fractional creep model of loess is applied to predict the settlement of loess foundation.The results are as follows.The loess in the Ningmeng River section has typical creep characteristics,and generally exhibits nonlinear attenuation creep.The confining pressure and deviatoric stress have a significant impact on creep characteristics.The fractional order creep model can accurately describe the changes in the instantaneous elastic deformation,attenuation creep,and steady-state creep stages of loess.

关 键 词：黄土 蠕变 三轴试验 分数阶本构模型 数值模拟 

分 类 号：TV16[水利工程]