超固结饱和盐渍黏土化学-力学耦合模型及其验证  

Chemo-mechanical coupling model for overconsolidated saturated saline clay and its validation

作　　者：王立业 周凤玺[1] 牟占霖 万旭升[3] 吴道勇 WANG Liye;ZHOU Fengxi;MU Zhanlin;WAN Xusheng;WU Daoyong(School of Civil Engineering,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan,Ningxia 750021,China;School of Civil Engineering and Geomatics,Southwest Petroleum University,Chengdu,Sichuan 610500,China;Key Laboratory of Karst Geological Resources and Environment,Ministry of Education,Guizhou University,Guiyang,Guizhou 550025,China)

机构地区：[1]兰州理工大学土木工程学院,甘肃兰州730050 [2]宁夏大学土木与水利工程学院,宁夏银川750021 [3]西南石油大学土木工程与测绘学院,四川成都610500 [4]贵州大学喀斯特地质资源与环境教育部重点实验室,贵州贵阳550025

出　　处：《岩石力学与工程学报》2024年第9期2301-2313,共13页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(12362032,11962016);甘肃省重点研发计划——社会发展类(23YFFA0063)。

摘　　要：为了能够准确预测渗透吸力对超固结饱和盐渍黏土力学行为的影响,建立考虑渗透吸力影响的超固结饱和盐渍黏土弹塑性理论模型,为预测饱和盐渍黏土化学-力学耦合行为提供理论依据。该模型是在统一硬化(UH)模型的理论基础上,通过引入渗透效率参数和耦合应力,建立一个同时考虑渗透吸力、固结度和化学-力学耦合效应的统一硬化(UH)模型,并获得超固结比与渗透吸力的理论表达式。结果表明新模型具有如下优势:(1)借助耦合应力的概念可以描述渗透吸力诱发的变形软化和强度硬化效应;(2)在只增加2个参数的基础上就能准确预测不同应力历史、排水条件和含盐条件下饱和盐渍黏土的化学-力学耦合行为;(3)可以揭示饱和盐渍黏土超固结比与渗透吸力的依赖性以及化学-力学耦合行为的作用机制。另外,研究结果为化学环境作用下黏土化学-力学耦合分析及行为预测提供了宝贵的理论基础。To accurately predict the influence of osmotic suction on the mechanical behavior of overconsolidated saturated saline clay,an elastoplastic model considering the effect of osmotic suction is established to provide a theoretical basis for predicting the chemo-mechanical coupling behavior of saturated saline clay.Based on the theoretical foundation of the unified hardening(UH)model,the model is established to consider simultaneously the osmotic suction,degree of consolidation and chemo-mechanical coupling effect by introducing the osmotic efficiency parameter and coupling stress,as well as obtaining the theoretical expressions for the overconsolidation ratio and osmotic suction.From verification results,the new model has the following properties.(1)The effects of deformation softening and strength hardening induced by osmotic suction can be described with the help of the concept of coupled stresses.(2)The chemo-mechanical coupling behavior of saturated saline clay can be accurately predicted for different stress histories,drainage and saline conditions with the addition of only two parameters.(3)The relationship between the overconsolidation ratio of saturated saline clay and osmotic suction can be revealed,as well as the interaction mechanism of their chemo-mechanical coupling behavior.In addition,the results provide a valuable theoretical basis for the chemo-mechanical coupled analysis and behavior prediction of clay under chemical environment.

关 键 词：土力学 饱和盐渍黏土 超固结比 渗透吸力 化学-力学耦合 弹塑性模型 

分 类 号：TU43[建筑科学—岩土工程]