考虑温度影响的非关联弹塑性饱和黏土本构模型

刘红 陈琴梅 卢黎 肖杨 吴焕然

摘要：從不同温度作用下的压缩曲线和回弹曲线出发，利用等效的力学固结代替热固结，将常规温控三轴试验过程中复杂的热力学特性转化为纯力学特性，然后结合传统的临界状态理论，运用非关联流动法则，提出考虑温度影响，适用于正常固结饱和黏土的非关联弹塑性本构模型。模型包含6个独立参数，各参数的物理意义明确，且可由常规的温控三轴实验确定。随着温度的增加，压缩曲线和回弹曲线的斜率、临界应力比和泊松比不变，先期固结应力呈指数形式变化，此外，塑性势函数和屈服函数之间的比例因子可通过试算确定。结合高岭土和伯克土的常规温控三轴排水剪切试验数据，给出了模型参数的具体确定方法，并将模拟值和试验值进行对比，验证了该模型的合理性。

关键词：饱和黏土;压缩曲线;回弹曲线;弹塑性模型;温度影响

中图分类号：TU431 文献标志码：A 文章编号：20966717（2020）04005307

收稿日期：20191225

基金项目：国家自然科学基金（No. 51678094）;内江师范学院科研资助项目（YLZY201907）

作者简介：刘红（1987 ），女，博士，主要从事土体热力学特性试验与理论研究，Email：cqulhong@163.com。

肖杨（通信作者），男，教授，博士生导师，Email：hhuxyanson@163.com。

Received：20191225

Foundation items：National Natural Science Foundation of China （No. 51678094）; Scientific Research Funding Project of Neijiang Normal University （YLZY201907）

Author brief：Liu Hong（1987 ）， PhD， main research interests： experiment and theory of soil thermodynamic properties， Email：cqulhong@163.com.

Xiao Yang （corresponding author）， professor， doctorial supervisor， Email： hhuxyanson@163.com.

Temperaturedependent nonassociated elasticplastic consititutive model for saturated clay

Liu Hong1， 2， Chen Qinmei1， Lu Li2， Xiao Yang2， Wu Huanran2

（1.College of Architectural Engineering， Neijiang Normal University， Neijiang 641100， Sichuan， P.R. China;2.Key Laboratory of New Technology for Construction of Cities in Mountain Area of Ministry of Education， Chongqing University， Chongqing 400045， P.R. China）

Abstract： Based on the compression and swelling curves at different temperatures， the thermal consolidation phase is substituted by a mechanical consolidation phase， which is of the same deformation. Then， the complex thermomechanical properties of soils have been translated into pure mechanical properties. Further， a new nonassociated elasticplastic consititutive model considering temperature effects is presented by using the traditional critical state theory and nonassociated flow rule. The whole model contains six independent parameters， and the physical significance of each parameter is specific and easy to be confirmed through the temperaturecontrolled triaxial compression test. In addition， with an increase in temperature， the slopes of the compression and swelling curves， the critical state stress ratio and poison ratio have no obvious changes， while the preconsolidation pressure changes exponentially. Otherwise， the trial method is used to determine the scaling factor between the plastic potential and yield equations. Finally， the method of determining each model parameter is put forward in detail on account of the drained temperaturecontrolled triaxial test for Kaolin and Bourke clays， and the new model is proved to be reasonable by comparing the simulation values and test data.

Keywords：saturated clay; compression curve; swelling curve; elasticplastic model; temperature effects