基于Lade模型的生物酶改良膨胀土双屈服面本构关系  

Constitutive relation with double yield surfaces of bioenzyme⁃treated expansive soil based on Lade model

作　　者：文畅平 任睆遐 WEN Chang-ping;REN Huan-xia(School of Civil Engineering,Central South University of Forestry and Technology,Changsha 410018,China)

机构地区：[1]中南林业科技大学土木工程学院,长沙410018

出　　处：《吉林大学学报（工学版）》2021年第5期1716-1723,共8页Journal of Jilin University:Engineering and Technology Edition

基　　金：国家国际科技合作专项项目(2014DFA53120);湖南省科技创新计划项目(2020RC4049);湖南省重点学科建设项目(2013ZDXK006).

摘　　要：基于Lade模型,研究了生物酶改良膨胀土的双屈服面弹塑性应力-应变关系。首先,开展一系列不同生物酶掺量下改良膨胀土的等向固结排水试验、三轴固结排水剪切试验;然后,根据试验结果拟合Lade模型中的各参数与生物酶掺量之间的关系表达式;最后,建立基于生物酶掺量的Lade模型。研究表明:①体积应变εv随平均应力p的增大而非线性增大,当p一定时,εv随生物酶掺量增加而减小,εv与p为非线性关系;②轴向应变ε_(1)、侧向应变ε_(3)均随偏应力q的增大而非线性增大,q随生物酶掺量增加而增大,在一定的围压σ3下,εv随生物酶掺量的增加而减小,q-ε_(1)、ε_(1)-εv、q-ε_(3)等试验曲线都呈现出近似双曲线特征,q-ε_(1)关系表现为应变硬化型,体应变εv表现为应变剪缩型;③基于生物酶掺量的Lade模型,能较准确地反映生物酶掺量对膨胀土应力-应变关系的影响,可较好地预测出不同生物酶掺量、不同围压σ3下的生物酶改良膨胀土的弹塑性应力-应变关系。The elasto-plastic stress-strain behaviors with double yield surfaces of bioenzyme-treated expansive soil was studied based on Lade model.Firstly,a series of the isotropic consolidation drainage tests and the triaxial consolidated drained shear tests of bioenzyme-treated expansive soil under different ratio of bioenzyme-based soil stabilizer were conducted.Secondly,the expressions between the parameters of the Lade model and the ratio of bioenzyme-based soil stabilizer were fitted based on the triaxial test results.Finally,a Lade model based on the ratio of bioenzyme-based soil stabilizer was proposed.The study conclusions as follows:①The bulk strainεv increases nonlinear with the average stressp,and decreases with the ratio of bioenzyme-based soil stabilizer at p is constant.The test curves ofεv-pare nonlinear relationship.②The axial strainε_(1),lateral strainε_(3) increases nonlinear with the deviator stress q respectively,and q increases with the ratio of bioenzyme-based soil stabilizer.The bulk strainεv decreases with the ratio of bioenzyme-based soil stabilizer.The test curves of q-ε_(1)、ε_(1)-εv、q-ε_(3) are hyperbola respectively.The stress-strain relationships between q andε_(1) are strain hardening,and the relationships between q andεv are shrinkage.③A Lade model based on the ratio of bioenzyme-based soil stabilizer can better describe the effects of the ratio of bioenzyme-based soil stabilizer on the elasto-plastic stress-strain behavior of bioenzyme-treated expansive soil,and can well predict the stress-strain relationship of bioenzyme-treated expansive soil under different ratio of bioenzyme-based soil stabilizer and confining pressuresσ3.

关 键 词：道路工程 生物酶改良膨胀土 双屈服面本构关系 Lade模型 弹塑性应力-应变关系 

分 类 号：U416.1[交通运输工程—道路与铁道工程]