基于南水模型的生物酶改良膨胀土应力–应变关系研究  

Stress-strain characteristics of bioenzyme-treated expansive soil based on SHEN Zhujiang's elasto-plastic model with double yield surfaces

作　　者：文畅平[1,2] 王解军 WEN Changping;WANG Jiejun(Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structural Engineering Materials, Central South University of Forestry and Technology, Changsha, Hunan 410018, China;School of Civil Engineering, Central South University of Forestry and Technology, Changsha, Hunan 410018, China)

机构地区：[1]中南林业科技大学现代木结构工程材制造及应用技术湖南省工程实验室,湖南长沙410018 [2]中南林业科技大学土木工程学院,湖南长沙410018

出　　处：《岩石力学与工程学报》2018年第4期1011-1019,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家国际科技合作专项(2014dfa53120);中南林业科技大学现代木结构工程材制造及应用技术湖南省工程实验室开放基金资助项目(HELFMTS1707);湖南省重点学科建设项目(2013ZDXK006)~~

摘　　要：以生物酶改良膨胀土的双屈服面弹塑性本构关系为研究对象,提出基于生物酶掺量的修正南水模型。通过不同生物酶掺量条件下的重塑膨胀土样的三轴固结排水剪切试验,研究生物酶改良膨胀土的应力–应变关系特征,基于Duncan-Chang模型参数分析方法,分析生物酶掺量对南水模型中相关参数的影响规律。建立南水模型中相关参数与生物酶掺量的相关关系,且基于ε_1-ε_v关系的双曲线特征,对南水模型中的切线体积比u_t确定方法进行修正。修正南水模型中各参数物理意义明确,与南水模型中的参数确定方法一致。对比ε_1-ε_v和q-ε_s的试验曲线和修正南水模型理论计算曲线,修正南水模型可以较合理地描述不同生物酶掺量条件下改良膨胀土的弹塑性应力–应变关系特性,且能反映生物酶掺量对改良膨胀土的弹塑性应力–应变关系的影响。A modified Shen Zhujiang＇s elasto-plastic model with double yield surfaces（Shen＇s model） in terms of the ratio of bioenzyme-based soil stabilizer was presented for the double yield surfaces elasto-plastic constitutive relation of the bioenzyme-treated expansive soil. The triaxial consolidated-drained shear tests of remolded expansive soil samples with the different ratios of bioenzyme-based soil stabilizer were conducted and the stress-strain relationship of bioenzyme-treated expansive soil was studied. The mechanism of the ratio of bioenzyme-based soil stabilizer affecting the relevant parameters in Shen＇s model was analyzed using the parameter analysis method of Duncan-Chang model. The correlation expressions between the parameters of Shen＇s model and the ratio of bioenzyme-based soil stabilizer were put forward and a modified method of tangent volume ratio ut based on the hyperbola relationship of ε_1-ε_v curve was presented. The physical meaning of the parameters of the modified Shen＇s model is well defined,and the test methods for determining the parameters of the modified Shen＇s model are the same as that of the Shen＇s model. The comparison between the experimental curves and the modified Shen＇s model curves of ε_1-ε_v and q-se respectively shows that the modified Shen＇s model describes reasonably the elasto-plastic stress-strain characteristics of expansive soil under the different ratios of bioenzymebased soil stabilizer,and reflects the mechanism of the ratio of bioenzyme-based soil stabilizer in influencing the elasto-plastic stress-strain relationship.

关 键 词：土力学 生物酶改良膨胀土 应力–应变关系 南水模型 双屈服面弹塑性本构模型 三轴试验 

分 类 号：TU411[建筑科学—岩土工程]