盐溶液饱和黏土的等向压缩特性  

Isotropic compression characteristics of clayey soil saturated by salty solution

作　　者：颜荣涛[1] 赵续月 于明波[1] 韦昌富[1] 

机构地区：[1]桂林理工大学土木与建筑工程学院,广西桂林541004

出　　处：《岩土力学》2018年第1期129-138,共10页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(No.11562007;No.51309055;No.11372078);广西自然科学基金项目(No.2014GXNSFBA118236)~~

摘　　要：利用不同浓度Na Cl溶液饱和黏土,进行等向压缩试验并分析渗透吸力对等向压缩特性的影响规律。试验结果表明:渗透吸力对于黏土的等向压缩行为存在明显影响,主要体现在对初始弹性压缩线斜率、初始屈服应力的影响上。随着渗透吸力的增大,初始弹性压缩线斜率增大、初始屈服应力逐渐减小;而渗透吸力对弹塑段压缩线斜率和卸荷回弹线斜率影响不大。基于等向压缩试验结果,建立了盐溶液饱和黏土的本构模型,经过验证该模型能有效地模拟盐溶液饱和黏土的等向压缩特性。此外,该模型还可以模拟恒定等向压力下渗透吸力改变引起的试样变形。该等向压缩试验结果及所建立的模型为进一步分析及模拟化学-力学耦合行为提供了数据支持和理论基础。In this paper, isotropic compression tests on clayey soil with pore water of different salt concentrations were carried out. Meanwhile, the testing results were used to analyze the effect of osmotic suction on compressibility. According to the experimental results, isotropic deformation characteristics were significantly influenced by osmotic suction. As osmotic suction increases, the slope of initial elastic compression line increases and stress decreases, while the effect of osmotic suction on the slopes of elasto-plastic compression lines and swelling lines can be neglected. Based upon the experimental results, a constitutive model considering in-pore salty solution influence for clayey soil is proposed under isotropic condition. Through the verification, the model is valid for simulation of isotropic compression behavior. Additionally, the proposed model could be adopted to simulate the response of saturated soil with salty solution to the change in osmotic suction. The experimental result is of vital importance to develop a constitutive model considering chemical-mechanical coupling.

关 键 词：黏土 NACL溶液 等向压缩 本构模拟 

分 类 号：TU411[建筑科学—岩土工程]