压实红黏土三轴蠕变特性试验及模型研究  

Research on Triaxial Creep Characteristics Test and Models of Compacted Red Clay

作　　者：杨果岳 徐运龙[1,2] 李良吉 孙希望 屈畅姿 Yang Guoyue;Xu Yunlong;Li Liangji;Sun Xiwang;Qu Changzi(College of Civil Engineering and Mechanics,Xiangtan University,Xiangtan,Hunan 411105,P.R.China;HunanKey Laboratory of Geomechanics and Engineering Safety,Xiangtan University,Xiangtant Hunan 411105,P.R.China;CreecKunming Survey and Design Institute Co.,Ltd.,Kunming 650000,P.R.China)

机构地区：[1]湘潭大学岩土力学与工程安全湖南省重点实验室,湖南湘潭411105 [2]湘潭大学土木工程与力学学院,湖南湘潭411105 [3]中铁二院昆明勘察设计研究院有限公司,昆明650000

出　　处：《地下空间与工程学报》2019年第3期727-735,共9页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基金(51508489)

摘　　要：利用SLB-1型应力应变控制式三轴剪切渗透试验仪对中石油云南石化铁路专用线高填方路基的压实红黏土进行了一系列三轴蠕变试验,着重研究了压实红黏土在不同围压、不同应力水平以及不同排水条件下的蠕变特性。结果表明:围压、应力水平和排水条件对压实红黏土的蠕变特性均有显著影响;压实红黏土总体呈现衰减蠕变特征;不排水情况下得到的应力应变等时曲线具有明显的非线性特征,且曲线成一曲线簇,具有“归一化”现象,而在排水情况下则呈一定线性关系;并根据应力应变曲线确定了压实红黏土的长期强度为瞬时强度的0.54~0.72倍。基于不排水蠕变试验数据,建立适合该地区压实红黏土的经验蠕变模型,通过与Burgers模型对比发现,该模型参数少、易获取,且对试验数据拟合效果优于Burgers蠕变模型。A series of triaxial creep tests were performed with stress-strain controlled triaxial permeation apparatus SLB-1 to investigate the behaviors of the compaction red clay from high filled subgrade in CNPC Yunnan petrochemical railway. The tests focused on the creep characteristics of compacted red clay under different confining pressures, different stress levels and different drainage conditions. The results indicate that the compacted red clay in this area has the characteristics of attenuation creep. The creep properties of compacted red clay are significantly affected by confining pressure, stress level and drainage conditions. The stress-strain curves obtained under undrained conditions have obvious non-linear characteristics, and the curve is a curve cluster, which has a normalization phenomenon and a certain linear relationship in the case of drainage. The long-term strength of compacted red clay is 0.54~ 0.72 times the instantaneous strength. Based on the undrained creep test, an experiential creep model suitable for the compacted red clay in the area was established. By comparing with the Burgers model, it is found that the model has less parameters and is easy to obtain. Moreover, the empirical model is better than the Burgers creep model to fit the experimental data.

关 键 词：压实红黏土 三轴蠕变试验 蠕变特性 蠕变模型 

分 类 号：TU446[建筑科学—岩土工程]