酸性环境下Q_(2)黄土一维固结蠕变特性

One-Dimensional Consolidation Creep Test of Acid-contaminated Q Loess

为探究酸污染对Q_(2)黄土的固结蠕变力学特性的影响,利用高压固结仪对污染试样进行不同竖向应力水平下的一维固结蠕变试验,分析一维固结状态下0.5mol/L、1.0mol/L、2.0mol/L的盐酸浓度变化对黄土应力-蠕变变形量的影响规律。以受酸污染的黄土试样固结蠕变数据为依据,验证了Burgers蠕变模型在描述酸污染黄土应变时间关系上的适用性。研究结果表明:随着酸液浓度的增加,酸蚀黄土的蠕变变形量也逐渐增大,且在高应力作用下,增加量越大;Burgers模型可以较好地描述酸蚀黄土一维固结状态下的衰减蠕变特性,模型简单,适用性强;经酸液侵蚀的黄土,在同一酸液浓度下,高应力作用对Maxwell体弹性模量Em、黏滞系数ηm和Kelvin体弹性模量Ek有提高作用,随着酸液浓度的增大此三参数数值呈现减小趋势;酸污染对黄土流变特性产生劣化效应,黄土流变性能增强。研究结果可为酸污染土地区环境岩土工程流变问题提供参考。

In order to explore the effect of acid pollution on the consolidation creep mechanical properties of Q_(2) loess,a high-pressure consolidation instrument is used to conduct a one-dimensional consolidation creep test at different vertical stress levels on the contaminated samples to analyze the influence of 0.5 mol/L,1.0 mol/L,2.0 mol/L hydrochloric acid concentration changes on the stress-creep deformation of loess under one-dimensional consolidation.Based on the consolidated creep data of the acidcontaminated loess samples,the Burgers creep model is verified to describe the acid-contaminated loess applicability in relation to strain time.The results show that with the increase of acid concentration,the creep deformation of acid-etched loess gradually increases,and under high stress,the increase is greater;the Burgers model can better describe the one-dimensional consolidation of acid-etched loess,the attenuation creep characteristics under the state are simple,and the applicability is strong;for the loess eroded by the acid solution,under the same acid solution concentration,the high stress action on the Maxwell body elastic modulus Em,the viscosity coefficientηm,and the Kelvin body elastic modulus Ekhas an increasing effect,and as the concentration of acid increases,the values of these three parameters decrease.Acid pollution has a deteriorating effect on the rheological properties of loess,and the rheological properties of loess are enhanced.The results can provide some reference for the rheological problems of environmental and geotechnical engineering in acid-polluted land areas.