重金属污染物CuCl_(2)对粉土边坡稳定性影响研究

Study on the Influence of Heavy Metal Pollutant CuCl_(2)on the Stability of Silt Slope

重金属污染物CuCl_(2)对黄土状粉土边坡整体稳定性具有较大影响。为探究黄土状粉土中CuCl_(2)含量对边坡稳定性的影响,选择污染场地黄土状粉土为研究对象,按CuCl_(2)占黄土状粉土总质量的0%、8%、16%混合配比,将含CuCl_(2)黄土状粉土与水调配成含水率为15%的试样,对试样进行室内直接剪切试验与边坡案例极限平衡计算分析。研究表明:①随CuCl_(2)含量增加,土样抗剪切强度、粘聚力、内摩擦角呈降低趋势,试样在法向应力150 kPa条件下应力-应变曲线呈“S”型,在法向应力100 kPa、50 kPa条件下应力-应变曲线遵循对数曲线关系;②通过对研究区斜坡工程地质详细调查,发现斜坡失稳破坏除受低频强降雨、灌溉、活断层、人类工程扰动等因素影响外,污染物CuCl_(2)对斜坡稳定性影响不容忽视;③理正边坡软件基于极限平衡法-瑞典条分法计算结果显示,随CuCl_(2)含量增加,边坡稳定性系数减小,但CuCl_(2)含量达到10%后,即使继续增加,边坡稳定性系数基本保持不变。

The heavy metal pollutant CuCl_(2)had a great influence on the overall stability of loess-like silt slopes.In order to explore the effect of CuCl_(2)content on slope stability in loess-like silt,this paper selected the loess-like silt of the contaminated site as the research object,and according to the mixed ratio of CuCl_(2)to 0%,8%and 16%of the total mass of loess-like silt,and then the CuCl_(2)-containing loess-like silt was mixed with water into a sample with a moisture content of 15%,and the indoor direct shear test and the limit balance of the slope case were calculated and analyzed.Studies have shown that:①With the increase of CuCl_(2)content,the shear strength,cohesion and internal friction angle of soil samples all showed a decreasing trend,and the stress-strain curve of the specimen was“S”shaped under the normal stress of 150 kPa,and the stress-strain curve followed the logarithmic curve relationship under the normal stress of 100 kPa and 50 kPa;②Through the detailed investigation of slope engineering geology in the study area,it is found that the influence of slope instability and damage on slope stability cannot be ignored,except for factors such as low-frequency heavy rainfall,irrigation,active faults,and human engineering disturbance;③The calculation results of the positive slope software based on the limit equilibrium method-Swedish strip division method show that the slope stability coefficient decreases with the increase of CuCl_(2)content,but after the CuCl_(2)content reaches 10%,even if it continues to increase,the slope stability coefficient remains basically unchanged.