利用GDS振动三轴试验系统,针对四川省某尾矿库的尾矿粉质黏土料,基于不同固结条件开展振动三轴试验,研究尾矿粉质黏土在分级循环荷载下的变形特性,基于不同固结条件对尾矿粉质黏土各动力变形特性参数的变化情况进行对比分析.结果表明:当固结围压σ3 和固结比Kc不断变大时,尾矿粉质黏土的各动力变形参数呈现出明显不同变化趋势,阻尼比λ会持续变小,动弹性模量Ed与动剪切模量Gd不断增大;在动应变εd不断增大的过程中,阻尼比λ会相应升高,但动弹性模量Ed与动剪切模量Gd却显著下降,动弹性模量比Ed/Edmax逐渐减小,表明动弹性模量逐渐衰减,且衰减过程呈三段式;固结压力σ3 和固结比Kc的增大可以减缓动弹性模量Ed的衰减.采用沈珠江动本构模型对试验结果进行拟合,获得相关模型参数.
Using the GDS vibration triaxial test system,for the tailings silty clay in a tailings pond in Sichuan Province,a vibration triaxial test was carried out based on different consolidation conditions to study the deformation characteristics of the tailings silty clay under graded cyclic loading.The changes of dynamic deformation characteristic parameters of tailings silty clay under different consolidation conditions were compared and analyzed.The results show that when the consolidation confining pressure σ3 and consolidation ratio Kc increase continuously,the dynamic deformation parameters of tailings silty clay show obvious different trends,the damping ratio λ will continue to decrease,and the dynamic elastic modulus Ed and the dynamic shear modulus Gd keeps increasing;when the dynamic strain εd increases,the damping ratio λ will increase accordingly,but the dynamic elastic modulus Ed and the dynamic shear modulus Gd decrease significantly.The ratio Ed/Edmax gradually decreases,indicating that the dynamic elastic modulus gradually decays,and the decay process is three-stage;the increase of consolidation pressure σ3 and consolidation ratio Kc can slow down the decay of dynamic elastic modulus Ed.The Shen Zhujiang dynamic constitutive model was used to fit the test results,and the relevant model parameters were obtained.