【摘要】 利用英国GDS公司研制的空心圆柱扭剪仪,采用应变控制,对琼州海峡海床埋深超过100m的粉质黏土进行动三轴试验,研究有效围压、塑性指数对其动剪切模量Gd和阻尼比的影响。研究发现:在相同条件下塑性指数越大动剪切模量越小,而阻尼比变化规律不明显;根据塑性指数IP、孔隙比e和有效围压σ0’建立了适合计算深层海床粉质黏土最大动剪切模量的经验公式,拟合出模量衰减曲线Gd/Gdmax-γd和阻尼比增长曲线λ-γd的经验公式并给出其上、下包络线拟合参数值。更多还原

【Abstract】 Cyclic triaxial tests controlled by the strain are performed on undisturbed marine silty clay which is located more than 100m depth of The Qiongzhou Strait seabed by the hollow cylinder apparatus made by GDS.Meanwhile,the effects of effective confining pressure and the plastic index IP on the dynamic shear modulus Gd and the damping ratio λ were investigated.It is found that under the same conditions the greater the plastic index is,the smaller dynamic shear modulus are,but the change of damping ratio has no obvious rule.According to the plastic index IP,porosity e and effective confining pressure,an experience formula,which is suitable for calculating the maximum dynamic shear modulus of the deep seabed silty clay,is established.Based on the test results,the fitting parameters of envelope curves of dynamic shear modulus ratio Gd/Gdmaxand damping ratio λ versus dynamic strain γd for deep-sea marine silty clay are presented.更多还原