循环荷载作用下粉土的动力学特征

选用近海分布广泛的粉土为研究对象,利用动三轴压缩试验结果得到了动荷载作用下粉土的应力-应变关系、孔压发展模式及动强度与临界循环次数之间的关系;探讨固结围压和固结比对粉土动力学性质的影响。动力学试验结果表明,动剪切模量随着固结围压的增大而增大,动阻尼比随动剪应变幅的变化关系受围压影响不大;不同围压对动剪应力的比值影响很小,同一围压下随着固结比的增大,动剪应力比也会随之增大;不同围压及不同固结比对以Nf表示的峰值孔隙水压力发展模式影响很小。

Dynamic Characteristics of Silty Soil Under Cyclic Loadings

In this paper,the silty soil is chosen as the study object,the dynamic triaxial compression test results are used to obtain the relationship between silty soil stress and strain,the pore water pressure deve-(lopment) model and the relationship between dynamic strength and critical number of cyclic times,and the effects of ambient consolidation pressure and consolidation ratio on silty soil dynamic characteristics are explored.It is shown from the dynamic test results that the dynamic shear modulus increases with increasing ambient consolidation pressure,and the variations in dynamic damping ratio with dynamic shear strain range are slightly affected by the ambient consolidation pressure;the dynamic shear stress ratio is slightly affected by the ambient consolidation pressure,and the dynamic shear stress ratio increases with increasing consolidation ratio under the same ambient consolidation pressure;the pore water pressure development model is slightly affected by ambient consolidation pressure and consolidation ratio.