南京航空航天大学学报(英文版)2021,Vol.38Issue(1):44-56,13.
初始静剪应力和颗粒形状对南京砂液化特性的影响
Effects of Initial Static Shear Stress and Grain Shape on Liquefaction of Saturated Nanjing Sand
摘要
Abstract
This paper mainly investigates the effects of initial static shear stress and grain shape on the liquefaction induced large deformation of saturated sand under torsional shear. Nanjing sand,mainly composed of platy grains,is tested with different initial static shear stress ratio(SSR)using a hollow column torsional shear apparatus. The tests find that the saturated Nanjing sand reaches full liquefaction under the superposition of initial static shear stress and cyclic stress for both stress reversal and non-reversal cases. However,it requires a large number of loading cycles to reach full liquefaction if stress reversal does not occur. With increasing the initial static stress,the large deformation of the Nanjing sand should mainly induced by the cyclic liquefaction firstly under a smaller initial shear stress,and then it should be induced by the residual deformation failure. The critical point occurs approximately when the initial shear stress is close to the amplitude of the cyclic shear stress. Meanwhile,it shows that grain angularity increases the liquefaction resistance when the initial static shear stress is zero. A small initial static shear stress causes the larger loss of liquefaction resistance for angular sand than rounded sand. At a high initial SSR,the angular sand is more resistant to the large residual deformation failure than the rounded sand.关键词
南京砂/砂土液化/初始剪应力/颗粒形状/累积变形破坏Key words
Nanjing sand/liquefaction/initial shear stress/grain shape/residual deformation failure分类
建筑与水利引用本文复制引用
庄海洋,潘书轩,刘启菲,于旭..初始静剪应力和颗粒形状对南京砂液化特性的影响[J].南京航空航天大学学报(英文版),2021,38(1):44-56,13.基金项目
This work was supported by the Na?tional Natural Science Foundation of China(Nos.51778290,51778386),the National Science Fund for Dis?tinguished Young Scholars(No.51725802),and the Natu?ral Science Foundation of Jiangsu High School(No.16KJA560001). (Nos.51778290,51778386)