砂土动应力-应变发展特性试验  

Test of Sand Dynamic Stress-strain Behavior

作　　者：许成顺[1,2] 栾茂田[3] 郭莹[3] 

机构地区：[1]北京工业大学城市与工程安全减灾省部共建教育部重点实验室 [2]大连理工大学土木水利学院岩土工程研究所,大连116023 [3]大连理工大学土木水利学院岩土工程研究所

出　　处：《北京工业大学学报》2008年第9期956-960,共5页Journal of Beijing University of Technology

基　　金：北京市属市管高校人才强教计划资助项目(05004012200515);国家自然科学基金(50179006).

摘　　要：对福建标准砂和南沙群岛珊瑚砂进行了不同初始固结条件下的循环剪切试验.试验结果表明,在不同固结条件下动应力-应变发展模式显著不同.在均等固结条件下,动应力-应变关系的循环效应和对称累积特性均十分显著,随着砂土强度的完全丧失累积变形迅速发展;而在非均等固结条件下,当动应力作用平面上具有扭剪应力预剪作用时,剪应变则以单向累积变形为主,当动应力作用平面上只有轴向应力作用时,剪应变循环效应相对较大,累积变形并不显著,即使在循环扭剪荷载作用下,变形仍以轴向变形为主.这种特征似乎与中主应力系数没有显著的依赖关系.In this paper, cyclic shear test under different initial consolidation condition are carried for Fujian standard sand and Nansha Islands coral sand. The results indicate that the dynamic stress-strain＇s development mode obviously different in different consolidation. Under isotropic consolidation, the cyclical effect and symmetrical accumulated character of dynamic stress-strain relations are both obvious. And finally, accumulated deformation develop rapidly as loss of sand strength. Under un-isotropic consolidation, when torsion shear stress work on dynamic stress plane in advance, shear strain is mainly mono-directional accumulated deformation; when only axial stress work on dynamic stress plane, shear strain cyclical effect is larger comparatively and accumulated deformation is not obvious. So even under cyclic torsion shear loading, axial deformation is still the main deformation. The property has no obvious dependent relations with principal stress coefficient.

关 键 词：循环扭剪 累积特征 动应力-应变关系 孔隙水压力 

分 类 号：TU411[建筑科学—岩土工程]