摘要
利用GDS动三轴系统对温州地区典型饱和软黏土进行一系列恒定围压和变围压不排水循环加载试验,重点分析循环偏应力和循环围压耦合作用对超固结饱和软黏土不排水循环累积变形特性的影响。试验结果表明:不排水条件下,与围压保持恒定,偏应力单独循环剪切相比,循环围压的存在,一定程度上限制了超固结饱和软黏土永久轴向应变的发展。在平均主应力–广义偏应力(p-q)空间,循环偏应力和循环围压耦合应力路径斜率p/q每增加1,永久轴向应变将降低约20.18%。进一步在试验基础上提出考虑超固结比和循环围压影响的永久轴向应变经验公式。
A series of undrained cyclic tests under consfant/variable confining pressures were carried out on typical Wenzhou soft clay by GDS cyclic triaxial apparatus. The coupling effect of cyclic deviatoric stress and cyclic confining pressure on the undrained permanent deformation of overconsolidated saturated soft clay was studied. Under the undrained condition,the cyclic confining pressure was found to limit the development of the permanent axial strain of overconsolidated saturated soft clay to some extent. The permanent axial strain reduced 20.18% if the ratio ofp/q was raised value of 1. On the basis of the experimental results,an empirical formula incorporating the effect of overconsolidation ratio and cyclic confining pressure was proposed to estimate the permanent axial strain in the undrained cyclic tests.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2015年第3期594-600,共7页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金重点项目(51238009)
国家自然科学基金资助项目(51278383
51108414)
关键词
土力学
循环围压
动三轴试验
超固结黏土
永久轴向应变
soil mechanics
cyclic confining pressure(CCP)
dynamic triaxial test
overconsolidated clay
permanent axial strain
