Effect of variable confining pressure on cyclic behaviour of granular soil under triaxial tests
Effect of variable confining pressure on cyclic behaviour of granular soil under triaxial tests
复制标题
三轴试验下变围压对粒状土循环行为的影响
DOI：
10.1139/cgj-2016-0439
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发表时间：
2017-06-01
影响因子：
3.6
通讯作者：
Wang, Jun
中科院分区：
文献类型：
--
作者：
Sun, Qi;Cai, Yuanqiang;Wang, Jun
以往的研究是利用循环偏应力和围压的组合来模拟交通荷载下的循环竖向和水平正应力。研究了变围压对土体永久变形的影响。然而，一些研究认为，与恒定围压（CCP）试验相比，VCP可以促进永久变形的发展，而另一些则得出相反的结论。在这项研究中，三种类型的CCP和VCP测试具有相同的最大应力，相同的平均应力，和相同的初始应力进行。试验结果表明，当CCP和VCP试验的最大应力或平均应力相同时，VCP试验积累的永久应变更多，且永久应变随应力路径倾角的减小而增大;当CCP和VCP试验的初始应力相同时，产生的永久应变相近。此外，在CCP和VCP试验中，随着应力比或应力路径长度的增加，产生更大的永久应变。考虑到在相同应力比下CCP和VCP试验累积的应变不同，建议在评定永久变形时应同时考虑应力比和应力路径长度。
Previous studies were performed to use combined cyclic deviatoric stress and confining pressure to simulate cyclic vertical and horizontal normal stresses under traffic loading. The effect of variable confining pressure (VCP) on the permanent deformation of soils was investigated. However, some studies concluded VCP could promote the development of permanent deformation compared to the tests with constant confining pressure (CCP), while others drew the opposite conclusions. In this study, three types of CCP and VCP tests with identical maximum stress, identical average stress, and identical initial stress were conducted. Test results showed VCP tests accumulated more permanent strains when CCP and VCP tests had identical maximum or average stress, and the permanent strains increased with the decrease in the inclinations of stress paths, while similar permanent strains were generated when CCP and VCP tests had identical initial stress. In addition, larger permanent strains were generated with the increase in stress ratio or length of stress path in both CCP and VCP tests. Considering that different strains were cumulated in CCP and VCP tests with the same stress ratio, it is recommended that both stress ratio and length of stress path be considered to assess the permanent deformation.