摘要
利用应力控制式CT-三轴仪及CT-湿陷性三轴仪,在控制吸力的条件下,试验研究原状Q3黄土的浸水湿陷特性。做了2组共15个三轴试验,包括均压浸水试验和以双线法进行的侧向卸荷浸水试验,试验中利用CT机进行无损断面扫描,并用得到的CT数定量分析原状Q3黄土的结构性对湿陷的影响。结果表明:对于双线法湿陷试验,同一吸力和偏应力下,固结净围压大的试样湿陷变形大于固结净围压较小的试样湿陷变形,包括体应变、轴应变及偏应变量;均压浸水湿陷试验时,在试样饱和前,随着浸水量的增加CT数与浸水量之间基本呈线性关系;当试样趋于饱和时,CT数增大减缓;均压浸水湿陷试验中,在同一吸力下,固结净围压大的湿陷体应变较大,结构演化变量值也越大。
The collapsability test for undisturbed Q3 loess under suction control is studied with stress controlled triaxial apparatus.15 CT-triaxial tests are performed,including double-triaxial unloading confining pressure tests and isotropic compression tests.During the tests,computerized tomography(CT) is employed.Using the CT data,the effect of the Q3 loess′s structure is analyzed.The results show that,for the double triaxial collapsible tests,collapsible deformation increases with net confining pressure increasing,including the volumetric strain,axial strain and deviator strain.For the isotropic compression collapse tests,the relationship between water content and the CT data is linear before the specimen is saturated.The CT data increasing velocity will slow down with high enough saturation.For the isotropic compression collapse tests,if the specimen has the same suction,the high net confining pressure versus big volumetric strain,and the value of the structural evolution have the same rule,too.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2010年第6期1288-1296,共9页
Chinese Journal of Rock Mechanics and Engineering