饱和砂土试样的初始各向异性研究

利用装配了全表面变形数字图像测量系统的静三轴仪,针对不同密实度的饱和大连河砂和南海钙质砂,在各向等压加载条件下,研究了采用不同制样方法制备的试样初始各向异性的差异,并考虑了试样尺寸效应的影响。同时,利用真三轴仪进行横向对比试验,验证采用全表面变形数字图像测量系统获得结果的可靠性。试验结果表明:不同制样方法制备的同一种砂土表现初始各向异性的差异;采用相同的制样方法制备的不同砂土,因颗粒性状的差异,也表现出不同的初始各向异性性质。

Research on Inherent Anisotropy of Saturated Sand Sample

Samples of Dalian river sand and calcareous sand in the South China Sea were prepared in various densities through different sampling methods to study the difference of inherent anisotropy. The triaxial apparatus assembled with whole-surface digital image measuring system was adopted in the test. The influence of sample size effect under the condition of confining pressure was also considered. The reliability of the whole-surface digital image measuring system was verified by comparing with true triaxial apparatus. The test results show that the character of inherent anisotropy is different for the same sand made by different sampling methods. The inherent anisotropy of different sands made by the same sampling method also shows a difference because of their unique grain composition.