循环荷载作用下低掺量水泥土试样变形性状试验研究

在大量动三轴试验的基础上,深入研究了低掺量水泥土的动力特性。试验结果表明:动应变εd是影响土样动弹模量及阻尼比的最主要因素,随着动应变水平的提高,动弹模量Ed成倍减小而阻尼比λ成倍增大。随着掺灰量的增大,水泥土的动弹模量和阻尼比相应增大。动弹模量随围压σ3增减而增减,阻尼比λ随围压σ3的增加而减小。最大动弹模量Edmax与围压σ3呈指数递增关系;最大阻尼比λmax在7%～30%之间,与围压σ3呈指数递减关系,并建立了相应的经验公式。

DYNAMIC PROPERTIES OF CEMENT TREATED SOFT SOIL FROM TRIAXIAL TEST WITH CYCLIC LOADING

Based on a large amount of dynamic tri-axial tests, dynamic properties of cement treated soft soils are examined thoroughly. The results show that the dynamic strain εd is the most important factor affecting the dynamic modulus and the damping ratio λ. The dynamic modulus Ed decreases and the damping ratio λ increases very rapidly with the increase of the dynamic strain εd. Both the dynamic modulus Ed and the damping ratio λ increase with the increase in the cement dosage ratio. The dynamic modulus increases while the damping ratio decreases as the confining pressure σ3 increases, at the same strain level. It is further found that the maximum dynamic modulus Edmax increases as an exponential function of the confining pressure σ3. The maximum damping ratio λmax varies from 7% to 30% and decreases as an exponential function of the confining pressure σ3. The corresponding formulas are put forward.