二灰改良风积土动力特性试验

在一系列室内动三轴试验的基础上,研究了二灰(石灰、粉煤灰)改良风积土在不同固结围压、固结比、掺灰比和振动频率条件下的动强度特性。通过试验和计算分析,在力学性质较差的风积土中掺入石灰、粉煤灰,其动强度明显提高,且主要表现为动粘聚力增加。其中,尤以掺灰比(石灰∶粉煤灰∶风干土)10∶20∶70,13∶27∶60的石灰粉煤灰土改良效果更为明显,其饱水动强度相对于素土而言提高近2～3倍以上。随着振动频率的升高,二灰改良风积土动剪应力呈现下降的趋势。

Experimental study on dynamic performance for lime-flyash-improved aeolian soil

Based on a series of dynamic triaxial tests,dynamic strength characteristics of lime-flyash-improved soil are researched under the different conditions of confining pressure,consolidation ratio,amount of lime and flyash,frequency of vibration.By means of testing and computational analysis,it shows that dynamic strength of aeolian soil with lime and flyash is obviously improved,mainly for dynamic cohesion.Experiment results show that the improvement effect of lime-flyash soil with the ratio of 10∶20∶70 and 13∶27∶60（lime∶flyash∶air dried soil）is more visible,the saturation dynamic strength of which is improved 2～3 times than that of plain soil.Dynamic shearing strength of lime-flyash-improved soil is decreased along with the improvement of frequency of vibration.