循环荷载下路基压实粉土的临界应力与应变水平

The threshold stress and strain levels of compacted silt under repeated loadings

通过动三轴试验,分析了不同压实系数、不同含水率和不同动应力水平条件下路基压实粉土的累积塑性变形特征、影响因素及演化规律,界定了循环荷载作用下路基压实粉土的临界动应力和动(回弹)应变水平。试验表明,路基压实粉土的临界动应力和动应变水平随压实系数增加而增大,试样含水率越低,变化速率越大;同时随含水率增加而降低,且含水率越高,降低速率越大。此外,还随静强度增加近似线性增大,回归分析得到比例系数分别为0.5204和0.0007。

Through dynamic triaxial tests,the accumulative plastic deformation and its influencing factors,evolution laws of compacted silt in various conditions of compaction coefficient,water content and dynamic stress levels were analyzed,and the threshold stress and strain levels of compacted silt under repeated loading were defined.It is found that the threshold stress and strain levels of compacted silt increase with increasing compaction coefficient,and the lower water content,the greater variation rate;moreover,the threshold stress and strain levels decrease with increasing water content,and the higher water content,the greater reduction rate.In addition,the threshold stress and strain levels increases linearly with the increase of static strength,and regression analysis shows that the proportion factors are 0.5204 and 0.0007,respectively.