关键词: 路基工程, 动态回弹模量, 水泥改良高液限黏土, 动三轴试验, 应力依赖, 预估模型

Abstract: In order to investigate the factors which affect the cement improved high liquid limit clay dynamic resilient modulus and their variation laws, a series of dynamic resilient modulus tests were carried out by conducting dynamic-triaxial tests. The study demonstrated that dynamic resilient modulus values rise with the increase of confining stress, compaction degree and cement content, decrease with the increase of circular deviator stress and moisture content. To accomplish the purpose of analysis the relationships between deviator stress, bulk stress and dynamic resilient modulus, the dual-factor analysis of variance was utilized. The analysis demonstrated that both the deviator stress and bulk stress have significant effects on the dynamic resilient modulus. However, the deviator stress has more significant effects. Considering that dynamic resilient modulus is a function of deviator stress and bulk stress, with a brief analysis of adaptability of the present dynamic resilient modulus constitutive models, the three-parameters compound constitutive model which reflects the effect of bulk stress and deviator stress was utilized for experimental data regression analysis. A high coefficient of determination shows that the model which reflects the effect of bulk stress and deviator stress is accurate and credible. The prediction models used for different compaction degrees, moisture contents and cement contents were achieved; and they can provide parameters for the pavement design based on dynamic method.

Key words: subgrade engineering, dynamic resilient modulus, cement improved high liquid limit clay, dynamic triaxial test, stress dependent, prediction model