筑坝反滤料动模量和阻尼比影响因素的数值模拟研究

土体动模量和阻尼比是动力学特性的重要表征参数,在工程抗震分析中起到不可或缺的作用。在对动模量和阻尼比试验成功模拟的基础上,改变数值模型中相应的试验条件,探讨了试验中土体动模量和阻尼比的影响因素固结比、围压、试样级配、试样密实度和动应力频率。结果表明:筑坝反滤料的固结比对动模量的影响比较符合Hardin推导公式的结果;最大动模量与围压呈正比;随着密实度的降低,最大动模量亦降低;动应力频率对动模量和阻尼比基本无影响。

Numerical Study of Influencing Factors on Dynamic Shear Modulus and Damping Ratio of Dam Filter

Dynamic shear modulus and damping ratio are important characteristic parameters of soil dynamic property. They play an indispensable role in earthquake resistance research. Through simulating the dynamic shear modulus and damping ratio test by PFC, the influencing factors of dynamic shear modulus and damping ratio of filter, including the consolidation ratio, confining pressure, compactness, graduation and oscillation frequency, were discussed by changing the test condition. Results show that the effect of filter consolidation ratios on maximal shear modulus agrees with the results of Hardin formula. The maximal dynamic shear modulus is proportional to the confining pressure. Dynamic stress frequency nearly has no influence on dynamic shear modulus and damping ratio.