Abstract: On the base of un-drained dynamic tri-axial shearing tests，soil-rock ratio，confined pressure and earthquake intensity influence on the dynamic properties of the soil-rock medium are researched． The change rule of the dynamic strength is mainly studied，and the change rules of the dynamic cohesion as well as the dynamic internal friction angle of the dynamic strength parameter are also analyzed． The research shows that the dynamic strength of the soil-rock medium increases with the decrease of soil gravel ratios and decreases obviously with the increase of seismic intensity under the condition of the same compaction; the dynamic cohesion decreases gradually with the increase of intensity; while the dynamic internal friction angle decreases with the increase of intensity for a certain stones content，the dynamic cohesion and the dynamic internal friction angle increases with the decrease of soil gravel ratios under the condition of same intensity． Finally，the empirical model of the dynamic cohesion and the dynamic internal friction angle，which is changing with the variation of the soilrock ratio and the earthquake intensity，is given．

Key words: soil-rock mediums, dynamic strength, earthquake intensity, experimental research

摘要： 基于室内不排水动三轴试验，研究了土石比、围压和地震烈度对土石复合介质的动力特性的影响| 针对动强度 的变化规律，分析了动强度参数动黏聚力和动内摩擦角的变化规律。研究表明: 在相同压实度条件下，土石复合介 质的动强度随土石比的减小而增大，随地震烈度的提高明显减小| 对某一含石量，动黏聚力随烈度的增大逐渐减小， 并且随土石比减小减小得更快，而动内摩擦角随烈度的增大而减小| 在烈度相同，即相同振次条件下，动黏聚力随土 石比减小而增大，动内摩擦角也随土石比减小而增大。最后，给出了动黏聚力和动内摩擦角随土石比和烈度变化的 经验模型。

关键词: 土石复合介质, 动强度, 烈度, 试验研究