根据拟静力离心试验原理,以沙堆作为散粒体斜坡的概化模型,开展粒径分别为0.5~1.0mm、8.0~10.0mm2种均匀沙和粒径范围为0.25~10.0mm、非均匀系数为3.1的非均匀沙沙堆模型离心试验.试验分别在Ⅴ度、Ⅵ度和Ⅶ度3种不同地震烈度条件下进行,出现了不同的崩塌现象.试验结果表明:粒径为0.5~1.0mm的均匀沙在3种烈度地震作用下的崩塌规模均服从准周期分布;8.0~10.0mm的均匀沙和非均匀系数3.1的非均匀沙在Ⅴ度地震烈度作用下的崩塌规模服从负幂律分布,呈现自组织临界性特征,而在Ⅵ度、Ⅶ地震烈度作用下的崩塌规模服从正态分布.根据试验结果给出了崩塌规律为负幂律分布和正态分布的分布函数.
Based on the principle of pseudo-static method and centrifugal model tests, the laws of avalanches of loose slope are researched by means of the landslips of sand-pile models with one slope,which are used as simplification pattern of granular slopes. This paper reports three centrifugal model tests of uniform sand with size distribution of 0. 5-1.0 mm and 8.0-10. 0 mm, and non-uniform sand with a heterogeneous coefficient 4= 3. 1. From the three centrifugal model tests, three laws of landslips of sand-pile are deduced under earthquake with three magnitudes,i, e. , Ⅴ, Ⅵ and Ⅶ. The test results show that landslips of uniform sand with 0. 5-1.0 mm obey the law of quasi-cyclical distribution under Ⅴ, Ⅵ and Ⅶ ,and landslips of uniform sand with 8. 0-10. 0 mm and non-uniform sand with Ф=3. 1 obey the law of power-law distribution under Ⅴ, presenting self-organlzed criticality, but obey normal distribution under Ⅵ and Ⅶ. Finally,the laws of landslips are indicated by the distillation function.