摘要
利用临界状态下的泥沙颗粒受力与休止角的关系建立了非均匀沙的临界平衡方程式,并且以此为基础在假设底部瞬时流速符合正态分布以及对数正态分布的条件下求出了2个起动概率模型。在这2个起动概率模型基础之上推导出了2个非均匀沙的起动流速模型,并且利用现有的实验数据以及野外数据对模型进行了检验。分析表明基于对数正态分布底部流速得到的非均匀沙分级起动流速模型具有比较高的精度。
Based on the relationship between relavent forces acted on particles and the angle of repose at the condition of incipient motion,two pickup probability models were proposed for sediment entrainment under the normally distributed instaneous velocity and lognormally distributed instantaneous velocity,then two incipient velocity for nonuniform sediment models were derived. The results were compared with the published experimental data and field data and the results showed that the mechanism of incipient motion of gravel and cobble which are the main components of mountain river bed may be different from that of sand. The analysis showed that the results for the log-normal distribution reveal a significant improvement of accuracy for the mixtures with or without gravel and cobble.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
北大核心
2013年第5期19-23,共5页
Journal of Sichuan University (Engineering Science Edition)
基金
国家自然科学基金资助项目(51279116
51079090)
教育部博士点基金资助项目(20120181120124)
关键词
起动流速
休止角
非均匀沙
对数正态分布
正态分布
incipient velocity
the angle of repose
non-uniform sediment
log-normal distribution
normal distribution
