摘要
由于粘性土颗粒间粘结力的作用,使得其具有较强的抗冲性和较高的起动流速,这对河势的演变造成一定的影响。为此,通过粘性土起动试验,分析了淤积固结过程中粘性土的物理参量变化情况,建立了干密度、粘粒含量(粒径)与起动流速之间的关系。结果表明,粘性土的粘聚力随含水率的增大而减小,相同含水率条件下,粘粒含量越高粘聚力越大;起动流速随干密度、粘粒含量的增大而增大,粘性土起动流速受中值粒径的影响,实质上与粘粒含量对起动流速的作用相同。在此基础上分析了粘性土起动流速影响因素,提出了起动流速经验公式。研究结果为进一步分析粘性土层对河势演变的影响奠定了基础。
Cohesive soil has stronger impact resistance and higher incipient velocity due to the cohesive force between particles,which has a certain impact on the evolution of river regime.Based on the incipient test of cohesive soil,the change of physical parameters of cohesive soil during the consolidation process is analyzed,and the relationship between dry density,cohesive particle content(particle size)and incipient velocity is established.The results show that the cohesion of cohesive soil decreases with the increase of water content.Under the same water content,the higher the cohesive particle content,the greater the cohesion is.The incipient velocity increases with the increase of dry density and cohesive particle content.The incipient velocity of cohesive soil is affected by the median particle size,which is essentially the effect of cohesive particle content on the incipient velocity.The influencing factors of incipient velocity of cohesive soil are analyzed,and the empirical formula of incipient velocity is put forward.This study lays a foundation for further analysis of the influence of clay layer on river regime evolution.
作者
许琳娟
赵万杰
李军华
江恩慧
宋永嘉
XU Lin-juan;ZHAO Wan-jie;LI Jun-hua;JIANG En-hui;SONG Yong-jia(Yellow River Institute of Hydraulic Research,Yellow River Conservancy Commission,Zhengzhou 450003,China;Department of Hydraulic Engineering,Tsinghua University,Beijing 100084,Chin;State Key Laboratory of Hydro-Science and Engineering,Tsinghua University,Beijing 100084,China;North China University of Water Resources and Electric Power,Zhengzhou 450046,China)
出处
《水电能源科学》
北大核心
2020年第3期121-124,128,共5页
Water Resources and Power
基金
国家自然科学基金项目(51709123)
中央级公益性科研院所基本科研业务费项目(HKY-JBYW-2018-03)。
关键词
粘性土
干密度
粘粒含量
起动流速
cohesive soil
dry density
cohesive particle content
incipient velocity
作者简介
许琳娟(1984-),女,博士、工程师,研究方向为泥沙运动力学及河床演变学,E-mail:xlj2112003@163.com。
