不同级配组成对泥沙流变特性影响实验研究  

Experimental study on the influence of silt content on sediment rheological properties

作　　者：麻考 许春阳[1,2] 陈永平 周春艳[2] MA Kao;XU Chun-yang;CHEN Yong-ping;ZHOU Chun-yan(Jiangsu Key Laboratory of Coast Ocean Resources Development and Environment Security,Hohai University,Nanjing 210024,China;College of Harbor,Coastal and Offshore Engineering,Hohai University,Nanjing 210024,China)

机构地区：[1]河海大学江苏省海岸海洋资源开发与环境安全重点实验室,江苏南京210024 [2]河海大学港口海岸与近海工程学院,江苏南京210024

出　　处：《泥沙研究》2024年第2期25-32,共8页Journal of Sediment Research

基　　金：国家重点研发计划项目(2023YFC3008100);国家自然科学基金项目(42376171);中央高校基本科研业务费专项资金转助(B230201047)。

摘　　要：针对江苏沿海条子泥区域泥沙,运用控制剪切速率实验方法,通过改变样品中的粉沙质量占比,系统探究了泥沙的级配对其剪切应力和黏度的影响规律,并使用剪切速率扫描法和间接法分别计算泥沙样品静态和动态屈服应力。结果表明:所有组次泥沙样品均表现出两次明显的屈服行为,其流变特性以两个屈服行为为界,划分为3个阶段;泥沙样品中粉沙含量对其流变特性起着关键性作用,粉沙含量增大,样品剪切应力和黏度均发生相应减小,其中粉沙含量在35%~55%区间内变化梯度较大,此区间可能存在泥沙粒间主导作用力的转变;最后依托剪切速率扫描法测得的实验数据分析,得到了不同粉沙含量下泥沙的静态屈服应力和动态屈服应力的经验公式。A series of experiments were conducted to investigate the effects of silt content on the rheological properties of sediment collected from Jiangsu coast.The static and dynamic yield stresses of sediment samples were calculated by shear rate scanning method and indirect method respectively.The results show that two yield points for all the sediment samples occur with the increase of shear rate.Therefore,the rheological properties(i.e.the shear stress against shear rate)can be divided into three stages based on the two yield points.The silt content in the sediment sample plays a key role in its rheological properties.With the increase of silt content in the sediment,the shear stress and viscosity decrease accordingly,with a significant gradient as the silt content is in the range of 35%~55%,which may indicate a transition in the dominant force between sediment particles.Finally,based on the experimental data measured by shear rate scanning method,the empirical formulas of static yield stress and dynamic yield stress under different silt content are proposed.

关 键 词：粉沙含量 剪切应力 黏度 屈服应力 

分 类 号：TV141.1[水利工程—水力学及河流动力学]