糙率是泥石流防治工程重要设计参数之一,糙率大小直接影响残留层阻力大小.为研究残留层减阻机理,通过40组蛋清试验模拟黏性残留层,观察玻璃球在其上的运动,探讨黏性残留层减阻作用与糙率的关系. 在试验数据的基础上,分析残留层糙率与残留层厚度、密度和斜坡坡度的关系,并得出结论: 糙率与残留层厚度、密度成正比关系,与斜坡坡度成反比关系.

Roughness is an important design parameter of debris flow control engineering and it directly affects the resistance strength of the residual layer. To study the residual layer drag reduction mechanism,we simulated viscous residual layer by performing 40 groups of egg white tests. The glass ball motion on the viscous residual layer was observed and the relationship between resistance reduction of the viscous residual layer and roughness was studied. On the basis of the experimental data,the relationships of roughness with residual layer thickness,density,and slope gradient were analyzed,and the conclusions are given as follows. Roughness is proportional to the residual layer thickness and density and it is inversely proportional to the slope gradient. These results provide a theoretical basis for the future design of debris flow control project.