泥石流排导槽最小不淤纵坡初步试验研究

A Preliminary Experimental Study on Gradient of Debris Flow Drainage Canal

纵坡是泥石流排导槽设计重要参数之一。通过试验研究 ,对 2组粒径级配 ,8种不同容重的泥石流在排导槽内运动最小纵坡进行研究 ,结果表明 :(1)粒径小于 0 .0 5 mm的泥流可以在很小排导坡度下流动 ;同一容重、级配的泥石流 ,随排导槽纵坡减小 ,槽内运动速度逐渐减缓 ,泥深增大 ;(2 )随泥石流容重的增大 ,排泄其所需纵坡将增加 ;泥石流最小不淤纵坡除与容重有关外 ,还与固体物质粒径大小、细颗粒含量等有密切关系。

By using a dynamic experimental devices of debris flow, a series of indoor model tests on debris flow passing through drainage canal are carried out. The shape of cross section of model drainage canal is rectangled with a width of 25 cm. The solid material is take from the Jiangjia ravine of which the gravel's maximum diameter is 40 mm. The test results are as follows: (1) Debris flow of the maximum diameter of <0.05 mm can move on very small gradient of drainage canal; (2) The larger density of debris flow, the larger gradient of drainage is; (3) The gradient of moving debris flows in the drainge are relation with the density of debris flow, gravel's maximum diameter and fine particles.