摘要
根据坡面风沙受力情况,以滚动模式建立了坡面风沙起动的风速公式.计算分析了相同风向条件下不同坡度风沙的起动风速和相同坡度条件下不同风向风沙的起动风速,并与平面风沙起动计算风速和实测风速进行了比较.计算分析表明,在风向一定时,坡面风沙更容易起动,风沙起动速率随着坡度的变陡而变小.在坡度一定时,风沙起动风速受到风向的影响很大,起动风速随风力与水平面垂线夹角的增大而增大.与平面相比,当风力与水平面垂线夹角小于90°时,坡面风沙起动流速比平面为小.在当风力与水平面垂线夹角大于90°时,起动风速比平面为大.当坡面为平面时,风沙起动公式与平面拜格诺起动公式完全一致.
Based on the force acting on the wind-blown sediment over the slope, a formula for the threshold velocity is derived. The threshold wind velocity for different slope angles in the same wind direction and for different wind directions at same slope angle are calculated. They are compared with the threshold wind velocity at 0° slope angle. The results show that in the same wind direction, the threshold wind velocity over a slope is smaller than that on a plane. The threshold wind velocity on a slope varies with the wind direction. When the slope angle is zero, the formula is identical to the Bagnold formula.
出处
《力学与实践》
CSCD
北大核心
2003年第5期14-17,共4页
Mechanics in Engineering
基金
长江三峡工程泥沙问题"九五"项目(95-5-4)
黄河上中游管理局项目(96-dd-019)资助.
