Mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradation

CORC > 成都山地灾害与环境研究所 > 中国科学院水利部成都山地灾害与环境研究所 > Journal of Mountain Science > Journal of Mountain Science-2016 > Vol13 No.2

	Mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradation
	FAN Xiao-yi; TIAN Shu-jun; ZHANG You-yi
刊名	Journal of Mountain Science
	2016-02
卷号	13 期号:2 页码:234-245
关键词	Granular flow Angle of slope Runout plane Particle size gradation Mass-front velocity Energy-profile
ISSN号	1672-6316
通讯作者	FAN Xiao-yi
英文摘要	The mass-front velocities of granular flows results from the joint action of particle size gradations and the underlying surfaces. However, because of the complexity of friction during flow movement, details such as the slope-toe impedance effects and momentum-transfermechanisms have not been completely explained by theoretical analyses, numerical simulations, or field investigations. To study the mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane andparticle size gradations we conducted model experiments that recorded the motion of rapid and long-runout rockslides or avalanches. Flume tests were conducted usingslope angles of 25°, 35°, 45°, and 55° and three particle size gradations. The resulting mass-front motions consisted of three stages: acceleration, velocity maintenance, and deceleration. The existing methods of velocity prediction could not explain the slowing effect of the slope toe or the momentum-transfer steady velocity stage. When the slope angle increased from 25° to 55°, the mass-front velocities dropped significantly to between 44.4% and 59.6%of the peak velocitiesand energy losses increased from 69.1% to 83.7%of the initial, respectively. The velocity maintenance stages occurred after the slope-toe and mass-front velocity fluctuations. During this stage, travel distances increased as the angles increased, but the average velocity was greatest at 45°.At a slope angle of 45°, as the median particle size increased, energy loss around the slope toe decreased, the efficiency of momentum transfer increased, and the distance of the velocity maintenance stage increased. We presented an improved average velocity formulafor granular flow and a geometrical model of the energy along the flow line.
收录类别	SCI
语种	英语
内容类型	期刊论文
源URL	[http://ir.imde.ac.cn/handle/131551/14070]
专题	成都山地灾害与环境研究所_Journal of Mountain Science _Journal of Mountain Science-2016_Vol13 No.2
推荐引用方式 GB/T 7714	FAN Xiao-yi,TIAN Shu-jun,ZHANG You-yi. Mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradation[J]. Journal of Mountain Science,2016,13(2):234-245.
APA	FAN Xiao-yi,TIAN Shu-jun,&ZHANG You-yi.(2016).Mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradation.Journal of Mountain Science,13(2),234-245.
MLA	FAN Xiao-yi,et al."Mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradation".Journal of Mountain Science 13.2(2016):234-245.