Abstract: The comparing experiment of different influence factors were conducted on the basis of the conceptual model test of various large particle sediment . Thus the movement of large particle sediment were investigated by using photography technology to record the skip trajectory. The results indicated that when the water depth exceeded the critical condition

the sediment will no longer jumping. What’ more

the critical depth increased with the increase of grain diameter

the critical depth approximately equal to the grain diameter. Meanwhile

according to the characteristics of jumping pebble

under a certain grain diameter and gradient

the depth had a negative power function relationship with the saltation height and length. Whereas

under the same depth and gradient

there was a positive power function relationship between jumping height

length and particle size. Besides

when the water depth and particle size are certain

with the increase of gradient

the jumping height decreased

and the jumping length increased. In addition

the jumping length and height had a multiple relations with the particle size and all showed a negative correlations with the water depth and the grain diameter. The experimental conclusions will provide certain reference frame to the design of outlet structures.