WANG Yan-gui 1, KUANG Shang-fu 1, 2

1. International Research & Training Center on Erosion and Sedimentation, Beijing 100048, China;
2. China Institute of Water Resources and Hydropower Research, Beijing 100038, China

Abstracts: Falling failure is one of the typical bank failures. In order to understand the collapse process and condition of the falling failures, through analyzing collapse characteristics of the falling failure for the three kinds of banks with the homogeneity, the dualistic structure and the sandy layer, the collapse mechanism and process of the falling failures are studied based on water and sediment movement principle, stability theory of bank and caving erosion experiment with flume. The critical caving erosion width (CCEW) formulas for the shear and toppling failures of simple slope bank were derived in this paper, which was tested using experimental data collected in laboratory with a great agreement. The caving erosion at the bottom of the bank will result in the upper part in the suspended state, and when the caving erosion width is larger than a certain value, the falling failures will occur. The CCEW is depended on soil property of bank, caving erosion position, slope bank form and the crack depth, and increases as the bank height and soil cohesion increase, and decreases as the crack depth on the bank surface and the slope angle of the bank increase.

Key words: typical structure bank; bank base eroding; falling failure; stability coefficient; critical caving erosion width

Published in: Journal of Hydraulic Engineering, Vol. 45, No. 7, 2014