Abstract: Flushing sluice is a hydraulic structure for transporting silt of upper stream of the river or the canal using the fast water flow. The cracks are often encountered at the bottom slab and caisson of the lock structure. The propagation of these cracks in the relative integral area, cracked region and recovered strength conditions are analyzed by nonlinear finite element method. Research conclusions can be obtained throughout the statistical summary of the volume of elements with open cracks, the analysis of the sensitivity of the recovered strength as well as the comparative study of the stress ratio of the cracked area. The results show that, when the material strength of the cracked region recovers to 50% of recovered strength, the volume of the cracked elements will not change, and the stress state has basically returned to the fully recovered state and the safe operation of flushing sluice can then be assured.

Key words: Flushing Sluice, Cracks, Nonlinear Finite Element Method, Recovery, Cracked Element