A New Dam Reliability Analysis Considering Fluid Structure Interaction

Abstract

Gravity dam reliability analysis is inherently complex considering the parameters randomness caused by the spatial variability of dam foundation, the coupled influence of seepage and high nonlinearity of dam safety evaluation. Taking the seepage randomness and dam foundation spatial variability into account, a fluid structure interaction (FSI) stochastic finite element approach and a weighted dynamic response surface method (WD-RSM) are proposed based on the integrated 3D engineering geological model. When applying the methods to gravity dam reliability analysis, three technical issues are considered: (1) the influence of dam foundation spatial variability on the gravity safety, (2) the key effect that the FSI makes on the gravity analysis and (3) the available safety evaluation method for the highly nonlinearity problem. The FSI stochastic finite element approach and the WD-RSM are validated using a real case of a gravity dam in operation with karst foundation. The results show the evident negative effect that seepage militated on the dam stability and the consistency and discreteness that spatial variability of dam foundation incarnated, which facilitates understanding the role of seepage and spatial variability.