Abstract: In the reliability analysis for gravity dam, statistical information is challenging to be obtained by probability reliability analysis due to the limitations posed by uncertain parameters, and the functions are highly nonlinear hence are difficult to be described with analytical expression. In view of this, a non-probabilistic reliability(N-PR) index calculation model of gravity dam in consideration of uncertain parameter ranges is constructed. On this basis,the calculation method of N-PR index for gravity dam in association with Kriging model’s strong prediction and fitting advantages is built.A practical engineering example demonstrates that the present method effectively overcomes the limits that the uncertain parameters shall vary randomly in probability reliability analysis and the calculation results are highly sensitive to the parameters. The method also adapts to the highly nonlinear function of gravity dam.

Key words: gravity dam, non-probabilistic reliability, Kriging model, interval variables, anti-slip stability