Random variables and dependent interval variables often coexisted,and this made the reliability analysis problem into a double-loop optimization problem and reduces the efficiency of the reliability analysis.So an one-step reliability analysis method was proposed.Specifically,the doubleloop optimization problem where the dependent interval variables were modelled by the ellipsoid model,was decoupled into a simple one-step problem by using the HDMR.Based on the proposed sampling strategy,aquadratic polynomia...