AN IMPROVED RESPONSE SURFACE METHOD FOR STRUCTURAL RELIABILITY ANALYSIS AND ITS APPLICATION

The response surface method (RSM) for structural reliability analysis is improved by proposing a new strategy for positioning sampling points. In the new strategy, one of the initial sampling points that is the most far away from the interpolate point is replaced by the interpolate point generated in every iteration step, in order to make sampling points closer to the design point on the actual limit state surface. A new group of points are then established, and the strategy is performed in the next iteration process until the convergence condition is met. So, only one structural analysis is performed in every iteration step instead of 2n+1 structural analyses are needed to be performed in conventional RSM. Examples are given to demonstrate the advantages of the new method for both computation cost and the convergence of nonlinear limit function. And the reliability analysis for a self-anchored cable-stayed-suspension bridge planed to be built is performed under service limit states by the proposed approach.