Decision-Making Support for Selection of Design Ideas at the Early Phase of Structural Design

Abstract

There are a large number of uncertainties of the design variables and the requirements while the decision-making process at the early phase of design has the greatest effect upon the lead time of development and the overall cost. Designers need to figure out an outline of the structural feature and have to compare the evaluation results of diverse design ideas from multiple aspects under some uncertain design information at the early phase of structural design. We have proposed a preference set-based design (PSD) method that generates a ranged set of design solutions that satisfy sets of performance requirements. This study proposes a decision-making support method for the early phase of structural design based on the PSD method that is possible to analyze, obtain and compare diverse design ideas with design uncertainty and variability by elastic FEM. We apply the proposed method to a structural form of a bridge with uncertainties of cross-section area of members and dimension of structure (coordinates of geometry) under fluctuating distribution of performance characteristics of the maximum stress and the mass.