Abstract
This study deals with a principal component analysis about limit state functions for structural systems reliability assessment. Although it is pointed out that the measure must be important such as directional cosine of limit state functions on standardized space, we can discuss about characteristics both variances and covariance of limit state functions from other view points. It is proposed that the problem can be solved by using the method of principal component analysis of covariance matrix of limit state functions according to reliability indices. This approach can be explained about the important measure considered as geometry of members of structural system.
