Performance and its indexes in the life-cycle design of the concrete structures

Abstract

In order to promote the performance-based design methods used in civil engineering field, from the concept and approach of structure performance, the basic requirements of structural performance design are analysed, and the factors which need considering when choosing performance indexes are considered, and based on the existing structure design code, a three-level performance index system on structural life-cycle performance design is constructed, including risk performance index, technical performance index and material performance index. Each level performance index includes multi-parameters of performance design to control structural life-cycle performance from different angles. For the structural technical performance, three new performance indexes are put forward, which are the diffusion depth of deleterious mediums, the corrosion degree of steel bar and the corrosive crack width, as controlling indexes of durability design for concrete structures. Designers may choose different performance indexes for controlling the structure design to meet the individual requirements of owners or users.