Direct Damage-Controlled Design of Concrete Structures

The basic methods of structural concrete design that have been developed so far cannot directly control damage, either at the local or the global level. In order to develop an integrated scheme for direct damage control during design and study its application in practice, a new design philosophy, named direct damage controlled design, is proposed. In spite of the generality of the presented design philosophy, this paper focuses on the beam type of structures composed of plain concrete or other quasi-brittle materials, such as masonry or ceramics, and subjected to statically applied loading. The proposed methodology appropriately combines code-based stress -strain relations with a simple expression for damage to determine with the aid of the fiber model and the finite-element method axial force and bending moments of a beam-column element as functions of deformation and/or damage. Five characteristic numerical examples are presented to illustrate the proposed methodology and demonstrate its direct applicability to structural design.