On the influence of concrete cracking in the stress distribution in some typical structures

The aim of this paper is a discussion of the effects of concrete cracking on the stress distribution in some typical structures under the effects of particular loading conditions such as the thermal steady states and transitories. In the authors' experiences the approach based on linear elastic evaluation (i.e. neglecting the changes in the stiffness matrices due to the sections changes consequent to concrete cracking) may lead to unreasonably conservative design with respect to reinforcement bars number and distribution. As it is well known, simplified procedures are suggested by current practice and codes (ACI 207-73), however it seems rather interesting to establish more accurate simplified criteria for different kinds of typical structures by means of analytical tools, whose complexity is outside the limits of the current design even for simple structures. The paper is divided into three sections: analytical tools, applications and tentative conclusions. (Auth.)