ABSTRACT
The structural designer has to take serviceability – and ultimate-limit states into account when choosing layout and materials as there exists no universally used tool, which can consider both simultaneously. A tool for the ultimate limit state is the Finite Element Limit Analysis, which can perform material optimisation on a ground structure, which has been proven effective. Here the serviceability limit state is adapted to fit the optimisation in order to handle both limit states simultaneously in a convex solver.
As a first step towards a general tool, the method is set up for bar elements and applied to concrete structures yielding a so-called strut and tie model. For simple ground structures, the tool reproduces known solutions. For large scale structures subjected to multiple load cases the tool shows good results but did suffer from minor numerical instabilities.
