This work presents the robustness assessment of stiffened thin-walled composite structures in postbuckling, which is based on a new design strategy that satisfies weight, load-based performance and energy-based robustness requirements. In this approach, robustness is understood as collapse insensitivity due a local failure, where global buckling for instance is assumed as a local failure, once ...

We discuss this problem through fiber bundle model (FBM) -where a bundle of fibers is subjected to external load and fibers have distributed thresholds. External load is increased quasi-statically -which produces 'bursts' (number of failing fibers) of diffrent sizes. The burst statistics shows a robust crossover behavior near the failure point which can be treated as a signature of imminent fai...

In rigid plastic analysis one of the most widely applicable methods that is based on the minimum principle, is the combination of elementary mechanisms which uses the upper bound theorem. In this method a mechanism is searched which corresponds to the smallest load factor. Mathematical programming can be used to optimize this search process for simple fra...

An adaptable algorithm is proposed in this study, which can predict the complete load-shortening curve of a stiffened panel subjected to uniaxial longitudinal compression. The provides an extension existing empirical formulae initially derived for predicting ultimate compressive strength panels. Based on observations from series nonlinear finite element analyses, behaviour panels idealised with...

Identification of critical or weak buses for a given operating condition is an important task in the load dispatch centre. It has become more vital in view of the threat of voltage instability leading to voltage collapse. This paper presents a Fuzzy approach for ranking critical buses in a power system under normal and network contingencies based on Line Flow index and voltage profiles at load ...

To meet the ever increasing load demands in a power system and to satisfy the stability and reliability criteria, the existing transmission lines have been forced to operate closer to their security limits. As a result, several voltage instability incidents have been reported all over the globe. One of the major being the voltage collapse problems in power systems which have been a permanent co...

This paper presents dynamic voltage collapse prediction on an actual power system using support vector regression. Dynamic voltage collapse prediction is first determined based on the PTSI calculated from information in dynamic simulation output. Simulations were carried out on a practical 87 bus test system by considering load increase as the contingency. The data collected from the time domai...