NEW METHODS IN SYSTEMS RELIABILITY

The dissertation comprises three areas of research: reliability analysis of truss and frame structures, parametric sensitivity analysis and use of simulation based techniques to estimate reliability. ln the first part of the thesis, we extend currently used reliability analysis procedures for truss and frame structures to allow more realistic modeling of non-linear behaviour. Current procedures are restricted to structure models with "two-state" elements and static proportional loads. The elements, semi•brittle truss members and rigid-plastic hinges, can be in either their initial (safe) state or their yielded (failed) state. Structure failure can be defined in terms of sequences of element failures and the structure failure event can be formulated as a union of intersections of element failure events. First order reliability methods are then used to compute the structure reliability. We extend this methodology to truss structures with multi-state elements under proportional and non-proportional loads. We also extend it to frame structures with moment/axial-force interaction effects.