Fail-safe design often leads to oversized structures as the design must be able to behave properly for the different accidental situations that could undergo throughout their lifespan. The existing research about structural optimization applied to fail-safe design does not contemplate the idea of having accidental situations with different probabilities of occurrence. This means that the structure must satisfy the design constraints in the damaged structure regardless of whether one accidental situation is much more likely than another. The objective of this research is to formulate a new optimization strategy to get fail-safe structures with minimum weight taking into account the available data about the probability of occurrence associated to each partial collapse. A multi-model probabilistic optimization problem is defined and applied to two structures: a 2D truss structure with stress constraints as well as the tail section of an aircraft fuselage with stress and buckling constraints.

故障安全设计通常会导致结构过大，因为设计必须能够针对其整个生命周期中可能发生的各种意外情况正确运行。有关应用于故障安全设计的结构优化的现有研究并未考虑具有不同发生概率的意外情况的想法。这意味着该结构必须满足损坏的结构中的设计约束，而不管一种意外情况是否比另一种意外情况大得多。这项研究的目的是制定一种新的优化策略，以考虑到与每个局部坍塌相关的发生概率的可用数据，以最小的权重获得故障安全结构。