单子样结构试验可靠性评估

Reliability Evaluation of the Singular Sample Structural Test

提出了与试验件关键部位测量结果及可靠性分析计算方法相结合的小子样试验可靠性综合评估方法,阐明了基本概念,提出了试验分别至出现破坏与未出现破坏两种试验结果情况下的相应的可靠性综合评估方法,给出了具体典型方法与算例,最后提出了将来发展的方向。

Until now, the singular sample tests of structural parts of a spacecraft or an aircraft only recorded the resultant data of structural static strength or fatigue life, but the structural stress development and crack propagation process were not measured, so its reliability assessment is approximate. We presented a reliability evaluation method which is based on the measured stress and crack condition test data of structural key components or key places of structural dominant failure modes. In our method, if the test sample is destroyed, the displayed dominant failure mode is the most critical, but it is necessary to consider the other secondary critical dominant failure modes by the stress or crack conditions of the corresponding places. When all the dominant failure modes are taken into account, accurate reliability evaluation can be achieved. If the test sample is not destroyed, the structural static strength or fatigue life of the most critical dominant failure mode should be deduced. Finally, we gave the following conclusions: (1) The static strength and life of structural parts can be obtained by making full use of the measured test data of singular sample. (2) Reliability evaluation of singular sample structural test can be greatly improved by taking into consideration the influence of all dominant failure modes on reliability.