Uncertainty analysis of aircraft bolt group connection clearance design using k-out-of-n model

Uncertainty exists in the design parameters of machinery, electronic products and other fields. The bearing performance of bolt group connection is related to the effective clearance of single bolt in the load direction, and the bolt group connection bearing reliability can be described by the k-out-of-n model. Under the condition that the load direction is determined, the bolt diameter and the positional tolerance and diameter of the hole are regarded as random variables, the uncertainty propagation analysis model of the bolt effective clearance is established, and the transmitted load probability of the single bolt is obtained. Regarding the bolt group connection of an aircraft windshield as the research object, the relationship between bearing risk and probability distribution of effective clearance is discussed. The analysis results show that the three-layer uncertainty propagation model proposed can be used for further study about bolt group connection design and fatigue life analysis.