IMPROVED APPROACH TO MODELLING PRELOAD RELAXATION IN BOLTED COMPOSITE JOINTS

This paper studies the long-term performance prediction for the preload of bolted composite joints. An analytical model based on the authors' previous work was improved, with transferring expressions of different creep stages into segmented forms and modified the use of time-temperature shift factor. Accelerated tests were designed and performed for characterizing the long-term relaxation behavior. Comparisons between the results of the predicted model and accelerated test results indicated that the improved model provided a better validity than existing models such as Shivakumar-Crews's model and Hook-Norton's model for describing the long-term preload behavior.