On dynamic behavior and failure of high lock bolted joints: Testing, analysis and predicting

A bidirectional synchronous dynamic loading technique based on electromagnetic split Hopkinson tensile bar (ESHTB) system was employed to investigate the dynamic behavior and failure of high lock bolted joints. Force-displacement curves over wide ranges of loading speed (5 × 10−6 m/s to 15 m/s) and loading state (tension, shear and three kinds of tension-shear coupling) were obtained by combining with results obtained from quasi-static tests. An obvious elevation of failure load levels when changing the loading state from shear to tension or improving the loading speed was observed. Meanwhile, such strengthening effect of loading state on failure loads presented positive correlation with the loading speed. Detailed analysis for effect of loading state on mechanical behavior of bolted joints was conducted by applying von Mises yield criterion together with failure load analysis. Moreover, on this base, the influence of loading speed on failure loads was reasonably defined by applying a relation equal to the different strain rate effect between shear and tension for bolt material. Finally, a failure criterion considering coupling effect of loading speed and loading state on failure load of bolted joint was proposed. Prediction results showed a good agreement with the experimental results, indicating the determination of failure loads for bolted joints under different loading states over a wide range of loading speeds can be achieved.