Buckling Load Prediction of Axially Compressed Pre-Twisted Plates Using the Vibration Correlation Technique
摘要
Plates are crucial structural components, and techniques for predicting their buckling loads are a critical concern, as buckling can lead to sudden and catastrophic failure. Predicting buckling loads accurately helps improve design and ensure the safety of structural components.
ObjectiveThis study investigates the buckling load and behaviour of pre-twisted plates, aiming to verify the vibration correlation technique (VCT) as a reliable method for predicting buckling loads through comparison with experimental results.
MethodsA specially designed fixture is used to apply a pre-twist angle to the plates, ensuring that they experience initial angular strain–a common real-world scenario. Plates with diverse length-to-width ratios are prepared, and axial compression is gradually applied while maintaining a constant pre-twist angle. Vibration analysis is conducted at various stages of compression, and then the VCT is used to predict the buckling load.
ResultsThe pre-twist angle significantly enhances bending rigidity. It improves the limit load by up to 50% and a linear relationship is noted between the pre-twist angle and the limit load. Conversely, the post-buckling response remains essentially unchanged. Mixed modes are observed at higher initial angular strain values, causing a decrease in the accuracy of VCT predictions. Although the VCT is a reliable method for flat and slightly twisted plates, its performance degrades with increasing geometric complexity, and deviations reach up to 22.7%.
ConclusionThe pre-twist significantly affects the buckling behaviour. It is reported that the VCT is a partially robust method at lower pre-twist angles, and its use in geometrically non-standard plates requires further methodological refinement.