Application of Machine Learning to the Development of Calculation Model for Stress Concentration Factor of Concrete-Filled Steel Tubular T-Joints Under Axial Force in the Brace
摘要
Concrete-filled steel tubular (CFST) joints have been widely applied to arch bridges in China. Recently, the fatigue cracks seriously damaging the structural safety were found at the chord-brace intersection in this type bridges. Against such a situation, stress concentration factors (SCFs) have been formulated for CFST joints based on the results of detailed finite element (FE) analyses using the least-squares method. However, their accuracy depends on the form of the function to be set in advance, and it may be difficult to set an appropriate form of the function. In addition, the creation of many FE models requires a great deal of time and effort. To solve these problems, this study attempted to use neural networks (NNs), which can perform regression analysis even with a small number of data and does not require to set the functional form, for SCF calculation of CFST T-joints under axial force in the brace. Furthermore, a method for generating the minimum training data required for the NN to have sufficient accuracy was proposed.