bridge engineering;  concrete box girder;  cantilever plates;  finite elements;  Submodel technology

Combined with sub-model technology, the solid element model and the plate and shell element model are established through a large-scale finite element program respectively for numerical simulation analysis. Three methods and implementation techniques of sub-model technology in the modeling and analysis of concrete box girder cantilever slabs were studied, and the influencing factors of the internal forces of the cantilever slab were investigated: thickness, length, box girder distortion and load action position. The results show that the width of the sub-model area is closer to the effective distribution width of the cantilever plate, the more accurate and efficient the calculation results of the substep method and the mixed mesh method are. For the effective beam segment method, the beam segment that is 3 times the effective distribution width is the best scale for calculating accuracy and calculating time. The solid element modeling comprehensively considers the influencing factors, and the analysis results are closer to the test results than the analysis results of plate and shell elements and other algorithms, and the sub-model technology is suitable for the local fine analysis of concrete box girder cantilever plates.