Refined Stress Check of Special Concrete Box Girder Bridges at Serviceability Limit State

For shallow beams, stick models are frequently used to perform the stress check at serviceability limit state with the plane section assumption. However, the behaviour of specialprestressed concrete box girder bridges, such as multi-cell box and curved box girder bridges, is more complicated than shallow beams and does not comply with the plane section assumption exactly. As a result, the load distributions and spatial effects in the structure should be analysed clearly when doing the stress check at serviceability limit state. A proper spatial model called spatial grid model is used in this paper for the behaviour analysis of specialprestressed concrete box girders. Two examples are listedin this paper.In the last part, a refined stress check method based on plate elements is proposed to ensure the safety of specialthin-walled structures.