Load-Bearing and Adjustment Functions of Box Columns in Bridge Bearings

Load-Bearing Function: Box columns distribute the upper load of the bridge (such as vehicles and self-weight) evenly to the lower structure through a closed section. Their torsional stiffness is 5-8 times that of H-shaped columns, which can effectively disperse stress concentration.

Adjustment Function: Box columns work in conjunction with bearings to accommodate the expansion and contraction deformation of the bridge caused by temperature and load. For example, spherical bearings achieve ±50mm horizontal displacement through the PTFE sliding pair design (friction coefficient 0.03), avoiding structural constraint damage.

Synergistic Advantages: The high stability of box columns combined with the flexible adjustment of bearings can reduce the risk of bridge cracks and extend service life, especially suitable for the complex stress environment of large-span bridges.