Twin cylindrical bridge piers are widely used in practical engineering and inevitably impacted by open-channel flow during their service life, i.e., floods. The interaction between twin columns and water flow could cause different fluid characteristics and eventually influences the hydrodynamic force. Conventional study mainly takes the single isolated pier or tandem twin piers as examples. The shielding effect are investigated with this condition. But the effects of staggered angle and distance between twin cylindrical piers on the shielding effect have remained unclear.
Here, the researchers conducted the numerical analysis to investigate their effect on hydrodynamic forces. The model is verified using experimental test data from a simplified experimental platform, which utilize the relative movement between structure and fluid particles. It indicates that the interaction between fluid flow and twin piers results in shielding factor with upstream pier <1.0. The staggered angle and distance between piers apparently influence the hydrodynamic force on the downstream pier, where the shielding factor reaches 1.2 with staggered angle 20°~30° and S/D 3~4.
This work provides a new understanding of hydrodynamic force on twin bridge piers considering the staggered angle and distance. The work entitled “Numerical investigation of hydrodynamic force on twin cylindrical piers with open-channel flow” was published on Journal of Railway Science and Technology (published on June 30, 2026).