2D Numerical Simulation Study on Influence of Bridge Superposition on Water Flow Regime

With more and more intensive bridge construction, the superposition of the water blocking and turbulence influence of river piers has increased the complexity of river flow. A numerical simulation and an analysis are conducted on the influence of the superposition of the proposed Xin’an River Grand Bridge and Yanjiang Bridge in a flood control reservoir area on the flow regime based on two-dimensional shallow water equations. When the flood peak passes, the backwater effect of Yanjiang Bridge and the proposed Xin’an River Grand Bridge will be superposed, leading to an increase in the backwater height and scope of the proposed bridge upstream. At the same time, the proposed bridge will make an impact on the backwater from the completed Yanjiang Bridge downstream. When the flood peak passes, the proposed bridge will make a significant impact on the flow velocity near the piers of Yanjiang Bridge downstream, while Yanjiang Bridge will have less influence on the flow velocity around the proposed bridge.