Impact of bridge piers on ice jam stage variation:An experimental study

In the vast northern regions, ice jam can be easily formed during winter times, which can further result in ice jam flooding. Due to the presence of bridge infrastructures, the flow field can also be complicated. To study the impact of bridge pier on ice jam, the present study was conducted. By using experimental approach, the mechanism of backwater height variation was measured. It shows that the presence of bridge pier significantly changes the backwater height during ice jam. The ice jam evolution can be classified as "before pier" and "after pier" conditions. Erosion on ice jam around bridge piers can also be noted, which further complicate the ice jam stage development. It is also found that with or without bridge pier, the mechanism of backwater height shows similar trend under different flow conditions and ice discharge. However, with a larger diameter, the backwater height variation is larger under the same flow and ice conditions. With the same blockage ratio, double piers can results in a higher backwater height increase comparing to a single pier.