Numerical study on erosion of mono-pier in hyper concentrated flow environment

Abstract

To study the erosion characteristics of mono-pier in hyper concentrated flow environment, a three-dimensional numerical model describing the pier erosion process is established based on the finite element method. First, the effectiveness of the new erosion model is validated through existing laboratory tests. Then, using this model, the influences of flow conditions, sediment concentration, particle diameter and pier characteristics on the erosion behavior of mono-pier and the evolution of the mono-pier bearing capacity in the erosion process are studied in detail. Finally, an erosion prediction method under the multiple influencing factors is established through orthogonal regression experiments. The numerical results demonstrate that there is a positive correlation between the flow velocity, particle diameter, and sediment content and the mono-pier erosion rate. However, the mono-pier erosion rate is inversely associated with compressive strength and water depth. In addition, the influences of flow velocity, particle diameter and sediment content on erosion of mono-pier are more obvious than other factors, and the ultimate bearing capacity of mono-pier gradually decreases with the development of erosion. This study can provide scientific reference for the bearing capacity assessment of mono-pier in sediment laden flow environment.