Modeling Floating Objects at River Structures

Abstract

More than half of the commercially navigable waterways in the United States are adversely impacted at some time by ice and debris conditions that hinder operation and delay navigation. This paper describes a method of combining a depth-averaged two-dimensional flow model and a discrete element model customized to simulate floating objects such as ice and debris. The flow model is the shallow-water equation module of the adaptive hydraulics system. The discrete element model (DEM) is based on a method that has been used to simulate river ice and debris accumulations and vessels such as barges. The modeling system provides designers of hydraulic structures, bridges, and ice control structures, a physically based method to evaluate design alternatives in dealing with problems due to the presence of floating objects. Descriptions of the flow model and the DEM are presented, and then numerical applications are provided, demonstrating the modeling of debris passage at the Harlan Diversion Tunnel and the evaluation of navigation conditions attributed to the guard wall at the Greenup Locks and Dam.