Author(s): Jean-Robert Ladouceur; Tadros Ghobrial
Linked Author(s): Tadros Ghobrial, Jean-Robert Ladouceur
Keywords: Ice jam; Ice mechanics; Sensitivity analysis; Ice control structure
Abstract: The design of an ice control structure (ICS) is intended to reduce the risk of ice-induced floods along a specific river reach. Typically, ICSs consist of a weir, which slows down the flow, on top of which equally spaced piers intercept floating ice blocks. To properly design these ICSs, estimating the dynamic ice forces exerted on them is essential. The current design norms are to use the estimation of ice forces on bridge piers (CSA, 2019). Nevertheless, the relative effects of the different hydrometeorological parameters on the estimated ice forces on ICS have never been investigated. Therefore, the main objective of this study is to perform a global sensitivity analysis of ice characteristics and hydrometeorological parameters affecting the estimation of ice force on ICSs. For this purpose, the Sartigan ICS (referred to as Sartigan Dam) is used as a case study. The Sartigan Dam is located on the Chaudiere River, 3 km upstream of the Town of St-Georges, Quebec, Canada and consists of a 7 m high weir and 12 piers distanced every 6.1 m forming 11 openings. The results show that wind speed and ice cover length play a significant role in ice forces when a static ice cover is present with no bottom gates opened. For the case of an ice jam, hydraulic parameters such as flow and water surface slope, as well as ice thickness and cover length, become important in estimating the ice forces. Finally, in the case of an ice jam with one bottom gate open (i. e., active management of the dam), the impact of the hydraulic parameters and ice characteristics are reduced, but the effects of the wind speed and ice cover length increased for the calculated ice forces.
Year: 2024