Analysis of capacity fitness of dam-to-dam waterway for the new Three Gorges channel

The navigational conditions of dam-to-dam waterway in Three Gorges is investigated and Shipai Bend is found to be the bottleneck of the waterway. The analysis of capacity fitness of the dam-to-dam waterway is equivalently transformed into the analysis of the throughput capacity of the Shipai Bend. The throughput model of Shipai Bend is constructed with the space-time consumption method. The model is designed to reflect the conditions after new Three Gorges passage is completed, the feature of traffic flow the mode of traffic management and the operation plan of the ship locks. The model parameters, such as size of ship domain and ship speed, are calibrated. The capacity fitness of the dam-to-dam waterway for new Three Gorges channel is examined against the project proposal document of the new channel project by means of the model. The results of model calculation show that for normal lock schedule, open two times for upstream traffic and two times for downstream traffic every day respectively, the throughput capacity is over 296 ships per day. The ships allowed to pass through the two dams are 263.4 ships per day and 296.8 ships per day respectively. The dam-to-dam waterway is good for the traffic volume. However, when the lock operation is adapted to unsymmetrical traffic demands and opening 3 times for upstream traffic and one time for downstream traffic, and meantime, it happens in a flood season when the dam-to-dam waterway only allows 260 ships to pass every day, its throughput capacity is not adequate. These are the circumstances where the intelligent dispatching technology can display its skill to the full.