Hybrid multi- and inter-modal transport simulation: A case study on large-scale evacuation planning

Transport simulation models exist on multiple scales from evacuation simulations of nightclubs with a few hundred guests over the simulation of transport hubs such as large train stations up to evacuation simulations of megapolis in case of tsunamis. Depending on precision and complexity requirements, continuous (e.g. force-based, velocity obstacle based), spatiotemporal discrete (e.g. cellular automata), or queue models are applied. In general, the finer the spatiotemporal resolution the more precise the interactions between travelers (e.g. pedestrians or vehicles) are captured, but the computational burden increases. The obvious approach to achieve higher computational speeds is to reduce the physical complexity (e.g. by using a queue model), which in turn also reduces the precision. One way to increase the computational speed while staying precise enough to make reliable prognosis is to combine models of different scale in a hybrid manner, where a finer model is applied where needed and a coarser model where plausible. This contribution discusses an application of a hybrid simulation approach in the context of a large-scale multi- and inter-modal evacuation scenario. The presented case study investigates the feasibility of an evacuation of parts of the city of Hamburg in Germany in case of a storm surge.