Dynamic traveler response model for seismic risk analysis of transportation systems

Earthquakes could significantly impact road network capacity and further change spatial and temporal traffic demand patterns. This paper presents a practically useful dynamic traveler microassignment model to simultaneously capture variable traffic demand and departure time choice dynamic for different trip purposes. These travel choice dimensions are integrated in a stochastic utility maximization framework that considers multiple user decision criteria, such as travel time and schedule delay. For a typical case that assumes the logit-based alternative choice model, this paper develops an equivalent gap function-based optimization formulation and a heuristic iterative solution procedure. A case study using a large-scale transportation network (adapted from the Salt Lake City metropolitan area) is presented to illustrate the capability of the proposed system integration for realistic traffic impact studies. Experimental results from two network damage scenarios show the dramatic changes in postearthquake traffic demand, departure time, and route choice patterns; a small amount of capacity loss in critical links could lead to substantial networkwide travel time increases.