Modeling longitudinal driving behaviors at defective sites on urban expressways

In a model where a finite number of particles (e.g. vehicles) or sites (e.g. traffic incident sites) have different properties from the rest these are usually called defects. The defective site's impact is introduced, bringing the changes of acceleration, deceleration, random deceleration and headway. At the defect site, the vehicles decelerate spontaneously. The greater the impact is, the larger deceleration probability will be. Simulations of the proposed model and the classic NaSch model are given. The results suggest the remaining capacity of the proposed model is approximately 54.6% of that of NaSch model. Compared to empirical data, the model can describe the traffic flow at defect site better than NaSch model.