Allocating emergency service vehicles to serve critical transportation infrastructures

To maximize the service coverage to Critical Transportation Infrastructures (CTIs), this research formulates an integer programming model that optimizes the simultaneous allocation of multiple types of emergency service vehicles among a set of candidate stations. Sufficient coverage of a CTI is achieved only when all types of emergency service vehicles are each individually capable of reaching the CTI within the specified distance standard and reliability level. A variant of the model that gives more emphasis to the highly critical transportation infrastructures relative to the less critical transportation infrastructure is also proposed. Data obtained from Singapore is used to illustrate the applications of the models to a relatively large city. The scenarios of allocating various fleet sizes of fire engines, fire trucks, and ambulances to 15 fire stations to cover 151 CTIs are demonstrated.