AbstractThis paper presents a model to quantify the functionality of the physical systems at urban scales using a finite element–based approach. The methodology identifies the functionality of physical systems within an urban area and captures the interaction between infrastructures. Following the finite-element (FE) approach, the Intensity Measure (IM) parameters such as PGA, PGV, etc., are modeled as external perturbation forces. The building’s characteristics are assigned to two-dimensional (2D) elements whose edges overlap with the roads. The discretization of the urban area is based on a preliminary identification of the critical nodes corresponding to the transportation network (e.g., roads junctions, highway forks, etc.) and strategic infrastructures (e.g., shelters, hospitals, etc.). Lifelines (transportation, water, telecommunication, power networks, etc.) are instead modeled as one-dimensional (1D) elements. The constitutive parameters of each element are identified by a novel procedure that considers the inherent fragilities and economic losses of each physical system. The proposed finite-element formulation is capable of spatially quantifying the functionality of the built environment following a seismic event while taking into account the interdependency among physical systems.