Framework for seismic risk and access disruption analysis in road infrastructure

This chapter develops and presents an integrated framework for assessing the seismic vulnerability of road networks and their accessibility to critical services, crucial for disaster preparedness and response. The framework combines a multi-stage approach, beginning with the development of a Seismic Vulnerability Index (SVI) for roadways and their assets, incorporating selected parameters and vulnerability classifications derived through nonlinear dynamic analysis and fragility functions. Following this, a Traffic Disruption Assessment using an Accessibility Index quantifies the impact of seismic damage on mobility and access to essential facilities. The framework culminates in the creation of Transport Performance Maps to visualize spatial vulnerabilities and accessibility challenges. A case study of Penang Island, Malaysia, validates the methodology by evaluating roadway resistance, mapping seismic vulnerability, and accessibility disruptions. The chapter further introduces the Intrinsic Seismic Vulnerability Index (ISVI) to refine roadway assessment and emphasizes critical network elements influencing post-earthquake functionality. Accessibility analysis employing a Reduced Accessibility Index (AI) quantifies connectivity losses. The integrated framework demonstrates a robust tool for infrastructure resilience planning, offering practical insights for policymakers and engineers to prioritize interventions and enhance community safety during seismic events.