Risk Assessment Due to Terrorist Actions on Public Transportation Networks: A Case Study in Portugal

Abstract

The work presented in this paper was performed in collaboration with one of the largest Public Transportation Operator in Portugal and addresses the problem of risk assessment due to terrorist actions involving explosions at different levels. First, a region of the Operator is selected. The elements in the Operator's network with the highest associated risk are highlighted for each threat using the COUNTERACT guidelines. Subsequently, from the group of elements with the highest associated risk, an element is selected for structural safety evaluation under blast loading. Through numerical analysis, different explosion scenarios are studied and the behavior of the structure is presented.

Numerical Analysis of an Earthen Masonry Structure Subjected to Blast Loading

“…The accuracy of the FEM model is ensured by comparing the eigenvalue analysis results to a previously created model of the Torre de la Vela calibrated to the building using dynamic identification [1]. Though the modeling strategy was not calibrated experimentally within this work, this strategy has been previously validated experimentally by other authors, in which the numerical and experimental results were found to be consistent [18,[32][33][34][35].…”

“…The CDP model also assumes that damage plasticity characterizes the failure for tensile cracking and compressive crushing of the material and allows the definition of the strain softening in tension and strain hardening in compression. Previous studies have used the CDP model for masonry buildings under blast loading [32,33], concrete members under high strain rate [39], and rammed earth constructions under seismic events [40]. The dilation angle, flow potential eccentricity, ratio of initial equibiaxial compressive yield stress to the initial uniaxial compressive yield stress, and viscosity parameter were defined according to a previous study [41].…”

Dynamic response and safety assessment of inner‐wall corroded concrete pipeline in service subjected to blasting vibration

“…blasting vibration. 2,3 On theoretical analysis, Attewell et al 4 analyzed pipeline dynamic response through the Winkler model. Klar et al 5 took the Vesic coefficient as the basic modulus of pip-soil interaction and the Winkle model to solve the response of buried pipelines.…”

“…Currently, many scholars have done relevant research on the dynamic response of buried pipelines under blasting vibration 2,3 . On theoretical analysis, Attewell et al 4 analyzed pipeline dynamic response through the Winkler model.…”

Experimental and numerical investigation on destructive effect of gas pipeline buried in silty clay under surface explosion

“…For example, Mokhtari and Alavi Nia (2015) have established a numerical model of TNT charge explosion above X65 buried steel pipe by LS-DYNA, and used this model to study the dynamic response of buried pipeline under terrorist attack explosion load; De et al (2005) applied the centrifugal test to study the influence of buried pipeline under surface explosion impact; Kouretzis et al (2007) introduced a robust methodology for analytical calculation of the strains in flexible buried pipelines due to surface point-source blast. And a series of scholars (Du et al, 2016;Feldgun et al, 2011;Giannaros et al, 2016;Guo et al, 2019;Liu et al, 2019;Mohammsa and Rohollah, 2018;Parviz et al, 2017;Pereira et al, 2014;Sklavounos and Rigas, 2006;Tao et al, 2013;Yuen et al, 2013;Zhang et al, 2016Zhang et al, , 2018Jiang et al, 2018) used numerical simulation to analyze the dynamic response of buried pipeline or other structures under explosion load. It can be seen that many scholars have studied this aspect mostly by numerical simulation, while in the field experiment, each of them has its characteristics, Due to the complexity of various factors, numerical simulation can not take into account all-round factors, so the combination of field experiment and numerical simulation is needed to ensure the reliability of the research (Jia et al, 2017;Mirzaei et al, 2015;Wang et al, 2013;Zhang et al, 2017a).…”