Risk assessment for bridge structures against blast hazard via a fuzzy-based framework

Explosion of dangerous goods or a vehicle bomb can cause severe damages to bridge structures accompanied by serious casualties and significant economic losses. However, the studies on the blast risk assessment of bridges have been limited. This paper proposes a fuzzy-based framework for assessing the impact of blast incidents caused by dangerous goods on bridges. The proposed framework consists of a conversion system and aggregation process. Basic information about bridges is transformed into fuzzy numbers in the conversion system, and the risk grade is calculated by the aggregation progress. Using the proposed framework, a hierarchical structure for risk assessment of blast hazard on bridges is established, and the risk function is defined. Meanwhile, weight vectors of attributes are determined by the entropy coefficient method. The proposed framework is illustrated by evaluating the risk grade of seven bridges on a route. The attributes of the risk parameter are ranked, and the membership function of linguistic terms is calculated in the assessment process. In order to verify the rationality of the proposed framework, the risk grades of cases from other related studies are evaluated by the proposed method, and the obtained results are consistent with the previously reported results. The proposed framework can assess the risk grade of various hazards, and assessment results can be used for guiding the structural design considering the blast risk. In addition, the risk grade obtained by the proposed framework can serve as a reference for anti-explosion design.