Forensic Engineering Technique for Analysis of an Explosion Incident

This article investigates the validity of current forensic practices to analyze an explosion event. The real explosion incident at Erawan shrine in central Bangkok on August 17, 2015 is selected as a case study. By comparing the structural damage at the blast site to that obtained from FE analyses, an equivalent bare charge weight of TNT used in the incident can be estimated. It is found that an equivalent bare charge TNT weight of 3 kg could possibly be used for the bomb. Furthermore, the cased charge weight can be calculated based on the equivalent weight of bare TNT charge. To confirm the validity of the calculated explosive weight, a combined lethal zone from blast pressure and scattered fragments was analysed. Human damage from blast pressure is analysed based on the Bowen’s lethality curves. Lethality zone from exploded fragments is drawn based on a 50% probability of lethality which considers hit density and kinetic energy of fragment. The analysed lethal zone agrees reasonably well with the actual observed damage level. With the proposed forensic engineering technique, the management and policies for homeland security can be improved for a safer community.