DYNAMIC RESPONSE OF STRUCTURES TO INTERNAL BLAST LOADING EFFECT

Abstract

The present research work deals with the study of the behavior of structures under the effect of steam boiler internal explosion. An extensive survey of real accidents of steam boiler explosions is conducted, and emphasis is placed on cases where the boiler is located in a separate boiler room, separated from the main factory building. The concept of boiler gas explosion strategies and the “equivalent TNT charge methods” are evaluated for different operating fuels and described in detail. This includes pre-blast considerations, fuel physical properties, heat of release, combustion of different fuels, pool fire, ignition rate and TNT specifications. The developed analytical algorithm is based on finite element modeling “FEM” in LSDYNA program which is used for structural damage analysis under explosion effect. This includes constitutive material models for concrete, reinforcing steel as well as high energy explosive and its equations of state. A three-dimensional numerical model has been simulated for both single wall and closed room to set the confinement percentage and the effect of the Presence–Absence of air with different loading charges and elastic-inelastic material conditions. Extensive validation of the proposed model has been illustrated by comparing the developed model results for selected cases to the corresponding results obtained by the application of both “TM5-1300 American code of practice formulas”, and similar models developed using CONWEP program.