Analysis of internal explosion and structural response to blast loading

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2012
Turcan, Uğur Can
In this thesis, blast overpressure due to internal explosion and dynamic response to this loading of the structure is analyzed. Firstly, theoretical backgrounds of computational procedures are presented. The basic principles of the hydrocodes and semi empirical methods are explained in detail. In the analysis of blast overpressure, partially vented structures are examined. Three different venting areas and three different charge weights are employed in the study. Peak pressure, time and impulse parameters are investigated in detail. Remapping and scaling laws are employed in order to reduce the computational cost. Experiments are carried out with similar conditions where pressure histories are recorded. Results from a semi empirical program and a commercial hydrocode are compared with the experimental data. After investigating the accuracy of blast calculation methods, dynamic response to blast loading is reviewed. For this purpose, two methods are used: The fully coupled method in hydrocode and the hybrid method - uniquely coupled semi empirical program and hydrocode. In the fully coupled method, hydrocode solves both blast and response; whilst in the hybrid method, hydrocode is used as the structural solver and semi empirical program is employed for the blast calculation. A deformable test setup is used to observe the response. Results from computational methods are compared with the experimental data. Finally, it can be concluded that semi empirical program and hydrocode are applicable to blast overpressure problems with partial venting. In addition, the methods introduced in dynamic response section can be used as preliminary analysis tools in the prediction of structural response to blast loading. Also, it is shown that the hybrid method is much faster than the fully coupled method in hydrocode.

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Citation Formats
U. C. Turcan, “Analysis of internal explosion and structural response to blast loading,” M.S. - Master of Science, Middle East Technical University, 2012.