• Explosives and Blasting
• /
• v.38 no.1
• /
• pp.1-13
• /
• 2020

Gas explosion accidents are steadily being issued due to increased gas consumption in Korea and foreign countries. To analyze the effects of these gas explosions, a TNT equivalent method is used. In this study, the TNT equivalent was calculated in the event of an explosion due to the volume content in the air of CO, CH₄ and C₂H₄, the typical flammable gases emitted by coal. Also, the peak overpressure and impulse variation with the distance from explosion point were compared and analyzed by gas using the calculated equivalent value of TNT. The upper limit of the TNT equivalent for the three mixed gases is up to five times larger than the other gases mixture. In addition, the peak overpressure and impulse, which are factors of the TNT characteristic curve, are also increasing as the number of gases increases.

• Explosives and Blasting
• /
• v.35 no.1
• /
• pp.1-17
• /
• 2017

The understanding of the pressure associated with air blast, which travels through air, and its effect on surface and underground structures is highly important. It is necessary to determine the pressure change with time and distance for a computer simulation of the explosion impact on a structure. From the previous studies, many empirical equations for estimating the parameters related to the pressure change. In this study, the empirical equations for predicting peak overpressure, duration of positive phase, impulse, minimum negative pressure, duration of negative pressure, arrival time, and decay constant were reviewed and analyzed. Also, the pressure changes predicted from the Kingery equation, which is the most commonly used, and from the other empirical equations were compared.