American Journal of Civil Engineering 2015; 3(2-2): 80-85 Published online December 17, 2015 (http://www.sciencepublishinggroup.com/j/ajce) doi: 10.11648/j.ajce.s.2015030202.26 ISSN: 2330-8729 (Print); ISSN: 2330-8737 (Online) Evaluation of Ten Thousand Cubic Meters Mazut Tank Behavior Against Explosive Charges Saeid Azmoodeh * , Nasser Arafati Department of Civil Engineering, University of Tafresh, Tafresh, Iran Email address: Saeid.azmoodeh66@gmail.com (S. Azmoodeh), Nasser.arafati@gmail.com (N. Arafati) To cite this article: Saeid Azmoodeh, Nasser Arafati. Evaluation of Ten Thousand Cubic Meters Mazut Tank Behavior Against Explosive Charges. American Journal of Civil Engineering. Special Issue: Research and Practices of Civil Engineering in Developing Countries. Vol. 3, No. 2-2, 2015, pp. 80-85. doi: 10.11648/j.ajce.s.2015030202.26 Abstract: Considering the terrorist threats and blasts, which may occur to destroy a structure, the effect of explosive on a 10 thousand cubic meter Mazut tank of Mashhad Cement Company is studied. This article studies the behavior of 10 thousand cubic meter tank of storing Mazut with the help of ABQUS 3D software. The explosive considered is TNT, which is studied in distances of 15, 25, 50, 100, 200 meters to the structure and with various thicknesses of the tank wall. Finally, the results indicate that by the increase of the wall thickness, the blast effect will mitigate. Also due to the surface wave generated, by the reduction of the blast distance to the structure, the effectiveness of the blast wave will be greater and ultimately, in a distance less than 15 meters, the tank will collapse. Keywords: Tank, Explosive Loading, ABAQUS Software, Performance Evaluation 1. Introduction Considering the terrorist threats and blasts, which may occur to destroy a structure, the effect of explosive on a 10 thousand cubic meter Mazut tank of Mashhad Cement Company is studied. According to the definition of chapter 21of Iran National structure regulations (Passive defense), explosion is a reaction, in which the burning rate of materials is done with a speed much more than the speed of sound, resulting in the generation of a very high pressure and temperature gradient and the shock wave is generated immediately, which will spread with a high speed [4]. In terms of the classification, the explosion type can be natural, physical, nuclear and chemical. In terms of physical, the explosions caused by the sudden failure of the tanks under pressure or volcanic eruption can be referred. In nuclear explosions it is based on the core separation and the Neutrons and Protons distribution loading, whereas in chemical explosion, the rapid oxidization of elements such as Carbon and Hydrogen can be noted. The explosives can be in the form of solid, liquid and gas, but the explosion of solids has usually the greatest effect in terms of the force released [1]. The explosives can also be classified in terms of the primary and secondary forces, which are exerted on the structures or they can be classified due to the activation of these materials through using condiments such as spark, flame or strike. The secondary stage of an explosion is in fact, the wave generated from that explosion, which can cause a lot of damages to the environment. Among very common explosives, TNT (Tri Nitro Toluene) can be referred. The explosive, TNT can generate a pressure equal to 300 Kb and a temperature of about 3000 to 4000 Celsius degree. After the explosion the expanded hot gas and a layer of compressed air generate (explosion wave). This wave raises the amount of environment atmospheric pressure at about the gas pressure and the pressure behind the wave will be lower and a relative vacuum due to air intake behind it is generated. This cycle is completed in the next round and it generates the explosive shocks. The pressure exerted by the explosion shocks mitigate with the distance increasing from the explosion source. The pressure graph in terms of distance from the blast site is shown in figure 1 [1]. Between the years 1928 to 1945 a series of tests were carried out by the headquarters of the Japanese army on the striking blast to a three-storey building with a change in the thickness of the slabs. The result showed that by the increase of the slab thickness in the ceiling of the roof, the intrusion of the bomb inside the building is prevented [6]. Bing Li & Toe Chien (2008)[5], analyzed two reinforced