The accidental release and ignition of flammable vapours in petrochemical facilities generate overpressure and drag LOAD which can impact the safety of installation and people. The intensity of the blast LOADs depends on many influencing factors including congestion, geometry, type & amount of fuel, leak size, and points of ignition among others. Given the stochastic nature of these parameters, it is obvious that the design for accidental LOAD must be determined using a probabilistic method. This paper discusses a methodology known as “EXPLOSION exceedance diagram” and draws on recent developments in vapour cloud EXPLOSION research to determine the design accidental LOAD (DAL). A case study demonstrates the application of the method.

One of the kinds of structural floors system is consisting of profiled steel sheet and dry board which connected to each other by self-drilling and self-tapping screws. The aim of this research is study on the behavior of mentioned floor under EXPLOSION LOAD. For this purpose, effect of various parameters such as: thickness of dry board and profiled steel sheet, kind of bry board, screw spacing, boundary conditions, floor dimensions, duplicate of mentioned surfaces, and also weight and distance of explosive material from the center of floor, on the nonlinear dynamic behavior of the mentioned floor is studied. This study is performed by using numerical finite element method taking advantage of ABAQUS software. The research results show by varying parameters such as: thickness and kind of bry board, dimensions and boundary conditions of floor, duplicate of main elements, and also distance and weight of explosive materials, significant changes in floor maximum displacement and strain energy is created, but varying of other above mentioned parameters not create significant changes in them. The profiled steel sheet and dry board reach to their yield stress under various structural conditions and floor LOADing, though in many cases, they not reach to their yield stress. The results of current research present great help to researchers and designers in identification effective and ineffective parameters on the behavior of studied floor under EXPLOSION LOAD.

Most of underground structures are designed and built to withstand the effects of precision penetrating weapons and heavy bombs in the soil. Usually the depth of the structures is high and there is no possibility of missiles to the main structure. Accordingly, the design of these structures is performed for blast LOADs. The EXPLOSION phenomenon is a type of high strain rate problem that requires dynamic analysis to solve. Also, due to the interaction between underground structures and soil, the analysis of these structures is affected by any type of nonlinear analysis. Thus, the analysis of underground structures in simulations affected by the EXPLOSION is a high strain rate problem that requires nonlinear dynamic analysis. There are two implicit and explicit solutions to dynamic analysis that, given the EXPLOSION problems, their analysis is explicitly integral. The LOADing of underground structures is often based on the relationships obtained from theoretical and experimental research. Currently, the most important reference for explosive LOADing in the field of underground structures is the US code (TM5-855-1) provided by the US army. The numerical simulation methods have recently been widely used as a novel method in the calculation of nonlinear dynamic LOADs. According to the researchers, among the explicit software available in AUTODYN software, due to its ability to solve very high strain rate problems, it yields good results from simulation and EXPLOSION problem analysis. On the other hand, the explosive LOADing of underground structures is often based on theoretical and empirical research. In this study, a numerical simulation method was used to analyze and simulate the effect of the surface EXPLOSION on the underground structure. Also, all the simulation steps were performed using AUTODYN hydrocode. In order to analyze the LOADing and response of underground structures, the effect of the explosive charge weight and the depth of burial of the structure has been studied and the numerical results have been compared with the relationships presented in reliable US scientific and guidance sources. Finally, suggestions are made to improve the LOADing of these structures. Also, considering the results of the LOAD on the roof of the structure, it was observed that the values of the US code are conservative compared to the other two methods. Therefore, it is recommended not to apply 1. 5 incremental coeficient LOAD to the structure in accordance with this instruction. The numerical simulation results including a comparison of maximum pressure and the velocity values with the values provided in the by code (TM5-855-1) showed that the predicted values for the maximum pressure values larger than of instructions America's Army. The reason for this is that the code assumes that the investigations take place in the full EXPLOSION range (mating coefficient f = 1), while in the numerical model under consideration, the EXPLOSION is formed at the joint surface of air and soil. Hence the coupling coefficient is equal to (f = 0. 4). In other words, the depth of the explosive charge is almost zero and there is little difference between the results.

With the increasing expansion of the technology for the production of high- tech military equipment, the need to build structures with acceptable resistance against EXPLOSION in vital centers increasingly felt. These structures as the facilities in times of peace and in times of war and natural disasters are contributing to saving lives. Due to the lack and limitation of experimental data for EXPLOSION problems, numerical modeling based on finite element method can help in designing and estimating the LOADs exerted on structures. In this research, the effects of sacrificial RC slab on the performance of underground arched shape RC structures with practical details under EXPLOSION LOAD were studied. Ls-Dyna finite element software was used to solve the problem and optimized concrete arches under different levels of explosives were investigated. Results show that, if a sacrificial RC slab is placed on the crown of the study structure, no damage will occur in structure and structural damages will be concentrated in RC slab. However these damages will be increased with increasing of the explosives. On the other hand, sacrificial slab distributes the blast waves at a higher level of soil which in turn shield the structure against EXPLOSION. Consequently, the safety of the structure in terms of performance against blast LOADing will be increased significantly.

For this reason and in order to be registered in the medical sources of the world, we plan to register this new type of terrorism injury in the medical sources of the world under the title “pager EXPLOSION trauma" or “pager trauma”. We invite all our colleagues in all countries and especially in Lebanon to publish their articles about the characters of this injury.Based on field observations and expert opinions, it seems that these injuries will cause lifelong disability, and this is a terrible tragedy that needs international response, and these injured patient need urgent specialized treatment at this stage and should be treated in the future.Publishing of experiences and treatments modalities about this injury will help physicians to give better medical services.

Background and Aim: It is believed that a period of healing, approximately 3-4 months for mandible and 4-6 months for maxilla, are required to ensure osseointegration. Recently, a new method called Immediate LOADing of implants have been proposed. This method provides improved stability of the implant by the immediate support of an iterim prosthesis. The aim of this study was to evaluate the success rate of the Immediate LOADing single OPILS dental implants.Materials and Methods: Thirty-nine patients, including 26 females and 13 males, at the minimum age of 18 and maximum age of 54 years old, received 48 OPILS dental implants. In this prospective study, all samples were non-smoking, without any systemic disease or psychological problem. In all cases, and acrylic prefabricated crown was placed immediately after implant surgery. The definitive metal-ceramic crown was placed 2.5 months later in mandible and 5.5 months later in maxillae. Lack of pain, pus, implant immobility and less than 1mm bone loss were criteria of success.Results: The oral hygiene of females were better than males, 26 women had plaque index (0) and 11 of them had plaque index (1) where as out of 13 male subjects, 4 had plaque index (0), 6 had plaque index (2) and (3) had plaque index (3). The mean vertical bone loss, on mesial and distal parts, were less than 1mm, with the min. of 0 and max. of 0.4mm and the average of 0.2mm. All implants pass the defined criteria of success.Conclusion: On the basis of this short-term study, in single tooth cases, OPILS implants of Neo-Dent system can be LOADed immediately.

Background: Fire and EXPLOSION hazards are considered as the first and second major hazards in process industries. Objective: The aim of this study was to quantitatively assess the fire and EXPLOSION hazardsas well as relative classification of such hazards in a petrochemical industry. Methods: This wasa quantitative study in which the process units were selected based on parameters affecting the risk of fire and EXPLOSION. Later, these parameters were analyzed using DOW’s fire and EXPLOSION index (F&EI). Technical data to determine the index were obtained through process documents and reports as well as the fire and EXPLOSION guideline. Following calculating the DOW’s index, the high and low risk process units were determined. Findings: The stripper column with a rank of 226 and the naphtha tank with a rank of 64 were determined as the most and least disastrous process units. The level of hazardwas determined as severe for columns (F&EI>158), heavy for magna-former reactor and gasoline furnace (127< F&EI£158), and moderate for hydrodealkylation reactor and naphtha tank (61< F&EI£96). The radius of exposure was calculated at 57 meters for stripper column. Conclusion: The fire and EXPLOSION index is a suitable measure to determine the high and low risk areas of an industry. The stripper column as the most disastrous process unit needs more sensitive methods for hazard assessment.

Background: Fire and EXPLOSION accidents cause numerous economical, environmental and human losses in industries.Objective: The aim of this study was to present a new method for fire and EXPLOSION loss estimation by virtue of fire and EXPLOSION index to determine the premium rate.Methods: This is a descriptive-analytical study carried out in Bandar Imam petrochemical complex in 2006. Initially, the fire and EXPLOSION index was calculated in selected process units and the hazard radius, equipment value, and the base maximum probable property damage determined. To determine the actual maximum property damage, the loss control credit factor was assessed. Finally, the days’ outage and business interruption losses were estimated.Data analyzed with DOW fire and EXPLOSION software.Findings: The stripper column with 226 F&EI value, actual maximum property damage of about 6.7 million dollars, days’ outage of about 120 days, and business interruption loss of about 89 million dollars was identified as the most critical unit of the factory. The least hazardous unit detected was the Nafta storage tank with 64 F&EI value and actual maximum property damage of about 0.36 million dollars.Conclusion: All factors affecting the fire and EXPLOSION risk were shown to be among the indices that are considered as a base for loss estimation. Business interruption losses are higher than actual maximum property damage and these losses are not insured in Iran industries. In this technique, the effects of control measures on reducing fire and EXPLOSION losses were considered and the estimated losses could be regarded as a base to determine the premium rate.

With the increasing cost of petrol for Iranian customers, the interest in using dual fuel cars is increasing widely. It is common to use CNG vessels in Iranian dual-fuel cars. Nowadays there are millions of CNG vessels with more than 10 years of Commissioning time in Iran. In this study, the burst CNG car tank performance of steel reinforced concrete (RC) columns was numerically investigated with Abaqus software; and using Phast software for modeling equivalent TNT force exertion. Recently, the number of EXPLOSIONs of CNG tanks is increasing which has caused a lot of casualties and financial losses. In this study, the effect of CNG tank EXPLOSION on the Reinforced concrete column was investigated by considering four variables, including the distance between the CNG tank and column, reduction of the resistance of the car body, strength of concrete, and dimensions of the column’s section. Investigations showed that the most effective parameters according to the changes of the examined parameters are 1) distance between CNG tank and column and reduction of the resistance of the car body 2) section area of a column and 3) strength of concrete as, by increasing distance from 50 to 130-centimeter the maximum displacement decreased 63 %, by decrease the resistance of the automobile body to 80% the maximum displacement decreased 64%, by change strength of concrete from 20 to 40 Mpa the maximum displacement decreased 15% and by increase section from 35×35 to 50×50 cm2 the maximum displacement decreased 45%.