Process towers or vertical vessels are among the industrial structures that play a key role in the production Process of petroleum products and their derivatives in refineries and oil and gas industries. Due to the vulnerability of these structures in past earthquakes, and the lack of valid regulations and methods for seismic analysis and design of these structures, a case study on a designed and constructed Process tower 26.5 meters high, located in Qeshm Island Refinery, has been conducted in this research. Since considering a rigid foundation, without the interaction of soil and structure, may lead to wrong results, in this study, the tower has been modeled in Abaqus finite element software considering soil behavior. The Winkler model used for soil modeling and the seismic behavior of the tower was investigated using pushover and incremental dynamic analysis, and finally, the resulting fragility curve is presented to show the structure's vulnerability at different levels of seismic intensities. In this investigation, the probable failures, including the failure of the body and the skirt, as well as the overturning of the structure, have been investigated. According to the incremental dynamic analysis results, no buckling was observed in the body and the tower's skirt before the tower overturned. The results show that overturning was the predominant failure mode and the probability of this failure mode until PGA=0.1g is approximately equal to zero, and for PGA= 0.35g, this probability is less than 20%. But for rare seismic intensities, the overturning probability is considerable.

How to profoundly change the beliefs of the polytheists during the age of revelation from the denial of the Prophet (pbuh) to the certainty of his Message and the acceptance of his full guardianship is a question worthy of attention. The order of verses about prophecy based on the order of revelation is the reason to lead a transformative Process and a special Quranic method in institutionalizing the belief of prophecy in the lives of Arabs. In the first stage, the Holy Quran in the first Makkī (Arabic: المکّیّ, suras revealed in Mecca) chapters has prepared the community from the motivational side to accept the truth of the Prophet’s (pbuh) prophecy and briefly stating the key issues surrounding it. The Holy Book of Quran at the time of the emergence of oppositions and doubts (the second stage) destroyed the arguments of the polytheists and explained the prophecy and proved its authenticity from a cognitive perspective in the second stage by presenting clear arguments. and the Holy Book of Quran in the third stage after Madanī (Arabic: المدنیّ, suras revealed in Medina) period has undertaken measures in order to fulfill the goals of the Massage by explaining the true position of the Prophet (pbuh) to deepen and operationalize the Prophetic belief through explaining practical duties for the Prophet (pbuh) and behavior based on the acceptance of Walaya (Arabic: ولایة, meaning “guardianship” or “governance”).

Evaluation of seismic vulnerability of very flexible structures such as high-rise petrochemical and refinery stacks (chimney) and power plant chimneys is a challenging problem in earthquake engineering. Their equipments and structures are often considered as vital facilities and thus they must be fully functional after even very strong ground motions. From other point of view, numerical modeling of such mega-structures with numerous elements may not allow to consider all details of mechanical characteristics of consisting materials, particularly nonlinear performance of elements during large deformations. Therefore, a simplified model corresponding to dynamic characteristics of whole structure is substantially needed to investigate seismic performance and failure modes of these essential structures subjected to strong ground motions. The procedure for developing a 2-D simplified nonlinear model based on moment-curvature in some plane-sections of a 3-D sophisticated model but linear system having almost identical dynamic properties is discussed. If micro elements be used for structural modeling of the chimney like structures, static nonlinear analysis or dynamic linear analysis will be economically suitable for assessment investigation. But of the most important problems in earthquake behavior of the structures is hysteretic behavior of material and section properties. The significance of this study, if any, is mainly concentrated on model simplification that provides sufficient accuracy based on a nonlinear discrete model. Tous power-plant chimney is investigated numerically as an example.

Imprecise construction work might cause imperfection in the shell of RC. hyperbolic cooling towers. By considering the three directions concrete fracture model and by using elements in Finite Element analysis which could crack in three directions, it could be shown that in imperfect shell, the thickness cracks occur at the end of the weight and thermal loads. In the other words, the inside and outside of the concrete shell separate. The number of such cracks rises up by increasing the imperfection in the cooling tower shell. This increase in number of cracks could multiple when two concavity and convexity imperfections happen consecutively. Since there is not any reinforce bar for preventing of such cracks, so it must be avoided by precise construction work and by modifying the participating thermal load factor in combining loads.

The wet cooling towers are one of the main consumers of water in oil and gas refineries as well as petrochemical companies for producing cooling water. If an optimum selection of cooling systems is considered in the design phase and retrofit operations in a factory, considerable water consumption savings will be achieved. For modifying existing systems to determine the best optimal option among all the alternatives available, the mathematical modeling and optimization of such plans can replace expensive laboratory or pilot plant methods previously used. In this study, using the mixed integer linear programming along with the operational experiences of the first superstructure plan, a network of cooling towers was created. In the next step, the most favorable model is regarded in two scenarios to reduce raw water consumption and cooling tower blowdown production with producing demine water (DM) required by the factory. The optimum scenario results in producing 200 m3h-1 DM water and reducing 480 m3h-1 cooling tower blowdown and 200m3h-1 raw water consumption. This scenario results are confirmed and it is now installed in ammonia plant (unit 1). The functions of NPV, IRR, and Payback are used to determine the economic criteria of the plan.

Airport Traffic Control towers (ATCT's) are among the most critical structures in an airport that are expected to keep their level of serviceability during and after server disasters like strong earthquakes. Seismic vulnerability of these structures is the matter of great importance during immense ground motions due to their high sensitiveness to structural and non - structural damage. On the other hand, few of these towers are constructed using special structural systems compared to the ordinary residential and industrial structures, because of their uncommon topology and expected function. Therefore analysis and design of these structures cannot be performed using common building codes and methods, but needs a detailed investigation on the seismic behavior of the structure based on the geotechnical characteristics of its site. The control tower under the study is a reinforced concrete structure consisting of four symmetric flexural flanges connected with floor slabs in twelve elevations. The dynamic analysis of the structure is performed by ANSYS finite element program. The lateral forces are estimated performing spectral analysis. The ultimate strength of the structure and the cracking patterns are revealed through a nonlinear static push - over analysis.