Coastal areas due to geographic location, biodiversity and dependent ecosystems are sensitive and delicate areas. In this study, the sensitivity of the coastal ecosystems of the South Pars region has been determined, and the results have been evaluated by using Expert Choice software. Since, the south Pars region is constantly exposed to the drilling and extraction of the oil and gas wells, the JACK-up drilling platform is identified as one of the pollutant factors in the region and its effects as a pollutant factor on the Different ecosystems have been analyzed. In order to assess risk through the basic definitions of risk assessment, as well as application of mathematical techniques, the probability, the severity of consequences, and the importance of habitat have been identified and calculated. In this study Fuzzy concepts are used for quantifying the qualitative parameters. In order to validate the results, the calculated mathematical model was compared with the actual values. The results of environmental events over a period of four years indicated the importance of considering environmental risks in drilling operation by JACK-up, which is needed for management and protection of sensitive ecosystems in the region.

In order to model real behavior of JACKup PLATFORMS subjected to environmental conditions, a nonlinear dynamic analysis considering soil-structure interaction subject to wave loading is investigated. For this purpose, spudcans behavior, soil nolinear behavior near the structure, contact phenomena at the interface of the soil and foundation such as gapping as well as geometrical nonlinear behavior of the structure are considered. The soil which is used in this study is assumed to be granular with varying friction angles. Beam on Nonlinear Winkler Foundation method (BNWF) is a suitable model for soil media modeling. For wave loading two methods were used, monochrome wave and irregular waves representing a sea state. Results of this study show that inelastic behavior of the soil causes an increase in displacement at hull elevation and permanent unequal settlement in soil below the foundations which is increased by decreasing friction angle of soil. In fact spudcans and the underlying soil cause a relative fixity at support of the platform which changes dynamic response of structure compared to the case where the structure is assumed to have a fixed support.

At present study, leg welding joints of Super M2 JACK up are evaluated by structural analysis. By reviewing other researches, it is recognized that JACK up joints were analyzed by applying simplified supports. In this research, another method is developed.At first, considering the Persian Gulf environment, JACK up platform model was generated and analyzed deterministically, then critical joint by considering welding volume was modeled in finite element software and it was analyzed by applying displacements of neighbor joints (by using the results of JACK up platform analysis) as its boundary condition. By analyzing the model, it is considered that using displacements of vicinity joints around the critical joint as boundary condition has more accurate results than applying simplified support; also Super M2 JACK up platform has reasonable structural strength in Persian gulf conditions. Finally, according to the truss shape of legs, changing of direction for environmental forces do not have essential effects on magnitudes of maximum stresses in legs structure, but the positions of occurrence is variable.