The Risk Assessment Study Of Ocean Platform Under The Effects Of Ice-induced Vibration In Liaodong Bay

With the rapid development of ecnomy and Marine science and technology,Marine has become the source of wealth and the new dawn of solving the sustainableeconomic and social development along with the further development and applicationof Marine resources.Offshore oil and gas development and utilization is the importantcontent of Marine resources, however, a large number of offshore explorationequipments and Marine platforms are working in a complicated Marine environmentin the near polar and cold waters of the sea oil and gas development.The platformswould produce strong ice-induced vibration response under the effect of sea ice in thewinter sea ice area, the structures of offshore platform would have obvious vibrationeffect when the vibration frequency close to or reach to the natural frequency ofoffshore platform.Therefore, ice induced vibration effection has become the mostimportant risk factor of safety production and structural instability in sea platforms,to a certain extent, offshore engineering facilities will have initiated collapse, oil spill,casualties and other project disasters if the risks of sea ice, current, earthquake andother environmental loads are considered improper. So, this paper puts a specialemphasis on analysis and research of risk assessment under the action of offshoreplatform ice-induced vibration based on the measured datas which regard to inherentcharacteristic and winter Marine environment on JZ20-2MUQ platform in LiaodongBay, which provides an important theoretical basis for the safe operation of theMarine engineering facilities prevention and management measures of oceanengineering disasters.First of all, this paper introduces the basic situation of domestic and internationalMarine platform facilities risk assessment，and providing the theoretical guide for thedeeper research and analysis of the offshore platform risk assessment which under theaction of ice-induced vibration.Secondly, this paper summarizes about the related concepts about Marineplatform risk assessment, and comprehend Marine platform risk assessment of thebasic methods. Meanwhile, according to make full use of the measured datas whichabout inherent characteristic and Marine environment on JZ20-2MUQ platform inLiaodong Bay, we have obtained the natural frequency which under the ice-inducedvibration effect and the forced vibration frequency under the action of theenvironmental loads both in the extreme conditions, and provided the basis for therisk assessment of offshore platform.Thirdly, this paper makes further discussion joint probability distribution abouteach risk events and risk factors in the process of platform risk assessment, and focuson the research about extreme joint probability distribution between ice andenvironmental loads， meanwhile, we will get the probabilistic information ofrandomness and the relativity, then conduct a study on risk assessment about the safeuse of JZ20-2MUQ platform by the method of grey relational analysis.Finally, we will obtain the risk assessment conclusion of the offshore platformstructure system through the analysis and research, and puts forward relevantsuggestions and measures for ice ocean platforms rationalization management.