Research And Analysis On The Weight Transfer Process Of Deep-sea Production Structure

With the rapid development of the national economy, China’s demand for energyis growing quickly. Because the energy resource of land is decreasing, theexploitation of energy resource of sea, especially deep-sea, has become an inevitabletrend. The rise of deep-sea oil production industry has led the platform of deep-sea oilproduction to be large-scale and comprehensive, making the weight of platformheavier, construction and installation of platform more difficult. For the jacketplatform, gravity platform and SPAR platform, the installation of platform is usuallydone in the sea. There are mainly two ways of installation, which are the floatingcrane installation and float-over installation. The float-over installation costs lessmoney and time consuming. Compared with floating crane installation, fewer factorscan affect float-over installation, and the lifting capacity of float-over installation islarger, which is very suitable for installation of large or medium-sized platform. Thereare several shipment ways of oil platform, which use float-over installation. No matterwhich way, the weight of oil platform is carried through construction legs to slide inthe construction process, but in the shipment process, the weight of oil platform iscarried through shipment structure to slide. The weight of deep-sea oil platform istransferred, which needs the weight transfer device. There are little design andresearch of weight transfer device at home and abroad.Based on the weight transfer process of deep-sea oil platform, this paperresearches several aspects of weight transfer device. The main research content is asfollows:1. Use the theory of foundation bearing capacity and composite foundation, andbased on the specific situation of slide5#of Li-wan3-1project in Qingdao, todetermine the bearing capacity of slide5#through the load test method, and calculatethe composite modulus and equivalent poisson ratio of every part of compositefoundation;2. Design the structure of weight transfer device. And according to the specificsituation of slide5#, three kinds of weight transfer devices have been established.3Dmodel of weight transfer devices is built by using Pro/Engineer, and is imported to thefinite element analysis software ANSYS Workbench. The stress and deformation of weight transfer devices is analyzed in different conditions;3. Analyze the loading situation of the slide board of slide5#. Calculate thepunching shear strength and partial bearing capacity, and use SACS to analyze thebearing capacity of pile foundation, to guarantee the safety of slide board and pilefoundation in weight transfer process;4. Build finite element model of each part of slide5#in weight transfer process,including soil model, slide board model, soil-pile composite model and weighttransfer device model. According to each working condition of weight transferprocess, the stress and sedimentation of overall finite element model of slide isanalyzed. At the same time, DSF model etc is established to do the analysis of thewhole slide after weight transfer process;5. Based on the hydraulic lifting and moving experimental system, straindetection system is built by using optical fiber sensors. When the weight ofexperimental system is transferred through lifting jack to supporting leg, the force anddeformation of supporting leg are detected and analyzed. The weight transfer processis researched through the experiment.In conclusion, the design and research of weight transfer device of deep-sea oilplatform structure in this paper has important engineering significance.